package main

import (
	"archive/zip"
	"flag"
	"fmt"
	"io"
	"os"
	"os/exec"
	"path/filepath"
	"strings"

	diskfs "github.com/diskfs/go-diskfs"
	"github.com/diskfs/go-diskfs/disk"
	"github.com/diskfs/go-diskfs/filesystem"
	"github.com/diskfs/go-diskfs/filesystem/iso9660"
)

func main() {
	bin := flag.String("bin", "", "path to darwin Navis binary")
	outDir := flag.String("out", "", "output directory (e.g. dist/navis-release/darwin-arm64)")
	version := flag.String("version", "1.4.1", "CFBundleShortVersionString")
	build := flag.String("build", "", "CFBundleVersion (defaults to -version)")
	arch := flag.String("arch", "arm64", "arch label for volume name")
	flag.Parse()
	if *bin == "" || *outDir == "" {
		fmt.Fprintln(os.Stderr, "usage: packmac -bin <Navis> -out <dir> [-version 2.7.2] [-build 2.7.2.1] [-arch arm64]")
		os.Exit(2)
	}
	bundleVer := *build
	if bundleVer == "" {
		bundleVer = *version
	}
	if err := run(*bin, *outDir, *version, bundleVer, *arch); err != nil {
		fmt.Fprintf(os.Stderr, "packmac: %v\n", err)
		os.Exit(1)
	}
}

func run(binPath, outDir, version, bundleVersion, arch string) error {
	if err := os.MkdirAll(outDir, 0o755); err != nil {
		return err
	}
	stage, err := os.MkdirTemp("", "navis-packmac-*")
	if err != nil {
		return err
	}
	defer os.RemoveAll(stage)

	appRoot := filepath.Join(stage, "Navis.app")
	if err := writeAppBundle(appRoot, binPath, version, bundleVersion, arch); err != nil {
		return err
	}
	if err := signAppBundle(appRoot); err != nil {
		return err
	}
	readme := filepath.Join(stage, "README.txt")
	if err := os.WriteFile(readme, []byte(readmeText(version, arch)), 0o644); err != nil {
		return err
	}
	warnName := archWarningFilename(arch)
	if warnName != "" {
		if err := os.WriteFile(filepath.Join(stage, warnName), []byte(archWarningText(arch)), 0o644); err != nil {
			return err
		}
	}

	zipEntries := []string{"Navis.app", "README.txt"}
	if warnName != "" {
		zipEntries = append(zipEntries, warnName)
	}
	zipPath := filepath.Join(outDir, "Navis.app.zip")
	if err := zipDir(zipPath, stage, zipEntries); err != nil {
		return fmt.Errorf("zip: %w", err)
	}
	fmt.Println("wrote", zipPath)

	dmgPath := filepath.Join(outDir, "Navis.dmg")
	if err := writeNativeOrISODmg(dmgPath, stage, "Navis-"+arch); err != nil {
		return fmt.Errorf("dmg: %w", err)
	}
	fmt.Println("wrote", dmgPath)
	return nil
}

// writeNativeOrISODmg prefers hdiutil (real UDIF DMG) on macOS; ISO9660 breaks .app launch.
func writeNativeOrISODmg(dmgPath, stageDir, volume string) error {
	if _, err := exec.LookPath("hdiutil"); err == nil {
		return writeHdiutilDMG(dmgPath, stageDir, volume)
	}
	entries := []dmgEntry{}
	_ = filepath.Walk(stageDir, func(path string, info os.FileInfo, err error) error {
		if err != nil || info == nil {
			return err
		}
		rel, err := filepath.Rel(stageDir, path)
		if err != nil || rel == "." {
			return err
		}
		// Only top-level items for ISO packer.
		if strings.Contains(rel, string(os.PathSeparator)) {
			return nil
		}
		dst := "/" + filepath.ToSlash(rel)
		entries = append(entries, dmgEntry{path, dst})
		return nil
	})
	return writeDMG(dmgPath, entries, volume)
}

func writeHdiutilDMG(dmgPath, stageDir, volume string) error {
	_ = os.Remove(dmgPath)
	vol := sanitizeVol(volume)
	cmd := exec.Command("hdiutil", "create",
		"-volname", vol,
		"-srcfolder", stageDir,
		"-ov",
		"-format", "UDZO",
		dmgPath,
	)
	out, err := cmd.CombinedOutput()
	if err != nil {
		return fmt.Errorf("hdiutil: %w: %s", err, strings.TrimSpace(string(out)))
	}
	// Re-sign after packaging is unnecessary for UDZO copy of already-signed .app,
	// but clear quarantine on the dmg itself if present.
	_ = exec.Command("xattr", "-cr", dmgPath).Run()
	return nil
}

