package tui

import (
	"fmt"
	"strings"

	"tui-ascii-mapper/internal/model"

	"github.com/charmbracelet/lipgloss"
)

const sidebarW = 18

var (
	toolbarStyle = lipgloss.NewStyle().Background(lipgloss.Color("235")).Foreground(lipgloss.Color("252"))
	sidebarStyle = lipgloss.NewStyle().Background(lipgloss.Color("235")).Foreground(lipgloss.Color("252"))
	statusStyle  = lipgloss.NewStyle().Background(lipgloss.Color("235")).Foreground(lipgloss.Color("252"))
	accentBg     = lipgloss.Color("33")
	accentFg     = lipgloss.Color("255")
)

func (m *AppModel) renderToolbar() string {
	items := []struct {
		label string
		width int
	}{
		{"Name", 16},
		{"Size", 10},
		{"File", 21},
		{"Uni", 5},
		{"Col", 5},
		{"Fil", 5},
		{"Save", 6},
		{"Load", 6},
		{"Quit", 6},
	}
	var styles []string
	for i, it := range items {
		var txt string
		on := false
		switch i {
		case 0:
			txt = " " + truncate(m.curMap().Name, it.width-2) + " "
		case 1:
			txt = fmt.Sprintf(" %dx%d ", m.curMap().Width, m.curMap().Height)
		case 2:
			txt = " " + truncate(shortFilename(m.rootMap.Filename), it.width-2) + " "
		case 3:
			txt = "[Uni]"
			on = m.unicode
		case 4:
			txt = "[Col]"
			on = m.colorMode
		case 5:
			txt = "[Fil]"
			on = m.fillShapes
		case 6:
			txt = "[Save]"
			if strings.Contains(m.dialogMsg, "Saved") {
				on = true
			}
		case 7:
			txt = "[Load]"
		case 8:
			txt = "[Quit]"
		}
		s := lipgloss.NewStyle().Width(it.width)
		if on {
			s = s.Background(lipgloss.Color("33")).Foreground(lipgloss.Color("0"))
		} else {
			s = s.Background(lipgloss.Color("235")).Foreground(lipgloss.Color("252"))
		}
		styles = append(styles, s.Render(txt))
	}
	return toolbarStyle.Width(m.width).Render(lipgloss.JoinHorizontal(lipgloss.Top, styles...))
}

func truncate(s string, w int) string {
	r := []rune(s)
	if len(r) <= w {
		return s
	}
	return string(r[:max(0, w-1)]) + "\u2026"
}

func (m *AppModel) renderGrid(gw, gh int) string {
	var sb strings.Builder
	for row := 0; row < gh; row++ {
		my := row + m.offset.Y
		for col := 0; col < gw; col++ {
			mx := col + m.offset.X
			p := model.Point{X: mx, Y: my}
			if !m.curMap().InBounds(p) {
				sb.WriteString(m.cellStr("\u00b7", "240", "", false, false, false))
				continue
			}
			cell := m.curMap().CellAt(p)
			isCursor := !m.mouseDown && p == m.cursor
			isPreview := m.isPreviewCell(p)
			hasSub := false
			if _, ok := m.curMap().Submaps[p]; ok {
				hasSub = true
			}

			var sym string
			var fg string
			var bg string

			showText := cell.Text != ""
			if showText && m.movingLabel >= 0 && m.movingLabel < len(m.curMap().TextLabels) {
				tl := m.curMap().TextLabels[m.movingLabel]
				runes := []rune(tl.Text)
				for i := range runes {
					if tl.Start.X+i == p.X && tl.Start.Y == p.Y {
						showText = false
						break
					}
				}
			}
			if showText {
				sym = cell.Text
				fg = "15"
			} else if cell.Terrain >= 0 && cell.Terrain < len(m.curPalette()) {
				sym = m.curPalette()[cell.Terrain].GetSymbol(m.unicode)
			} else {
				sym = " "
			}

