cdp_hub/internal/ui/shell.go

package ui

import (
	"context"
	"errors"
	"fmt"
	"image"
	"image/color"
	"net/url"
	"path/filepath"
	"strconv"
	"strings"

	"chub/internal/domain"
	"gioui.org/io/key"
	"gioui.org/layout"
	"gioui.org/op/clip"
	"gioui.org/op/paint"
	"gioui.org/unit"
	"gioui.org/widget"
	"gioui.org/widget/material"
	"golang.org/x/exp/shiny/materialdesign/icons"
)

type page uint8

const (
	pageInstances page = iota
	pageSettings
	pageCreate
)

const (
	instanceNameColumnWeight      = 20
	instanceBrowserColumnWeight   = 10
	instanceDirectoryColumnWeight = 29
	instancePortColumnWeight      = 10
	instanceStatusColumnWeight    = 13
	instanceActionColumnWeight    = 18
)

var (
	instanceStartIcon  = mustIcon(icons.AVPlayArrow)
	instanceStopIcon   = mustIcon(icons.AVStop)
	instanceEditIcon   = mustIcon(icons.EditorModeEdit)
	instanceDeleteIcon = mustIcon(icons.ActionDelete)
)

type PathField string

const (
	PathChromeExecutable PathField = "chrome_executable"
	PathEdgeExecutable   PathField = "edge_executable"
	PathDefaultUserData  PathField = "default_user_data_dir"
	PathLogDirectory     PathField = "log_directory"
)

type PathSearcher func(context.Context, PathField, string) (string, error)

type DirectoryChooser func(context.Context) (string, error)

// ProxyOption is a non-secret proxy item exposed to the UI. Server has already
// been validated as an unauthenticated scheme://host:port endpoint.
type ProxyOption struct {
	ID     string
	Name   string
	Server string
}

type InstanceStartOutcome struct {
	PID             int
	RemoteDebugPort int
	External        bool
	Source          string
	Warning         string
}

type InstanceStarter func(context.Context, InstanceRow, SettingsState) (InstanceStartOutcome, error)

// InstanceStopper requests graceful shutdown only for the supplied configured
// instance. Implementations must reject external or unverified processes.
type InstanceStopper func(context.Context, InstanceRow) error

// InstanceRefreshResult carries a read-only status check for one configured
// instance. The UI applies it only while the row's editable fields still match
// the snapshot passed to the refresher.
type InstanceRefreshResult struct {
	ID              string
	Status          string
	PID             int
	RemoteDebugPort int
	OccupancySource string
	Message         string
}

// InstanceRefresher performs background status checks only for the supplied
// configured instances. It must not enumerate or take control of unrelated
// browser processes.
type InstanceRefresher func(context.Context, []InstanceRow) ([]InstanceRefreshResult, error)

type instanceStartState struct {
	request uint64
	running bool
}

type instanceStartResult struct {
	id      string
	request uint64
	outcome InstanceStartOutcome
	err     error
}

type instanceStopState struct {
	request        uint64
	running        bool
	previousStatus string
}

type instanceStopResult struct {
	id      string
	request uint64
	err     error
}

type instanceRefreshState struct {
	request uint64
	running bool
}

type instanceRefreshResult struct {
	request   uint64
	snapshots map[string]string
	results   []InstanceRefreshResult
	err       error
}

type pathSearchState struct {
	request uint64
	cancel  context.CancelFunc
	running bool
}

type pathSearchResult struct {
	field   PathField
	request uint64
	path    string
	err     error
}

type directoryPickState struct {
	request uint64
	cancel  context.CancelFunc
	running bool
	target  directoryPickTarget
}

type directoryPickResult struct {
	request uint64
	path    string
	err     error
}

type directoryPickTarget uint8

const (
	directoryPickCreate directoryPickTarget = iota
	directoryPickEdit
)

type proxyPickerTarget uint8

const (
	proxyPickerCreate proxyPickerTarget = iota
	proxyPickerEdit
	proxyPickerSettings
)

type proxyPickerState struct {
	open   bool
	target proxyPickerTarget
}

// InstanceRow is the Gio view model for one configured browser instance.
// Runtime fields are refreshed independently and are never saved by the edit form.
type InstanceRow struct {
	ID              string
	Name            string
	Browser         string
	UserDataDir     string
	TargetURL       string
	ProxyID         string
	PID             int
	RemoteDebugPort int
	OccupancySource string
	Status          string
}

type SettingsState struct {
	ChromePath           string
	EdgePath             string
	DefaultDir           string
	LogDir               string
	RemoteDebugStartPort int
	CloseOnExit          bool
}

// Shell owns every interactive Gio widget. Keeping this state outside Layout
// prevents focus, editor content, and list scroll position from resetting.
type Shell struct {
	theme *material.Theme
	page  page

	instancesClick  widget.Clickable
	settingsClick   widget.Clickable
	newClick        widget.Clickable
	refreshClick    widget.Clickable
	startClick      widget.Clickable
	createClick     widget.Clickable
	backClick       widget.Clickable
	instanceDirPick widget.Clickable
	chromePick      widget.Clickable
	chromeSearch    widget.Clickable
	edgePick        widget.Clickable
	edgeSearch      widget.Clickable
	dataPick        widget.Clickable
	dataSearch      widget.Clickable
	logPick         widget.Clickable
	logSearch       widget.Clickable
	saveClick       widget.Clickable
	cancelClick     widget.Clickable

	chromePath         widget.Editor
	edgePath           widget.Editor
	dataDir            widget.Editor
	logDir             widget.Editor
	remoteDebugPort    widget.Editor
	closeOnExit        widget.Bool
	instanceName       widget.Editor
	instanceDir        widget.Editor
	instanceURL        widget.Editor
	createProxyPick    widget.Clickable
	editProxyPick      widget.Clickable
	settingsProxyPick  widget.Clickable
	browserKind        widget.Enum
	editName           widget.Editor
	editDir            widget.Editor
	editURL            widget.Editor
	editPort           widget.Editor
	editBrowserKind    widget.Enum
	editDirPick        widget.Clickable
	editSave           widget.Clickable
	editCancel         widget.Clickable
	editBlocker        widget.Clickable
	editDiscardBlocker widget.Clickable
	editDiscardSave    widget.Clickable
	editDiscardDrop    widget.Clickable
	editDiscardStay    widget.Clickable
	pathFeedback       string
	formFeedback       string
	editFeedback       string
	proxyServer        widget.Editor
	proxySave          widget.Clickable
	proxyDelete        widget.Clickable
	proxyFeedback      string
	proxies            []ProxyOption
	createProxyID      string
	editProxyID        string
	settingsProxyID    string
	nextProxy          uint64
	proxyPicker        proxyPickerState
	proxyPickerBlocker widget.Clickable
	proxyPickerNone    widget.Clickable
	proxyPickerChoices map[string]*widget.Clickable
	proxyDeleteConfirm widget.Clickable
	proxyDeleteCancel  widget.Clickable
	proxyDeleteBlocker widget.Clickable
	pendingProxyDelete string
	proxyDeleteFocus   bool

	list               widget.List
	rows               []InstanceRow
	selectedInstanceID string
	rowClicks          map[string]*widget.Clickable
	startClicks        map[string]*widget.Clickable
	editClicks         map[string]*widget.Clickable
	deleteClicks       map[string]*widget.Clickable
	deleteConfirm      widget.Clickable
	deleteCancel       widget.Clickable
	deleteBlocker      widget.Clickable
	startStates        map[string]*instanceStartState
	startResults       chan instanceStartResult
	stopStates         map[string]*instanceStopState
	stopResults        chan instanceStopResult
	refreshClickState  instanceRefreshState
	refreshResults     chan instanceRefreshResult
	nextInstance       uint64
	instanceFeedback   string
	pendingDeleteID    string
	editingID          string
	editOriginal       InstanceRow
	pendingEditDiscard bool
	editFocusPending   bool
	focusRestoreID     string
	onSave             func(SettingsState)
	onInstancesChanged func([]InstanceRow)
	onProxiesChanged   func([]ProxyOption)
	instanceStarter    InstanceStarter
	instanceStopper    InstanceStopper
	instanceRefresher  InstanceRefresher
	pathSearcher       PathSearcher
	invalidate         func()
	searches           map[PathField]*pathSearchState
	searchResults      chan pathSearchResult
	directoryChooser   DirectoryChooser
	directoryPick      directoryPickState
	directoryResults   chan directoryPickResult
}

func NewShell(theme *material.Theme) *Shell {
	s := &Shell{theme: theme, rows: []InstanceRow{
		{ID: "demo-operations", Name: "运营主账号", Browser: "Chrome", UserDataDir: `C:\Users\Public\chub\profiles\operations`, PID: 18420, RemoteDebugPort: 9666, Status: "运行中"},
		{ID: "demo-ads", Name: "广告投放", Browser: "Edge", UserDataDir: `C:\Users\Public\chub\profiles\ads`, Status: "启动中"},
		{ID: "demo-assets", Name: "素材采集", Browser: "Chrome", UserDataDir: `C:\Users\Public\chub\profiles\assets`, PID: 16108, RemoteDebugPort: 9668, OccupancySource: "browser_message_window", Status: "外部已关联"},
		{ID: "demo-backup", Name: "备用环境", Browser: "Edge", UserDataDir: `C:\Users\Public\chub\profiles\backup`, Status: "已退出"},
	}, searches: map[PathField]*pathSearchState{
		PathChromeExecutable: {},
		PathEdgeExecutable:   {},
		PathDefaultUserData:  {},
		PathLogDirectory:     {},
	}, rowClicks: make(map[string]*widget.Clickable), startClicks: make(map[string]*widget.Clickable), editClicks: make(map[string]*widget.Clickable), deleteClicks: make(map[string]*widget.Clickable), proxyPickerChoices: make(map[string]*widget.Clickable), startStates: make(map[string]*instanceStartState), stopStates: make(map[string]*instanceStopState), nextInstance: 4, startResults: make(chan instanceStartResult, 8), stopResults: make(chan instanceStopResult, 8), refreshResults: make(chan instanceRefreshResult, 1), searchResults: make(chan pathSearchResult, 8), directoryResults: make(chan directoryPickResult, 1)}
	s.chromePath.SetText(`C:\Program Files\Google\Chrome\Application\chrome.exe`)
	s.edgePath.SetText(`C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe`)
	s.dataDir.SetText(`C:\Users\Public\chub\profiles`)
	s.logDir.SetText(`C:\Users\Public\chub\logs`)
	s.remoteDebugPort.SetText(strconv.Itoa(domain.DefaultRemoteDebugPort))
	s.closeOnExit.Value = true
	s.browserKind.Value = "chrome"
	s.editBrowserKind.Value = "chrome"
	s.editPort.ReadOnly = true
	s.list.Axis = layout.Vertical
	return s
}

func (s *Shell) SetInstances(rows []InstanceRow) {
	s.rows = append([]InstanceRow(nil), rows...)
	for i := range s.rows {
		if s.rows[i].ID == "" {
			s.nextInstance++
			s.rows[i].ID = fmt.Sprintf("restored-%d", s.nextInstance)
		}
	}
	if s.selectedInstanceID == "" && len(s.rows) > 0 {
		s.selectedInstanceID = s.rows[0].ID
	}
}

