"""
文件管理 Schema

文件上传/下载相关的请求/响应模型
"""

from datetime import datetime
from typing import List, Literal, Optional
from pydantic import BaseModel, Field


class FileMetadata(BaseModel):
    """
    文件元数据
    
    描述已上传文件的详细信息
    """
    id: str = Field(..., description="文件唯一标识")
    filename: str = Field(..., description="原始文件名")
    content_type: Optional[str] = Field(
        default=None,
        description="MIME 类型，如 'audio/wav', 'audio/mp3'"
    )
    size_bytes: int = Field(
        default=0,
        ge=0,
        description="文件大小（字节）"
    )
    purpose: Optional[Literal["training", "reference", "output"]] = Field(
        default="training",
        description="文件用途：training(训练), reference(参考音频), output(输出模型)"
    )
    duration_seconds: Optional[float] = Field(
        default=None,
        ge=0,
        description="音频时长（秒），仅音频文件有效"
    )
    sample_rate: Optional[int] = Field(
        default=None,
        ge=0,
        description="采样率（Hz），仅音频文件有效"
    )
    uploaded_at: datetime = Field(..., description="上传时间")
    
    model_config = {
        "json_schema_extra": {
            "examples": [
                {
                    "id": "550e8400-e29b-41d4-a716-446655440000",
                    "filename": "my_voice.wav",
                    "content_type": "audio/wav",
                    "size_bytes": 15728640,
                    "purpose": "training",
                    "duration_seconds": 120.5,
                    "sample_rate": 44100,
                    "uploaded_at": "2024-01-01T10:00:00Z"
                }
            ]
        }
    }


class FileUploadResponse(BaseModel):
    """
    文件上传响应
    
    上传成功后返回文件信息
    """
    success: bool = Field(default=True, description="是否成功")
    message: str = Field(default="文件上传成功", description="响应消息")
    file: FileMetadata = Field(..., description="文件元数据")
    
    model_config = {
        "json_schema_extra": {
            "examples": [
                {
                    "success": True,
                    "message": "文件上传成功",
                    "file": {
                        "id": "550e8400-e29b-41d4-a716-446655440000",
                        "filename": "my_voice.wav",
                        "content_type": "audio/wav",
                        "size_bytes": 15728640,
                        "purpose": "training",
                        "uploaded_at": "2024-01-01T10:00:00Z"
                    }
                }
            ]
        }
    }


class FileListResponse(BaseModel):
    """
    文件列表响应
    """
    items: List[FileMetadata] = Field(
        default_factory=list,
        description="文件列表"
    )
    total: int = Field(
        default=0,
        ge=0,
        description="总数量"
    )
    limit: int = Field(
        default=50,
        ge=1,
        le=100,
        description="每页数量"
    )
    offset: int = Field(
        default=0,
        ge=0,
        description="偏移量"
    )
    
    model_config = {
        "json_schema_extra": {
            "examples": [
                {
                    "items": [
                        {
                            "id": "file-123",
                            "filename": "voice_1.wav",
                            "content_type": "audio/wav",
                            "size_bytes": 5242880,
                            "purpose": "training",
                            "uploaded_at": "2024-01-01T10:00:00Z"
                        }
                    ],
                    "total": 1,
                    "limit": 50,
                    "offset": 0
                }
            ]
        }
    }


class FileDeleteResponse(BaseModel):
    """
    文件删除响应
    """
    success: bool = Field(default=True, description="是否成功")
    message: str = Field(default="文件删除成功", description="响应消息")
    file_id: str = Field(..., description="已删除的文件 ID")
    
    model_config = {
        "json_schema_extra": {
            "examples": [
                {
                    "success": True,
                    "message": "文件删除成功",
                    "file_id": "550e8400-e29b-41d4-a716-446655440000"
                }
            ]
        }
    }