package ui

import (
	"fmt"
	"image"
	"image/color"
	"strings"
	"time"

	"fyne.io/fyne/v2"
	"fyne.io/fyne/v2/canvas"
	"fyne.io/fyne/v2/container"
	"fyne.io/fyne/v2/layout"
	"fyne.io/fyne/v2/widget"
	"git.leaktechnologies.dev/stu/VideoTools/internal/queue"
	"git.leaktechnologies.dev/stu/VideoTools/internal/utils"
)

// stripedProgress renders a progress bar with a tinted stripe pattern.
type stripedProgress struct {
	widget.BaseWidget
	progress float64
	color    color.Color
	bg       color.Color
	offset   float64
}

func newStripedProgress(col color.Color) *stripedProgress {
	sp := &stripedProgress{
		progress: 0,
		color:    col,
		bg:       color.RGBA{R: 34, G: 38, B: 48, A: 255}, // dark neutral
	}
	sp.ExtendBaseWidget(sp)
	return sp
}

func (s *stripedProgress) SetProgress(p float64) {
	if p < 0 {
		p = 0
	}
	if p > 1 {
		p = 1
	}
	s.progress = p
	s.Refresh()
}

func (s *stripedProgress) CreateRenderer() fyne.WidgetRenderer {
	bgRect := canvas.NewRectangle(s.bg)
	fillRect := canvas.NewRectangle(applyAlpha(s.color, 180))
	stripes := canvas.NewRaster(func(w, h int) image.Image {
		img := image.NewRGBA(image.Rect(0, 0, w, h))
		light := applyAlpha(s.color, 90)
		dark := applyAlpha(s.color, 140)
		for y := 0; y < h; y++ {
			for x := 0; x < w; x++ {
				// animate diagonal stripes using offset
				if (((x + y) + int(s.offset)) / 6 % 2) == 0 {
					img.Set(x, y, light)
				} else {
					img.Set(x, y, dark)
				}
			}
		}
		return img
	})

	objects := []fyne.CanvasObject{bgRect, fillRect, stripes}

	r := &stripedProgressRenderer{
		bar:     s,
		bg:      bgRect,
		fill:    fillRect,
		stripes: stripes,
		objects: objects,
	}
	return r
}

type stripedProgressRenderer struct {
	bar     *stripedProgress
	bg      *canvas.Rectangle
	fill    *canvas.Rectangle
	stripes *canvas.Raster
	objects []fyne.CanvasObject
}

func (r *stripedProgressRenderer) Layout(size fyne.Size) {
	r.bg.Resize(size)
	r.bg.Move(fyne.NewPos(0, 0))

	fillWidth := size.Width * float32(r.bar.progress)
	fillSize := fyne.NewSize(fillWidth, size.Height)

	r.fill.Resize(fillSize)
	r.fill.Move(fyne.NewPos(0, 0))

	r.stripes.Resize(fillSize)
	r.stripes.Move(fyne.NewPos(0, 0))
}

func (r *stripedProgressRenderer) MinSize() fyne.Size {
	return fyne.NewSize(120, 14)
}

func (r *stripedProgressRenderer) Refresh() {
	// small drift to animate stripes
	r.bar.offset += 1
	r.Layout(r.bg.Size())
	canvas.Refresh(r.bg)
}

func (r *stripedProgressRenderer) BackgroundColor() color.Color { return color.Transparent }
func (r *stripedProgressRenderer) Objects() []fyne.CanvasObject { return r.objects }
func (r *stripedProgressRenderer) Destroy()                     {}

func applyAlpha(c color.Color, alpha uint8) color.Color {
	r, g, b, _ := c.RGBA()
	return color.NRGBA{R: uint8(r >> 8), G: uint8(g >> 8), B: uint8(b >> 8), A: alpha}
}

