app/api/convert.py

"""
音频转换API路由
处理EPUB转音频的核心业务逻辑
"""

from fastapi import APIRouter, HTTPException
from pydantic import BaseModel, field_validator
from typing import List
from datetime import datetime
import re

from app.models.task import (
    ConversionTask,
    VoiceSettings as TaskVoiceSettings,
    TaskStatus,
)
from app.services.task_queue import task_queue
from app.core.logging import get_logger

logger = get_logger(__name__)
router = APIRouter()


class VoiceSettings(BaseModel):
    """语音设置模型"""

    language: str = "zh-CN"
    voice_name: str = "xiaoxiao"
    speed: float = 1.0
    pitch: int = 0
    volume: float = 0.8

    @field_validator("speed")
    @classmethod
    def validate_speed(cls, v):
        if not 0.5 <= v <= 2.0:
            raise ValueError("语速必须在0.5-2.0之间")
        return v

    @field_validator("pitch")
    @classmethod
    def validate_pitch(cls, v):
        if not -20 <= v <= 20:
            raise ValueError("音调必须在-20到20之间")
        return v


class ConvertRequest(BaseModel):
    """转换请求模型"""

    file_url: str
    voice_settings: VoiceSettings = VoiceSettings()
    output_formats: List[str] = ["mp3"]
    audio_quality: str = "high"
    split_by_chapter: bool = True
    max_segment_length: int = 300

    @field_validator("file_url")
    @classmethod
    def validate_file_url(cls, v):
        if not v or not v.startswith(("http://", "https://")):
            raise ValueError("文件URL格式无效")
        if not v.lower().endswith((".epub", ".txt")):
            raise ValueError("仅支持EPUB和TXT格式文件")
        return v

    @field_validator("output_formats")
    @classmethod
    def validate_output_formats(cls, v):
        supported_formats = ["mp3", "wav", "m4a"]
        for fmt in v:
            if fmt not in supported_formats:
                raise ValueError(f"不支持的输出格式: {fmt}")
        return v


class ConvertR2Request(BaseModel):
    """R2路径转换请求模型"""

    r2_file_path: str
    voice_settings: VoiceSettings = VoiceSettings()
    output_formats: List[str] = ["mp3"]
    audio_quality: str = "high"
    split_by_chapter: bool = True
    max_segment_length: int = 300

    @field_validator("r2_file_path")
    @classmethod
    def validate_r2_file_path(cls, v):
        if not v or not v.strip():
            raise ValueError("R2文件路径不能为空")

        # 清理路径
        v = v.strip()

        # 验证路径格式：users/{user_id}/{category}/{task_id}/{filename}
        path_parts = v.split('/')
        if len(path_parts) < 4:
            raise ValueError("R2文件路径格式无效，应为: users/{user_id}/{category}/{task_id}/{filename}")

        if path_parts[0] != "users":
            raise ValueError("R2文件路径必须以'users/'开头")

        # 验证各部分不能为空
        for i, part in enumerate(path_parts):
            if not part.strip():
                raise ValueError(f"路径第{i+1}部分不能为空")

        # 验证文件扩展名
        filename = path_parts[-1]
        if not filename.lower().endswith((".epub", ".txt")):
            raise ValueError("仅支持EPUB和TXT格式文件")

        return v

    @field_validator("output_formats")
    @classmethod
    def validate_output_formats(cls, v):
        supported_formats = ["mp3", "wav", "m4a"]
        for fmt in v:
            if fmt not in supported_formats:
                raise ValueError(f"不支持的输出格式: {fmt}")
        return v


class ConvertResponse(BaseModel):
    """转换响应模型"""

    task_id: str
    status: str
    message: str
    queue_position: int
    estimated_time: str
    queue_size: int


@router.post("/convert", response_model=ConvertResponse)
async def submit_conversion_task(request: ConvertRequest):
    """提交EPUB转音频任务"""
    try:
        logger.info(f"收到转换请求: {request.file_url}")

