package tui

import (
	"fmt"
	"os"
	"path/filepath"
	"sort"
	"strings"

	"tui-ascii-mapper/internal/mapio"
	"tui-ascii-mapper/internal/model"

	tea "github.com/charmbracelet/bubbletea"
)

func (m *AppModel) handleDialogKey(msg tea.KeyMsg) (tea.Model, tea.Cmd) {
	key := msg.String()

	isFilePicker := m.dialog == model.DialogFileSave || m.dialog == model.DialogFileOpen || m.dialog == model.DialogSaveAs || m.dialog == model.DialogOpenMap
	if isFilePicker && m.filePicker != nil {
		switch key {
		case "esc":
			m.mode = model.ModeNormal
			m.dialog = model.DialogNone
			m.filePicker = nil
			return m, nil
		case "up":
			if m.filePicker.Selected > 0 {
				m.filePicker.Selected--
			}
			return m, nil
		case "down":
			if m.filePicker.Selected < len(m.filePicker.Files)-1 {
				m.filePicker.Selected++
			}
			return m, nil
		case "pgup":
			m.filePicker.Selected -= 10
			if m.filePicker.Selected < 0 {
				m.filePicker.Selected = 0
			}
			return m, nil
		case "pgdown":
			m.filePicker.Selected += 10
			if m.filePicker.Selected >= len(m.filePicker.Files) {
				m.filePicker.Selected = len(m.filePicker.Files) - 1
			}
			return m, nil
		case "left":
			parent := filepath.Dir(m.filePicker.CurDir)
			m.filePicker.CurDir = parent
			m.filePicker.Selected = 0
			m.refreshFilePicker()
			return m, nil
		case "enter":
			tiVal := strings.TrimSpace(m.ti.Value())
			if tiVal != "" {
				m.filePicker = nil
				return m.doFileAction(tiVal)
			}
			if m.filePicker.Selected >= 0 && m.filePicker.Selected < len(m.filePicker.Files) {
				entry := m.filePicker.Files[m.filePicker.Selected]
				if entry.IsDir() {
					m.filePicker.CurDir = filepath.Join(m.filePicker.CurDir, entry.Name())
					m.filePicker.Selected = 0
					m.refreshFilePicker()
					return m, nil
				}
				fullPath := filepath.Join(m.filePicker.CurDir, entry.Name())
				m.ti.SetValue(fullPath)
				m.filePicker = nil
				return m.doFileAction(fullPath)
			}
			return m, nil
		}
		var cmd tea.Cmd
		m.ti, cmd = m.ti.Update(msg)
		return m, cmd
	}

	switch key {
	case "esc":
		if m.dialog == model.DialogQuitConfirm {
			m.quitting = true
			return m, tea.Quit
		}
		m.mode = model.ModeNormal
		m.dialog = model.DialogNone
		return m, nil
	case "q":
		if m.dialog == model.DialogQuitConfirm {
			m.quitting = true
			return m, tea.Quit
		}
		fallthrough
	default:
		var cmd tea.Cmd
		m.ti, cmd = m.ti.Update(msg)
		return m, cmd
	case "enter":
		switch m.dialog {
		case model.DialogSaveAs:
			name := m.ti.Value()
			if name != "" {
				m.rootMap.Filename = name
				if err := mapio.SerializeMap(m.rootMap, name); err != nil {
					m.dialogMsg = err.Error()
				} else {
					m.dialogMsg = fmt.Sprintf("Saved %s", name)
					m.dirty = false
					m.undoPosAtSave = m.undo.Pos()
				}
			}
		case model.DialogResize:
			var w, h int
			val := m.ti.Value()
			if n, _ := fmt.Sscanf(val, "%dx%d", &w, &h); n == 2 && w > 0 && h > 0 && w < 1000 && h < 1000 {
				m.resizeMap(w, h)
			}
		case model.DialogQuitConfirm:
			m.quitting = true
			return m, tea.Quit
		case model.DialogDeleteSubmapConfirm:
			m.dirty = true
			m.undo.Push(m.curMap())
			delete(m.curMap().Submaps, m.cursor)
		case model.DialogRenameSymbol:
			name := m.ti.Value()
			if name != "" && m.selected < len(m.curPalette()) {
				m.curPalette()[m.selected].Name = name
			}
		case model.DialogRenameMap:
			name := m.ti.Value()
			if name != "" {
				m.curMap().Name = name
			}
		case model.DialogOpenMap:
			name := m.ti.Value()
			if name != "" {
				return m, m.loadMapCmd(name)
			}
		}
		m.mode = model.ModeNormal
		m.dialog = model.DialogNone
		return m, nil
	}
}