func (s *Shell) SetProxies(options []ProxyOption) {
	s.proxies = append([]ProxyOption(nil), options...)
	for _, option := range s.proxies {
		if option.ID == "" {
			continue
		}
		if strings.HasPrefix(option.ID, "proxy-") {
			if value, err := strconv.ParseUint(strings.TrimPrefix(option.ID, "proxy-"), 10, 64); err == nil && value > s.nextProxy {
				s.nextProxy = value
			}
		}
	}
	if !s.proxyExists(s.createProxyID) {
		s.createProxyID = ""
	}
	if !s.proxyExists(s.editProxyID) {
		s.editProxyID = ""
	}
	if !s.proxyExists(s.settingsProxyID) {
		s.settingsProxyID = ""
		s.proxyServer.SetText("")
	}
}

func (s *Shell) SetSettings(value SettingsState) {
	s.chromePath.SetText(value.ChromePath)
	s.edgePath.SetText(value.EdgePath)
	s.dataDir.SetText(value.DefaultDir)
	s.logDir.SetText(value.LogDir)
	port := value.RemoteDebugStartPort
	if port == 0 {
		port = domain.DefaultRemoteDebugPort
	}
	s.remoteDebugPort.SetText(strconv.Itoa(port))
	s.closeOnExit.Value = value.CloseOnExit
}

func (s *Shell) OnSave(fn func(SettingsState)) { s.onSave = fn }

func (s *Shell) OnInstancesChanged(fn func([]InstanceRow)) { s.onInstancesChanged = fn }

func (s *Shell) OnProxiesChanged(fn func([]ProxyOption)) { s.onProxiesChanged = fn }

func (s *Shell) OnStartInstance(starter InstanceStarter, invalidate func()) {
	s.instanceStarter = starter
	s.invalidate = invalidate
}

func (s *Shell) OnStopInstance(stopper InstanceStopper, invalidate func()) {
	s.instanceStopper = stopper
	s.invalidate = invalidate
}

func (s *Shell) OnRefreshInstances(refresher InstanceRefresher, invalidate func()) {
	s.instanceRefresher = refresher
	s.invalidate = invalidate
}

func (s *Shell) OnPathSearch(searcher PathSearcher, invalidate func()) {
	s.pathSearcher = searcher
	s.invalidate = invalidate
}

func (s *Shell) OnChooseDirectory(chooser DirectoryChooser, invalidate func()) {
	s.directoryChooser = chooser
	s.invalidate = invalidate
}

func (s *Shell) Layout(gtx layout.Context) layout.Dimensions {
	s.consumeSearchResults()
	s.consumeDirectoryResults()
	s.consumeStartResults()
	s.consumeStopResults()
	s.consumeRefreshResults()
	s.consumeKeyboard(gtx)
	if s.pendingDeleteID != "" {
		s.consumeDeleteConfirmation(gtx)
	} else if s.pendingProxyDelete != "" {
		s.consumeProxyDeleteConfirmation(gtx)
	} else if s.editingID != "" {
		s.consumeEditControls(gtx)
	} else {
		s.consumeControls(gtx)
	}
	mainLayout := func(gtx layout.Context) layout.Dimensions {
		return layout.Flex{Axis: layout.Horizontal}.Layout(gtx,
			layout.Rigid(s.sidebar),
			layout.Flexed(1, func(gtx layout.Context) layout.Dimensions {
				return layout.Inset{Top: unit.Dp(24), Bottom: unit.Dp(24), Left: unit.Dp(28), Right: unit.Dp(28)}.Layout(gtx, s.content)
			}),
		)
	}
	if s.pendingDeleteID == "" && s.pendingProxyDelete == "" && s.editingID == "" && !s.proxyPicker.open {
		return mainLayout(gtx)
	}
	if s.pendingDeleteID != "" {
		return layout.Stack{Alignment: layout.Center}.Layout(gtx,
			layout.Expanded(mainLayout),
			layout.Stacked(s.deleteConfirmation),
		)
	}
	if s.pendingProxyDelete != "" {
		return layout.Stack{Alignment: layout.Center}.Layout(gtx,
			layout.Expanded(mainLayout),
			layout.Stacked(s.proxyDeleteConfirmation),
		)
	}
	if s.pendingEditDiscard {
		return layout.Stack{Alignment: layout.Center}.Layout(gtx,
			layout.Expanded(mainLayout),
			layout.Stacked(s.editDialog),
			layout.Stacked(s.editDiscardConfirmation),
		)
	}
	if s.editingID != "" {
		if !s.proxyPicker.open {
			return layout.Stack{Alignment: layout.Center}.Layout(gtx,
				layout.Expanded(mainLayout),
				layout.Stacked(s.editDialog),
			)
		}
		return layout.Stack{Alignment: layout.Center}.Layout(gtx,
			layout.Expanded(mainLayout),
			layout.Stacked(s.editDialog),
			layout.Stacked(s.proxyPickerDialog),
		)
	}
	return layout.Stack{Alignment: layout.Center}.Layout(gtx,
		layout.Expanded(mainLayout),
		layout.Stacked(s.proxyPickerDialog),
	)
}

func (s *Shell) consumeControls(gtx layout.Context) {
	for s.instancesClick.Clicked(gtx) {
		s.page = pageInstances
	}
	for s.settingsClick.Clicked(gtx) {
		s.page = pageSettings
	}
	for s.newClick.Clicked(gtx) {
		s.page = pageCreate
	}
	for s.refreshClick.Clicked(gtx) {
		s.requestRefresh()
	}
	for s.createClick.Clicked(gtx) {
		s.createInstanceFromForm()
	}
	for s.instanceDirPick.Clicked(gtx) {
		s.chooseInstanceDirectory()
	}
	for s.backClick.Clicked(gtx) {
		s.page = pageInstances
	}
	for _, row := range s.rows {
		s.consumeRowKeyboard(gtx, row.ID)
		for click, ok := s.rowClickFor(row.ID).Update(gtx); ok; click, ok = s.rowClickFor(row.ID).Update(gtx) {
			s.selectedInstanceID = row.ID
			if click.NumClicks >= 2 {
				s.beginEdit(row.ID)
			}
		}
		for s.startClickFor(row.ID).Clicked(gtx) {
			s.requestInstanceAction(row.ID)
		}
		for s.editClickFor(row.ID).Clicked(gtx) {
			s.beginEdit(row.ID)
		}
	}
	for _, row := range append([]InstanceRow(nil), s.rows...) {
		for s.deleteClickFor(row.ID).Clicked(gtx) {
			s.requestDelete(row.ID)
		}
	}
}

func (s *Shell) consumeKeyboard(gtx layout.Context) {
	for {
		event, ok := gtx.Event(
			key.Filter{Name: key.NameEscape},
			key.Filter{Name: key.NameF5},
		)
		if !ok {
			return
		}
		keyEvent, ok := event.(key.Event)
		if !ok || keyEvent.State != key.Press {
			continue
		}
		switch keyEvent.Name {
		case key.NameEscape:
			if s.pendingProxyDelete != "" {
				s.cancelProxyDelete()
			} else if s.proxyPicker.open {
				s.proxyPicker.open = false
			} else if s.pendingEditDiscard {
				s.pendingEditDiscard = false
			} else if s.editingID != "" {
				s.cancelEdit()
			}
		case key.NameF5:
			if s.pendingDeleteID == "" && s.pendingProxyDelete == "" && s.editingID == "" && s.page == pageInstances {
				s.requestRefresh()
			}
		}
	}
}

func (s *Shell) consumeRowKeyboard(gtx layout.Context, id string) {
	click := s.rowClickFor(id)
	for {
		event, ok := gtx.Event(
			key.Filter{Focus: click, Name: key.NameReturn},
			key.Filter{Focus: click, Name: key.NameEnter},
		)
		if !ok {
			return
		}
		keyEvent, ok := event.(key.Event)
		if !ok || keyEvent.State != key.Release {
			continue
		}
		s.selectedInstanceID = id
		s.beginEdit(id)
	}
}

func (s *Shell) consumeEditControls(gtx layout.Context) {
	for s.editBlocker.Clicked(gtx) {
	}
	if s.pendingEditDiscard {
		for s.editDiscardBlocker.Clicked(gtx) {
		}
		for s.editDiscardStay.Clicked(gtx) {
			s.pendingEditDiscard = false
		}
		for s.editDiscardDrop.Clicked(gtx) {
			s.closeEdit("已放弃未保存的实例修改。")
		}
		for s.editDiscardSave.Clicked(gtx) {
			s.saveEdit()
		}
		return
	}
	for s.editDirPick.Clicked(gtx) {
		s.chooseDirectory(directoryPickEdit)
	}
	for s.editCancel.Clicked(gtx) {
		s.cancelEdit()
	}
	for s.editSave.Clicked(gtx) {
		s.saveEdit()
	}
}

func (s *Shell) beginEdit(id string) {
	row, ok := s.instanceRow(id)
	if !ok {
		s.instanceFeedback = "找不到要编辑的实例。"
		return
	}
	s.selectedInstanceID = id
	s.editingID = id
	s.editOriginal = row
	s.editName.SetText(row.Name)
	s.editDir.SetText(row.UserDataDir)
	s.editURL.SetText(row.TargetURL)
	s.editPort.SetText(remoteDebugPortText(row.RemoteDebugPort))
	s.editProxyID = row.ProxyID
	if strings.EqualFold(row.Browser, "Edge") {
		s.editBrowserKind.Value = "edge"
	} else {
		s.editBrowserKind.Value = "chrome"
	}
	s.editFeedback = ""
	s.pendingEditDiscard = false
	s.editFocusPending = true
}

func (s *Shell) editLocked(row InstanceRow) bool {
	switch row.Status {
	case "启动中", "停止中", "运行中", "运行中（调试不可用）", "外部已关联":
		return true
	default:
		return false
	}
}

func (s *Shell) editIsDirty() bool {
	if s.editingID == "" {
		return false
	}
	if strings.TrimSpace(s.editName.Text()) != s.editOriginal.Name || strings.TrimSpace(s.editURL.Text()) != s.editOriginal.TargetURL || s.editProxyID != s.editOriginal.ProxyID {
		return true
	}
	if s.editLocked(s.editOriginal) {
		return false
	}
	return strings.TrimSpace(s.editDir.Text()) != s.editOriginal.UserDataDir || browserDisplay(s.editBrowserKind.Value) != s.editOriginal.Browser
}

func (s *Shell) cancelEdit() {
	if s.editingID == "" {
		return
	}
	if s.editIsDirty() {
		s.pendingEditDiscard = true
		return
	}
	s.closeEdit("已取消实例编辑。")
}

func (s *Shell) saveEdit() {
	row, ok := s.instanceRow(s.editingID)
	if !ok {
		s.closeEdit("要编辑的实例已不存在。")
		return
	}
	name := strings.TrimSpace(s.editName.Text())
	if name == "" {
		s.editFeedback = "请输入实例名称。"
		return
	}
	targetURL, err := normalizeTargetURL(s.editURL.Text())
	if err != nil {
		s.editFeedback = err.Error()
		return
	}
	locked := s.editLocked(row)
	if !locked {
		userDataDir := strings.TrimSpace(s.editDir.Text())
		if userDataDir == "" || !filepath.IsAbs(userDataDir) {
			s.editFeedback = "User Data Dir 必须是绝对路径。"
			return
		}
		row.UserDataDir = filepath.Clean(userDataDir)
		row.Browser = browserDisplay(s.editBrowserKind.Value)
	}
	row.Name = name
	row.TargetURL = targetURL
	if !s.proxyExists(s.editProxyID) && s.editProxyID != "" {
		s.editFeedback = "所选代理已不可用，请重新选择。"
		return
	}
	row.ProxyID = s.editProxyID
	if !s.replaceInstanceRow(row) {
		s.closeEdit("要编辑的实例已不存在。")
		return
	}
	s.notifyInstancesChanged()
	s.closeEdit(fmt.Sprintf("已保存实例“%s”。", row.Name))
}

