package gio

import (
	"fmt"
	"image"
	"image/color"

	"gioui.org/io/semantic"
	"gioui.org/layout"
	"gioui.org/unit"
	"gioui.org/widget"
	"gioui.org/widget/material"

	"softbox.local/core/application"
)

type rowControls struct {
	open widget.Clickable
}

func (shell *AppShell) layoutContent(
	gtx layout.Context,
	theme *material.Theme,
) layout.Dimensions {
	return layout.Flex{}.Layout(
		gtx,
		layout.Rigid(func(gtx layout.Context) layout.Dimensions {
			width := gtx.Dp(unit.Dp(152))
			gtx.Constraints.Min.X = width
			gtx.Constraints.Max.X = width
			return panel(
				gtx,
				shellColors.muted,
				unit.Dp(6),
				layout.UniformInset(unit.Dp(10)),
				func(gtx layout.Context) layout.Dimensions {
					return layout.Flex{Axis: layout.Vertical}.Layout(
						gtx,
						layout.Rigid(func(gtx layout.Context) layout.Dimensions {
							return shell.layoutViewButton(
								gtx,
								theme,
								&shell.viewAll,
								"全部软件",
								application.CatalogViewAll,
							)
						}),
						layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
						layout.Rigid(func(gtx layout.Context) layout.Dimensions {
							return shell.layoutViewButton(
								gtx,
								theme,
								&shell.viewInstalled,
								"已安装",
								application.CatalogViewInstalled,
							)
						}),
						layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
						layout.Rigid(func(gtx layout.Context) layout.Dimensions {
							return shell.layoutViewButton(
								gtx,
								theme,
								&shell.viewUpdates,
								"可更新",
								application.CatalogViewUpdates,
							)
						}),
					)
				},
			)
		}),
		layout.Rigid(layout.Spacer{Width: unit.Dp(12)}.Layout),
		layout.Flexed(1, func(gtx layout.Context) layout.Dimensions {
			selected, hasSelection := shell.model.SelectedItem()
			return layout.Flex{}.Layout(
				gtx,
				layout.Flexed(1, func(gtx layout.Context) layout.Dimensions {
					return panel(
						gtx,
						shellColors.surface,
						unit.Dp(6),
						layout.UniformInset(unit.Dp(12)),
						func(gtx layout.Context) layout.Dimensions {
							visible := shell.model.VisibleItems()
							return layout.Flex{Axis: layout.Vertical}.Layout(
								gtx,
								layout.Rigid(func(gtx layout.Context) layout.Dimensions {
									return layout.Flex{Alignment: layout.Middle}.Layout(
										gtx,
										layout.Rigid(material.H6(theme, viewTitle(shell.model.View())).Layout),
										layout.Flexed(1, layout.Spacer{}.Layout),
										layout.Rigid(func(gtx layout.Context) layout.Dimensions {
											label := material.Caption(
												theme,
												fmt.Sprintf(
													"%d / %d 项",
													len(visible),
													shell.model.TotalCount(),
												),
											)
											label.Color = shellColors.secondary
											return label.Layout(gtx)
										}),
									)
								}),
								layout.Rigid(layout.Spacer{Height: unit.Dp(8)}.Layout),
								layout.Flexed(1, func(gtx layout.Context) layout.Dimensions {
									if len(visible) == 0 {
										return shell.layoutEmptyState(gtx, theme)
									}
									return shell.appList.Layout(gtx, len(visible), func(
										gtx layout.Context,
										index int,
									) layout.Dimensions {
										shell.lastRendered++
										return shell.layoutAppRow(gtx, theme, visible[index])
									})
								}),
							)
						},
					)
				}),
				layout.Rigid(func(gtx layout.Context) layout.Dimensions {
					if !hasSelection {
						return layout.Dimensions{}
					}
					return layout.Spacer{Width: unit.Dp(8)}.Layout(gtx)
				}),
				layout.Rigid(func(gtx layout.Context) layout.Dimensions {
					if !hasSelection {
						return layout.Dimensions{}
					}
					width := gtx.Dp(unit.Dp(280))
					gtx.Constraints.Min.X = width
					gtx.Constraints.Max.X = width
					return shell.layoutDetail(gtx, theme, selected)
				}),
			)
		}),
	)
}

