package vision

import (
	"fmt"
	"image/color"
	"os"
	"os/exec"
	"path/filepath"
	"testing"

	"github.com/fogleman/gg"
)

func TestPreviewer(t *testing.T) {
	// 1. 创建测试环境
	tmpDir, err := os.MkdirTemp("", "vision_test")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(tmpDir)

	videoPath := filepath.Join(tmpDir, "test.mp4")
	webPPath := filepath.Join(tmpDir, "preview.webp")
	oggPath := filepath.Join(tmpDir, "preview.ogg")

	// 2. 模拟生成素材 (生成 5 张纯色帧图片用于合成视频)
	imgPattern := filepath.Join(tmpDir, "frame_%d.png")
	for i := 0; i < 5; i++ {
		dc := gg.NewContext(320, 240)
		dc.SetColor(color.RGBA{uint8(i * 50), 100, 200, 255})
		dc.Clear()
		dc.SavePNG(fmt.Sprintf(imgPattern, i))
	}

	// 使用现有的 vision.Video 逻辑生成视频
	v, err := NewVideo()
	if err != nil {
		t.Fatal(err)
	}
	
	// 这里通过 ffmpeg 拼接图片并添加一个静音音频产生视频
	err = v.CreateVideoFromImages(filepath.Join(tmpDir, "frame_%d.png"), 1, videoPath)
	if err != nil {
		t.Skip("FFmpeg video generation failed, skipping integration test")
	}
	
	// 为测试视频添加静音音频，否则提取音频会失败
	audioPath := filepath.Join(tmpDir, "silent.aac")
	err = exec.Command("ffmpeg", "-f", "lavfi", "-i", "anullsrc=r=44100:cl=mono", "-t", "5", "-c:a", "aac", audioPath).Run()
	if err == nil {
		finalVideo := filepath.Join(tmpDir, "final.mp4")
		exec.Command("ffmpeg", "-i", videoPath, "-i", audioPath, "-c", "copy", finalVideo).Run()
		videoPath = finalVideo
	}

	// 3. 测试 Preview 功能
	t.Run("GenerateImagePreview", func(t *testing.T) {
		imgPath := filepath.Join(tmpDir, "frame_0.png")
		previewImgPath := filepath.Join(tmpDir, "img_preview.webp")
		err := GenerateImagePreview(imgPath, previewImgPath, 100, 100)
		if err != nil {
			t.Errorf("GenerateImagePreview failed: %v", err)
		}
		if _, err := os.Stat(previewImgPath); os.IsNotExist(err) {
			t.Error("Image preview output not created")
		}
	})

	t.Run("GenerateVideoPreview", func(t *testing.T) {
		err := GenerateVideoPreview(videoPath, webPPath, 160, 120)
		if err != nil {
			t.Errorf("GenerateVideoPreview failed: %v", err)
		}
		if _, err := os.Stat(webPPath); os.IsNotExist(err) {
			t.Error("WebP output not created")
		}
	})

	t.Run("GenerateAudioPreview", func(t *testing.T) {
		err := GenerateAudioPreview(videoPath, oggPath)
		if err != nil {
			t.Errorf("GenerateAudioPreview failed: %v", err)
		}
		if _, err := os.Stat(oggPath); os.IsNotExist(err) {
			t.Error("Ogg output not created")
		}
	})
}