func writeAppBundle(appRoot, binPath, version, bundleVersion, arch string) error {
	macOSDir := filepath.Join(appRoot, "Contents", "MacOS")
	resDir := filepath.Join(appRoot, "Contents", "Resources")
	if err := os.MkdirAll(macOSDir, 0o755); err != nil {
		return err
	}
	if err := os.MkdirAll(resDir, 0o755); err != nil {
		return err
	}
	archPriority := architecturePriorityXML(arch)
	plist := fmt.Sprintf(`<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  <key>CFBundleExecutable</key><string>Navis</string>
  <key>CFBundleIdentifier</key><string>win.evilfox.navis</string>
  <key>CFBundleName</key><string>Navis</string>
  <key>CFBundleDisplayName</key><string>Navis</string>
  <key>CFBundleIconFile</key><string>AppIcon</string>
  <key>CFBundlePackageType</key><string>APPL</string>
  <key>CFBundleShortVersionString</key><string>%s</string>
  <key>CFBundleVersion</key><string>%s</string>
  <key>LSMinimumSystemVersion</key><string>11.0</string>
  <key>NSHighResolutionCapable</key><true/>
  <key>CFBundleInfoDictionaryVersion</key><string>6.0</string>%s
</dict>
</plist>
`, version, bundleVersion, archPriority)
	if err := os.WriteFile(filepath.Join(appRoot, "Contents", "Info.plist"), []byte(plist), 0o644); err != nil {
		return err
	}
	if err := os.WriteFile(filepath.Join(appRoot, "Contents", "PkgInfo"), []byte("APPL????"), 0o644); err != nil {
		return err
	}
	if icns := findAsset("navis.icns"); icns != "" {
		if err := copyFile(icns, filepath.Join(resDir, "AppIcon.icns"), 0o644); err != nil {
			return fmt.Errorf("app icon: %w", err)
		}
	}
	dest := filepath.Join(macOSDir, "Navis")
	if err := copyFile(binPath, dest, 0o755); err != nil {
		return err
	}
	return nil
}

func signAppBundle(appRoot string) error {
	if _, err := exec.LookPath("codesign"); err != nil {
		return nil
	}
	// NAVIS_CODESIGN_IDENTITY=Developer ID Application: … for release; default ad-hoc "-".
	identity := strings.TrimSpace(os.Getenv("NAVIS_CODESIGN_IDENTITY"))
	if identity == "" {
		identity = "-"
	}
	cmd := exec.Command("codesign", "-s", identity, "--force", "--deep", "--options", "runtime", appRoot)
	out, err := cmd.CombinedOutput()
	if err != nil {
		cmd = exec.Command("codesign", "-s", identity, "--force", "--deep", appRoot)
		out, err = cmd.CombinedOutput()
		if err != nil {
			return fmt.Errorf("codesign %s: %w: %s", appRoot, err, strings.TrimSpace(string(out)))
		}
	}
	_ = exec.Command("xattr", "-cr", appRoot).Run()
	return nil
}

type dmgEntry struct {
	srcPath string
	dstPath string
}

func writeDMG(dmgPath string, files []dmgEntry, volume string) error {
	_ = os.Remove(dmgPath)
	var need int64
	for _, f := range files {
		if fi, err := os.Stat(f.srcPath); err == nil && !fi.IsDir() {
			need += fi.Size()
		} else if sz, err := dirSize(f.srcPath); err == nil {
			need += sz
		}
	}
	need += 4 * 1024 * 1024
	if need < 12*1024*1024 {
		need = 12 * 1024 * 1024
	}
	need = ((need + 2047) / 2048) * 2048

	mydisk, err := diskfs.Create(dmgPath, need, diskfs.SectorSizeDefault)
	if err != nil {
		return err
	}
	mydisk.LogicalBlocksize = 2048
	fs, err := mydisk.CreateFilesystem(disk.FilesystemSpec{
		Partition:   0,
		FSType:      filesystem.TypeISO9660,
		VolumeLabel: sanitizeVol(volume),
	})
	if err != nil {
		return err
	}

	for _, f := range files {
		info, err := os.Stat(f.srcPath)
		if err != nil {
			_ = fs.Close()
			return err
		}
		if info.IsDir() {
			if err := copyTreeToISO(fs, f.srcPath, f.dstPath); err != nil {
				_ = fs.Close()
				return err
			}
			continue
		}
		if err := writeISOFile(fs, f.dstPath, f.srcPath, 0o644); err != nil {
			_ = fs.Close()
			return err
		}
	}