func normalizeTargetURL(value string) (string, error) {
	value = strings.TrimSpace(value)
	if value == "" {
		return "", nil
	}
	parsed, err := url.ParseRequestURI(value)
	if err != nil || parsed == nil || (parsed.Scheme != "http" && parsed.Scheme != "https") || parsed.Host == "" || parsed.User != nil {
		return "", errors.New("启动 URL 必须是无认证信息的 http/https 地址。")
	}
	return value, nil
}

func (s *Shell) closeEdit(feedback string) {
	id := s.editingID
	s.editingID = ""
	s.pendingEditDiscard = false
	s.editFeedback = ""
	s.editFocusPending = false
	s.proxyPicker.open = false
	s.focusRestoreID = id
	s.instanceFeedback = feedback
}

func (s *Shell) sidebar(gtx layout.Context) layout.Dimensions {
	return layout.Inset{Top: unit.Dp(24), Left: unit.Dp(16), Right: unit.Dp(16)}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
		return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
			layout.Rigid(s.navButton(&s.instancesClick, "实例", s.page == pageInstances || s.page == pageCreate)),
			layout.Rigid(layout.Spacer{Height: unit.Dp(8)}.Layout),
			layout.Rigid(s.navButton(&s.settingsClick, "设置", s.page == pageSettings)),
		)
	})
}

func (s *Shell) navButton(click *widget.Clickable, label string, selected bool) layout.Widget {
	return func(gtx layout.Context) layout.Dimensions {
		style := material.Button(s.theme, click, label)
		if selected {
			style.Background = color.NRGBA{R: 214, G: 228, B: 255, A: 255}
			style.Color = color.NRGBA{R: 0, G: 76, B: 153, A: 255}
		}
		return style.Layout(gtx)
	}
}

func (s *Shell) content(gtx layout.Context) layout.Dimensions {
	if s.page == pageSettings {
		return s.settings(gtx)
	}
	if s.page == pageCreate {
		return s.createInstance(gtx)
	}
	return s.instances(gtx)
}

func (s *Shell) instances(gtx layout.Context) layout.Dimensions {
	return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
		layout.Rigid(material.H4(s.theme, "实例").Layout),
		layout.Rigid(material.Body1(s.theme, "统一查看、启动和管理 Chrome / Edge 浏览器进程").Layout),
		layout.Rigid(layout.Spacer{Height: unit.Dp(18)}.Layout),
		layout.Rigid(s.instanceCommands),
		layout.Rigid(layout.Spacer{Height: unit.Dp(16)}.Layout),
		layout.Flexed(1, s.instanceTable),
		layout.Rigid(layout.Spacer{Height: unit.Dp(8)}.Layout),
		layout.Rigid(material.Caption(s.theme, s.instanceFeedback).Layout),
	)
}

func (s *Shell) instanceCommands(gtx layout.Context) layout.Dimensions {
	newButton := func(gtx layout.Context) layout.Dimensions {
		return material.Button(s.theme, &s.newClick, "新建实例").Layout(gtx)
	}
	refreshButton := func(gtx layout.Context) layout.Dimensions {
		label := "刷新实例状态"
		buttonGtx := gtx
		if s.refreshClickState.running {
			label = "刷新中…"
			buttonGtx = gtx.Disabled()
		}
		style := material.Button(s.theme, &s.refreshClick, label)
		style.Background = color.NRGBA{R: 230, G: 232, B: 235, A: 255}
		style.Color = s.theme.Palette.Fg
		return style.Layout(buttonGtx)
	}
	if gtx.Constraints.Max.X <= gtx.Dp(640) {
		return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
			layout.Rigid(newButton),
			layout.Rigid(layout.Spacer{Height: unit.Dp(8)}.Layout),
			layout.Rigid(refreshButton),
		)
	}
	return layout.Flex{Axis: layout.Horizontal}.Layout(gtx,
		layout.Flexed(1, newButton),
		layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
		layout.Flexed(1, refreshButton),
	)
}

func (s *Shell) instanceTable(gtx layout.Context) layout.Dimensions {
	return layout.Background{}.Layout(gtx,
		func(gtx layout.Context) layout.Dimensions {
			rect := image.Rectangle{Max: gtx.Constraints.Min}
			if rect.Empty() {
				return layout.Dimensions{Size: rect.Max}
			}
			paint.FillShape(gtx.Ops, color.NRGBA{R: 199, G: 207, B: 218, A: 255}, clip.UniformRRect(rect, gtx.Dp(8)).Op(gtx.Ops))
			inner := rect.Inset(gtx.Dp(1))
			if !inner.Empty() {
				paint.FillShape(gtx.Ops, s.theme.Palette.Bg, clip.UniformRRect(inner, gtx.Dp(7)).Op(gtx.Ops))
			}
			return layout.Dimensions{Size: rect.Max}
		},
		func(gtx layout.Context) layout.Dimensions {
			return layout.Inset{Top: unit.Dp(8), Right: unit.Dp(10), Bottom: unit.Dp(8), Left: unit.Dp(10)}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
				return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
					layout.Rigid(s.instanceHeader),
					layout.Rigid(layout.Spacer{Height: unit.Dp(4)}.Layout),
					layout.Flexed(1, func(gtx layout.Context) layout.Dimensions {
						return material.List(s.theme, &s.list).Layout(gtx, len(s.rows), func(gtx layout.Context, i int) layout.Dimensions {
							row := s.rows[i]
							return layout.Inset{Bottom: unit.Dp(8)}.Layout(gtx, s.instanceListRow(row))
						})
					}),
				)
			})
		},
	)
}

func (s *Shell) instanceListRow(row InstanceRow) layout.Widget {
	return func(gtx layout.Context) layout.Dimensions {
		return layout.Background{}.Layout(gtx,
			func(gtx layout.Context) layout.Dimensions {
				if s.selectedInstanceID == row.ID {
					rect := image.Rectangle{Max: gtx.Constraints.Min}
					paint.FillShape(gtx.Ops, color.NRGBA{R: 235, G: 242, B: 255, A: 255}, clip.UniformRRect(rect, gtx.Dp(6)).Op(gtx.Ops))
				}
				return layout.Dimensions{Size: gtx.Constraints.Min}
			},
			func(gtx layout.Context) layout.Dimensions {
				dims := layout.Flex{Alignment: layout.Middle}.Layout(gtx,
					layout.Flexed(100-instanceActionColumnWeight, func(gtx layout.Context) layout.Dimensions {
						return s.rowClickFor(row.ID).Layout(gtx, func(gtx layout.Context) layout.Dimensions {
							return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
								layout.Flexed(instanceNameColumnWeight, material.Body1(s.theme, row.Name).Layout),
								layout.Flexed(instanceBrowserColumnWeight, material.Body2(s.theme, row.Browser).Layout),
								layout.Flexed(instanceDirectoryColumnWeight, pathCell(s.theme, row.UserDataDir)),
								layout.Flexed(instancePortColumnWeight, remoteDebugPortCell(s.theme, row.RemoteDebugPort)),
								layout.Flexed(instanceStatusColumnWeight, statusLabel(s.theme, row.Status)),
							)
						})
					}),
					layout.Flexed(instanceActionColumnWeight, s.instanceActionButtons(row)),
				)
				if s.focusRestoreID == row.ID {
					gtx.Execute(key.FocusCmd{Tag: s.rowClickFor(row.ID)})
					s.focusRestoreID = ""
				}
				return dims
			},
		)
	}
}

func (s *Shell) instanceHeader(gtx layout.Context) layout.Dimensions {
	return layout.Background{}.Layout(gtx,
		func(gtx layout.Context) layout.Dimensions {
			rect := image.Rectangle{Max: gtx.Constraints.Min}
			if rect.Dy() > 0 {
				line := image.Rect(rect.Min.X, rect.Max.Y-gtx.Dp(1), rect.Max.X, rect.Max.Y)
				paint.FillShape(gtx.Ops, color.NRGBA{R: 220, G: 226, B: 235, A: 255}, clip.Rect{Min: line.Min, Max: line.Max}.Op())
			}
			return layout.Dimensions{Size: rect.Max}
		},
		func(gtx layout.Context) layout.Dimensions {
			return layout.Inset{Bottom: unit.Dp(6)}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
				return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
					layout.Flexed(instanceNameColumnWeight, material.Caption(s.theme, "实例名称").Layout),
					layout.Flexed(instanceBrowserColumnWeight, material.Caption(s.theme, "浏览器类型").Layout),
					layout.Flexed(instanceDirectoryColumnWeight, material.Caption(s.theme, "用户数据目录").Layout),
					layout.Flexed(instancePortColumnWeight, material.Caption(s.theme, "调试端口").Layout),
					layout.Flexed(instanceStatusColumnWeight, material.Caption(s.theme, "状态").Layout),
					layout.Flexed(instanceActionColumnWeight, func(gtx layout.Context) layout.Dimensions {
						return layout.E.Layout(gtx, material.Caption(s.theme, "操作").Layout)
					}),
				)
			})
		},
	)
}

func pathCell(theme *material.Theme, path string) layout.Widget {
	style := material.Body2(theme, path)
	style.MaxLines = 1
	return style.Layout
}

func remoteDebugPortCell(theme *material.Theme, port int) layout.Widget {
	return material.Body2(theme, remoteDebugPortText(port)).Layout
}

func remoteDebugPortText(port int) string {
	if port > 0 {
		return strconv.Itoa(port)
	}
	return "—"
}

func (s *Shell) instanceActionButtons(row InstanceRow) layout.Widget {
	return func(gtx layout.Context) layout.Dimensions {
		return layout.E.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
			mode := instanceActionFor(row)
			actionLabel := mode.label + " " + row.Name
			actionIcon := instanceStartIcon
			if mode.stop {
				actionIcon = instanceStopIcon
			}
			return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
				layout.Rigid(s.instanceIconButton(s.startClickFor(row.ID), actionIcon, actionLabel, s.theme.Palette.ContrastBg, mode.enabled)),
				layout.Rigid(layout.Spacer{Width: unit.Dp(6)}.Layout),
				layout.Rigid(s.instanceIconButton(s.editClickFor(row.ID), instanceEditIcon, "编辑 "+row.Name, s.theme.Palette.ContrastBg)),
				layout.Rigid(layout.Spacer{Width: unit.Dp(10)}.Layout),
				layout.Rigid(s.instanceIconButton(s.deleteClickFor(row.ID), instanceDeleteIcon, "删除 "+row.Name, color.NRGBA{R: 188, G: 51, B: 51, A: 255})),
			)
		})
	}
}

type instanceActionMode struct {
	label   string
	stop    bool
	enabled bool
}

func instanceActionFor(row InstanceRow) instanceActionMode {
	switch row.Status {
	case "运行中", "运行中（调试不可用）":
		return instanceActionMode{label: "停止", stop: true, enabled: true}
	case "启动中":
		return instanceActionMode{label: "启动中", enabled: false}
	case "停止中":
		return instanceActionMode{label: "停止中", stop: true, enabled: false}
	case "外部已关联", "外部占用", "未知占用":
		return instanceActionMode{label: "重新检测", enabled: true}
	default:
		return instanceActionMode{label: "启动", enabled: true}
	}
}