func (shell *AppShell) layoutAppRow(
	gtx layout.Context,
	theme *material.Theme,
	item application.CatalogListItem,
) layout.Dimensions {
	controls := shell.rows[item.ID]
	if controls == nil {
		return layout.Dimensions{}
	}
	return layout.Inset{Bottom: unit.Dp(6)}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
		gtx.Constraints.Min.Y = gtx.Dp(unit.Dp(80))
		return controls.open.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
			semantic.Button.Add(gtx.Ops)
			semantic.DescriptionOp(fmt.Sprintf(
				"%s，版本 %s，状态 %s",
				item.Name,
				item.Version,
				statusLabel(item.Status),
			)).Add(gtx.Ops)
			background := shellColors.muted
			if controls.open.Hovered() || gtx.Focused(&controls.open) {
				background = color.NRGBA{R: 236, G: 253, B: 245, A: 255}
			}
			if shell.model.SelectedID() == item.ID {
				background = color.NRGBA{R: 220, G: 252, B: 231, A: 255}
			}
			return panel(
				gtx,
				background,
				unit.Dp(5),
				layout.UniformInset(unit.Dp(10)),
				func(gtx layout.Context) layout.Dimensions {
					return layout.Flex{Alignment: layout.Middle}.Layout(
						gtx,
						layout.Rigid(func(gtx layout.Context) layout.Dimensions {
							return shell.layoutAppIcon(
								gtx,
								theme,
								item.ID,
								item.Name,
								unit.Dp(40),
								unit.Dp(5),
							)
						}),
						layout.Rigid(layout.Spacer{Width: unit.Dp(10)}.Layout),
						layout.Flexed(1, func(gtx layout.Context) layout.Dimensions {
							return layout.Flex{Axis: layout.Vertical}.Layout(
								gtx,
								layout.Rigid(material.Body1(theme, item.Name).Layout),
								layout.Rigid(layout.Spacer{Height: unit.Dp(3)}.Layout),
								layout.Rigid(func(gtx layout.Context) layout.Dimensions {
									label := material.Caption(
										theme,
										fmt.Sprintf("%s · %s · %s", item.ID, item.Version, item.Category),
									)
									label.Color = shellColors.secondary
									return label.Layout(gtx)
								}),
							)
						}),
						layout.Rigid(layout.Spacer{Width: unit.Dp(8)}.Layout),
						layout.Rigid(func(gtx layout.Context) layout.Dimensions {
							label := material.Body2(theme, statusLabel(item.Status))
							label.Color = statusColor(item.Status)
							return label.Layout(gtx)
						}),
					)
				},
			)
		})
	})
}

func (shell *AppShell) layoutAppIcon(
	gtx layout.Context,
	theme *material.Theme,
	appID string,
	name string,
	iconSize unit.Dp,
	radius unit.Dp,
) layout.Dimensions {
	size := gtx.Dp(iconSize)
	gtx.Constraints.Min = image.Pt(size, size)
	gtx.Constraints.Max = gtx.Constraints.Min
	if icon, exists := shell.icons[appID]; exists {
		return panel(
			gtx,
			shellColors.surface,
			radius,
			layout.UniformInset(unit.Dp(2)),
			func(gtx layout.Context) layout.Dimensions {
				return widget.Image{
					Src:      icon,
					Fit:      widget.Contain,
					Position: layout.Center,
				}.Layout(gtx)
			},
		)
	}
	letter := "S"
	for _, character := range name {
		letter = string(character)
		break
	}
	return panel(
		gtx,
		shellColors.primary,
		radius,
		layout.UniformInset(unit.Dp(0)),
		func(gtx layout.Context) layout.Dimensions {
			return layout.Center.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
				label := material.Body1(theme, letter)
				label.Color = shellColors.onPrimary
				return label.Layout(gtx)
			})
		},
	)
}

func (shell *AppShell) layoutEmptyState(
	gtx layout.Context,
	theme *material.Theme,
) layout.Dimensions {
	return layout.Center.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
		title := "没有匹配的软件"
		body := "清除搜索词、分类或视图筛选后重试。"
		showReset := shell.model.TotalCount() > 0
		if shell.model.TotalCount() == 0 {
			title = "软件目录尚未加载"
			body = "联网刷新或读取已验证缓存后会显示软件。"
			switch shell.catalogState {
			case catalogStateLoading:
				title = "正在加载软件目录"
				body = "正在等待已验证 Catalog 快照。"
			case catalogStateUnconfigured:
				title = "Catalog 来源尚未配置"
				body = "此构建未装配可信发布配置，因此未显示任何软件。"
			case catalogStateLoadFailed:
				title = "Catalog 加载失败"
				body = "未收到可验证的 Catalog；已显示的目录不会被清除。"
			case catalogStateReady:
				title = "Catalog 暂无可显示软件"
				body = "已验证 Catalog 没有适用于当前目标的软件。"
			}
		}
		return layout.Flex{Axis: layout.Vertical, Alignment: layout.Middle}.Layout(
			gtx,
			layout.Rigid(material.H6(theme, title).Layout),
			layout.Rigid(layout.Spacer{Height: unit.Dp(6)}.Layout),
			layout.Rigid(func(gtx layout.Context) layout.Dimensions {
				label := material.Caption(theme, body)
				label.Color = shellColors.secondary
				return label.Layout(gtx)
			}),
			layout.Rigid(func(gtx layout.Context) layout.Dimensions {
				if !showReset {
					return layout.Dimensions{}
				}
				return layout.Inset{Top: unit.Dp(12)}.Layout(gtx, func(gtx layout.Context) layout.Dimensions {
					return shell.layoutFilterButton(
						gtx,
						theme,
						&shell.resetFilters,
						"显示全部软件",
						true,
					)
				})
			}),
		)
	})
}