feat: add fission package download

backend/app/services/fission_package_exporter.py

@@ -0,0 +1,156 @@
+"""
+fission_package_exporter.py — 裂变笔记包下载
+
+把 FissionNote 表中的 N 套裂变结果打成 zip：
+note_01/文案.txt + 生成图 + 发布清单 + 说明。
+"""
+from __future__ import annotations
+
+import json
+import logging
+import shutil
+import zipfile
+from datetime import datetime
+from pathlib import Path
+from typing import Any
+
+from app.core.config import get_settings
+
+logger = logging.getLogger(__name__)
+
+
+def _safe_name(value: str | None, fallback: str = "img") -> str:
+    raw = (value or fallback).strip() or fallback
+    return "".join(c if c.isalnum() or c in ("-", "_") else "_" for c in raw)[:40]
+
+
+def _resolve_upload_path(url: str, upload_root: Path) -> Path:
+    if url.startswith("/uploads/"):
+        return upload_root / url.removeprefix("/uploads/")
+    if url.startswith("uploads/"):
+        return upload_root / url.removeprefix("uploads/")
+    return Path(url)
+
+
+def _loads_json(value: str | None, fallback: Any) -> Any:
+    try:
+        return json.loads(value) if value else fallback
+    except (TypeError, ValueError):
+        return fallback
+
+
+def _write_note_text(note_dir: Path, note: dict[str, Any]) -> None:
+    tags = note.get("tags") or []
+    if not isinstance(tags, list):
+        tags = []
+    image_plan = note.get("imagePlan") or []
+    lines = [
+        f"【标题】{note.get('title', '')}",
+        "",
+        "【封面钩子】",
+        str(note.get("coverTitle") or ""),
+        "",
+        "【正文】",
+        str(note.get("content") or ""),
+    ]
+    if tags:
+        lines += ["", "【标签】", " ".join(str(t) for t in tags)]
+    if image_plan:
+        lines += ["", "【图片排版说明】"]
+        for idx, plan in enumerate(image_plan, start=1):
+            if not isinstance(plan, dict):
+                continue
+            parts = [
+                f"{idx}. {plan.get('role') or f'图{idx}'}",
+                f"标题：{plan.get('title') or ''}",
+                f"叠字：{plan.get('overlayText') or ''}",
+                f"画面：{plan.get('text') or ''}",
+            ]
+            lines.append(" / ".join(parts))
+    (note_dir / "文案.txt").write_text("\n".join(lines), encoding="utf-8")
+
+
+def build_fission_package(ft, rows: list) -> str:
+    """生成裂变下载 zip，返回 zip 本地路径。"""
+    upload_root = Path(get_settings().UPLOAD_ABS_ROOT).resolve()
+    package_dir = upload_root / "packages" / "fission" / str(ft.workspace_id) / str(ft.id)
+    if package_dir.exists():
+        shutil.rmtree(package_dir)
+    package_dir.mkdir(parents=True, exist_ok=True)
+
+    note_dirs: list[Path] = []
+    checklist: list[str] = [
+        "📋 裂变笔记发布清单",
+        f"生成时间：{datetime.now().strftime('%Y-%m-%d %H:%M')}",
+        f"裂变ID：{ft.id}",
+        f"参考程度：{ft.reference_level}",
+        "",
+    ]
+    missing_images: list[str] = []
+
+    for idx, row in enumerate(rows, start=1):
+        note = _loads_json(row.note_json, {})
+        images = _loads_json(row.images_json, [])
+        if not isinstance(note, dict):
+            note = {}
+        if not isinstance(images, list):
+            images = []
+
+        note_dir = package_dir / f"note_{idx:02d}"
+        note_dir.mkdir(parents=True, exist_ok=True)
+        note_dirs.append(note_dir)
+        _write_note_text(note_dir, note)
+
+        copied = 0
+        expected = 0
+        for img_idx, img in enumerate(images, start=1):
+            if not isinstance(img, dict) or img.get("error"):
+                continue
+            url = img.get("url") or img.get("image_url")
+            if not url:
+                continue
+            expected += 1
+            src = _resolve_upload_path(str(url), upload_root)
+            if not src.is_file():
+                missing_images.append(f"note_{idx:02d}: {url}")
+                continue
+            role = _safe_name(str(img.get("role") or f"img_{img_idx}"))
+            seq = img.get("seq") or img_idx
+            dst = note_dir / f"{int(seq):02d}_{role}.jpg"
+            shutil.copyfile(src, dst)
+            copied += 1
+
+        if expected and copied == 0:
+            raise ValueError(f"第 {idx} 套裂变图片读取失败，拒绝生成无图下载包")
+
+        title = str(note.get("title") or f"第{idx}套")
+        checklist.append(
+            f"note_{idx:02d}  标题：{title[:32]}  图片数：{copied}  分数：{row.score}"
+        )
+
+    if not note_dirs:
+        raise ValueError("裂变结果为空，无法下载")
+
+    if missing_images:
+        checklist += ["", "图片读取提示："]
+        checklist += [f"- {item}" for item in missing_images[:20]]
+        if len(missing_images) > 20:
+            checklist.append(f"- 另有 {len(missing_images) - 20} 张图片缺失")
+    checklist += [
+        "",
+        "使用说明：",
+        "- 每个 note_xx 文件夹是一套可独立发布的裂变笔记。",
+        "- 文案.txt 内含标题、封面钩子、正文、标签和图片排版说明。",
+        "- 图片按 01/02/03 顺序上传，避免传错序。",
+    ]
+    (package_dir / "📋裂变发布清单.txt").write_text("\n".join(checklist), encoding="utf-8")
+
+    zip_path = package_dir / "fission_package.zip"
+    with zipfile.ZipFile(zip_path, "w", zipfile.ZIP_DEFLATED) as zf:
+        for note_dir in note_dirs:
+            for fpath in sorted(note_dir.iterdir()):
+                zf.write(fpath, arcname=f"{note_dir.name}/{fpath.name}")
+        zf.write(package_dir / "📋裂变发布清单.txt", arcname="📋裂变发布清单.txt")
+
+    logger.info("fission package built: %s notes=%d", zip_path, len(note_dirs))
+    return str(zip_path)