func (s *Shell) instanceIconButton(click *widget.Clickable, icon *widget.Icon, description string, iconColor color.NRGBA, enabled ...bool) layout.Widget {
	return func(gtx layout.Context) layout.Dimensions {
		if len(enabled) > 0 && !enabled[0] {
			gtx = gtx.Disabled()
		}
		style := material.IconButton(s.theme, click, icon, description)
		style.Size = unit.Dp(16)
		style.Inset = layout.UniformInset(unit.Dp(7))
		style.Background = color.NRGBA{}
		style.Color = iconColor
		return style.Layout(gtx)
	}
}

func (s *Shell) editDialog(gtx layout.Context) layout.Dimensions {
	row, ok := s.instanceRow(s.editingID)
	if !ok {
		s.closeEdit("要编辑的实例已不存在。")
		return layout.Dimensions{}
	}
	gtx.Constraints.Min = gtx.Constraints.Max
	return s.editBlocker.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
		defer clip.Rect{Max: gtx.Constraints.Min}.Push(gtx.Ops).Pop()
		paint.Fill(gtx.Ops, color.NRGBA{R: 0, G: 0, B: 0, A: 92})
		return layout.Center.Layout(gtx, s.editDialogCard(row))
	})
}

func (s *Shell) editDialogCard(row InstanceRow) layout.Widget {
	return func(gtx layout.Context) layout.Dimensions {
		if maxWidth := gtx.Dp(560); gtx.Constraints.Max.X > maxWidth {
			gtx.Constraints.Max.X = maxWidth
		}
		return layout.Background{}.Layout(gtx,
			func(gtx layout.Context) layout.Dimensions {
				rect := image.Rectangle{Max: gtx.Constraints.Min}
				defer clip.UniformRRect(rect, gtx.Dp(8)).Push(gtx.Ops).Pop()
				paint.Fill(gtx.Ops, s.theme.Palette.Bg)
				return layout.Dimensions{Size: gtx.Constraints.Min}
			},
			func(gtx layout.Context) layout.Dimensions {
				return layout.Inset{Top: unit.Dp(20), Right: unit.Dp(24), Bottom: unit.Dp(20), Left: unit.Dp(24)}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
					locked := s.editLocked(row)
					dims := layout.Flex{Axis: layout.Vertical}.Layout(gtx,
						layout.Rigid(material.H6(s.theme, "编辑实例").Layout),
						layout.Rigid(layout.Spacer{Height: unit.Dp(4)}.Layout),
						layout.Rigid(material.Caption(s.theme, "修改下次启动时使用的保存配置。").Layout),
						layout.Rigid(layout.Spacer{Height: unit.Dp(14)}.Layout),
						layout.Rigid(s.formField("实例名称", "用于在实例列表中识别此浏览器环境", &s.editName)),
						layout.Rigid(layout.Spacer{Height: unit.Dp(10)}.Layout),
						layout.Rigid(func(gtx layout.Context) layout.Dimensions { return s.editBrowserField(gtx, locked) }),
						layout.Rigid(layout.Spacer{Height: unit.Dp(10)}.Layout),
						layout.Rigid(func(gtx layout.Context) layout.Dimensions { return s.editDirectoryField(gtx, locked) }),
						layout.Rigid(layout.Spacer{Height: unit.Dp(10)}.Layout),
						layout.Rigid(s.formField("启动 URL（可选）", "仅支持 http/https；留空时启动浏览器默认页", &s.editURL)),
						layout.Rigid(layout.Spacer{Height: unit.Dp(10)}.Layout),
						layout.Rigid(func(gtx layout.Context) layout.Dimensions { return s.proxyPickerField(gtx, proxyPickerEdit) }),
						layout.Rigid(layout.Spacer{Height: unit.Dp(10)}.Layout),
						layout.Rigid(s.formField("当前调试端口", "运行时由全局起始端口分配，此处只读", &s.editPort)),
						layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
						layout.Rigid(statusLabel(s.theme, row.Status)),
						layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
						layout.Rigid(s.editFeedbackLabel(locked)),
						layout.Rigid(layout.Spacer{Height: unit.Dp(16)}.Layout),
						layout.Rigid(s.editActions),
					)
					if s.editFocusPending {
						gtx.Execute(key.FocusCmd{Tag: &s.editName})
						s.editFocusPending = false
					}
					return dims
				})
			},
		)
	}
}

func (s *Shell) editBrowserField(gtx layout.Context, locked bool) layout.Dimensions {
	buttonGtx := gtx
	if locked {
		buttonGtx = gtx.Disabled()
	}
	return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
		layout.Rigid(material.Body2(s.theme, "浏览器类型").Layout),
		layout.Rigid(material.Caption(s.theme, "Chrome 和 Edge 使用各自的启动定义").Layout),
		layout.Rigid(layout.Spacer{Height: unit.Dp(4)}.Layout),
		layout.Rigid(func(gtx layout.Context) layout.Dimensions {
			return layout.Flex{Alignment: layout.Middle}.Layout(buttonGtx,
				layout.Rigid(material.RadioButton(s.theme, &s.editBrowserKind, "chrome", "Chrome").Layout),
				layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
				layout.Rigid(material.RadioButton(s.theme, &s.editBrowserKind, "edge", "Edge").Layout),
			)
		}),
	)
}

func (s *Shell) editDirectoryField(gtx layout.Context, locked bool) layout.Dimensions {
	s.editDir.ReadOnly = locked
	buttonGtx := gtx
	if locked {
		buttonGtx = gtx.Disabled()
	}
	return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
		layout.Rigid(material.Body2(s.theme, "User Data Dir").Layout),
		layout.Rigid(material.Caption(s.theme, "浏览器独立数据目录；必须是绝对路径").Layout),
		layout.Rigid(layout.Spacer{Height: unit.Dp(4)}.Layout),
		layout.Rigid(func(gtx layout.Context) layout.Dimensions {
			return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
				layout.Flexed(1, material.Editor(s.theme, &s.editDir, "请输入或粘贴绝对路径").Layout),
				layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
				layout.Rigid(func(layout.Context) layout.Dimensions {
					return material.Button(s.theme, &s.editDirPick, "选择路径").Layout(buttonGtx)
				}),
			)
		}),
	)
}

func (s *Shell) editFeedbackLabel(locked bool) layout.Widget {
	label := s.editFeedback
	if label == "" && locked {
		label = "运行中或外部关联实例的浏览器类型和 User Data Dir 已锁定。"
	}
	return material.Caption(s.theme, label).Layout
}

func (s *Shell) editActions(gtx layout.Context) layout.Dimensions {
	return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
		layout.Rigid(func(gtx layout.Context) layout.Dimensions {
			style := material.Button(s.theme, &s.editCancel, "取消")
			style.Background = color.NRGBA{R: 230, G: 232, B: 235, A: 255}
			style.Color = s.theme.Palette.Fg
			return style.Layout(gtx)
		}),
		layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
		layout.Rigid(material.Button(s.theme, &s.editSave, "保存更改").Layout),
	)
}

func (s *Shell) editDiscardConfirmation(gtx layout.Context) layout.Dimensions {
	gtx.Constraints.Min = gtx.Constraints.Max
	return s.editDiscardBlocker.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
		defer clip.Rect{Max: gtx.Constraints.Min}.Push(gtx.Ops).Pop()
		paint.Fill(gtx.Ops, color.NRGBA{R: 0, G: 0, B: 0, A: 110})
		return layout.Center.Layout(gtx, s.editDiscardCard)
	})
}

func (s *Shell) editDiscardCard(gtx layout.Context) layout.Dimensions {
	if maxWidth := gtx.Dp(460); gtx.Constraints.Max.X > maxWidth {
		gtx.Constraints.Max.X = maxWidth
	}
	return layout.Background{}.Layout(gtx,
		func(gtx layout.Context) layout.Dimensions {
			rect := image.Rectangle{Max: gtx.Constraints.Min}
			defer clip.UniformRRect(rect, gtx.Dp(8)).Push(gtx.Ops).Pop()
			paint.Fill(gtx.Ops, s.theme.Palette.Bg)
			return layout.Dimensions{Size: gtx.Constraints.Min}
		},
		func(gtx layout.Context) layout.Dimensions {
			return layout.Inset{Top: unit.Dp(20), Right: unit.Dp(24), Bottom: unit.Dp(20), Left: unit.Dp(24)}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
				return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
					layout.Rigid(material.H6(s.theme, "放弃未保存的更改？").Layout),
					layout.Rigid(layout.Spacer{Height: unit.Dp(8)}.Layout),
					layout.Rigid(material.Body1(s.theme, "可以先保存配置，或不保存并关闭编辑对话框。").Layout),
					layout.Rigid(layout.Spacer{Height: unit.Dp(18)}.Layout),
					layout.Rigid(func(gtx layout.Context) layout.Dimensions {
						return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
							layout.Rigid(material.Button(s.theme, &s.editDiscardStay, "继续编辑").Layout),
							layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
							layout.Rigid(material.Button(s.theme, &s.editDiscardDrop, "不保存").Layout),
							layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
							layout.Rigid(material.Button(s.theme, &s.editDiscardSave, "保存").Layout),
						)
					}),
				)
			})
		},
	)
}

func (s *Shell) deleteConfirmation(gtx layout.Context) layout.Dimensions {
	row, ok := s.instanceRow(s.pendingDeleteID)
	if !ok {
		s.pendingDeleteID = ""
		return layout.Dimensions{}
	}
	gtx.Constraints.Min = gtx.Constraints.Max
	return s.deleteBlocker.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
		defer clip.Rect{Max: gtx.Constraints.Min}.Push(gtx.Ops).Pop()
		paint.Fill(gtx.Ops, color.NRGBA{R: 0, G: 0, B: 0, A: 92})
		return layout.Center.Layout(gtx, s.deleteConfirmationCard(row))
	})
}

func (s *Shell) deleteConfirmationCard(row InstanceRow) layout.Widget {
	return func(gtx layout.Context) layout.Dimensions {
		if maxWidth := gtx.Dp(420); gtx.Constraints.Max.X > maxWidth {
			gtx.Constraints.Max.X = maxWidth
		}
		return layout.Background{}.Layout(gtx,
			func(gtx layout.Context) layout.Dimensions {
				rect := image.Rectangle{Max: gtx.Constraints.Min}
				defer clip.UniformRRect(rect, gtx.Dp(8)).Push(gtx.Ops).Pop()
				paint.Fill(gtx.Ops, s.theme.Palette.Bg)
				return layout.Dimensions{Size: gtx.Constraints.Min}
			},
			func(gtx layout.Context) layout.Dimensions {
				return layout.Inset{Top: unit.Dp(20), Right: unit.Dp(24), Bottom: unit.Dp(20), Left: unit.Dp(24)}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
					return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
						layout.Rigid(material.H6(s.theme, "删除实例？").Layout),
						layout.Rigid(layout.Spacer{Height: unit.Dp(8)}.Layout),
						layout.Rigid(material.Body1(s.theme, fmt.Sprintf("确定删除实例“%s”？", row.Name)).Layout),
						layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
						layout.Rigid(material.Caption(s.theme, "不会删除 User Data Dir；若浏览器仍在运行，它会继续运行。").Layout),
						layout.Rigid(layout.Spacer{Height: unit.Dp(18)}.Layout),
						layout.Rigid(func(gtx layout.Context) layout.Dimensions {
							return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
								layout.Rigid(s.deleteCancelButton),
								layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
								layout.Rigid(s.deleteConfirmButton),
							)
						}),
					)
				})
			},
		)
	}
}

