gen2d/backend/tools/test_prompt_to_gif.go

//go:build ignore

package main

import (
	"bytes"
	"context"
	"fmt"
	"image"
	"image/png"
	"os"

	"gen2d/internal/config"
	"gen2d/internal/service"
	"gen2d/pkg/gifmaker"
	"gen2d/pkg/splitsprite"
)

func main() {
	cfg := config.Load()
	service.InitLLMConfig(cfg.LLM)
	service.InitImageGenConfig(cfg.ImageGen)

	ctx := context.Background()

	// 1. PromptAgent 优化提示词
	fmt.Println("=== Step 1: Optimize prompt via PromptAgent ===")
	agentIn := service.PromptAgentInput{
		Tags:      []string{"像素", "横版动作", "大剑战士", "精灵表", "4x4网格"},
		AssetType: "sprite",
		Prompt:    "生成一个2D横版动作游戏角色的连续攻击连招精灵表，侧视角，4行4列网格排列",
		UserNote:  "角色为持大剑的战士，连招包含4段攻击：横斩→上挑→跳劈→终结重击。每段攻击4帧关键帧，共16帧，按4行×4列网格排列。帧间留8-16px纯白间隙(#FFFFFF)。要求动作流畅有力量感，大剑挥舞轨迹清晰",
	}
	out, err := service.RunPromptAgent(ctx, agentIn)
	if err != nil {
		fatalf("PromptAgent failed: %v", err)
	}
	fmt.Printf("Optimized prompt:\n%s\n\n", out.Prompt)

	// 2. 调用文生图 API
	fmt.Println("=== Step 2: Generate sprite sheet via image API ===")
	params := service.AssetParams{
		Resolution: 1536,
		Format:     "spritesheet",
	}
	images, err := service.GenerateImages(ctx, out.Prompt, params)
	if err != nil {
		fatalf("GenerateImages failed: %v", err)
	}
	if len(images) == 0 {
		fatalf("no images generated")
	}
	fmt.Printf("Generated %d image(s), size=%dx%d\n", len(images), images[0].Width, images[0].Height)

	os.MkdirAll("test_output", 0755)

	// 保存原始精灵表
	sheetPath := "test_output/sprite_sheet.png"
	if err := os.WriteFile(sheetPath, images[0].Data, 0644); err != nil {
		fatalf("save sheet: %v", err)
	}
	fmt.Printf("Saved sprite sheet → %s (%d bytes)\n", sheetPath, len(images[0].Data))

	// 3. splitsprite: 洗白底 → 波谷投影拆分 → 有效像素≥40% → 裁切像素边界 → 统一最大分辨率居中
	fmt.Println("\n=== Step 3: Wash white bg → valley projection split → trim → center align ===")
	sheetImg, err := decodePNG(images[0].Data)
	if err != nil {
		fatalf("decode sheet: %v", err)
	}
	opts := splitsprite.DefaultOptions() // WhiteBg=true, MinFillRatio=0.4, CenterAlign=true
	frames, err := splitsprite.Process(sheetImg, opts)
	if err != nil {
		fatalf("split failed: %v", err)
	}
	fmt.Printf("Detected %d frames\n", len(frames))

	// 保存单帧
	for i, f := range frames {
		fn := fmt.Sprintf("test_output/frame_%03d.png", i)
		if err := savePNG(fn, f); err != nil {
			fatalf("save frame %d: %v", i, err)
		}
	}
	fmt.Printf("Saved %d frames → test_output/frame_*.png\n", len(frames))

	// 4. 生成 GIF 预览
	fmt.Println("\n=== Step 4: Generate GIF preview ===")
	gifPath := "test_output/preview.gif"
	if err := gifmaker.Save(gifPath, frames, nil); err != nil {
		fatalf("generate GIF: %v", err)
	}
	fmt.Printf("GIF preview → %s (%d frames)\n", gifPath, len(frames))

	fmt.Println("\n=== Done ===")
	fmt.Println("Output files:")
	fmt.Println("  test_output/sprite_sheet.png  — original sprite sheet")
	fmt.Println("  test_output/frame_*.png       — individual frames")
	fmt.Println("  test_output/preview.gif       — animated GIF preview")
}

func decodePNG(data []byte) (image.Image, error) {
	img, _, err := image.Decode(bytes.NewReader(data))
	if err != nil {
		return nil, err
	}
	return img, nil
}

func savePNG(path string, img image.Image) error {
	f, err := os.Create(path)
	if err != nil {
		return err
	}
	defer f.Close()
	return png.Encode(f, img)
}

func fatalf(format string, args ...interface{}) {
	fmt.Fprintf(os.Stderr, format+"\n", args...)
	os.Exit(1)
}