package ui

import (
	"fmt"
	"strings"

	"github.com/lxn/walk"
	d "github.com/lxn/walk/declarative"
	"github.com/lxn/win"

	"silverpose/v2/internal/alert"
	"silverpose/v2/internal/fall"
	"silverpose/v2/internal/monitor"
)

type Settings struct {
	SourceEnvironment string
	ModelSHA256       string
	RuntimeSummary    string
	EventSummary      string
}

type Commands struct {
	Start func()
	Stop  func()
}

// Window is an observer of monitor updates. It does not own a stream, runtime,
// fall engine, or event artifact writer.
type Window struct {
	main            *walk.MainWindow
	imageView       *walk.ImageView
	connectionLabel *walk.TextLabel
	stateLabel      *walk.TextLabel
	eventLabel      *walk.TextLabel
	startButton     *walk.PushButton
	stopButton      *walk.PushButton
	model           ViewModel
	bitmap          *walk.Bitmap
	seenAlerts      map[string]struct{}
	commands        Commands
}

func NewWindow(settings Settings, commands Commands) (*Window, error) {
	spec := MonitorWindowSpec()
	window := &Window{model: NewViewModel(), seenAlerts: make(map[string]struct{}), commands: commands}
	window.model.SetSourceReady(settings.SourceEnvironment, settings.SourceEnvironment != "")
	background := d.SolidColorBrush{Color: walk.RGB(234, 241, 248)}
	surface := d.SolidColorBrush{Color: walk.RGB(255, 255, 255)}
	if err := (d.MainWindow{
		AssignTo:   &window.main,
		Title:      spec.Title,
		Size:       d.Size{Width: spec.Width, Height: spec.Height},
		MinSize:    d.Size{Width: 960, Height: 640},
		Background: background,
		Layout:     d.VBox{},
		Children: []d.Widget{
			d.TabWidget{
				Pages: []d.TabPage{
					{
						Title:  "监控",
						Layout: d.HBox{},
						Children: []d.Widget{
							d.Composite{
								Background:    surface,
								Layout:        d.VBox{},
								StretchFactor: 3,
								Children: []d.Widget{
									d.TextLabel{Text: "实时画面", ToolTipText: "显示完成推理与姿态叠加后的最新画面"},
									d.ImageView{AssignTo: &window.imageView, Mode: d.ImageViewModeZoom, StretchFactor: 8, ToolTipText: "实时姿态画面"},
								},
							},
							d.Composite{
								Background:    surface,
								Layout:        d.VBox{},
								StretchFactor: 2,
								Children: []d.Widget{
									d.TextLabel{Text: "运行状态"},
									d.TextLabel{AssignTo: &window.connectionLabel, Text: window.model.ConnectionText},
									d.TextLabel{AssignTo: &window.stateLabel, Text: window.model.StateText},
									d.TextLabel{AssignTo: &window.eventLabel, Text: window.model.EventText},
									d.PushButton{AssignTo: &window.startButton, Text: "开始监控", ToolTipText: "使用当前配置启动单路监控", OnClicked: window.start},
									d.PushButton{AssignTo: &window.stopButton, Text: "停止监控", Enabled: false, ToolTipText: "停止监控并释放本地运行资源", OnClicked: window.stop},
									d.TextLabel{Text: "红色仅表示已确认摔倒。连接异常不会触发报警。"},
								},
							},
						},
					},
					{
						Title:  "设置",
						Layout: d.VBox{},
						Children: []d.Widget{
							d.TextLabel{Text: "来源与运行依赖（只读，不显示 RTSP 地址或密码）"},
							d.TextLabel{Text: window.model.SettingsSummary},
							d.TextLabel{Text: "模型 SHA-256：" + shortHash(settings.ModelSHA256)},
							d.TextLabel{Text: "运行依赖：" + settings.RuntimeSummary},
							d.TextLabel{Text: "事件参数：" + settings.EventSummary},
							d.TextLabel{Text: "参数在配置文件中维护；修改后请停止并重新开始监控。"},
						},
					},
				},
			},
		},
	}).Create(); err != nil {
		return nil, err
	}
	window.main.Closing().Attach(func(canceled *bool, reason walk.CloseReason) {
		window.stop()
		if window.bitmap != nil {
			window.bitmap.Dispose()
			window.bitmap = nil
		}
	})
	return window, nil
}

func (window *Window) Run() int { return window.main.Run() }

func (window *Window) start() {
	if window.commands.Start != nil {
		window.commands.Start()
	}
	window.startButton.SetEnabled(false)
	window.stopButton.SetEnabled(true)
}

func (window *Window) stop() {
	if window.commands.Stop != nil {
		window.commands.Stop()
	}
	if window.startButton != nil {
		window.startButton.SetEnabled(true)
	}
	if window.stopButton != nil {
		window.stopButton.SetEnabled(false)
	}
}

// Present runs only the final state assignment on the UI thread.
func (window *Window) Present(update monitor.Update) {
	window.main.Synchronize(func() {
		state := highestState(update.Result)
		window.model.Apply(state, update.SourceStatus)
		if update.SourceMessage != "" {
			window.model.ConnectionText = "视频流：" + update.SourceMessage
		}
		_ = window.connectionLabel.SetText(window.model.ConnectionText)
		_ = window.stateLabel.SetText(window.model.StateText)
		_ = window.eventLabel.SetText(window.model.EventText)
		if update.Image == nil {
			return
		}
		bitmap, err := walk.NewBitmapFromImage(update.Image)
		if err != nil {
			return
		}
		if err := window.imageView.SetImage(bitmap); err != nil {
			bitmap.Dispose()
			return
		}
		previous := window.bitmap
		window.bitmap = bitmap
		if previous != nil {
			previous.Dispose()
		}
	})
}

// PresentAlert is called by a consumer of Monitor.Alerts. Event IDs are checked
// again at the UI boundary so a reconnect/repaint cannot replay sound or popup.
func (window *Window) PresentAlert(record alert.Record) {
	if !record.Written {
		return
	}
	window.main.Synchronize(func() {
		if _, seen := window.seenAlerts[record.Event.EventID]; seen {
			return
		}
		window.seenAlerts[record.Event.EventID] = struct{}{}
		win.MessageBeep(win.MB_ICONHAND)
		message := fmt.Sprintf("确认摔倒\n人员：%s\n延迟：%.2f 秒\n截图：%s", record.Event.TrackID, record.Event.LatencySeconds, record.ScreenshotPath)
		walk.MsgBox(window.main, "Silver Pose V2 · 确认摔倒", message, walk.MsgBoxOK|walk.MsgBoxIconError)
	})
}

// ReportIssue communicates a recoverable startup/worker issue without using
// critical-red fall language or exposing configuration values.
func (window *Window) ReportIssue(message string) {
	window.main.Synchronize(func() {
		window.model.ConnectionText = "视频流：" + message
		window.model.Critical = false
		_ = window.connectionLabel.SetText(window.model.ConnectionText)
		_ = window.stateLabel.SetText("检测状态：正常")
	})
}

func highestState(result fall.FrameResult) fall.State {
	state := fall.Normal
	for _, person := range result.People {
		switch person.State {
		case fall.Confirmed:
			return fall.Confirmed
		case fall.Suspect:
			if state == fall.Normal || state == fall.Recovering {
				state = fall.Suspect
			}
		case fall.Recovering:
			if state == fall.Normal {
				state = fall.Recovering
			}
		}
	}
	return state
}

func shortHash(value string) string {
	if len(value) <= 12 {
		return value
	}
	return strings.ToLower(value[:12]) + "…"
}