func (s *Shell) deleteCancelButton(gtx layout.Context) layout.Dimensions {
	style := material.Button(s.theme, &s.deleteCancel, "取消")
	style.Background = color.NRGBA{R: 230, G: 232, B: 235, A: 255}
	style.Color = s.theme.Palette.Fg
	return style.Layout(gtx)
}

func (s *Shell) deleteConfirmButton(gtx layout.Context) layout.Dimensions {
	style := material.Button(s.theme, &s.deleteConfirm, "删除")
	style.Background = color.NRGBA{R: 188, G: 51, B: 51, A: 255}
	style.Color = color.NRGBA{R: 255, G: 255, B: 255, A: 255}
	return style.Layout(gtx)
}

func (s *Shell) proxyDeleteConfirmation(gtx layout.Context) layout.Dimensions {
	proxy, ok := s.proxyOption(s.pendingProxyDelete)
	if !ok {
		s.pendingProxyDelete = ""
		return layout.Dimensions{}
	}
	gtx.Constraints.Min = gtx.Constraints.Max
	return s.proxyDeleteBlocker.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
		defer clip.Rect{Max: gtx.Constraints.Min}.Push(gtx.Ops).Pop()
		paint.Fill(gtx.Ops, color.NRGBA{R: 0, G: 0, B: 0, A: 92})
		return layout.Center.Layout(gtx, s.proxyDeleteConfirmationCard(proxy))
	})
}

func (s *Shell) proxyDeleteConfirmationCard(proxy ProxyOption) layout.Widget {
	return func(gtx layout.Context) layout.Dimensions {
		if maxWidth := gtx.Dp(460); gtx.Constraints.Max.X > maxWidth {
			gtx.Constraints.Max.X = maxWidth
		}
		return layout.Background{}.Layout(gtx,
			func(gtx layout.Context) layout.Dimensions {
				rect := image.Rectangle{Max: gtx.Constraints.Min}
				defer clip.UniformRRect(rect, gtx.Dp(8)).Push(gtx.Ops).Pop()
				paint.Fill(gtx.Ops, s.theme.Palette.Bg)
				return layout.Dimensions{Size: gtx.Constraints.Min}
			},
			func(gtx layout.Context) layout.Dimensions {
				return layout.Inset{Top: unit.Dp(20), Right: unit.Dp(24), Bottom: unit.Dp(20), Left: unit.Dp(24)}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
					dims := layout.Flex{Axis: layout.Vertical}.Layout(gtx,
						layout.Rigid(material.H6(s.theme, "删除代理？").Layout),
						layout.Rigid(layout.Spacer{Height: unit.Dp(8)}.Layout),
						layout.Rigid(material.Body1(s.theme, "确定删除已保存代理？").Layout),
						layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
						layout.Rigid(material.Caption(s.theme, proxy.Server).Layout),
						layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
						layout.Rigid(material.Caption(s.theme, "此操作不会修改任何实例。若代理仍被引用，Chub 会拒绝删除。").Layout),
						layout.Rigid(layout.Spacer{Height: unit.Dp(18)}.Layout),
						layout.Rigid(func(gtx layout.Context) layout.Dimensions {
							return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
								layout.Rigid(s.proxyDeleteCancelButton),
								layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
								layout.Rigid(s.proxyDeleteConfirmButton),
							)
						}),
					)
					if s.proxyDeleteFocus {
						gtx.Execute(key.FocusCmd{Tag: &s.proxyDeleteCancel})
						s.proxyDeleteFocus = false
					}
					return dims
				})
			},
		)
	}
}

func (s *Shell) proxyDeleteCancelButton(gtx layout.Context) layout.Dimensions {
	style := material.Button(s.theme, &s.proxyDeleteCancel, "取消")
	style.Background = color.NRGBA{R: 230, G: 232, B: 235, A: 255}
	style.Color = s.theme.Palette.Fg
	return style.Layout(gtx)
}

func (s *Shell) proxyDeleteConfirmButton(gtx layout.Context) layout.Dimensions {
	style := material.Button(s.theme, &s.proxyDeleteConfirm, "删除代理")
	style.Background = color.NRGBA{R: 188, G: 51, B: 51, A: 255}
	style.Color = color.NRGBA{R: 255, G: 255, B: 255, A: 255}
	return style.Layout(gtx)
}

func statusLabel(theme *material.Theme, status string) layout.Widget {
	style := material.Label(theme, unit.Sp(13), status)
	style.Color = theme.Palette.Fg
	if color, ok := map[string]color.NRGBA{
		"运行中":        {R: 24, G: 125, B: 78, A: 255},
		"启动中":        {R: 175, G: 105, B: 0, A: 255},
		"停止中":        {R: 175, G: 105, B: 0, A: 255},
		"启动失败":       {R: 188, G: 51, B: 51, A: 255},
		"运行中（调试不可用）": {R: 175, G: 105, B: 0, A: 255},
		"外部已关联":      {R: 146, G: 93, B: 0, A: 255},
		"外部占用":       {R: 190, G: 75, B: 35, A: 255},
		"未知占用":       {R: 190, G: 75, B: 35, A: 255},
		"已退出":        {R: 100, G: 105, B: 115, A: 255},
	}[status]; ok {
		style.Color = color
	}
	return style.Layout
}

func (s *Shell) settings(gtx layout.Context) layout.Dimensions {
	for s.chromePick.Clicked(gtx) {
		s.pathFeedback = "请选择 Chrome 可执行文件"
	}
	for s.chromeSearch.Clicked(gtx) {
		s.togglePathSearch(PathChromeExecutable)
	}
	for s.edgePick.Clicked(gtx) {
		s.pathFeedback = "请选择 Edge 可执行文件"
	}
	for s.edgeSearch.Clicked(gtx) {
		s.togglePathSearch(PathEdgeExecutable)
	}
	for s.dataPick.Clicked(gtx) {
		s.pathFeedback = "请选择默认 User Data Dir"
	}
	for s.dataSearch.Clicked(gtx) {
		s.togglePathSearch(PathDefaultUserData)
	}
	for s.logPick.Clicked(gtx) {
		s.pathFeedback = "请选择日志目录"
	}
	for s.logSearch.Clicked(gtx) {
		s.togglePathSearch(PathLogDirectory)
	}
	for s.proxySave.Clicked(gtx) {
		s.saveProxy()
	}
	for s.proxyDelete.Clicked(gtx) {
		s.requestProxyDelete()
	}
	for s.saveClick.Clicked(gtx) {
		settings, err := s.settingsState()
		if err != nil {
			s.pathFeedback = err.Error()
			continue
		}
		s.remoteDebugPort.SetText(strconv.Itoa(settings.RemoteDebugStartPort))
		if s.onSave != nil {
			s.onSave(settings)
		}
	}
	for s.cancelClick.Clicked(gtx) {
		s.resetSettings()
	}
	return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
		layout.Rigid(material.H4(s.theme, "设置").Layout),
		layout.Rigid(material.Body1(s.theme, "配置浏览器可执行文件、默认目录和本地运行行为").Layout),
		layout.Rigid(layout.Spacer{Height: unit.Dp(18)}.Layout),
		layout.Rigid(s.pathField(PathChromeExecutable, "Chrome 可执行文件", &s.chromePath, &s.chromePick, &s.chromeSearch)),
		layout.Rigid(layout.Spacer{Height: unit.Dp(10)}.Layout),
		layout.Rigid(s.pathField(PathEdgeExecutable, "Edge 可执行文件", &s.edgePath, &s.edgePick, &s.edgeSearch)),
		layout.Rigid(layout.Spacer{Height: unit.Dp(10)}.Layout),
		layout.Rigid(s.pathField(PathDefaultUserData, "默认 User Data Dir", &s.dataDir, &s.dataPick, &s.dataSearch)),
		layout.Rigid(layout.Spacer{Height: unit.Dp(10)}.Layout),
		layout.Rigid(s.pathField(PathLogDirectory, "日志目录", &s.logDir, &s.logPick, &s.logSearch)),
		layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
		layout.Rigid(s.remoteDebugPortField),
		layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
		layout.Rigid(material.Caption(s.theme, s.pathFeedback).Layout),
		layout.Rigid(layout.Spacer{Height: unit.Dp(10)}.Layout),
		layout.Rigid(material.CheckBox(s.theme, &s.closeOnExit, "退出时关闭托管浏览器").Layout),
		layout.Rigid(layout.Spacer{Height: unit.Dp(16)}.Layout),
		layout.Rigid(s.proxySettings),
		layout.Rigid(layout.Spacer{Height: unit.Dp(16)}.Layout),
		layout.Rigid(func(gtx layout.Context) layout.Dimensions {
			return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
				layout.Rigid(material.Button(s.theme, &s.saveClick, "保存设置").Layout),
				layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
				layout.Rigid(material.Button(s.theme, &s.cancelClick, "取消").Layout),
			)
		}),
	)
}

func (s *Shell) proxySettings(gtx layout.Context) layout.Dimensions {
	return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
		layout.Rigid(material.H6(s.theme, "代理").Layout),
		layout.Rigid(material.Caption(s.theme, "仅保存无认证 scheme://host:port 端点；下拉框和实例表单显示完整地址。").Layout),
		layout.Rigid(layout.Spacer{Height: unit.Dp(8)}.Layout),
		layout.Rigid(func(gtx layout.Context) layout.Dimensions { return s.proxyPickerField(gtx, proxyPickerSettings) }),
		layout.Rigid(layout.Spacer{Height: unit.Dp(8)}.Layout),
		layout.Rigid(s.formField("代理地址", "支持 http、https、socks4、socks5；不允许用户名、密码或路径", &s.proxyServer)),
		layout.Rigid(layout.Spacer{Height: unit.Dp(8)}.Layout),
		layout.Rigid(func(gtx layout.Context) layout.Dimensions {
			return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
				layout.Rigid(material.Button(s.theme, &s.proxySave, "保存代理").Layout),
				layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
				layout.Rigid(s.proxyDeleteButton),
			)
		}),
		layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
		layout.Rigid(material.Caption(s.theme, s.proxyFeedback).Layout),
	)
}

func (s *Shell) proxyDeleteButton(gtx layout.Context) layout.Dimensions {
	buttonGtx := gtx
	if s.settingsProxyID == "" {
		buttonGtx = gtx.Disabled()
	}
	style := material.Button(s.theme, &s.proxyDelete, "删除代理")
	style.Background = color.NRGBA{R: 188, G: 51, B: 51, A: 255}
	style.Color = color.NRGBA{R: 255, G: 255, B: 255, A: 255}
	return style.Layout(buttonGtx)
}

func (s *Shell) remoteDebugPortField(gtx layout.Context) layout.Dimensions {
	return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
		layout.Rigid(material.Body2(s.theme, "远程调试起始端口").Layout),
		layout.Rigid(material.Caption(s.theme, "留空时使用 9666；仅绑定 127.0.0.1，启动时顺序尝试下一个可用端口").Layout),
		layout.Rigid(layout.Spacer{Height: unit.Dp(4)}.Layout),
		layout.Rigid(material.Editor(s.theme, &s.remoteDebugPort, "例如：9666").Layout),
	)
}

func (s *Shell) pathField(field PathField, label string, editor *widget.Editor, pick, search *widget.Clickable) layout.Widget {
	return func(gtx layout.Context) layout.Dimensions {
		return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
			layout.Rigid(func(gtx layout.Context) layout.Dimensions {
				return layout.Inset{Right: unit.Dp(12)}.Layout(gtx, material.Body2(s.theme, label).Layout)
			}),
			layout.Flexed(1, material.Editor(s.theme, editor, "请输入或粘贴路径").Layout),
			layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
			layout.Rigid(material.Button(s.theme, pick, "选择").Layout),
			layout.Rigid(layout.Spacer{Width: unit.Dp(6)}.Layout),
			layout.Rigid(material.Button(s.theme, search, s.searchButtonLabel(field)).Layout),
		)
	}
}

