// Genererar dokumentationens skärmdumpar deterministiskt:
//
//	go run ./tools/shots
//
// Bygger debug-binären, kör den med -script för varje bild och skriver
// PNG:er till doc/img/. Vägarna genom banorna räknas ut med BFS från
// bandatan. Kör om detta när grafik, UI eller banor ändrats, och committa
// bilderna – README och wikin pekar på dem.
//
// På Linux körs spelet på en osynlig skärm (headless Wayfire + Xwayland,
// se headless.go) så att inget fönster syns eller tar fokus. METRO_HEADLESS=0
// stänger av det.
package main

import (
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
	"strings"

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

// demoSave skriver en sparfil med lite progression så att kartan, skills
// och garderoben har något att visa. Används bara av skärmdumparna.
func demoSave(path string) error {
	st := save.New()
	st.Know.Learn("改札")
	st.Know.Learn("出口")
	st.Know.Points = 2
	st.Progress.RecordLevel("001-flygplatsen", true, 3, 941)
	st.Progress.RecordLevel("002-shinjuku", true, 2, 760)
	st.Progress.AddXP(600)
	st.Progress.Items["skin_salaryman"] = true
	st.Progress.Items["geta"] = true
	st.Progress.Items["water_bottle"] = true
	st.Progress.Equipped["body"] = "skin_salaryman"
	st.Progress.Equipped["feet"] = "geta"
	st.Progress.Skills["focus1"] = true
	return save.Store(path, st)
}

type shot struct {
	level  string
	script string   // $OUT ersätts med doc/img-mappen
	args   []string // extra flaggor till spelet
}

// shots byggs i main eftersom vägarna räknas ut från bandatan (BFS), så att
// bilderna överlever ändringar i banorna.
var shots []shot