func (m *AppModel) doFileAction(path string) (tea.Model, tea.Cmd) {
	switch m.dialog {
	case model.DialogFileSave, model.DialogSaveAs:
		m.rootMap.Filename = path
		if err := mapio.SerializeMap(m.rootMap, path); err != nil {
			m.dialogMsg = err.Error()
		} else {
			m.dialogMsg = fmt.Sprintf("Saved %s", path)
			m.dirty = false
			m.undoPosAtSave = m.undo.Pos()
		}
	case model.DialogFileOpen, model.DialogOpenMap:
		m.mode = model.ModeNormal
		m.dialog = model.DialogNone
		return m, m.loadMapCmd(path)
	}
	m.mode = model.ModeNormal
	m.dialog = model.DialogNone
	return m, nil
}

func (m *AppModel) handleFilePickerMouse(msg tea.MouseMsg) (tea.Model, tea.Cmd) {
	_, y := msg.X, msg.Y
	if msg.Button != tea.MouseButtonLeft || msg.Action != tea.MouseActionPress {
		return m, nil
	}
	entryY := y - m.filePicker.PopupY
	if entryY >= 0 && entryY < len(m.filePicker.Files) {
		idx := entryY + m.filePicker.ListTop
		if idx >= 0 && idx < len(m.filePicker.Files) {
			m.filePicker.Selected = idx
			entry := m.filePicker.Files[idx]
			if entry.IsDir() {
				m.filePicker.CurDir = filepath.Join(m.filePicker.CurDir, entry.Name())
				m.filePicker.Selected = 0
				m.refreshFilePicker()
			} else {
				fullPath := filepath.Join(m.filePicker.CurDir, entry.Name())
				m.ti.SetValue(fullPath)
				m.filePicker = nil
				return m.doFileAction(fullPath)
			}
		}
	}
	return m, nil
}

func (m *AppModel) saveMap() {
	if m.rootMap.Filename == "" {
		m.mode = model.ModeDialog
		m.dialog = model.DialogFileSave
		m.openFilePicker()
		m.ti.Focus()
		return
	}
	if err := mapio.SerializeMap(m.rootMap, m.rootMap.Filename); err != nil {
		m.dialogMsg = fmt.Sprintf("Save error: %v", err)
	} else {
		m.dialogMsg = fmt.Sprintf("Saved %s", m.rootMap.Filename)
		m.dirty = false
		m.undoPosAtSave = m.undo.Pos()
	}
}

func (m *AppModel) openFilePicker() {
	cur := "."
	m.filePicker = &FilePickerState{CurDir: cur, Selected: 0}
	m.refreshFilePicker()
	m.ti.SetValue("")
}

func (m *AppModel) refreshFilePicker() {
	entries, err := os.ReadDir(m.filePicker.CurDir)
	if err != nil {
		m.filePicker.Files = nil
		return
	}
	sort.Slice(entries, func(i, j int) bool {
		if entries[i].IsDir() != entries[j].IsDir() {
			return entries[i].IsDir()
		}
		return entries[i].Name() < entries[j].Name()
	})
	m.filePicker.Files = entries
	if m.filePicker.Selected >= len(entries) {
		m.filePicker.Selected = len(entries) - 1
	}
	if m.filePicker.Selected < 0 {
		m.filePicker.Selected = 0
	}
}

func (m *AppModel) doFilePickerSelect() {
	if m.filePicker == nil || len(m.filePicker.Files) == 0 {
		return
	}
	entry := m.filePicker.Files[m.filePicker.Selected]
	if entry.IsDir() {
		m.filePicker.CurDir = filepath.Join(m.filePicker.CurDir, entry.Name())
		m.filePicker.Selected = 0
		m.refreshFilePicker()
		return
	}
	m.ti.SetValue(filepath.Join(m.filePicker.CurDir, entry.Name()))
}

