package game

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

	"github.com/hajimehoshi/ebiten/v2"
	"github.com/hajimehoshi/ebiten/v2/vector"

	"gitea.brasse-pc.eu/brasse/metro-puzzle-jp/internal/buildinfo"
	"gitea.brasse-pc.eu/brasse/metro-puzzle-jp/internal/level"
)

// MapScene är bankartan i spelbrädesstil: huvudbanorna på en slingrande
// linje från flygplatsen, sidobanorna som avstickare ovanför. Låsta banor
// är grå, klarade visar stjärnor.
type MapScene struct {
	confirmNG bool // G tryckt en gång: nästa G startar New Game+
	mains     []*level.Level
	sides     map[string][]*level.Level // parent -> sidobanor
	sel       int                       // vald huvudbana
	side      int                       // 0 = huvudbanan, 1.. = sidobana nr
	msg       string
}

type mapNode struct {
	lvl  *level.Level
	x, y int
}

// NewMapScene bygger kartan från alla banor.
func NewMapScene(g *Game) *MapScene {
	m := &MapScene{sides: map[string][]*level.Level{}}
	for _, l := range g.Levels {
		switch {
		case l.IsLeg(): // delbanor nås via sin resa
		case l.IsSide():
			m.sides[l.Parent] = append(m.sides[l.Parent], l)
		default:
			m.mains = append(m.mains, l)
		}
	}
	sort.Slice(m.mains, func(i, j int) bool { return m.mains[i].Order < m.mains[j].Order })
	// Välj den första banan som inte är klarad.
	for i, l := range m.mains {
		if !g.Progress.Cleared(l.ID) {
			m.sel = i
			break
		}
	}
	return m
}

// nodes ger positionerna på kartan.
func (m *MapScene) nodes() ([]mapNode, map[string][]mapNode) {
	n := len(m.mains)
	var mains []mapNode
	sides := map[string][]mapNode{}
	for i, l := range m.mains {
		x := 36
		if n > 1 {
			x = 36 + i*(ScreenW-72)/(n-1)
		}
		y := 104
		if i%2 == 1 {
			y = 116
		}
		mains = append(mains, mapNode{l, x, y})
		for k, s := range m.sides[l.ID] {
			sides[l.ID] = append(sides[l.ID], mapNode{s, x + 12 + k*18, y - 40})
		}
	}
	return mains, sides
}

func (m *MapScene) current() *level.Level {
	if len(m.mains) == 0 {
		return nil
	}
	main := m.mains[m.sel]
	if m.side > 0 {
		if s := m.sides[main.ID]; m.side-1 < len(s) {
			return s[m.side-1]
		}
	}
	return main
}

func (m *MapScene) Update(g *Game) error {
	switch {
	case backJustPressed():
		return ebiten.Termination
	case wordsJustPressed():
		g.SetScene(NewWordsScene(g.Assets, m))
		return nil
	case skillsJustPressed():
		g.SetScene(NewSkillsScene(g, m))
		return nil
	case itemsJustPressed():
		g.SetScene(NewItemsScene(g, m))
		return nil
	case phoneJustPressed():
		g.Wallet.Phone = !g.Wallet.Phone
		g.Save()
	case modeJustPressed():
		g.toggleMode()
	case settingsJustPressed():
		g.SetScene(NewSettingsScene(m))
		return nil
	case endlessJustPressed() && g.Progress.StoryCleared:
		s, err := g.startEndless(g.seed())
		if err != nil {
			m.msg = err.Error()
			return nil
		}
		g.SetScene(s)
		return nil
	case ngPlusJustPressed() && g.Progress.StoryCleared:
		if !m.confirmNG {
			m.confirmNG = true
			m.msg = g.Assets.T("map.ngplus_confirm")
			return nil
		}
		g.newGamePlus()
		g.SetScene(NewMapScene(g))
		return nil
	}
	if m.confirmNG && (confirmJustPressed() || miniMoveXYAny()) {
		m.confirmNG, m.msg = false, "" // något annat tryckt: ingen NG+
	}
	if n := len(m.mains); n > 0 {
		mx, my := miniMoveXY()
		if mx != 0 {
			m.sel = (m.sel + mx + n) % n
			m.side = 0
		}
		if my != 0 {
			sides := len(m.sides[m.mains[m.sel].ID])
			m.side = max(0, min(sides, m.side-my)) // upp = ut på sidospåret
		}
		if confirmJustPressed() {
			l := m.current()
			if !g.Progress.Unlocked(g.Levels, l.ID) {
				m.msg = g.Assets.T("map.locked")
				return nil
			}
			s, err := g.startLevel(l.ID)
			if err != nil {
				m.msg = err.Error()
				return nil
			}
			g.SetScene(s)
		}
	}
	return nil
}

func (m *MapScene) Draw(g *Game, screen *ebiten.Image) {
	a := g.Assets
	p := g.Progress
	screen.Fill(color.RGBA{24, 20, 37, 255})
	vector.DrawFilledRect(screen, 0, 0, ScreenW, 22, color.RGBA{38, 43, 68, 255}, false)
	a.DrawBig(screen, a.T("game.title"), 8, 5, colText)
	hdr := fmt.Sprintf("%s %d  %s %d/%d  ★ %d", a.T("map.level"), p.Level(), a.T("map.xp"), p.XP, p.XP+progress_XPToNext(p.XP), p.TotalStars())
	a.Draw(screen, hdr, ScreenW-8-a.Width(hdr), 6, colKnown)