// BuildQueueView creates the queue viewer UI
func BuildQueueView(
	jobs []*queue.Job,
	onBack func(),
	onPause func(string),
	onResume func(string),
	onCancel func(string),
	onRemove func(string),
	onMoveUp func(string),
	onMoveDown func(string),
	onPauseAll func(),
	onResumeAll func(),
	onStart func(),
	onClear func(),
	onClearAll func(),
	onCopyError func(string),
	onViewLog func(string),
	titleColor, bgColor, textColor color.Color,
) (fyne.CanvasObject, *container.Scroll) {
	// Header
	title := canvas.NewText("JOB QUEUE", titleColor)
	title.TextStyle = fyne.TextStyle{Monospace: true, Bold: true}
	title.TextSize = 24

	backBtn := widget.NewButton("← Back", onBack)
	backBtn.Importance = widget.LowImportance

	startAllBtn := widget.NewButton("Start Queue", onStart)
	startAllBtn.Importance = widget.MediumImportance

	pauseAllBtn := widget.NewButton("Pause All", onPauseAll)
	pauseAllBtn.Importance = widget.LowImportance

	resumeAllBtn := widget.NewButton("Resume All", onResumeAll)
	resumeAllBtn.Importance = widget.LowImportance

	clearBtn := widget.NewButton("Clear Completed", onClear)
	clearBtn.Importance = widget.LowImportance

	clearAllBtn := widget.NewButton("Clear All", onClearAll)
	clearAllBtn.Importance = widget.DangerImportance

	buttonRow := container.NewHBox(startAllBtn, pauseAllBtn, resumeAllBtn, clearAllBtn, clearBtn)

	header := container.NewBorder(
		nil, nil,
		backBtn,
		buttonRow,
		container.NewCenter(title),
	)

	// Job list
	var jobItems []fyne.CanvasObject

	if len(jobs) == 0 {
		emptyMsg := widget.NewLabel("No jobs in queue")
		emptyMsg.Alignment = fyne.TextAlignCenter
		jobItems = append(jobItems, container.NewCenter(emptyMsg))
	} else {
		for _, job := range jobs {
			jobItems = append(jobItems, buildJobItem(job, onPause, onResume, onCancel, onRemove, onMoveUp, onMoveDown, onCopyError, onViewLog, bgColor, textColor))
		}
	}

	jobList := container.NewVBox(jobItems...)
	// Use a scroll container anchored to the top to avoid jumpy scroll-to-content behavior.
	scrollable := container.NewScroll(jobList)
	scrollable.SetMinSize(fyne.NewSize(0, 0))
	scrollable.Offset = fyne.NewPos(0, 0)

	body := container.NewBorder(
		header,
		nil, nil, nil,
		scrollable,
	)

	return container.NewPadded(body), scrollable
}

// buildJobItem creates a single job item in the queue list
func buildJobItem(
	job *queue.Job,
	onPause func(string),
	onResume func(string),
	onCancel func(string),
	onRemove func(string),
	onMoveUp func(string),
	onMoveDown func(string),
	onCopyError func(string),
	onViewLog func(string),
	bgColor, textColor color.Color,
) fyne.CanvasObject {
	// Status color
	statusColor := getStatusColor(job.Status)

	// Status indicator
	statusRect := canvas.NewRectangle(statusColor)
	statusRect.SetMinSize(fyne.NewSize(6, 0))

	// Title and description
	titleText := utils.ShortenMiddle(job.Title, 60)
	descText := utils.ShortenMiddle(job.Description, 90)

	titleLabel := widget.NewLabel(titleText)
	titleLabel.TextStyle = fyne.TextStyle{Bold: true}

	descLabel := widget.NewLabel(descText)
	descLabel.TextStyle = fyne.TextStyle{Italic: true}
	descLabel.Wrapping = fyne.TextWrapWord

	// Progress bar (for running jobs)
	progress := newStripedProgress(moduleColor(job.Type))
	progress.SetProgress(job.Progress / 100.0)
	if job.Status == queue.JobStatusCompleted {
		progress.SetProgress(1.0)
	}
	progressWidget := progress

	// Module badge
	badge := buildModuleBadge(job.Type)

	// Status text
	statusText := getStatusText(job)
	statusLabel := widget.NewLabel(statusText)
	statusLabel.TextStyle = fyne.TextStyle{Monospace: true}
	statusLabel.Wrapping = fyne.TextWrapWord