func (m *AppModel) drillDown() {
	m.cancelPreview()
	sub, ok := m.curMap().Submaps[m.cursor]
	if !ok {
		sub = model.NewMap(fmt.Sprintf("%s/sub", m.curMap().Name),
			m.cfg.DefaultMapWidth, m.cfg.DefaultMapHeight,
			m.curMap().Palette)
		sub.Parent = m.curMap()
		sub.Filename = m.rootMap.Filename
		m.curMap().Submaps[m.cursor] = sub
	}
	m.prevCursor = m.cursor
	m.map_ = sub
	m.cursor = model.Point{X: 0, Y: 0}
	m.offset = model.Point{X: 0, Y: 0}
}

func (m *AppModel) drillUp() {
	if m.curMap().Parent == nil {
		return
	}
	if m.isMapBlank(m.curMap()) {
		delete(m.curMap().Parent.Submaps, m.prevCursor)
	}
	parent := m.curMap().Parent
	m.map_ = parent
	if m.prevCursor.X >= 0 {
		m.cursor = m.prevCursor
	} else {
		m.cursor = model.Point{X: -1, Y: -1}
	}
	m.offset = model.Point{X: 0, Y: 0}
	m.prevCursor = model.Point{X: -1, Y: -1}
}

func (m *AppModel) isMapBlank(mm *model.Map) bool {
	for y := range mm.Grid {
		for x := range mm.Grid[y] {
			if mm.Grid[y][x].Terrain >= 0 || mm.Grid[y][x].Text != "" {
				return false
			}
		}
	}
	return len(mm.Submaps) == 0
}

func (m *AppModel) handleToolbarClick(x int) {
	widths := []int{16, 10, 21, 5, 5, 5, 6, 6, 6}
	pos := 0
	for i, w := range widths {
		if x >= pos && x < pos+w {
			switch i {
			case 0:
				m.mode = model.ModeDialog
				m.dialog = model.DialogRenameMap
				m.ti.SetValue(m.curMap().Name)
				m.ti.Focus()
			case 1:
				m.mode = model.ModeDialog
				m.dialog = model.DialogResize
				m.ti.SetValue(fmt.Sprintf("%dx%d", m.curMap().Width, m.curMap().Height))
				m.ti.Focus()
			case 2:
				m.mode = model.ModeDialog
				m.dialog = model.DialogFileSave
				m.openFilePicker()
				m.ti.SetValue(m.rootMap.Filename)
				m.ti.Focus()
			case 3:
				m.unicode = !m.unicode
			case 4:
				m.colorMode = !m.colorMode
			case 5:
				m.fillShapes = !m.fillShapes
			case 6:
				m.saveMap()
			case 7:
				m.mode = model.ModeDialog
				m.dialog = model.DialogFileOpen
				m.openFilePicker()
				m.ti.Focus()
			case 8:
				if m.dirty {
					m.mode = model.ModeDialog
					m.dialog = model.DialogQuitConfirm
				} else {
					m.quitting = true
				}
			}
			return
		}
		pos += w
	}
}

func (m *AppModel) handleSidebarClick(x, y int) {
	relY := y - 1

	if relY >= 1 && relY <= 10 {
		idx := m.palettePage*10 + (relY - 1)
		if idx < len(m.curPalette()) {
			m.selected = idx
		}
		return
	}

	if relY == 11 {
		if x < m.width-sidebarW+7 {
			m.palettePagePrev()
		} else {
			m.palettePageNext()
		}
		return
	}

	if relY == 12 {
		if x < m.width-sidebarW+8 {
			m.addSymbol()
		} else {
			m.removeSymbol()
		}
		return
	}
	if relY == 13 {
		if x < m.width-sidebarW+8 {
			m.moveSymbolUp()
		} else {
			m.moveSymbolDown()
		}
		return
	}
	if relY == 14 {
		if x < m.width-sidebarW+10 {
			m.mode = model.ModeDialog
			m.dialog = model.DialogRenameSymbol
			m.ti.SetValue(m.curPalette()[model.Clamp(m.selected, 0, len(m.curPalette())-1)].Name)
			m.ti.Focus()
		} else {
			m.openColorPicker(false)
		}
		return
	}