func (s *Shell) createInstance(gtx layout.Context) layout.Dimensions {
	return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
		layout.Rigid(material.H4(s.theme, "新建实例").Layout),
		layout.Rigid(material.Body1(s.theme, "为一个独立的 Chrome 或 Edge User Data Dir 创建托管实例").Layout),
		layout.Rigid(layout.Spacer{Height: unit.Dp(18)}.Layout),
		layout.Rigid(s.formField("实例名称", "用于在实例列表中识别此浏览器环境", &s.instanceName)),
		layout.Rigid(layout.Spacer{Height: unit.Dp(10)}.Layout),
		layout.Rigid(s.instanceDirField),
		layout.Rigid(layout.Spacer{Height: unit.Dp(10)}.Layout),
		layout.Rigid(s.formField("启动 URL（可选）", "仅支持 http/https；留空时启动浏览器默认页", &s.instanceURL)),
		layout.Rigid(layout.Spacer{Height: unit.Dp(14)}.Layout),
		layout.Rigid(func(gtx layout.Context) layout.Dimensions { return s.proxyPickerField(gtx, proxyPickerCreate) }),
		layout.Rigid(layout.Spacer{Height: unit.Dp(14)}.Layout),
		layout.Rigid(material.Body2(s.theme, "浏览器类型").Layout),
		layout.Rigid(func(gtx layout.Context) layout.Dimensions {
			return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
				layout.Rigid(material.RadioButton(s.theme, &s.browserKind, "chrome", "Chrome").Layout),
				layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
				layout.Rigid(material.RadioButton(s.theme, &s.browserKind, "edge", "Edge").Layout),
			)
		}),
		layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
		layout.Rigid(material.Caption(s.theme, s.formFeedback).Layout),
		layout.Rigid(layout.Spacer{Height: unit.Dp(18)}.Layout),
		layout.Rigid(func(gtx layout.Context) layout.Dimensions {
			return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
				layout.Rigid(material.Button(s.theme, &s.createClick, "创建实例").Layout),
				layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
				layout.Rigid(material.Button(s.theme, &s.backClick, "取消").Layout),
			)
		}),
	)
}

func (s *Shell) formField(label, help string, editor *widget.Editor) layout.Widget {
	return func(gtx layout.Context) layout.Dimensions {
		return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
			layout.Rigid(material.Body2(s.theme, label).Layout),
			layout.Rigid(material.Caption(s.theme, help).Layout),
			layout.Rigid(layout.Spacer{Height: unit.Dp(4)}.Layout),
			layout.Rigid(material.Editor(s.theme, editor, "请输入").Layout),
		)
	}
}

func (s *Shell) proxyPickerField(gtx layout.Context, target proxyPickerTarget) layout.Dimensions {
	click := &s.createProxyPick
	selected := s.createProxyID
	label := "代理"
	help := "选择设置中保存的无认证代理；留空表示不使用代理"
	if target == proxyPickerEdit {
		click = &s.editProxyPick
		selected = s.editProxyID
	} else if target == proxyPickerSettings {
		click = &s.settingsProxyPick
		selected = s.settingsProxyID
		label = "已保存代理"
		help = "选择项会回填代理地址；选择新建会清空输入框"
	}
	for click.Clicked(gtx) {
		s.proxyPicker = proxyPickerState{open: true, target: target}
	}
	return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
		layout.Rigid(material.Body2(s.theme, label).Layout),
		layout.Rigid(material.Caption(s.theme, help).Layout),
		layout.Rigid(layout.Spacer{Height: unit.Dp(4)}.Layout),
		layout.Rigid(material.Button(s.theme, click, s.proxyLabel(selected)).Layout),
	)
}

func (s *Shell) proxyLabel(id string) string {
	if id == "" {
		return "无代理"
	}
	for _, option := range s.proxies {
		if option.ID == id {
			return option.Server
		}
	}
	return "代理不可用"
}

func (s *Shell) proxyExists(id string) bool {
	if _, exists := s.proxyOption(id); exists {
		return true
	}
	return id == ""
}

func (s *Shell) proxyOption(id string) (ProxyOption, bool) {
	if id == "" {
		return ProxyOption{}, false
	}
	for _, option := range s.proxies {
		if option.ID == id {
			return option, true
		}
	}
	return ProxyOption{}, false
}

func (s *Shell) proxyPickerChoiceFor(id string) *widget.Clickable {
	if click := s.proxyPickerChoices[id]; click != nil {
		return click
	}
	click := new(widget.Clickable)
	s.proxyPickerChoices[id] = click
	return click
}

func (s *Shell) selectPickerProxy(id string) {
	if !s.proxyExists(id) {
		return
	}
	if s.proxyPicker.target == proxyPickerEdit {
		s.editProxyID = id
	} else if s.proxyPicker.target == proxyPickerSettings {
		s.settingsProxyID = id
		if id == "" {
			s.proxyServer.SetText("")
		} else {
			for _, option := range s.proxies {
				if option.ID == id {
					s.proxyServer.SetText(option.Server)
					break
				}
			}
		}
		s.proxyFeedback = ""
	} else {
		s.createProxyID = id
	}
	s.proxyPicker.open = false
}

func (s *Shell) proxyPickerDialog(gtx layout.Context) layout.Dimensions {
	if !s.proxyPicker.open {
		return layout.Dimensions{}
	}
	gtx.Constraints.Min = gtx.Constraints.Max
	return s.proxyPickerBlocker.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
		defer clip.Rect{Max: gtx.Constraints.Min}.Push(gtx.Ops).Pop()
		paint.Fill(gtx.Ops, color.NRGBA{R: 0, G: 0, B: 0, A: 92})
		for s.proxyPickerBlocker.Clicked(gtx) {
			s.proxyPicker.open = false
		}
		for s.proxyPickerNone.Clicked(gtx) {
			s.selectPickerProxy("")
		}
		for _, option := range append([]ProxyOption(nil), s.proxies...) {
			for s.proxyPickerChoiceFor(option.ID).Clicked(gtx) {
				s.selectPickerProxy(option.ID)
			}
		}
		return layout.Center.Layout(gtx, s.proxyPickerCard)
	})
}

func (s *Shell) proxyPickerCard(gtx layout.Context) layout.Dimensions {
	if maxWidth := gtx.Dp(440); gtx.Constraints.Max.X > maxWidth {
		gtx.Constraints.Max.X = maxWidth
	}
	return layout.Background{}.Layout(gtx,
		func(gtx layout.Context) layout.Dimensions {
			rect := image.Rectangle{Max: gtx.Constraints.Min}
			defer clip.UniformRRect(rect, gtx.Dp(8)).Push(gtx.Ops).Pop()
			paint.Fill(gtx.Ops, s.theme.Palette.Bg)
			return layout.Dimensions{Size: gtx.Constraints.Min}
		},
		func(gtx layout.Context) layout.Dimensions {
			return layout.Inset{Top: unit.Dp(20), Right: unit.Dp(24), Bottom: unit.Dp(20), Left: unit.Dp(24)}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
				children := []layout.FlexChild{
					layout.Rigid(material.H6(s.theme, s.proxyPickerTitle()).Layout),
					layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
					layout.Rigid(material.Caption(s.theme, "仅显示和使用无认证代理端点。按 Escape 或点击背景取消。").Layout),
					layout.Rigid(layout.Spacer{Height: unit.Dp(12)}.Layout),
					layout.Rigid(material.Button(s.theme, &s.proxyPickerNone, s.proxyPickerNoneLabel()).Layout),
				}
				for _, option := range s.proxies {
					option := option
					children = append(children,
						layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
						layout.Rigid(func(gtx layout.Context) layout.Dimensions {
							return s.proxyPickerChoiceFor(option.ID).Layout(gtx, func(gtx layout.Context) layout.Dimensions {
								return layout.Inset{Top: unit.Dp(7), Bottom: unit.Dp(7), Left: unit.Dp(10), Right: unit.Dp(10)}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
									return material.Body1(s.theme, option.Server).Layout(gtx)
								})
							})
						}),
					)
				}
				return layout.Flex{Axis: layout.Vertical}.Layout(gtx, children...)
			})
		},
	)
}

func (s *Shell) proxyPickerTitle() string {
	if s.proxyPicker.target == proxyPickerSettings {
		return "选择已保存代理"
	}
	return "选择代理"
}

func (s *Shell) proxyPickerNoneLabel() string {
	if s.proxyPicker.target == proxyPickerSettings {
		return "新建代理（不选择）"
	}
	return "无代理"
}

func (s *Shell) instanceDirField(gtx layout.Context) layout.Dimensions {
	return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
		layout.Rigid(material.Body2(s.theme, "User Data Dir").Layout),
		layout.Rigid(material.Caption(s.theme, "浏览器独立数据目录；必须是绝对路径").Layout),
		layout.Rigid(layout.Spacer{Height: unit.Dp(4)}.Layout),
		layout.Rigid(func(gtx layout.Context) layout.Dimensions {
			return layout.Flex{Alignment: layout.Middle}.Layout(gtx,
				layout.Flexed(1, material.Editor(s.theme, &s.instanceDir, "请输入或粘贴绝对路径").Layout),
				layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
				layout.Rigid(material.Button(s.theme, &s.instanceDirPick, s.instanceDirButtonLabel()).Layout),
			)
		}),
	)
}

func (s *Shell) createInstanceFromForm() {
	name := strings.TrimSpace(s.instanceName.Text())
	if name == "" {
		s.formFeedback = "请输入实例名称后再创建。"
		return
	}
	userDataDir := strings.TrimSpace(s.instanceDir.Text())
	if userDataDir == "" {
		s.formFeedback = "请选择或输入 User Data Dir 后再创建。"
		return
	}
	s.nextInstance++
	s.rows = append(s.rows, InstanceRow{
		ID:          fmt.Sprintf("instance-%d", s.nextInstance),
		Name:        name,
		Browser:     browserDisplay(s.browserKind.Value),
		UserDataDir: userDataDir,
		TargetURL:   strings.TrimSpace(s.instanceURL.Text()),
		ProxyID:     s.createProxyID,
		Status:      "已退出",
	})
	s.page = pageInstances
	s.formFeedback = ""
	s.notifyInstancesChanged()
}

func (s *Shell) togglePathSearch(field PathField) {
	state := s.searches[field]
	if state == nil {
		return
	}
	if state.running {
		state.cancel()
		state.cancel = nil
		state.running = false
		state.request++
		s.pathFeedback = fmt.Sprintf("已取消%s搜索。", pathFieldLabel(field))
		return
	}
	if s.pathSearcher == nil {
		s.pathFeedback = fmt.Sprintf("%s搜索服务尚未准备好。", pathFieldLabel(field))
		return
	}
	state.request++
	request := state.request
	ctx, cancel := context.WithCancel(context.Background())
	state.cancel = cancel
	state.running = true
	current := s.pathEditor(field).Text()
	s.pathFeedback = fmt.Sprintf("正在搜索%s…", pathFieldLabel(field))
	go func() {
		path, err := s.pathSearcher(ctx, field, current)
		s.searchResults <- pathSearchResult{field: field, request: request, path: path, err: err}
		if s.invalidate != nil {
			s.invalidate()
		}
	}()
}