	// Control buttons
	var buttons []fyne.CanvasObject
	// Reorder arrows for pending/paused jobs
	if job.Status == queue.JobStatusPending || job.Status == queue.JobStatusPaused {
		buttons = append(buttons,
			widget.NewButton("↑", func() { onMoveUp(job.ID) }),
			widget.NewButton("↓", func() { onMoveDown(job.ID) }),
		)
	}

	switch job.Status {
	case queue.JobStatusRunning:
		buttons = append(buttons,
			widget.NewButton("Pause", func() { onPause(job.ID) }),
			widget.NewButton("Cancel", func() { onCancel(job.ID) }),
		)
	case queue.JobStatusPaused:
		buttons = append(buttons,
			widget.NewButton("Resume", func() { onResume(job.ID) }),
			widget.NewButton("Cancel", func() { onCancel(job.ID) }),
		)
	case queue.JobStatusPending:
		buttons = append(buttons,
			widget.NewButton("Cancel", func() { onCancel(job.ID) }),
		)
	case queue.JobStatusCompleted, queue.JobStatusFailed, queue.JobStatusCancelled:
		if job.Status == queue.JobStatusFailed && strings.TrimSpace(job.Error) != "" && onCopyError != nil {
			buttons = append(buttons,
				widget.NewButton("Copy Error", func() { onCopyError(job.ID) }),
			)
		}
		if job.LogPath != "" && onViewLog != nil {
			buttons = append(buttons,
				widget.NewButton("View Log", func() { onViewLog(job.ID) }),
			)
		}
		buttons = append(buttons,
			widget.NewButton("Remove", func() { onRemove(job.ID) }),
		)
	}

	buttonBox := container.NewHBox(buttons...)

	// Info section
	infoBox := container.NewVBox(
		container.NewHBox(titleLabel, layout.NewSpacer(), badge),
		descLabel,
		progressWidget,
		statusLabel,
	)

	// Main content
	content := container.NewBorder(
		nil, nil,
		statusRect,
		buttonBox,
		infoBox,
	)

	// Card background
	card := canvas.NewRectangle(bgColor)
	card.CornerRadius = 4

	item := container.NewPadded(
		container.NewMax(card, content),
	)

	// Wrap with draggable to allow drag-to-reorder (up/down by drag direction)
	return newDraggableJobItem(job.ID, item, func(id string, dir int) {
		if dir < 0 {
			onMoveUp(id)
		} else if dir > 0 {
			onMoveDown(id)
		}
	})
}

// getStatusColor returns the color for a job status
func getStatusColor(status queue.JobStatus) color.Color {
	switch status {
	case queue.JobStatusPending:
		return color.RGBA{R: 150, G: 150, B: 150, A: 255} // Gray
	case queue.JobStatusRunning:
		return color.RGBA{R: 68, G: 136, B: 255, A: 255} // Blue
	case queue.JobStatusPaused:
		return color.RGBA{R: 255, G: 193, B: 7, A: 255} // Yellow
	case queue.JobStatusCompleted:
		return color.RGBA{R: 76, G: 232, B: 112, A: 255} // Green
	case queue.JobStatusFailed:
		return color.RGBA{R: 255, G: 68, B: 68, A: 255} // Red
	case queue.JobStatusCancelled:
		return color.RGBA{R: 255, G: 136, B: 68, A: 255} // Orange
	default:
		return color.Gray{Y: 128}
	}
}

// getStatusText returns a human-readable status string
func getStatusText(job *queue.Job) string {
	switch job.Status {
	case queue.JobStatusPending:
		return fmt.Sprintf("Status: Pending | Priority: %d", job.Priority)
	case queue.JobStatusRunning:
		elapsed := ""
		if job.StartedAt != nil {
			elapsed = fmt.Sprintf(" | Elapsed: %s", time.Since(*job.StartedAt).Round(time.Second))
		}