var demo string

func buildShots(levelsDir string) error {
	l, err := level.LoadFile(filepath.Join(levelsDir, "001-flygplatsen.json"))
	if err != nil {
		return err
	}
	sign := l.Find(level.Sign)[1] // skylten vid spärrarna
	goal := l.Find(level.Platform)[0]
	toSign, err := moves(l, l.SpawnPoint(), sign)
	if err != nil {
		return err
	}
	toGoal, err := moves(l, sign, goal)
	if err != nil {
		return err
	}
	toMachine, err := moves(l, l.SpawnPoint(), l.Find(level.TicketMachine)[0])
	if err != nil {
		return err
	}
	toKiosk, err := moves(l, l.SpawnPoint(), l.Find(level.Kiosk)[0])
	if err != nil {
		return err
	}
	l2, err := level.LoadFile(filepath.Join(levelsDir, "002-shinjuku.json"))
	if err != nil {
		return err
	}
	toMachine2, err := moves(l2, l2.SpawnPoint(), l2.Find(level.TicketMachine)[0])
	if err != nil {
		return err
	}
	l3, err := level.LoadFile(filepath.Join(levelsDir, "003-shibuya.json"))
	if err != nil {
		return err
	}
	toMachine3, err := moves(l3, l3.SpawnPoint(), l3.Find(level.TicketMachine)[0])
	if err != nil {
		return err
	}
	l4, err := level.LoadFile(filepath.Join(levelsDir, "004-tokyo.json"))
	if err != nil {
		return err
	}
	toStairs, err := moves(l4, l4.SpawnPoint(), l4.Find(level.StairsUp)[0])
	if err != nil {
		return err
	}
	l5, err := level.LoadFile(filepath.Join(levelsDir, "005-ueno.json"))
	if err != nil {
		return err
	}
	toPlatform5, err := moves(l5, l5.SpawnPoint(), l5.CorrectPlatform())
	if err != nil {
		return err
	}
	l6, err := level.LoadFile(filepath.Join(levelsDir, "006-ikebukuro.json"))
	if err != nil {
		return err
	}
	toMachine6, err := moves(l6, l6.SpawnPoint(), l6.Find(level.TicketMachine)[0])
	if err != nil {
		return err
	}
	toTrap6, err := moves(l6, l6.SpawnPoint(), l6.Find(level.Platform3)[0]) // Marunouchi: för långt bort
	if err != nil {
		return err
	}
	// Skyltbilderna tas med några kända ord så att markeringen och den
	// delvisa översättningen syns; hjälpen lär sedan in nästa ord.
	known := []string{"-know", "改札,番線,方面", "-seed", "7"}
	shots = []shot{
		{"", "wait 10; shot $OUT/map.png; press l; wait 5; press down; press down; press down; wait 5; shot $OUT/words.png; press l; wait 3; press t; wait 5; press down; wait 3; shot $OUT/skills.png; press t; wait 3; press i; wait 5; shot $OUT/items.png; quit",
			[]string{"-know", "改札,出口,トイレ", "-points", "3", "-save", "$DEMO"}},
		{"001-flygplatsen", toKiosk + "; press b; wait 5; press down; wait 3; shot $OUT/shop.png; quit", []string{"-seed", "7", "-save", "$DEMO"}},
		{"001-flygplatsen", "move right 4; move down 2; wait 5; shot $OUT/level-001.png; quit", nil},
		{"002-shinjuku", "move down 6; move right 4; wait 5; shot $OUT/level-002.png; quit", nil},
		{"001-flygplatsen", toSign + "; wait 5; shot $OUT/sign.png; press h; wait 200; shot $OUT/sign-help.png; wait 200; shot $OUT/sign-learned.png; " + toGoal +
			"; waitphase approaching; wait 200; shot $OUT/approach.png; waittrain; wait 30; shot $OUT/platform.png; press enter; wait 100; pick calm; press enter; wait 40; shot $OUT/ride.png; waitstop; press enter; wait 5; shot $OUT/result.png; quit", known},
		{"001-flygplatsen", toMachine + "; press enter; wait 5; press right; wait 5; shot $OUT/topup.png; quit", []string{"-seed", "7", "-card", "0"}},
		{"002-shinjuku", toMachine2 + "; press enter; wait 5; shot $OUT/ticket.png; quit", []string{"-seed", "7", "-know", "渋谷"}},
		{"003-shibuya", toMachine3 + "; press enter; pick 池袋; press enter; wait 5; press enter; press right; wait 5; shot $OUT/seats.png; quit",
			[]string{"-seed", "7", "-know", "池袋", "-debuffs", "sore_feet"}},
		{"004-tokyo", "wait 10; shot $OUT/floors-b1.png; " + toStairs + "; wait 20; shot $OUT/floors-1f.png; quit", []string{"-seed", "7"}},
		{"005-ueno", "wait 90; shot $OUT/crowd.png; " + toPlatform5 + "; waittrain; wait 5; press enter; wait 20; shot $OUT/cars-alight.png; wait 80; press right; wait 5; shot $OUT/cars.png; quit", []string{"-seed", "7"}},
		{"006-ikebukuro", "move right 2; wait 5; shot $OUT/nav-list.png; quit", []string{"-seed", "7", "-mode", "list"}},
		{"006-ikebukuro", toMachine6 + "; wait 5; shot $OUT/terminal.png; " + "quit", []string{"-seed", "7", "-mode", "signs", "-know", "山手線,番線,方面,新宿,池袋,埼京線"}},
		{"006-ikebukuro", toTrap6 + "; waittrain; wait 5; press enter; wait 100; pick calm; press enter; wait 60; shot $OUT/ride-real.png; waitover; wait 5; shot $OUT/too-far.png; quit", []string{"-seed", "7", "-mode", "signs"}},
		{"", "wait 10; press n; wait 5; shot $OUT/map-signs.png; quit", []string{"-save", "$DEMO"}},
	}
	return nil
}

