kenaito-media-picker/internal/service/scan.go

// Package service 提供 Web 服务端的后台任务编排（媒体库扫描整理）。
package service

import (
	"bufio"
	"errors"
	"fmt"
	"os"
	"path/filepath"
	"regexp"
	"strings"
	"sync"
	"time"

	"kenaito-media-picker/internal/organize"
	"kenaito-media-picker/internal/probe"
	"kenaito-media-picker/internal/scanner"
	"kenaito-media-picker/internal/store"
)

// ScanState 扫描状态
type ScanState string

const (
	ScanIdle    ScanState = "idle"
	ScanRunning ScanState = "running"
	ScanDone    ScanState = "done"
	ScanError   ScanState = "error"
)

// ScanStatus 扫描进度与结果（供前端轮询）
type ScanStatus struct {
	State   ScanState `json:"state"`   // idle/running/done/error
	Message string    `json:"message"` // 简要说明
	Started string    `json:"started"` // 开始时间
	Elapsed int64     `json:"elapsed"` // 已运行秒数
	RootDir string    `json:"rootDir"` // 本次扫描的根目录
	Lines   []string  `json:"lines"`   // 运行日志
}

// ScanService 管理媒体库扫描整理任务（同一时间只允许一次）
type ScanService struct {
	store   *store.Store
	mu      sync.Mutex
	state   ScanState
	msg     string
	started time.Time
	rootDir string
	lines   []string
}

// NewScanService 创建扫描服务；store 可为 nil（数据库不可用时仅不记录媒体信息）
func NewScanService(st *store.Store) *ScanService {
	return &ScanService{store: st, state: ScanIdle}
}

// Start 启动一次扫描整理；已在运行时返回错误。rootDir 为空时默认扫描当前运行目录。
func (s *ScanService) Start(rootDir string) error {
	s.mu.Lock()
	if s.state == ScanRunning {
		s.mu.Unlock()
		return errors.New("扫描整理正在运行中，请等待完成")
	}
	rootDir = resolveRootDir(rootDir)
	if st, err := os.Stat(rootDir); err != nil || !st.IsDir() {
		s.mu.Unlock()
		return fmt.Errorf("扫描目录不存在或不可访问: %s", rootDir)
	}
	s.state = ScanRunning
	s.msg = ""
	s.started = time.Now()
	s.rootDir = rootDir
	s.lines = nil
	s.mu.Unlock()

	go s.run(rootDir)
	return nil
}

// Status 返回当前扫描状态
func (s *ScanService) Status() ScanStatus {
	s.mu.Lock()
	defer s.mu.Unlock()
	elapsed := int64(0)
	if !s.started.IsZero() {
		elapsed = int64(time.Since(s.started).Seconds())
	}
	return ScanStatus{
		State:   s.state,
		Message: s.msg,
		Started: s.started.Format("2006-01-02 15:04:05"),
		Elapsed: elapsed,
		RootDir: s.rootDir,
		Lines:   append([]string{}, s.lines...),
	}
}

// resolveRootDir 解析扫描根目录：空值回退当前工作目录，并做绝对路径归一化
func resolveRootDir(dir string) string {
	if strings.TrimSpace(dir) == "" {
		wd, err := os.Getwd()
		if err == nil {
			return wd
		}
		return "."
	}
	abs, err := filepath.Abs(strings.TrimSpace(dir))
	if err != nil {
		return strings.TrimSpace(dir)
	}
	return abs
}

// run 后台执行：捕获 stdout 日志流式写入 lines，结束后更新状态
func (s *ScanService) run(rootDir string) {
	r, w, err := os.Pipe()
	if err != nil {
		s.finish(ScanError, "创建日志管道失败: "+err.Error())
		return
	}
	oldStdout := os.Stdout
	os.Stdout = w

	done := make(chan struct{})
	go func() {
		defer close(done)
		sc := bufio.NewScanner(r)
		sc.Buffer(make([]byte, 1024*1024), 1024*1024)
		for sc.Scan() {
			line := sanitizeLine(sc.Text())
			if line == "" {
				continue
			}
			s.mu.Lock()
			s.lines = append(s.lines, line)
			s.mu.Unlock()
		}
	}()

	scanErr := s.runScan(rootDir)

	os.Stdout = oldStdout
	_ = w.Close()
	<-done

	if scanErr != nil {
		s.finish(ScanError, scanErr.Error())
		return
	}
	s.finish(ScanDone, "扫描整理完成")
}

// finish 设置最终状态
func (s *ScanService) finish(state ScanState, msg string) {
	s.mu.Lock()
	s.state = state
	s.msg = msg
	s.mu.Unlock()
}

// ansiRe 匹配 ANSI 颜色转义序列
var ansiRe = regexp.MustCompile(`\x1b\[[0-9;]*m`)

// sanitizeLine 清理日志行：去除 ANSI 颜色码，进度条按 \r 分段只保留最后一段
func sanitizeLine(line string) string {
	line = ansiRe.ReplaceAllString(line, "")
	segs := strings.Split(line, "\r")
	return strings.TrimSpace(segs[len(segs)-1])
}

// runScan 执行完整整理流程：扫描 → 过滤 → 释放解码器 → 归类 → 移动
func (s *ScanService) runScan(rootDir string) error {
	pickerDir := filepath.Join(rootDir, filepath.Base(rootDir)+"-picker")
	fmt.Printf("=== 扫描根目录: %s \n", rootDir)
	fmt.Printf("=== 整理输出目录(白名单): %s \n", pickerDir)

	res, err := scanner.Scan(scanner.Options{
		RootDir:   rootDir,
		SkipDir:   pickerDir,
		SkipNames: []string{store.DBFileName, probe.FFprobeExeName},
	})
	if err != nil {
		return fmt.Errorf("扫描失败: %v", err)
	}
	res.Filter()

	// 释放内嵌 ffprobe；失败只跳过媒体整理，图片照常处理
	ffprobePath := ""
	if (len(res.Images) > 0 || len(res.Media) > 0) && probe.HasEmbeddedFFprobe() {
		if err := probe.ReleaseFFprobe(); err != nil {
			fmt.Printf("=== 释放解码器失败, 视频/音频整理将跳过(图片照常处理): %v\n", err)
		} else {
			ffprobePath = probe.FFprobePath()
			defer probe.RemoveFFprobe()
		}
	}

	org := organize.New(pickerDir, ffprobePath, s.store)
	if len(res.Images) > 0 {
		org.ProcessImages(res.Images)
	}
	if len(res.Media) > 0 && ffprobePath != "" {
		org.ProcessMedia(res.Media)
	}
	org.Flush()
	fmt.Println("=== 整理完成")
	return nil
}