func (s *Shell) consumeSearchResults() {
	for {
		select {
		case result := <-s.searchResults:
			state := s.searches[result.field]
			if state == nil || !state.running || result.request != state.request {
				continue
			}
			state.running = false
			state.cancel = nil
			if result.err != nil {
				if errors.Is(result.err, context.Canceled) {
					s.pathFeedback = fmt.Sprintf("已取消%s搜索。", pathFieldLabel(result.field))
				} else {
					s.pathFeedback = fmt.Sprintf("搜索%s失败：%v", pathFieldLabel(result.field), result.err)
				}
				continue
			}
			if result.path == "" {
				s.pathFeedback = fmt.Sprintf("未找到%s。", pathFieldLabel(result.field))
				continue
			}
			s.pathEditor(result.field).SetText(result.path)
			s.pathFeedback = fmt.Sprintf("已找到%s。", pathFieldLabel(result.field))
		default:
			return
		}
	}
}

func (s *Shell) searchButtonLabel(field PathField) string {
	if state := s.searches[field]; state != nil && state.running {
		return "取消"
	}
	return "搜索"
}

func (s *Shell) pathEditor(field PathField) *widget.Editor {
	switch field {
	case PathChromeExecutable:
		return &s.chromePath
	case PathEdgeExecutable:
		return &s.edgePath
	case PathDefaultUserData:
		return &s.dataDir
	default:
		return &s.logDir
	}
}

func pathFieldLabel(field PathField) string {
	switch field {
	case PathChromeExecutable:
		return "Chrome 可执行文件"
	case PathEdgeExecutable:
		return "Edge 可执行文件"
	case PathDefaultUserData:
		return "默认 User Data Dir"
	default:
		return "日志目录"
	}
}

func browserDisplay(value string) string {
	if value == "edge" {
		return "Edge"
	}
	return "Chrome"
}

func (s *Shell) startClickFor(id string) *widget.Clickable {
	if click := s.startClicks[id]; click != nil {
		return click
	}
	click := new(widget.Clickable)
	s.startClicks[id] = click
	return click
}

func (s *Shell) rowClickFor(id string) *widget.Clickable {
	if click := s.rowClicks[id]; click != nil {
		return click
	}
	click := new(widget.Clickable)
	s.rowClicks[id] = click
	return click
}

func (s *Shell) editClickFor(id string) *widget.Clickable {
	if click := s.editClicks[id]; click != nil {
		return click
	}
	click := new(widget.Clickable)
	s.editClicks[id] = click
	return click
}

func (s *Shell) deleteClickFor(id string) *widget.Clickable {
	if click := s.deleteClicks[id]; click != nil {
		return click
	}
	click := new(widget.Clickable)
	s.deleteClicks[id] = click
	return click
}

func (s *Shell) saveProxy() {
	server, err := domain.NormalizeProxyServer(s.proxyServer.Text())
	if err != nil || server == "" {
		s.proxyFeedback = "代理地址必须是无认证的 scheme://host:port。"
		return
	}
	for _, option := range s.proxies {
		if option.ID != s.settingsProxyID && option.Server == server {
			s.proxyFeedback = "该代理地址已存在，请从下拉框选择它。"
			return
		}
	}
	if s.settingsProxyID == "" {
		s.nextProxy++
		s.settingsProxyID = fmt.Sprintf("proxy-%d", s.nextProxy)
		s.proxies = append(s.proxies, ProxyOption{ID: s.settingsProxyID, Name: server, Server: server})
		s.proxyFeedback = fmt.Sprintf("已添加代理“%s”；后续启动将使用该地址。", server)
	} else {
		updated := false
		for index := range s.proxies {
			if s.proxies[index].ID != s.settingsProxyID {
				continue
			}
			s.proxies[index].Name = server
			s.proxies[index].Server = server
			updated = true
			break
		}
		if !updated {
			s.proxyFeedback = "所选代理已不可用，请重新选择或新建。"
			return
		}
		s.proxyFeedback = fmt.Sprintf("已保存代理“%s”；后续启动将使用最新端点。", server)
	}
	s.proxyServer.SetText(server)
	s.notifyProxiesChanged()
}

func (s *Shell) requestProxyDelete() {
	id := s.settingsProxyID
	if id == "" {
		s.proxyFeedback = "请先选择要删除的代理。"
		return
	}
	if count := s.proxyUseCount(id); count > 0 {
		s.proxyFeedback = fmt.Sprintf("该代理仍被 %d 个实例使用，不能删除。", count)
		return
	}
	if _, exists := s.proxyOption(id); !exists {
		s.proxyFeedback = "所选代理已不可用。"
		return
	}
	s.pendingProxyDelete = id
	s.proxyDeleteFocus = true
}

func (s *Shell) cancelProxyDelete() {
	s.pendingProxyDelete = ""
	s.proxyDeleteFocus = false
	s.proxyFeedback = "已取消删除代理。"
}

func (s *Shell) confirmProxyDelete() {
	id := s.pendingProxyDelete
	s.pendingProxyDelete = ""
	s.proxyDeleteFocus = false
	if count := s.proxyUseCount(id); count > 0 {
		s.proxyFeedback = fmt.Sprintf("该代理仍被 %d 个实例使用，不能删除。", count)
		return
	}
	for index, option := range s.proxies {
		if option.ID != id {
			continue
		}
		s.proxies = append(s.proxies[:index], s.proxies[index+1:]...)
		delete(s.proxyPickerChoices, id)
		if s.createProxyID == id {
			s.createProxyID = ""
		}
		if s.editProxyID == id {
			s.editProxyID = ""
		}
		if s.settingsProxyID == id {
			s.settingsProxyID = ""
			s.proxyServer.SetText("")
		}
		s.proxyFeedback = fmt.Sprintf("已删除代理“%s”。", option.Server)
		s.notifyProxiesChanged()
		return
	}
	s.proxyFeedback = "找不到要删除的代理。"
}

func (s *Shell) proxyUseCount(id string) int {
	count := 0
	for _, row := range s.rows {
		if row.ProxyID == id {
			count++
		}
	}
	return count
}

func (s *Shell) notifyProxiesChanged() {
	if s.onProxiesChanged != nil {
		s.onProxiesChanged(append([]ProxyOption(nil), s.proxies...))
	}
}

func (s *Shell) requestInstanceAction(id string) {
	row, ok := s.instanceRow(id)
	if !ok {
		s.instanceFeedback = "找不到要操作的实例。"
		return
	}
	mode := instanceActionFor(row)
	if !mode.enabled {
		s.instanceFeedback = fmt.Sprintf("%s%s，请稍候。", row.Name, mode.label)
		return
	}
	if mode.stop {
		s.requestStop(id)
		return
	}
	s.requestStart(id)
}

func (s *Shell) requestStop(id string) {
	row, ok := s.instanceRow(id)
	if !ok {
		s.instanceFeedback = "找不到要停止的实例。"
		return
	}
	if row.Status != "运行中" && row.Status != "运行中（调试不可用）" {
		s.instanceFeedback = fmt.Sprintf("%s 当前不能由 Chub 停止。", row.Name)
		return
	}
	if row.OccupancySource != "" && row.OccupancySource != "chub_registry" {
		s.instanceFeedback = fmt.Sprintf("%s 不是 Chub 托管实例，不能停止。", row.Name)
		return
	}
	state := s.stopStates[id]
	if state != nil && state.running {
		s.instanceFeedback = fmt.Sprintf("%s 正在停止，请稍候。", row.Name)
		return
	}
	if s.instanceStopper == nil {
		s.instanceFeedback = "浏览器停止服务尚未准备好。"
		return
	}
	if state == nil {
		state = &instanceStopState{}
		s.stopStates[id] = state
	}
	state.request++
	request := state.request
	state.running = true
	state.previousStatus = row.Status
	s.setInstanceStatus(id, "停止中")
	s.instanceFeedback = fmt.Sprintf("正在请求 %s 正常退出…", row.Name)
	go func() {
		err := s.instanceStopper(context.Background(), row)
		s.stopResults <- instanceStopResult{id: id, request: request, err: err}
		if s.invalidate != nil {
			s.invalidate()
		}
	}()
}

func (s *Shell) requestStart(id string) {
	row, ok := s.instanceRow(id)
	if !ok {
		s.instanceFeedback = "找不到要启动的实例。"
		return
	}
	state := s.startStates[id]
	if state != nil && state.running {
		s.instanceFeedback = fmt.Sprintf("%s 正在启动，请稍候。", row.Name)
		return
	}
	if stop := s.stopStates[id]; stop != nil && stop.running {
		s.instanceFeedback = fmt.Sprintf("%s 正在停止，请等待退出后再启动。", row.Name)
		return
	}
	if s.instanceStarter == nil {
		s.instanceFeedback = "浏览器启动服务尚未准备好。"
		return
	}
	settings, err := s.settingsState()
	if err != nil {
		s.instanceFeedback = err.Error()
		return
	}
	if state == nil {
		state = &instanceStartState{}
		s.startStates[id] = state
	}
	state.request++
	request := state.request
	state.running = true
	s.setInstanceStatus(id, "启动中")
	s.instanceFeedback = fmt.Sprintf("正在启动 %s…", row.Name)
	go func() {
		outcome, err := s.instanceStarter(context.Background(), row, settings)
		s.startResults <- instanceStartResult{id: id, request: request, outcome: outcome, err: err}
		if s.invalidate != nil {
			s.invalidate()
		}
	}()
}

func (s *Shell) consumeStopResults() {
	for {
		select {
		case result := <-s.stopResults:
			state := s.stopStates[result.id]
			if state == nil || !state.running || result.request != state.request {
				continue
			}
			state.running = false
			row, exists := s.instanceRow(result.id)
			if !exists {
				continue
			}
			if result.err != nil {
				if row.Status == "停止中" {
					s.setInstanceRuntime(result.id, state.previousStatus, row.PID, row.RemoteDebugPort, row.OccupancySource)
				}
				s.instanceFeedback = fmt.Sprintf("停止 %s 失败：%v", row.Name, result.err)
				continue
			}
			s.setInstanceRuntime(result.id, "已退出", 0, 0, "")
			s.focusRestoreID = result.id
			s.instanceFeedback = fmt.Sprintf("%s 已正常退出。", row.Name)
		default:
			return
		}
	}
}

func (s *Shell) consumeStartResults() {
	for {
		select {
		case result := <-s.startResults:
			state := s.startStates[result.id]
			if state == nil || !state.running || result.request != state.request {
				continue
			}
			state.running = false
			row, exists := s.instanceRow(result.id)
			if !exists {
				continue
			}
			if result.err != nil {
				if errors.Is(result.err, domain.ErrProfileOccupied) {
					if result.outcome.Source == "chub_registry" {
						s.setInstanceRuntime(result.id, "运行中", result.outcome.PID, result.outcome.RemoteDebugPort, result.outcome.Source)
						s.instanceFeedback = fmt.Sprintf("%s 已由 Chub 启动，未重复创建浏览器。", row.Name)
					} else {
						s.setInstanceRuntime(result.id, "外部占用", result.outcome.PID, result.outcome.RemoteDebugPort, result.outcome.Source)
						s.instanceFeedback = fmt.Sprintf("%s 的 User Data Dir 已被外部浏览器占用，未再次启动。", row.Name)
					}
				} else {
					s.setInstanceStatus(result.id, "启动失败")
					s.instanceFeedback = fmt.Sprintf("启动 %s 失败：%v", row.Name, result.err)
				}
				continue
			}
			if result.outcome.External {
				s.setInstanceRuntime(result.id, "外部已关联", result.outcome.PID, result.outcome.RemoteDebugPort, result.outcome.Source)
				s.instanceFeedback = fmt.Sprintf("已关联外部 %s（PID %d，端口 %d）；不会接管其生命周期。", row.Name, result.outcome.PID, result.outcome.RemoteDebugPort)
				continue
			}
			status := "运行中"
			if result.outcome.Warning != "" {
				status = "运行中（调试不可用）"
			}
			s.setInstanceRuntime(result.id, status, result.outcome.PID, result.outcome.RemoteDebugPort, "chub_registry")
			if result.outcome.Warning != "" {
				s.instanceFeedback = fmt.Sprintf("%s 已启动（PID %d），但%s。", row.Name, result.outcome.PID, result.outcome.Warning)
			} else {
				s.instanceFeedback = fmt.Sprintf("已启动 %s（PID %d，端口 %d）。", row.Name, result.outcome.PID, result.outcome.RemoteDebugPort)
			}
		default:
			return
		}
	}
}