// moves gör om kortaste vägen mellan två rutor till "move DIR N"-steg.
func moves(l *level.Level, from, to level.Point) (string, error) {
	path := l.Path(from, to, l.CanEnter)
	if path == nil {
		return "", fmt.Errorf("ingen väg %v -> %v i %s", from, to, l.ID)
	}
	var parts []string
	dir, n := "", 0
	flush := func() {
		if n > 0 {
			parts = append(parts, fmt.Sprintf("move %s %d", dir, n))
		}
	}
	for i := 1; i < len(path); i++ {
		if path[i].Z != path[i-1].Z {
			continue // trappan flyttar en till andra våningen i samma steg
		}
		d := dirName(path[i-1], path[i])
		if d != dir {
			flush()
			dir, n = d, 0
		}
		n++
	}
	flush()
	return strings.Join(parts, "; "), nil
}

func dirName(a, b level.Point) string {
	switch {
	case b.X > a.X:
		return "right"
	case b.X < a.X:
		return "left"
	case b.Y > a.Y:
		return "down"
	default:
		return "up"
	}
}

func main() {
	root := repoRoot()
	out := filepath.Join(root, "doc", "img")
	must(os.MkdirAll(out, 0o755))
	demo = filepath.Join(root, "build", "demo-save.json")
	must(os.MkdirAll(filepath.Dir(demo), 0o755))
	must(demoSave(demo))
	must(buildShots(filepath.Join(root, "resources", "data", "levels")))

	build := exec.Command("go", "run", "./tools/build", "-mode", "debug")
	build.Dir, build.Stdout, build.Stderr = root, os.Stdout, os.Stderr
	must(build.Run())

	exe := filepath.Join(root, "build", "debug", "metro-puzzle-jp")
	if runtime.GOOS == "windows" {
		exe += ".exe"
	}
	hl, err := startHeadless(filepath.Join(root, "build"))
	must(err)
	if hl != nil {
		fmt.Printf("» osynlig skärm: %s / %s (inget syns på skrivbordet)\n", hl.wayland, hl.x11)
		defer hl.stop()
	} else {
		fmt.Println("» ingen headless-kompositor (wayfire saknas eller METRO_HEADLESS=0): använder skärmen")
	}
	_ = demo
	for _, s := range shots {
		if len(os.Args) > 1 && !matchesAny(s, os.Args[1:]) {
			continue // `go run ./tools/shots 005 ride` kör bara skott vars namn eller bana innehåller något av orden
		}
		args := []string{"-mute", "-nosave", "-script", strings.ReplaceAll(s.script, "$OUT", out)}
		if s.level != "" {
			args = append(args, "-level", s.level)
		}
		for _, a := range s.args {
			args = append(args, strings.ReplaceAll(a, "$DEMO", demo))
		}
		run := exec.Command(exe, args...)
		run.Dir, run.Stdout, run.Stderr = filepath.Dir(exe), os.Stdout, os.Stderr
		if hl != nil {
			run.Env = hl.env()
		}
		if err := run.Run(); err != nil {
			hl.stop()
			fail(fmt.Errorf("%s: %w", s.script, err))
		}
	}
	fmt.Println("klart:", out)
}

func repoRoot() string {
	dir, _ := os.Getwd()
	for {
		if _, err := os.Stat(filepath.Join(dir, "go.mod")); err == nil {
			return dir
		}
		parent := filepath.Dir(dir)
		if parent == dir {
			fail(fmt.Errorf("hittade ingen go.mod"))
		}
		dir = parent
	}
}

func must(err error) {
	if err != nil {
		fail(err)
	}
}

func fail(err error) {
	fmt.Fprintln(os.Stderr, "shots:", err)
	os.Exit(1)
}

// matchesAny rapporterar om skottets bana eller skript innehåller något av orden.
func matchesAny(s shot, words []string) bool {
	for _, w := range words {
		if strings.Contains(s.level, w) || strings.Contains(s.script, w) {
			return true
		}
	}
	return false
}