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/lang"
)

// WordsScene är ordlistan/språkträdet: alla ord i ordboken, vad spelaren
// kan, framsteg på resten, och möjligheten att lägga språkpoäng på valfria
// ord. Blir ett riktigt träd med skills i M8.
type WordsScene struct {
	back    Scene
	entries []*lang.Entry
	sel     int
	top     int
	msg     string
}

const wordsRows = 9

// NewWordsScene listar ordboken sorterad på tier och ord.
func NewWordsScene(a *Assets, back Scene) *WordsScene {
	var es []*lang.Entry
	for _, w := range a.Dict.Words() {
		es = append(es, a.Dict.Lookup(w))
	}
	sort.Slice(es, func(i, j int) bool {
		if es[i].Tier != es[j].Tier {
			return es[i].Tier < es[j].Tier
		}
		return es[i].Word < es[j].Word
	})
	return &WordsScene{back: back, entries: es}
}

func (w *WordsScene) Update(g *Game) error {
	if backJustPressed() || wordsJustPressed() {
		g.SetScene(w.back)
		return nil
	}
	if n := len(w.entries); n > 0 {
		w.sel = (w.sel + menuMove() + n) % n
		if w.sel < w.top {
			w.top = w.sel
		}
		if w.sel >= w.top+wordsRows {
			w.top = w.sel - wordsRows + 1
		}
		if confirmJustPressed() {
			e := w.entries[w.sel]
			switch {
			case g.Know.Knows(e.Word):
				w.msg = g.Assets.T("words.already")
			case g.Know.Buy(e):
				w.msg = fmt.Sprintf(g.Assets.T("words.bought"), e.Word, e.Translation(UILang))
			default:
				w.msg = fmt.Sprintf(g.Assets.T("words.too_expensive"), lang.WordCost(e))
			}
		}
	}
	return nil
}

func (w *WordsScene) Draw(g *Game, screen *ebiten.Image) {
	a := g.Assets
	k := g.Know
	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("words.title"), 8, 5, colText)
	hdr := fmt.Sprintf("%s %d   %s Lv%d  %d/%d %s", a.T("words.points"), k.Points, a.T("hud.japanese"),
		k.Level(), k.Count(), len(w.entries), a.T("hud.words"))
	a.Draw(screen, hdr, ScreenW-8-a.Width(hdr), 6, colKnown)

	y0 := 30
	for i := w.top; i < len(w.entries) && i < w.top+wordsRows; i++ {
		e := w.entries[i]
		y := y0 + (i-w.top)*LineH
		if i == w.sel {
			vector.DrawFilledRect(screen, 4, float32(y-1), ScreenW-8, LineH, colBar, false)
		}
		status, scol := strings.Repeat("●", lang.WordCost(e)), colDim
		if k.CanBuy(e) {
			scol = colKnown
		}
		wcol := colText
		switch {
		case k.Knows(e.Word):
			status, scol, wcol = "✓", colGood, colKnown
		case k.ProgressOf(e.Word) > 0:
			status, scol = fmt.Sprintf("%d/%d", k.ProgressOf(e.Word), lang.ProgressToLearn), colWarn
		}
		a.Draw(screen, e.Word, 8, y, wcol)
		a.Draw(screen, e.Romaji, 92, y, colDim)
		a.Draw(screen, e.Translation(UILang), 180, y, colText)
		a.Draw(screen, status, ScreenW-8-a.Width(status), y, scol)
	}
	// rullningsindikator
	if len(w.entries) > wordsRows {
		a.Draw(screen, fmt.Sprintf("%d-%d / %d", w.top+1, min(len(w.entries), w.top+wordsRows), len(w.entries)), 8, ScreenH-38, colDim)
	}
	if w.msg != "" {
		a.Draw(screen, w.msg, 8, ScreenH-26, colKnown)
	}
	a.Draw(screen, a.T("words.hint"), 8, ScreenH-13, colDim)
}