	mains, sides := m.nodes()
	// Linjen mellan huvudbanorna.
	for i := 1; i < len(mains); i++ {
		drawLine(screen, mains[i-1].x, mains[i-1].y, mains[i].x, mains[i].y, colBar)
	}
	for _, mn := range mains {
		for _, sn := range sides[mn.lvl.ID] {
			drawLine(screen, mn.x, mn.y, sn.x, sn.y, colBar)
		}
	}
	cur := m.current()
	drawNode := func(n mapNode, side bool) {
		sz := float32(14)
		if side {
			sz = 10
		}
		col := colDim
		unlocked := p.Unlocked(g.Levels, n.lvl.ID)
		switch {
		case p.Cleared(n.lvl.ID):
			col = colGood
		case unlocked:
			col = colText
		}
		vector.DrawFilledRect(screen, float32(n.x)-sz/2, float32(n.y)-sz/2, sz, sz, col, false)
		if n.lvl == cur {
			vector.DrawFilledRect(screen, float32(n.x)-sz/2-2, float32(n.y)-sz/2-2, sz+4, 2, colKnown, false)
			vector.DrawFilledRect(screen, float32(n.x)-sz/2-2, float32(n.y)+sz/2, sz+4, 2, colKnown, false)
		}
		if r := p.Levels[n.lvl.ID]; r != nil && r.Cleared {
			st := strings.Repeat("★", r.Stars)
			a.Draw(screen, st, n.x-a.Width(st)/2, n.y+int(sz)/2+2, colWarn)
		}
		if !unlocked { // lås: en liten bygel + låda
			vector.DrawFilledRect(screen, float32(n.x)-3, float32(n.y)-1, 6, 5, colPanel, false)
			vector.DrawFilledRect(screen, float32(n.x)-2, float32(n.y)-4, 4, 3, colPanel, false)
			vector.DrawFilledRect(screen, float32(n.x)-1, float32(n.y)-3, 2, 2, colDim, false)
		}
	}
	for _, n := range mains {
		drawNode(n, false)
		for _, s := range sides[n.lvl.ID] {
			drawNode(s, true)
		}
	}
	// Info om vald bana.
	if cur != nil {
		name := cur.Name.Get(UILang) + "  " + cur.Name.Get("ja")
		if cur.IsSide() {
			name = a.T("map.side") + ": " + name
		}
		a.Draw(screen, name, 8, 134, colText)
		fd := level.FinalOf(g.Levels, cur).Destination
		info := fmt.Sprintf("→ %s %s   %s   %s %d", fd.Get("ja"), fd.Get("romaji"),
			strings.Repeat("★", cur.Difficulty)+strings.Repeat("☆", 5-cur.Difficulty), a.T("map.party"), cur.Party)
		if n := len(level.ChainOf(g.Levels, cur.ID)); n > 1 {
			info += fmt.Sprintf("   %s %d", a.T("map.transfers"), n-1)
		}
		if g.State.Current != nil && g.State.Current.LevelID == cur.ID {
			info += "   " + a.T("map.resume")
		}
		a.Draw(screen, info, 8, 146, colDim)
		if !p.Unlocked(g.Levels, cur.ID) {
			a.Draw(screen, a.T("map.locked"), 150, 30, colBad)
		} else if m.msg != "" {
			for i, l := range a.wrapLine(plainLine(m.msg, colBad), ScreenW-158) {
				a.drawLines(screen, []line{l}, 150, 30+i*LineH)
			}
		}
	}
	onoff := a.T("menu.off")
	if g.Wallet.Phone {
		onoff = a.T("menu.on")
	}
	foot := fmt.Sprintf("%s %d  %s %d  %s %d¥", a.T("map.skill_points"), p.SkillPoints, a.T("words.points"), g.Know.Points,
		a.T("hud.cash"), g.Wallet.Cash)
	a.Draw(screen, foot, 8, 30, colDim)
	a.Draw(screen, fmt.Sprintf(a.T("menu.phone"), onoff)+"   "+fmt.Sprintf(a.T("menu.mode"), a.T("mode."+g.Mode.String())), 8, 42, colDim)
	y := 54
	if p.StoryCleared { // efter storyn: oändligt läge och New Game+
		line := a.T("map.endless")
		if b := g.State.BestEndless(); b != nil {
			line += fmt.Sprintf(" (%s)", fmt.Sprintf(a.T("map.endless_best"), b.Score, b.Goals))
		}
		line += "   " + a.T("map.ngplus")
		if p.NGPlus > 0 {
			line += fmt.Sprintf(" (%s)", fmt.Sprintf(a.T("map.ngplus_level"), p.NGPlus))
		}
		a.Draw(screen, line, 8, y, colKnown)
		y += LineH
	}
	if len(g.Profile.Debuffs) > 0 {
		var parts []string
		for _, d := range g.Profile.Debuffs {
			parts = append(parts, fmt.Sprintf("%s (%d)", a.T("debuff."+string(d.Kind)), d.LevelsLeft))
		}
		a.Draw(screen, a.T("hud.debuffs")+": "+strings.Join(parts, ", "), 8, y, colBad)
	}
	a.Draw(screen, a.T("map.hint"), 8, ScreenH-24, colDim)
	a.Draw(screen, fmt.Sprintf("%s (%s)", buildinfo.Version, buildinfo.Mode), 8, ScreenH-12, colDim)
}

// drawLine ritar en tjock linje mellan två punkter.
func drawLine(screen *ebiten.Image, x0, y0, x1, y1 int, col color.Color) {
	vector.StrokeLine(screen, float32(x0), float32(y0), float32(x1), float32(y1), 2, col, false)
}