			if cell.Text == "" && m.colorMode {
				if cell.Terrain >= 0 && cell.Color != "" {
					fg = cell.Color
				} else if cell.Terrain >= 0 {
					fg = "255"
				}
			}
			if hasSub {
				bg = m.cfg.SubmapBg
			}
			if isPreview && sym == " " {
				sym = "\u00b7"
				fg = "250"
			}

			if m.mode == model.ModeTextEdit && m.tool == model.ToolText {
				text := m.textInput.Value()
				cursorCh := ""
				if m.textInput.Focused() {
					cursorCh = "\u2502"
				}
				runes := []rune(text + cursorCh)
				for i, r := range runes {
					if p.X == m.textCursorStart.X+i && p.Y == m.textCursorStart.Y {
						sym = string(r)
						fg = "15"
						break
					}
				}
			}
			if m.mode != model.ModeTextEdit && m.movingLabel >= 0 && m.movingLabel < len(m.curMap().TextLabels) {
				tl := m.curMap().TextLabels[m.movingLabel]
				pos := m.labelDragPos()
				runes := []rune(tl.Text)
				for i, r := range runes {
					if p.X == pos.X+i && p.Y == pos.Y {
						sym = string(r)
						fg = "15"
						break
					}
				}
			}

			sb.WriteString(m.cellStr(sym, fg, bg, isCursor, isPreview, false))
		}
		if row < gh-1 {
			sb.WriteByte('\n')
		}
	}
	return sb.String()
}

func (m *AppModel) isPreviewCell(p model.Point) bool {
	for _, pt := range m.linePreview {
		if pt == p {
			return true
		}
	}
	for _, pt := range m.rectPreview {
		if pt == p {
			return true
		}
	}
	for _, pt := range m.circlePreview {
		if pt == p {
			return true
		}
	}
	return false
}

func (m *AppModel) cellStr(sym, fg, bg string, cursor, preview, reverse bool) string {
	if cursor {
		return styledCell(sym, "0", "15", true)
	}
	if preview {
		return styledCell(sym, fg, "240", false)
	}
	if bg != "" || fg != "" {
		return styledCell(sym, fg, bg, false)
	}
	return sym
}

func styledCell(sym, fg, bg string, reverse bool) string {
	var parts []string
	if reverse {
		parts = append(parts, "\033[7m")
	} else {
		if bg != "" {
			parts = append(parts, "\033[48;5;"+bg+"m")
		}
		if fg != "" {
			parts = append(parts, "\033[38;5;"+fg+"m")
		}
	}
	if len(parts) > 0 {
		parts = append(parts, sym, "\033[0m")
		return strings.Join(parts, "")
	}
	return sym
}

func (m *AppModel) renderSidebar(gh int) string {
	palette := m.curPalette()
	totalPages := (len(palette) + 9) / 10
	startIdx := m.palettePage * 10
	endIdx := startIdx + 10
	if endIdx > len(palette) {
		endIdx = len(palette)
	}

