feat(文件归并): 归并PDF适配与解析逻辑

2026-10-29 13:56:32 +08:00 · 2026-10-14 09:22:47 +08:00
1 parent b3c4bbc844
commit 961bc52038
@@ -16,14 +16,37 @@ package ofdgo

 import (
 	"context"
+	"fmt"
 	"io"
 	"maps"
+	"net/http"
 	"path"
 	"slices"
+	"strings"

 	"github.com/xiaoqidun/pdfgo"
 )

+// pdfVideoResource 共享视频内容及各播放区域，控制动作按资源关联
+type pdfVideoResource struct {
+	Clip    *pdfgo.MediaClip
+	Screens []*pdfVideoScreen
+}
+
+// pdfVideoScreen 保存播放区域的页面归属及呈现参数
+type pdfVideoScreen struct {
+	Page      int
+	Screen    *pdfgo.ScreenAnnotation
+	Rendition *pdfgo.Rendition
+}
+
+// pdfMovieAction 保存视频控制及可选播放区域，待全部来源收集后关联
+type pdfMovieAction struct {
+	Resource  *pdfVideoResource
+	Target    *pdfVideoScreen
+	Operation int
+}
+
 // mediaFile 复用同一包内文件的输出说明，不合并播放资源及窗口
 // 入参: media 音视频资源
 // 返回: *pdfgo.FileSpecification 待读取的共享文件
@@ -67,3 +90,198 @@ func (n *pdfNavigation) loadMediaFiles(ctx context.Context, files map[string]*pd
 	}
 	return ctx.Err()
 }
+
+// soundAction 保留音量、循环及等待语义，PDF同步播放同时限制交互
+// 入参: action OFD音频动作
+// 返回: *pdfNavigationAction PDF音频动作, error 资源或参数错误
+func (n *pdfNavigation) soundAction(action Sound) (*pdfNavigationAction, error) {
+	volume := 100
+	if action.Volume != nil {
+		volume = *action.Volume
+	}
+	if volume < 0 || volume > 100 {
+		return nil, fmt.Errorf("invalid sound volume")
+	}
+	file := n.audio[action.ResourceID]
+	if file == nil {
+		media, err := n.source.Media(action.ResourceID)
+		if err != nil {
+			return nil, err
+		}
+		if media.Type != "Audio" {
+			return nil, fmt.Errorf("sound resource is not audio: %s", action.ResourceID)
+		}
+		if n.audio == nil {
+			n.audio = make(map[string]*pdfgo.FileSpecification)
+		}
+		file = n.mediaFile(media)
+		n.audio[action.ResourceID] = file
+	}
+	return &pdfNavigationAction{Sound: &pdfgo.SoundAction{
+		Sound: pdfgo.Sound{File: file}, Volume: float64(volume) / 100,
+		Repeat: action.Repeat, Synchronous: action.Synchronous && !action.Repeat,
+	}}, nil
+}
+
+// loadAudio 在绘制后读取自描述音频文件，原始内容不作采样转换
+// 入参: ctx 取消上下文
+// 返回: error 资源读取或取消错误
+func (n *pdfNavigation) loadAudio(ctx context.Context) error {
+	return n.loadMediaFiles(ctx, n.audio)
+}
+
+// movieAction 按OFD第12章选择内嵌区域或浮窗，控制动作不另建播放器
+// 入参: action 视频动作, page 来源页索引，负值表示文档, source 动作来源, pages 输出页面
+// 返回: *pdfNavigationAction 待关联视频动作, error 资源或参数错误
+func (n *pdfNavigation) movieAction(action Movie, page int, source actionSource, pages []RenderDocumentPage) (*pdfNavigationAction, error) {
+	operation := 0
+	switch action.Operator {
+	case "", "Play":
+	case "Stop":
+		operation = 1
+	case "Pause":
+		operation = 2
+	case "Resume":
+		operation = 3
+	default:
+		return nil, fmt.Errorf("invalid movie operator: %s", action.Operator)
+	}
+	resource := n.video[action.ResourceID]
+	if resource == nil {
+		media, err := n.source.Media(action.ResourceID)
+		if err != nil {
+			return nil, err
+		}
+		if media.Type != "Video" {
+			return nil, fmt.Errorf("movie resource is not video: %s", action.ResourceID)
+		}
+		resource = &pdfVideoResource{Clip: &pdfgo.MediaClip{
+			Subtype: "MCD", ContentType: pdfVideoContentType(media),
+			File: n.mediaFile(media),
+		}}
+		if n.video == nil {
+			n.video = make(map[string]*pdfVideoResource)
+		}
+		n.video[action.ResourceID] = resource
+	}
+	value := &pdfMovieAction{Resource: resource, Operation: operation}
+	if operation != 0 {
+		return &pdfNavigationAction{Movie: value}, nil
+	}
+	if len(pages) == 0 || page >= len(pages) {
+		return nil, fmt.Errorf("missing movie playback page")
+	}
+	var rect pdfgo.Rectangle
+	if source.Graphic {
+		if page < 0 || source.Box.W <= 0 || source.Box.H <= 0 {
+			return nil, fmt.Errorf("invalid movie playback region")
+		}
+		const scale = 72.0 / 25.4