        # 创建转换任务
        task = ConversionTask(
            file_url=request.file_url,
            voice_settings=TaskVoiceSettings(
                language=request.voice_settings.language,
                voice_name=request.voice_settings.voice_name,
                speed=request.voice_settings.speed,
                pitch=request.voice_settings.pitch,
                volume=request.voice_settings.volume,
            ),
            output_formats=request.output_formats,
            audio_quality=request.audio_quality,
            split_by_chapter=request.split_by_chapter,
            max_segment_length=request.max_segment_length,
        )

        # 提取原始文件名
        import os

        task.original_filename = os.path.basename(request.file_url)

        # 添加到任务队列
        success = task_queue.add_task(task)

        if not success:
            raise HTTPException(
                status_code=503,
                detail={
                    "error": {
                        "code": "QUEUE_FULL",
                        "message": "任务队列已满，请稍后重试",
                        "timestamp": datetime.now().isoformat(),
                    }
                },
            )

        # 获取队列状态
        queue_status = task_queue.get_queue_status()

        return ConvertResponse(
            task_id=task.task_id,
            status=task.status.value,
            message="音频转换任务已添加到队列",
            queue_position=task.queue_position,
            estimated_time="15分钟",  # TODO: 基于队列状态计算
            queue_size=queue_status["queue_size"],
        )

    except ValueError as e:
        raise HTTPException(
            status_code=400,
            detail={
                "error": {
                    "code": "INVALID_REQUEST",
                    "message": str(e),
                    "timestamp": datetime.now().isoformat(),
                }
            },
        )
    except Exception as e:
        logger.error(f"提交转换任务失败: {str(e)}")
        raise HTTPException(
            status_code=500,
            detail={
                "error": {
                    "code": "INTERNAL_SERVER_ERROR",
                    "message": "服务器内部错误",
                    "timestamp": datetime.now().isoformat(),
                }
            },
        )


@router.post("/convert-r2", response_model=ConvertResponse)
async def submit_conversion_task_r2(request: ConvertR2Request):
    """提交R2路径EPUB转音频任务"""
    try:
        logger.info(f"收到R2路径转换请求: {request.r2_file_path}")

        # 对于R2路径，直接使用r2://前缀，让存储服务处理下载逻辑
        # 这样可以避免构建可能不正确的HTTP URL
        file_url = f"r2://{request.r2_file_path}"

        # 创建转换任务
        task = ConversionTask(
            file_url=file_url,
            voice_settings=TaskVoiceSettings(
                language=request.voice_settings.language,
                voice_name=request.voice_settings.voice_name,
                speed=request.voice_settings.speed,
                pitch=request.voice_settings.pitch,
                volume=request.voice_settings.volume,
            ),
            output_formats=request.output_formats,
            audio_quality=request.audio_quality,
            split_by_chapter=request.split_by_chapter,
            max_segment_length=request.max_segment_length,
        )

        # 设置R2路径信息
        task.r2_file_path = request.r2_file_path

        # 提取原始文件名
        import os
        task.original_filename = os.path.basename(request.r2_file_path)

        # 添加到任务队列
        success = task_queue.add_task(task)

        if not success:
            raise HTTPException(
                status_code=503,
                detail={
                    "error": {
                        "code": "QUEUE_FULL",
                        "message": "任务队列已满，请稍后重试",
                        "timestamp": datetime.now().isoformat(),
                    }
                },
            )

        # 获取队列状态
        queue_status = task_queue.get_queue_status()

        return ConvertResponse(
            task_id=task.task_id,
            status=task.status.value,
            message="R2路径音频转换任务已添加到队列",
            queue_position=task.queue_position,
            estimated_time="15分钟",  # TODO: 基于队列状态计算
            queue_size=queue_status["queue_size"],
        )

    except ValueError as e:
        raise HTTPException(
            status_code=400,
            detail={
                "error": {
                    "code": "INVALID_REQUEST",
                    "message": str(e),
                    "timestamp": datetime.now().isoformat(),
                }
            },
        )
    except Exception as e:
        logger.error(f"提交R2路径转换任务失败: {str(e)}")
        raise HTTPException(
            status_code=500,
            detail={
                "error": {
                    "code": "INTERNAL_SERVER_ERROR",
                    "message": "服务器内部错误",
                    "timestamp": datetime.now().isoformat(),
                }
            },
        )


