package recovery

import (
	"context"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"strconv"
	"strings"
	"sync"
)

type QobuzDL struct {
	Path      string
	OutputDir string
	Username  string
	Password  string
	Quality   int
}

var cachedBinaries sync.Map

func (d QobuzDL) DownloadAlbum(ctx context.Context, albumID string) error {
	albumID = strings.TrimSpace(albumID)
	if albumID == "" {
		return fmt.Errorf("album id must not be empty")
	}
	url := fmt.Sprintf("https://play.qobuz.com/album/%s", albumID)

	args := []string{}
	if strings.TrimSpace(d.OutputDir) != "" {
		args = append(args, "--output", d.OutputDir)
	}
	if d.Quality > 0 {
		args = append(args, "--quality", strconv.Itoa(d.Quality))
	}
	if strings.TrimSpace(d.Username) != "" {
		args = append(args, "--user", strings.TrimSpace(d.Username))
	}
	if strings.TrimSpace(d.Password) != "" {
		args = append(args, "--pass", d.Password)
	}
	args = append(args, "url", url)

	name, cmdArgs, workdir, err := resolveCommand(ctx, strings.TrimSpace(d.Path), args)
	if err != nil {
		return err
	}
	cmd := exec.CommandContext(ctx, name, cmdArgs...)
	if workdir != "" {
		cmd.Dir = workdir
	}
	out, err := cmd.CombinedOutput()
	if err != nil {
		return fmt.Errorf("qobuz-dl failed: %w: %s", err, strings.TrimSpace(string(out)))
	}
	return nil
}

func resolveCommand(ctx context.Context, path string, args []string) (name string, cmdArgs []string, workdir string, err error) {
	if path == "" {
		return "qobuz-dl", args, "", nil
	}

	info, err := os.Stat(path)
	if err == nil && info.IsDir() {
		bin, err := ensureBuiltBinary(ctx, path)
		if err != nil {
			return "", nil, "", err
		}
		return bin, args, "", nil
	}

	if filepath.Base(path) == "." {
		dir := filepath.Dir(path)
		bin, err := ensureBuiltBinary(ctx, dir)
		if err != nil {
			return "", nil, "", err
		}
		return bin, args, "", nil
	}

	return path, args, "", nil
}

func ensureBuiltBinary(ctx context.Context, dir string) (string, error) {
	dir = filepath.Clean(dir)
	if v, ok := cachedBinaries.Load(dir); ok {
		if bin, ok := v.(string); ok && strings.TrimSpace(bin) != "" {
			if _, err := os.Stat(bin); err == nil {
				return bin, nil
			}
		}
	}

	tmpDir := filepath.Join(os.TempDir(), "navimigrate-qobuzdl")
	if err := os.MkdirAll(tmpDir, 0o755); err != nil {
		return "", fmt.Errorf("create temp build directory: %w", err)
	}

	out := filepath.Join(tmpDir, "qobuz-dl")
	build := exec.CommandContext(ctx, "go", "build", "-o", out, ".")
	build.Dir = dir
	b, err := build.CombinedOutput()
	if err != nil {
		return "", fmt.Errorf("build qobuz-dl in %s: %w: %s", dir, err, strings.TrimSpace(string(b)))
	}

	cachedBinaries.Store(dir, out)
	return out, nil
}