	iso, ok := fs.(*iso9660.FileSystem)
	if !ok {
		_ = fs.Close()
		return fmt.Errorf("not iso9660")
	}
	if err := iso.Finalize(iso9660.FinalizeOptions{
		RockRidge:          true,
		Joliet:             true,
		DeepDirectories:    true,
		VolumeIdentifier:   sanitizeVol(volume),
		PublisherIdentifier: "Navis",
	}); err != nil {
		return err
	}
	return fs.Close()
}

func copyTreeToISO(fs filesystem.FileSystem, srcRoot, dstRoot string) error {
	return filepath.Walk(srcRoot, func(path string, info os.FileInfo, err error) error {
		if err != nil {
			return err
		}
		rel, err := filepath.Rel(srcRoot, path)
		if err != nil {
			return err
		}
		rel = filepath.ToSlash(rel)
		dst := dstRoot
		if rel != "." {
			dst = dstRoot + "/" + rel
		}
		if info.IsDir() {
			if dst == dstRoot {
				return fs.Mkdir(dst)
			}
			return fs.Mkdir(dst)
		}
		mode := info.Mode()
		if mode&0o111 != 0 || strings.HasSuffix(rel, "MacOS/Navis") || strings.HasSuffix(rel, "MacOS\\Navis") {
			mode = 0o755
		} else {
			mode = 0o644
		}
		return writeISOFile(fs, dst, path, mode)
	})
}

func writeISOFile(fs filesystem.FileSystem, dst, src string, mode os.FileMode) error {
	in, err := os.Open(src)
	if err != nil {
		return err
	}
	defer in.Close()
	rw, err := fs.OpenFile(dst, os.O_CREATE|os.O_RDWR|os.O_TRUNC)
	if err != nil {
		return err
	}
	if _, err := io.Copy(rw, in); err != nil {
		_ = rw.Close()
		return err
	}
	if err := rw.Close(); err != nil {
		return err
	}
	if err := fs.Chmod(dst, mode); err != nil {
		_ = err // best-effort
	}
	return nil
}

func zipDir(zipPath, stage string, entries []string) error {
	_ = os.Remove(zipPath)
	f, err := os.Create(zipPath)
	if err != nil {
		return err
	}
	defer f.Close()
	zw := zip.NewWriter(f)
	defer zw.Close()

	for _, name := range entries {
		root := filepath.Join(stage, name)
		info, err := os.Stat(root)
		if err != nil {
			return err
		}
		if !info.IsDir() {
			if err := addZipFile(zw, root, name, 0o644); err != nil {
				return err
			}
			continue
		}
		err = filepath.Walk(root, func(path string, fi os.FileInfo, err error) error {
			if err != nil {
				return err
			}
			rel, err := filepath.Rel(stage, path)
			if err != nil {
				return err
			}
			rel = filepath.ToSlash(rel)
			if fi.IsDir() {
				_, err := zw.Create(rel + "/")
				return err
			}
			mode := os.FileMode(0o644)
			if strings.Contains(rel, "Contents/MacOS/") {
				mode = 0o755
			}
			return addZipFile(zw, path, rel, mode)
		})
		if err != nil {
			return err
		}
	}
	return nil
}

func addZipFile(zw *zip.Writer, path, name string, mode os.FileMode) error {
	h, err := zip.FileInfoHeader(mustStat(path))
	if err != nil {
		return err
	}
	h.Name = name
	h.Method = zip.Deflate
	h.SetMode(mode)
	w, err := zw.CreateHeader(h)
	if err != nil {
		return err
	}
	in, err := os.Open(path)
	if err != nil {
		return err
	}
	defer in.Close()
	_, err = io.Copy(w, in)
	return err
}

func mustStat(path string) os.FileInfo {
	fi, err := os.Stat(path)
	if err != nil {
		panic(err)
	}
	return fi
}

// findAsset locates a file under assets/ relative to cwd or the packmac binary.
func findAsset(name string) string {
	candidates := []string{
		filepath.Join("assets", name),
	}
	if exe, err := os.Executable(); err == nil {
		dir := filepath.Dir(exe)
		candidates = append(candidates,
			filepath.Join(dir, "..", "..", "assets", name),
			filepath.Join(dir, "..", "assets", name),
			filepath.Join(dir, "assets", name),
		)
	}
	if wd, err := os.Getwd(); err == nil {
		candidates = append(candidates, filepath.Join(wd, "assets", name))
	}
	for _, c := range candidates {
		if st, err := os.Stat(c); err == nil && !st.IsDir() {
			abs, err := filepath.Abs(c)
			if err == nil {
				return abs
			}
			return c
		}
	}
	return ""
}

func copyFile(src, dst string, mode os.FileMode) error {
	in, err := os.Open(src)
	if err != nil {
		return err
	}
	defer in.Close()
	out, err := os.OpenFile(dst, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, mode)
	if err != nil {
		return err
	}
	defer out.Close()
	_, err = io.Copy(out, in)
	return err
}