	var sb strings.Builder
	sb.WriteString(sidebarStyle.Width(sidebarW).Render("   ══ Symbols ══"))
	sb.WriteByte('\n')
	for i := startIdx; i < endIdx; i++ {
		t := palette[i]
		idx := i % 10
		sym := t.GetSymbol(m.unicode)
		fg := "252"
		if m.colorMode && len(t.Colors) > 0 {
			fg = t.Colors[0].Color
		}
		coloredSym := lipgloss.NewStyle().Foreground(lipgloss.Color(fg)).Render(sym)
		label := fmt.Sprintf("%d %s %-9s", (idx+1)%10, coloredSym, t.Name)
		if i == m.selected {
			label = lipgloss.NewStyle().
				Background(accentBg).Foreground(accentFg).
				Width(sidebarW).Render(label)
		} else {
			label = lipgloss.NewStyle().
				Foreground(lipgloss.Color("252")).
				Width(sidebarW).Render(label)
		}
		sb.WriteString(label)
		sb.WriteByte('\n')
	}
	for i := endIdx - startIdx; i < 10; i++ {
		sb.WriteByte('\n')
	}
	pageLabel := fmt.Sprintf(" << page %d/%d >> ", m.palettePage+1, totalPages)
	sb.WriteString(sidebarStyle.Width(sidebarW).Render(pageLabel))
	sb.WriteByte('\n')
	sb.WriteString(lipgloss.NewStyle().Width(sidebarW).Render(" [+ Add] [- Del]"))
	sb.WriteByte('\n')
	sb.WriteString(lipgloss.NewStyle().Width(sidebarW).Render(" [▲ Up] [▼ Down]"))
	sb.WriteByte('\n')
	sb.WriteString(lipgloss.NewStyle().Width(sidebarW).Render(" [Rename] [Color]"))
	sb.WriteByte('\n')
	sb.WriteString(sidebarStyle.Width(sidebarW).Render("   ══ Tools ══"))
	sb.WriteByte('\n')
	tools_ := []model.Tool{model.ToolBrush, model.ToolSelect, model.ToolErase, model.ToolFill, model.ToolLine, model.ToolRect, model.ToolCircle, model.ToolText}
	tlabels := []string{"1 Brush", "2 Select", "3 Erase", "4 Fill", "5 Line", "6 Rect", "7 Circle", "8 Text"}
	for i, tn := range tlabels {
		label := tn
		if tools_[i] == m.tool {
			label = lipgloss.NewStyle().Background(accentBg).Foreground(accentFg).Width(sidebarW).Render(tn)
		}
		if label == tn {
			label = lipgloss.NewStyle().Width(sidebarW).Render(label)
		}
		sb.WriteString(label)
		sb.WriteByte('\n')
	}
	sb.WriteString(sidebarStyle.Width(sidebarW).Render("══ Brush Width ══"))
	sb.WriteByte('\n')
	for _, bw := range []int{1, 3, 5} {
		label := fmt.Sprintf("  %dx%d", bw, bw)
		if bw == m.brushWidth {
			label = lipgloss.NewStyle().Background(accentBg).Foreground(accentFg).Width(sidebarW).Render(label)
		} else {
			label = lipgloss.NewStyle().Width(sidebarW).Render(label)
		}
		sb.WriteString(label)
		sb.WriteByte('\n')
	}
	lines := strings.Split(sb.String(), "\n")
	if len(lines) > gh {
		lines = lines[:gh]
	}
	return strings.Join(lines, "\n")
}

func (m *AppModel) renderStatus() string {
	cell := m.curMap().CellAt(m.cursor)
	terrainName := ""
	if cell.Terrain >= 0 && cell.Terrain < len(m.curPalette()) {
		terrainName = m.curPalette()[cell.Terrain].Name
	}
	subInfo := ""
	if _, ok := m.curMap().Submaps[m.cursor]; ok {
		subInfo = " [submap]"
	}
	modeLabel := m.tool.String()
	if m.drawHeld {
		modeLabel += " [DRAW]"
	} else if m.eraseHeld {
		modeLabel += " [ERASE]"
	}
	feedback := ""
	if m.dialogMsg != "" {
		feedback = " " + m.dialogMsg
	}
	return statusStyle.Width(m.width).Render(
		fmt.Sprintf(" %d,%d %s %s %s%s%s",
			m.cursor.X, m.cursor.Y,
			modeLabel, terrainName, m.curMap().Name, subInfo, feedback))
}

func (m *AppModel) renderHelp() string {
	cfg := m.cfg.Keybindings
	help := fmt.Sprintf(" %s:Save %s:Quit %s:Undo %s:Redo Space:Draw Bksp:Erase Enter:Sub Esc:Up Arrows:Move 1-8:Tools f:FillShp []:Width",
		cfg.Save, cfg.Quit, cfg.Undo, cfg.Redo)
	if len(help) > m.width && m.width > 3 {
		help = help[:m.width-3] + "..."
	}
	return statusStyle.Width(m.width).Render(help)
}

