from __future__ import annotations

from dataclasses import dataclass, field
from datetime import UTC, datetime
from typing import Any
from uuid import uuid4


@dataclass(slots=True)
class GeneratedVideo:
    id: str
    project_id: str
    generation_task_id: str
    name: str
    file_url: str
    file_size: int
    duration: float
    width: int
    height: int
    fps: float
    user_id: str = ""
    thumbnail_url: str | None = None
    status: str = "completed"
    review_status: str = "pending_review"
    generation_params: dict[str, Any] = field(default_factory=dict)
    video_fingerprint: dict[str, Any] | None = None
    is_duplicate: bool = False
    duplicate_of: str | None = None
    duplicate_rate: float | None = None
    match_count: int | None = None
    visual_similarity: float | None = None
    generated_at: datetime = field(default_factory=lambda: datetime.now(UTC))
    created_at: datetime = field(default_factory=lambda: datetime.now(UTC))

    @classmethod
    def create(
        cls,
        project_id: str,
        generation_task_id: str,
        name: str,
        file_url: str,
        *,
        user_id: str = "",
        file_size: int = 0,
        duration: float = 0.0,
        width: int = 0,
        height: int = 0,
        fps: float = 0.0,
        thumbnail_url: str | None = None,
        generation_params: dict[str, Any] | None = None,
    ) -> "GeneratedVideo":
        # project_id / generation_task_id 允许为空：AI数字人等无项目场景下，前端可能不传 project_id；
        # lipsync 路径下 generation_task_id 也可能暂时为空。空串会被下面统一兜底为 "" 入库。
        if not name or not name.strip():
            raise ValueError("name cannot be empty")
        if not file_url or not file_url.strip():
            raise ValueError("file_url cannot be empty")
        return cls(
            id=uuid4().hex,
            project_id=(project_id or "").strip(),
            user_id=(user_id or "").strip(),
            generation_task_id=(generation_task_id or "").strip(),
            name=name.strip(),
            file_url=file_url.strip(),
            file_size=file_size,
            duration=duration,
            width=width,
            height=height,
            fps=fps,
            thumbnail_url=thumbnail_url,
            generation_params=generation_params or {},
        )