@router.get("/convert/{task_id}/status")
async def get_conversion_status(task_id: str):
    """查询转换任务状态（兼容旧版本）"""
    try:
        # 验证任务ID格式
        if not re.match(r"^audio_[0-9a-f-]+$", task_id):
            raise HTTPException(
                status_code=400,
                detail={
                    "error": {
                        "code": "INVALID_TASK_ID",
                        "message": "任务ID格式无效",
                        "timestamp": datetime.now().isoformat(),
                    }
                },
            )

        # 获取任务信息
        task = task_queue.get_task(task_id)

        if not task:
            raise HTTPException(
                status_code=404,
                detail={
                    "error": {
                        "code": "TASK_NOT_FOUND",
                        "message": "任务不存在",
                        "timestamp": datetime.now().isoformat(),
                    }
                },
            )

        return task.to_dict()

    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"查询任务状态失败: {str(e)}")
        raise HTTPException(
            status_code=500,
            detail={
                "error": {
                    "code": "INTERNAL_SERVER_ERROR",
                    "message": "服务器内部错误",
                    "timestamp": datetime.now().isoformat(),
                }
            },
        )


@router.get("/convert/{user_id}/{task_id}/status")
async def get_conversion_status_with_user(user_id: str, task_id: str):
    """查询转换任务状态（新版本，支持从R2读取）"""
    try:
        # 验证参数格式
        if not user_id or not task_id:
            raise HTTPException(
                status_code=400,
                detail={
                    "error": {
                        "code": "INVALID_PARAMETERS",
                        "message": "用户ID和任务ID不能为空",
                        "timestamp": datetime.now().isoformat(),
                    }
                },
            )

        # 获取任务信息（优先从R2读取）
        task = await task_queue.get_task_with_user_id(user_id, task_id)

        if not task:
            raise HTTPException(
                status_code=404,
                detail={
                    "error": {
                        "code": "TASK_NOT_FOUND",
                        "message": "任务不存在",
                        "timestamp": datetime.now().isoformat(),
                    }
                },
            )

        return task.to_dict()

    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"查询任务状态失败: {str(e)}")
        raise HTTPException(
            status_code=500,
            detail={
                "error": {
                    "code": "INTERNAL_SERVER_ERROR",
                    "message": "服务器内部错误",
                    "timestamp": datetime.now().isoformat(),
                }
            },
        )


@router.get("/convert/{task_id}/result")
async def get_conversion_result(task_id: str):
    """获取转换结果"""
    try:
        # 验证任务ID格式
        if not re.match(r"^audio_[0-9a-f-]+$", task_id):
            raise HTTPException(
                status_code=400,
                detail={
                    "error": {
                        "code": "INVALID_TASK_ID",
                        "message": "任务ID格式无效",
                        "timestamp": datetime.now().isoformat(),
                    }
                },
            )

        # 获取任务信息
        task = task_queue.get_task(task_id)

        if not task:
            raise HTTPException(
                status_code=404,
                detail={
                    "error": {
                        "code": "TASK_NOT_FOUND",
                        "message": "任务不存在",
                        "timestamp": datetime.now().isoformat(),
                    }
                },
            )

        # 检查任务状态
        if task.status != TaskStatus.COMPLETED:
            raise HTTPException(
                status_code=400,
                detail={
                    "error": {
                        "code": "TASK_NOT_COMPLETED",
                        "message": f"任务尚未完成，当前状态: {task.status.value}",
                        "timestamp": datetime.now().isoformat(),
                    }
                },
            )

        # 返回完整的任务结果
        result = task.to_dict()
        result.update(
            {
                "original_filename": task.original_filename,
                "audio_files": task.audio_files,
                "metadata": task.metadata,
            }
        )

        return result

    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"获取转换结果失败: {str(e)}")
        raise HTTPException(
            status_code=500,
            detail={
                "error": {
                    "code": "INTERNAL_SERVER_ERROR",
                    "message": "服务器内部错误",
                    "timestamp": datetime.now().isoformat(),
                }
            },
        )