func (m *AppModel) renderDialogBox() string {
	switch m.dialog {
	case model.DialogSaveAs:
		return m.renderFilePickerPopup("Save As")
	case model.DialogOpenMap:
		return m.renderFilePickerPopup("Open Map")
	case model.DialogFileSave:
		return m.renderFilePickerPopup("Save As")
	case model.DialogFileOpen:
		return m.renderFilePickerPopup("Open Map")
	case model.DialogResize:
		return renderPopup("Resize Map", "Size (e.g. 80x25):", m.ti.View())
	case model.DialogQuitConfirm:
		return renderPopup("Quit", "Quit without saving?", "[Enter] Quit  [Esc] Cancel")
	case model.DialogDeleteSubmapConfirm:
		return renderPopup("Delete Submap",
			fmt.Sprintf("Delete submap at %d,%d?", m.cursor.X, m.cursor.Y),
			"[Enter] Confirm  [Esc] Cancel")
	case model.DialogRenameSymbol:
		return renderPopup("Rename Symbol", "New name:", m.ti.View())
	case model.DialogRenameMap:
		return renderPopup("Rename Map", "New name:", m.ti.View())
	}
	return ""
}

func (m *AppModel) renderDialogFullscreen() string {
	popup := m.renderDialogBox()
	return m.centeredFullscreen(popup)
}

func (m *AppModel) renderFilePickerPopup(title string) string {
	if m.filePicker == nil {
		return renderPopup(title, "", "Loading...")
	}

	var sb strings.Builder
	sb.WriteString(lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("33")).Render(title))
	sb.WriteString("\n\n")
	sb.WriteString("Path: ")
	sb.WriteString(m.filePicker.CurDir)
	sb.WriteString("\n")
	sb.WriteString("File: ")
	sb.WriteString(m.ti.View())
	sb.WriteString("\n\n")

	dirStyle := lipgloss.NewStyle().Foreground(lipgloss.Color("39"))
	fileStyle := lipgloss.NewStyle().Foreground(lipgloss.Color("252"))
	selStyle := lipgloss.NewStyle().Background(lipgloss.Color("33")).Foreground(lipgloss.Color("0"))
	sizeStyle := lipgloss.NewStyle().Foreground(lipgloss.Color("243"))

	maxShow := 15
	start := m.filePicker.Selected - maxShow/2
	if start < 0 {
		start = 0
	}
	end := start + maxShow
	if end > len(m.filePicker.Files) {
		end = len(m.filePicker.Files)
		start = end - maxShow
		if start < 0 {
			start = 0
		}
	}

	for i := start; i < end; i++ {
		entry := m.filePicker.Files[i]
		name := entry.Name()
		var line string

		if entry.IsDir() {
			line = dirStyle.Render(name + "/")
		} else {
			info, err := entry.Info()
			if err == nil {
				line = fmt.Sprintf("%s  %s", sizeStyle.Render(formatSize(info.Size())), fileStyle.Render(name))
			} else {
				line = fmt.Sprintf("%s  %s", sizeStyle.Render(" ???"), fileStyle.Render(name))
			}
		}

		if i == m.filePicker.Selected {
			line = selStyle.Render(fmt.Sprintf(" >%s", line))
		} else {
			line = fmt.Sprintf("  %s", line)
		}
		sb.WriteString(line)
		sb.WriteByte('\n')
	}

	if len(m.filePicker.Files) == 0 {
		sb.WriteString("  (empty directory)\n")
	}

	sb.WriteString("\n[Enter] Select  [Esc] Cancel  [Left] Up")

	w := 55
	popup := lipgloss.NewStyle().
		Border(lipgloss.RoundedBorder()).
		Background(lipgloss.Color("234")).
		Padding(1, 2).
		Width(w).
		Render(sb.String())

	popupW := lipgloss.Width(popup)
	popupH := lipgloss.Height(popup)
	m.filePicker.PopupX = (m.width-popupW)/2 + 1 + 2
	m.filePicker.PopupY = (m.height-popupH)/2 + 7
	m.filePicker.ListTop = start
	if m.filePicker.PopupX < 0 {
		m.filePicker.PopupX = 0
	}
	if m.filePicker.PopupY < 0 {
		m.filePicker.PopupY = 0
	}

	return popup
}