func (s *Shell) requestRefresh() {
	if s.refreshClickState.running {
		s.instanceFeedback = "实例状态正在刷新，请稍候。"
		return
	}
	if s.instanceRefresher == nil {
		s.instanceFeedback = "实例状态刷新服务尚未准备好。"
		return
	}
	rows := append([]InstanceRow(nil), s.rows...)
	snapshots := make(map[string]string, len(rows))
	for _, row := range rows {
		snapshots[row.ID] = instanceRefreshFingerprint(row)
	}
	s.refreshClickState.request++
	request := s.refreshClickState.request
	s.refreshClickState.running = true
	s.instanceFeedback = "正在刷新已保存实例的状态…"
	go func() {
		results, err := s.instanceRefresher(context.Background(), rows)
		s.refreshResults <- instanceRefreshResult{request: request, snapshots: snapshots, results: results, err: err}
		if s.invalidate != nil {
			s.invalidate()
		}
	}()
}

func (s *Shell) consumeRefreshResults() {
	for {
		select {
		case result := <-s.refreshResults:
			if !s.refreshClickState.running || result.request != s.refreshClickState.request {
				continue
			}
			s.refreshClickState.running = false
			if result.err != nil {
				s.instanceFeedback = fmt.Sprintf("刷新实例状态失败：%v", result.err)
				continue
			}
			applied, skipped, failed := 0, 0, 0
			for _, refreshed := range result.results {
				row, exists := s.instanceRow(refreshed.ID)
				if !exists || result.snapshots[refreshed.ID] != instanceRefreshFingerprint(row) {
					skipped++
					continue
				}
				if refreshed.Status == "" {
					failed++
					continue
				}
				s.setInstanceRuntime(refreshed.ID, refreshed.Status, refreshed.PID, refreshed.RemoteDebugPort, refreshed.OccupancySource)
				if refreshed.Message != "" {
					failed++
				}
				applied++
			}
			switch {
			case applied == 0 && failed > 0:
				s.instanceFeedback = "实例状态刷新完成，但部分实例无法确认，请查看状态后重试。"
			case skipped > 0:
				s.instanceFeedback = fmt.Sprintf("已刷新 %d 个实例；忽略 %d 个已编辑或删除记录的过期结果。", applied, skipped)
			case failed > 0:
				s.instanceFeedback = fmt.Sprintf("已刷新 %d 个实例；%d 个实例状态无法完全确认。", applied, failed)
			default:
				s.instanceFeedback = fmt.Sprintf("已刷新 %d 个已保存实例的状态。", applied)
			}
		default:
			return
		}
	}
}

func instanceRefreshFingerprint(row InstanceRow) string {
	return strings.Join([]string{row.ID, row.Name, row.Browser, row.UserDataDir, row.TargetURL, row.ProxyID}, "\x00")
}

func (s *Shell) requestDelete(id string) {
	row, ok := s.instanceRow(id)
	if !ok {
		s.instanceFeedback = "找不到要删除的实例。"
		return
	}
	if state := s.startStates[id]; state != nil && state.running {
		s.instanceFeedback = fmt.Sprintf("%s 正在启动，暂时不能删除。", row.Name)
		return
	}
	if state := s.stopStates[id]; state != nil && state.running {
		s.instanceFeedback = fmt.Sprintf("%s 正在停止，暂时不能删除。", row.Name)
		return
	}
	s.pendingDeleteID = id
}

func (s *Shell) consumeDeleteConfirmation(gtx layout.Context) {
	for s.deleteBlocker.Clicked(gtx) {
	}
	for s.deleteCancel.Clicked(gtx) {
		s.cancelDelete()
	}
	for s.deleteConfirm.Clicked(gtx) {
		s.confirmDelete()
	}
}

func (s *Shell) consumeProxyDeleteConfirmation(gtx layout.Context) {
	for s.proxyDeleteBlocker.Clicked(gtx) {
	}
	for s.proxyDeleteCancel.Clicked(gtx) {
		s.cancelProxyDelete()
	}
	for s.proxyDeleteConfirm.Clicked(gtx) {
		s.confirmProxyDelete()
	}
}

func (s *Shell) cancelDelete() {
	if row, ok := s.instanceRow(s.pendingDeleteID); ok {
		s.instanceFeedback = fmt.Sprintf("已取消删除实例“%s”。", row.Name)
	}
	s.pendingDeleteID = ""
}

func (s *Shell) confirmDelete() {
	id := s.pendingDeleteID
	s.pendingDeleteID = ""
	s.deleteInstance(id)
}

func (s *Shell) deleteInstance(id string) {
	for i, row := range s.rows {
		if row.ID != id {
			continue
		}
		s.rows = append(s.rows[:i], s.rows[i+1:]...)
		delete(s.startClicks, id)
		delete(s.rowClicks, id)
		delete(s.editClicks, id)
		delete(s.deleteClicks, id)
		delete(s.startStates, id)
		delete(s.stopStates, id)
		s.instanceFeedback = fmt.Sprintf("已删除实例“%s”；其 User Data Dir 未被删除。", row.Name)
		s.notifyInstancesChanged()
		return
	}
	s.instanceFeedback = "找不到要删除的实例。"
}

func (s *Shell) instanceRow(id string) (InstanceRow, bool) {
	for _, row := range s.rows {
		if row.ID == id {
			return row, true
		}
	}
	return InstanceRow{}, false
}

func (s *Shell) setInstanceStatus(id, status string) bool {
	for i := range s.rows {
		if s.rows[i].ID == id {
			s.rows[i].Status = status
			return true
		}
	}
	return false
}

func (s *Shell) setInstanceRuntime(id, status string, pid, remoteDebugPort int, source string) bool {
	for i := range s.rows {
		if s.rows[i].ID == id {
			s.rows[i].Status = status
			s.rows[i].PID = pid
			s.rows[i].RemoteDebugPort = remoteDebugPort
			s.rows[i].OccupancySource = source
			return true
		}
	}
	return false
}

func (s *Shell) replaceInstanceRow(updated InstanceRow) bool {
	for i := range s.rows {
		if s.rows[i].ID == updated.ID {
			s.rows[i] = updated
			return true
		}
	}
	return false
}

func (s *Shell) settingsState() (SettingsState, error) {
	port, err := normalizeRemoteDebugStartPort(s.remoteDebugPort.Text())
	if err != nil {
		return SettingsState{}, err
	}
	return SettingsState{
		ChromePath:           s.chromePath.Text(),
		EdgePath:             s.edgePath.Text(),
		DefaultDir:           s.dataDir.Text(),
		LogDir:               s.logDir.Text(),
		RemoteDebugStartPort: port,
		CloseOnExit:          s.closeOnExit.Value,
	}, nil
}

func normalizeRemoteDebugStartPort(value string) (int, error) {
	value = strings.TrimSpace(value)
	if value == "" {
		return domain.DefaultRemoteDebugPort, nil
	}
	port, err := strconv.Atoi(value)
	if err != nil || !domain.ValidRemoteDebugPort(port) {
		return 0, fmt.Errorf("远程调试起始端口必须在 %d 到 %d 之间", domain.MinRemoteDebugPort, domain.MaxRemoteDebugPort)
	}
	return port, nil
}

func (s *Shell) notifyInstancesChanged() {
	if s.onInstancesChanged != nil {
		s.onInstancesChanged(append([]InstanceRow(nil), s.rows...))
	}
}

func mustIcon(data []byte) *widget.Icon {
	icon, err := widget.NewIcon(data)
	if err != nil {
		panic(err)
	}
	return icon
}

func (s *Shell) chooseInstanceDirectory() {
	s.chooseDirectory(directoryPickCreate)
}

func (s *Shell) chooseDirectory(target directoryPickTarget) {
	if s.directoryPick.running {
		if target == directoryPickEdit {
			s.editFeedback = "目录选择器已打开，请在系统窗口中选择或取消。"
		} else {
			s.formFeedback = "目录选择器已打开，请在系统窗口中选择或取消。"
		}
		return
	}
	if s.directoryChooser == nil {
		if target == directoryPickEdit {
			s.editFeedback = "目录选择器尚未准备好。"
		} else {
			s.formFeedback = "目录选择器尚未准备好。"
		}
		return
	}
	s.directoryPick.request++
	request := s.directoryPick.request
	ctx, cancel := context.WithCancel(context.Background())
	s.directoryPick.cancel = cancel
	s.directoryPick.running = true
	s.directoryPick.target = target
	if target == directoryPickEdit {
		s.editFeedback = "正在打开目录选择器…"
	} else {
		s.formFeedback = "正在打开目录选择器…"
	}
	go func() {
		path, err := s.directoryChooser(ctx)
		s.directoryResults <- directoryPickResult{request: request, path: path, err: err}
		if s.invalidate != nil {
			s.invalidate()
		}
	}()
}

func (s *Shell) consumeDirectoryResults() {
	for {
		select {
		case result := <-s.directoryResults:
			if !s.directoryPick.running || result.request != s.directoryPick.request {
				continue
			}
			target := s.directoryPick.target
			s.directoryPick.running = false
			s.directoryPick.cancel = nil
			if result.err != nil {
				if errors.Is(result.err, context.Canceled) {
					s.setDirectoryPickFeedback(target, "已取消选择 User Data Dir。")
				} else {
					s.setDirectoryPickFeedback(target, fmt.Sprintf("选择 User Data Dir 失败：%v", result.err))
				}
				continue
			}
			if result.path == "" {
				s.setDirectoryPickFeedback(target, "未选择 User Data Dir。")
				continue
			}
			if target == directoryPickEdit {
				s.editDir.SetText(result.path)
			} else {
				s.instanceDir.SetText(result.path)
			}
			s.setDirectoryPickFeedback(target, "已更新 User Data Dir。")
		default:
			return
		}
	}
}

func (s *Shell) setDirectoryPickFeedback(target directoryPickTarget, message string) {
	if target == directoryPickEdit {
		s.editFeedback = message
		return
	}
	s.formFeedback = message
}

func (s *Shell) instanceDirButtonLabel() string {
	if s.directoryPick.running {
		return "选择中…"
	}
	return "选择路径"
}

func (s *Shell) resetSettings() {
	s.chromePath.SetText(`C:\Program Files\Google\Chrome\Application\chrome.exe`)
	s.edgePath.SetText(`C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe`)
	s.dataDir.SetText(`C:\Users\Public\chub\profiles`)
	s.logDir.SetText(`C:\Users\Public\chub\logs`)
	s.remoteDebugPort.SetText(strconv.Itoa(domain.DefaultRemoteDebugPort))
}