func dirSize(root string) (int64, error) {
	var n int64
	err := filepath.Walk(root, func(_ string, info os.FileInfo, err error) error {
		if err != nil {
			return err
		}
		if !info.IsDir() {
			n += info.Size()
		}
		return nil
	})
	return n, err
}

func fileSize(path string) (int64, error) {
	fi, err := os.Stat(path)
	if err != nil {
		return 0, err
	}
	return fi.Size(), nil
}

func sanitizeVol(s string) string {
	s = strings.ToUpper(s)
	s = strings.Map(func(r rune) rune {
		if (r >= 'A' && r <= 'Z') || (r >= '0' && r <= '9') || r == '-' || r == '_' {
			return r
		}
		return '-'
	}, s)
	if len(s) > 32 {
		s = s[:32]
	}
	if s == "" {
		s = "NAVIS"
	}
	return s
}

func readmeText(version, arch string) string {
	switch arch {
	case "universal":
		return fmt.Sprintf(`Navis %s for macOS (универсальная сборка)

Подходит для Apple Silicon (M1/M2/M3/M4) и Intel Mac.

1) Перетащите Navis.app в Программы (Applications)
2) При первом запуске, если macOS блокирует:
   xattr -dr com.apple.quarantine /Applications/Navis.app
3) В Терминале:
   /Applications/Navis.app/Contents/MacOS/Navis init
   /Applications/Navis.app/Contents/MacOS/Navis install-core
   /Applications/Navis.app/Contents/MacOS/Navis connect

Магазин: https://evilfox.win/
`, version)
	case "arm64":
		return fmt.Sprintf(`Navis %s for macOS (Apple Silicon: M1/M2/M3/M4)

⚠️ Только для Mac с чипом Apple Silicon (arm64).
На Intel Mac скачайте darwin-amd64 или darwin-universal.

1) Перетащите Navis.app в Программы
2) xattr -dr com.apple.quarantine /Applications/Navis.app
3) /Applications/Navis.app/Contents/MacOS/Navis connect

Магазин: https://evilfox.win/
`, version)
	case "amd64":
		return fmt.Sprintf(`Navis %s for macOS (Intel x86_64)

⚠️ Только для Intel Mac.
На Mac M1/M2/M3/M4 эта сборка НЕ запустится — скачайте darwin-arm64 или darwin-universal.

1) Перетащите Navis.app в Программы
2) xattr -dr com.apple.quarantine /Applications/Navis.app
3) /Applications/Navis.app/Contents/MacOS/Navis connect

Магазин: https://evilfox.win/
`, version)
	default:
		return fmt.Sprintf(`Navis %s for macOS (%s)

1) Drag Navis.app to Applications
2) xattr -dr com.apple.quarantine /Applications/Navis.app
3) /Applications/Navis.app/Contents/MacOS/Navis connect
`, version, arch)
	}
}

func archWarningFilename(arch string) string {
	switch arch {
	case "amd64":
		return "ТОЛЬКО-INTEL-MAC.txt"
	case "arm64":
		return "ТОЛЬКО-APPLE-SILICON.txt"
	default:
		return ""
	}
}

func archWarningText(arch string) string {
	switch arch {
	case "amd64":
		return `ВНИМАНИЕ

Эта сборка Navis только для Intel Mac (x86_64).

Если у вас Mac mini / MacBook с чипом M1, M2, M3 или M4 —
закройте этот диск и скачайте универсальный DMG:

https://git.evilfox.cc/test2/navi/raw/branch/main/dist/navis-release/darwin-universal/Navis.dmg

Или arm64:
https://git.evilfox.cc/test2/navi/raw/branch/main/dist/navis-release/darwin-arm64/Navis.dmg
`
	case "arm64":
		return `ВНИМАНИЕ

Эта сборка Navis только для Apple Silicon (M1/M2/M3/M4).

Если у вас Intel Mac — скачайте darwin-amd64 или универсальный DMG:

https://git.evilfox.cc/test2/navi/raw/branch/main/dist/navis-release/darwin-universal/Navis.dmg
`
	default:
		return ""
	}
}

func architecturePriorityXML(arch string) string {
	switch arch {
	case "universal":
		return `
  <key>LSArchitecturePriority</key>
  <array>
    <string>arm64</string>
    <string>x86_64</string>
  </array>`
	case "arm64":
		return `
  <key>LSArchitecturePriority</key>
  <array><string>arm64</string></array>
  <key>LSRequiresNativeExecution</key>
  <true/>`
	case "amd64":
		return `
  <key>LSArchitecturePriority</key>
  <array><string>x86_64</string></array>`
	default:
		return ""
	}
}