	toolRow := relY - 16
	if toolRow >= 0 && toolRow < 8 {
		newTool := model.Tool(toolRow)
		if m.tool != newTool && m.mode == model.ModeTextEdit {
			m.mode = model.ModeNormal
			m.movingLabel = -1
			m.textEditing = false
			m.textInput.Blur()
		}
		m.tool = newTool
	}
	bwRow := relY - 25
	if bwRow >= 0 && bwRow < 3 {
		m.brushWidth = []int{1, 3, 5}[bwRow]
	}
}

func (m *AppModel) addSymbol() {
	p := m.curPalette()
	if len(p) >= 100 {
		return
	}
	m.dirty = true
	m.undo.Push(m.curMap())
	m.curMap().Palette = append(p, model.Terrain{Name: "new", Symbol: "?", ASCII: "?", Colors: []model.TerrainColor{{Color: "255", Weight: 100}}})
}

func (m *AppModel) removeSymbol() {
	if len(m.curPalette()) <= 1 {
		return
	}
	m.dirty = true
	m.undo.Push(m.curMap())
	idx := model.Clamp(m.selected, 0, len(m.curPalette())-1)
	for y := range m.curMap().Grid {
		for x := range m.curMap().Grid[y] {
			c := &m.curMap().Grid[y][x]
			if c.Terrain == idx {
				c.Terrain = -1
			} else if c.Terrain > idx {
				c.Terrain--
			}
		}
	}
	m.curMap().Palette = append(m.curMap().Palette[:idx], m.curMap().Palette[idx+1:]...)
	if m.selected >= len(m.curPalette()) {
		m.selected = len(m.curPalette()) - 1
	}
}

func (m *AppModel) moveSymbolUp() {
	if m.selected <= 0 || m.selected >= len(m.curPalette()) {
		return
	}
	m.dirty = true
	m.undo.Push(m.curMap())
	i := m.selected
	m.curPalette()[i], m.curPalette()[i-1] = m.curPalette()[i-1], m.curPalette()[i]
	for y := range m.curMap().Grid {
		for x := range m.curMap().Grid[y] {
			c := &m.curMap().Grid[y][x]
			if c.Terrain == i {
				c.Terrain = i - 1
			} else if c.Terrain == i-1 {
				c.Terrain = i
			}
		}
	}
	m.selected = i - 1
}

func (m *AppModel) moveSymbolDown() {
	if m.selected < 0 || m.selected >= len(m.curPalette())-1 {
		return
	}
	m.dirty = true
	m.undo.Push(m.curMap())
	i := m.selected
	m.curPalette()[i], m.curPalette()[i+1] = m.curPalette()[i+1], m.curPalette()[i]
	for y := range m.curMap().Grid {
		for x := range m.curMap().Grid[y] {
			c := &m.curMap().Grid[y][x]
			if c.Terrain == i {
				c.Terrain = i + 1
			} else if c.Terrain == i+1 {
				c.Terrain = i
			}
		}
	}
	m.selected = i + 1
}

func (m *AppModel) palettePagePrev() {
	totalPages := (len(m.curPalette()) + 9) / 10
	if totalPages <= 1 {
		return
	}
	m.palettePage = (m.palettePage - 1 + totalPages) % totalPages
}

func (m *AppModel) palettePageNext() {
	totalPages := (len(m.curPalette()) + 9) / 10
	if totalPages <= 1 {
		return
	}
	m.palettePage = (m.palettePage + 1) % totalPages
}

func (m *AppModel) resizeMap(w, h int) {
	m.dirty = true
	m.undo.Push(m.curMap())
	old := m.curMap()
	newGrid := make([][]model.Cell, h)
	for y := range newGrid {
		newGrid[y] = make([]model.Cell, w)
		for x := range newGrid[y] {
			if y < old.Height && x < old.Width {
				newGrid[y][x] = old.Grid[y][x]
			} else {
				newGrid[y][x].Terrain = -1
			}
		}
	}
	old.Grid = newGrid
	old.Width = w
	old.Height = h
	m.cursor.X = model.Clamp(m.cursor.X, 0, w-1)
	m.cursor.Y = model.Clamp(m.cursor.Y, 0, h-1)
}