+		box := source.Box
+		rect = pdfgo.Rectangle{XMin: box.X * scale, YMin: (pages[page].Box.H - box.Y - box.H) * scale, XMax: (box.X + box.W) * scale, YMax: (pages[page].Box.H - box.Y) * scale}
+	} else {
+		page = 0
+	}
+	for _, screen := range resource.Screens {
+		if screen.Page == page && screen.Screen.Rect == rect {
+			value.Target = screen
+			return &pdfNavigationAction{Movie: value}, nil
+		}
+	}
+	screen := &pdfVideoScreen{Page: page, Screen: &pdfgo.ScreenAnnotation{Rect: rect, Hidden: true}, Rendition: &pdfgo.Rendition{Subtype: "MR", Clip: resource.Clip}}
+	if !source.Graphic {
+		screen.Rendition.Screen = pdfgo.Dictionary{"MH": pdfgo.Dictionary{"W": pdfgo.Integer(0)}, "BE": pdfgo.Dictionary{"F": pdfgo.Dictionary{"D": pdfgo.Array{pdfgo.Integer(640), pdfgo.Integer(360)}, "R": pdfgo.Integer(1)}}}
+	}
+	resource.Screens = append(resource.Screens, screen)
+	value.Target = screen
+	return &pdfNavigationAction{Movie: value}, nil
+}
+
+// values 将资源控制关联到全部播放区域，重新播放前停止同一资源的其他实例
+// 返回: []pdfgo.NavigationAction 有序呈现动作
+func (a *pdfMovieAction) values() []pdfgo.NavigationAction {
+	values := make([]pdfgo.NavigationAction, 0, len(a.Resource.Screens))
+	for _, screen := range a.Resource.Screens {
+		if screen == a.Target {
+			continue
+		}
+		operation := a.Operation
+		if operation == 0 {
+			operation = 1
+		}
+		values = append(values, pdfgo.NavigationAction{Rendition: &pdfgo.RenditionAction{Target: screen.Screen, Operation: operation}})
+	}
+	if a.Target != nil {
+		values = append(values, pdfgo.NavigationAction{Rendition: &pdfgo.RenditionAction{Target: a.Target.Screen, Rendition: a.Target.Rendition}})
+	}
+	return values
+}
+
+// writeVideo 在绘制后读取被播放的视频，原样嵌入并关联输出页面
+// 入参: ctx 取消上下文, pages 输出页引用, options 替换配置
+// 返回: error 资源读取或取消错误
+func (n *pdfNavigation) writeVideo(ctx context.Context, pages []pdfgo.Reference, options *pdfgo.RewriteOptions) error {
+	files := make(map[string]*pdfgo.FileSpecification)
+	for _, id := range slices.Sorted(maps.Keys(n.video)) {
+		if err := ctx.Err(); err != nil {
+			return err
+		}
+		resource := n.video[id]
+		for _, screen := range resource.Screens {
+			if screen.Page < 0 || screen.Page >= len(pages) {
+				return fmt.Errorf("missing movie playback page")
+			}
+			if options.ScreenAnnotations == nil {
+				options.ScreenAnnotations = make(map[pdfgo.Reference][]*pdfgo.ScreenAnnotation)
+			}
+			ref := pages[screen.Page]
+			options.ScreenAnnotations[ref] = append(options.ScreenAnnotations[ref], screen.Screen)
+			files[id] = resource.Clip.File
+		}
+	}
+	if err := n.loadMediaFiles(ctx, files); err != nil {
+		return err
+	}
+	for _, id := range slices.Sorted(maps.Keys(files)) {
+		clip := n.video[id].Clip
+		if clip.ContentType == "" {
+			kind := http.DetectContentType(clip.File.Embedded.Data)
+			if !strings.HasPrefix(kind, "video/") && kind != "application/ogg" {
+				return fmt.Errorf("cannot identify video content type: %s", id)
+			}
+			clip.ContentType = kind
+		}
+	}
+	return ctx.Err()
+}
+
+// pdfVideoContentType 转换明确声明的视频格式，未知格式留待检查文件头
+// 入参: media 视频资源
+// 返回: string 媒体类型，无法确定时为空
+func pdfVideoContentType(media MultiMedia) string {
+	format := strings.ToLower(strings.TrimSpace(media.Format))
+	if format == "" {
+		format = strings.TrimPrefix(strings.ToLower(path.Ext(media.MediaFile)), ".")
+	}
+	switch format {
+	case "mp4", "m4v":
+		return "video/mp4"
+	case "mpeg", "mpg":
+		return "video/mpeg"
+	case "mov", "qt":
+		return "video/quicktime"
+	case "webm":
+		return "video/webm"
+	case "ogv", "ogg":
+		return "video/ogg"
+	case "avi":
+		return "video/x-msvideo"
+	case "wmv":
+		return "video/x-ms-wmv"
+	case "3gp":
+		return "video/3gpp"
+	case "3g2":
+		return "video/3gpp2"
+	}
+	return ""
+}