		// Add FPS and speed info if available in Config
		var extras string
		if job.Config != nil {
			if fps, ok := job.Config["fps"].(float64); ok && fps > 0 {
				extras += fmt.Sprintf(" | %.0f fps", fps)
			}
			if speed, ok := job.Config["speed"].(float64); ok && speed > 0 {
				extras += fmt.Sprintf(" | %.2fx", speed)
			}
			if etaDuration, ok := job.Config["eta"].(time.Duration); ok && etaDuration > 0 {
				extras += fmt.Sprintf(" | ETA %s", etaDuration.Round(time.Second))
			}
		}

		return fmt.Sprintf("Status: Running | Progress: %.1f%%%s%s", job.Progress, elapsed, extras)
	case queue.JobStatusPaused:
		return "Status: Paused"
	case queue.JobStatusCompleted:
		duration := ""
		if job.StartedAt != nil && job.CompletedAt != nil {
			duration = fmt.Sprintf(" | Duration: %s", job.CompletedAt.Sub(*job.StartedAt).Round(time.Second))
		}
		return fmt.Sprintf("Status: Completed%s", duration)
	case queue.JobStatusFailed:
		// Truncate error to prevent UI overflow
		errMsg := job.Error
		maxLen := 150
		if len(errMsg) > maxLen {
			errMsg = errMsg[:maxLen] + "… (see Copy Error button for full message)"
		}
		return fmt.Sprintf("Status: Failed | Error: %s", errMsg)
	case queue.JobStatusCancelled:
		return "Status: Cancelled"
	default:
		return fmt.Sprintf("Status: %s", job.Status)
	}
}

// buildModuleBadge renders a small colored pill to show which module created the job.
func buildModuleBadge(t queue.JobType) fyne.CanvasObject {
	label := widget.NewLabel(string(t))
	label.TextStyle = fyne.TextStyle{Bold: true}
	label.Alignment = fyne.TextAlignCenter

	bg := canvas.NewRectangle(moduleColor(t))
	bg.CornerRadius = 6
	bg.SetMinSize(fyne.NewSize(label.MinSize().Width+12, label.MinSize().Height+6))

	return container.NewMax(bg, container.NewCenter(label))
}

// moduleColor maps job types to distinct colors matching the main module colors
func moduleColor(t queue.JobType) color.Color {
	switch t {
	case queue.JobTypeConvert:
		return color.RGBA{R: 139, G: 68, B: 255, A: 255} // Violet (#8B44FF)
	case queue.JobTypeMerge:
		return color.RGBA{R: 68, G: 136, B: 255, A: 255} // Blue (#4488FF)
	case queue.JobTypeTrim:
		return color.RGBA{R: 68, G: 221, B: 255, A: 255} // Cyan (#44DDFF)
	case queue.JobTypeFilter:
		return color.RGBA{R: 68, G: 255, B: 136, A: 255} // Green (#44FF88)
	case queue.JobTypeUpscale:
		return color.RGBA{R: 170, G: 255, B: 68, A: 255} // Yellow-Green (#AAFF44)
	case queue.JobTypeAudio:
		return color.RGBA{R: 255, G: 215, B: 68, A: 255} // Yellow (#FFD744)
	case queue.JobTypeThumb:
		return color.RGBA{R: 255, G: 136, B: 68, A: 255} // Orange (#FF8844)
	default:
		return color.Gray{Y: 180}
	}
}

// draggableJobItem allows simple drag up/down to reorder one slot at a time.
type draggableJobItem struct {
	widget.BaseWidget
	jobID     string
	content   fyne.CanvasObject
	onReorder func(string, int) // id, direction (-1 up, +1 down)
	accumY    float32
}

func newDraggableJobItem(id string, content fyne.CanvasObject, onReorder func(string, int)) *draggableJobItem {
	d := &draggableJobItem{
		jobID:     id,
		content:   content,
		onReorder: onReorder,
	}
	d.ExtendBaseWidget(d)
	return d
}

func (d *draggableJobItem) CreateRenderer() fyne.WidgetRenderer {
	return widget.NewSimpleRenderer(d.content)
}

func (d *draggableJobItem) Dragged(ev *fyne.DragEvent) {
	// fyne.Delta is a struct with dx, dy fields
	d.accumY += ev.Dragged.DY
}

func (d *draggableJobItem) DragEnd() {
	const threshold float32 = 25
	if d.accumY <= -threshold {
		d.onReorder(d.jobID, -1)
	} else if d.accumY >= threshold {
		d.onReorder(d.jobID, 1)
	}
	d.accumY = 0
}