LabelingSystem/backend/routers/export.py

"""
Export API router.
Provides endpoints for exporting project annotations in various formats.
"""
import os
from fastapi import APIRouter, HTTPException, status, Request
from fastapi.responses import FileResponse
from database import get_db_connection
from schemas.export import (
    ExportRequest, ExportJobResponse, ExportProgressResponse,
    ExportFormat, ExportStatus
)
from services.export_service import ExportService

router = APIRouter(
    prefix="/api",
    tags=["export"]
)


@router.post("/projects/{project_id}/export", response_model=ExportJobResponse)
async def create_export(
    request: Request,
    project_id: str,
    export_request: ExportRequest
):
    """
    Create a new export job for a project.
    
    Args:
        request: FastAPI Request object (contains user info)
        project_id: Project unique identifier
        export_request: Export configuration
    
    Returns:
        Export job details
    
    Raises:
        HTTPException: 404 if project not found
        HTTPException: 403 if user doesn't have permission
        
    Requires authentication (admin only).
    """
    # Get current user
    user = request.state.user
    
    # Check admin permission
    if user["role"] != "admin":
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail="只有管理员可以导出数据"
        )
    
    # Verify project exists
    project = ExportService.get_project_data(project_id)
    if not project:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=f"项目 '{project_id}' 不存在"
        )
    
    # Create export job
    job_id = ExportService.create_export_job(
        project_id=project_id,
        format=export_request.format.value,
        status_filter=export_request.status_filter.value,
        include_metadata=export_request.include_metadata,
        created_by=user["id"]
    )
    
    # Execute export synchronously (for simplicity)
    # In production, this should be done asynchronously with a task queue
    result = ExportService.execute_export(
        job_id=job_id,
        project_id=project_id,
        format=export_request.format.value,
        status_filter=export_request.status_filter.value,
        include_metadata=export_request.include_metadata
    )
    
    # Get updated job info
    job = ExportService.get_export_job(job_id)
    
    if not job:
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail="导出任务创建失败"
        )
    
    # Build download URL if completed
    download_url = None
    if job["status"] == ExportStatus.COMPLETED.value and job["file_path"]:
        download_url = f"/api/exports/{job_id}/download"
    
    return ExportJobResponse(
        id=job["id"],
        project_id=job["project_id"],
        format=job["format"],
        status=job["status"],
        status_filter=job["status_filter"],
        include_metadata=job["include_metadata"],
        file_path=job["file_path"],
        download_url=download_url,
        error_message=job["error_message"],
        created_at=job["created_at"],
        completed_at=job["completed_at"],
        total_tasks=job["total_tasks"],
        exported_tasks=job["exported_tasks"]
    )


@router.get("/exports/{export_id}/status", response_model=ExportProgressResponse)
async def get_export_status(request: Request, export_id: str):
    """
    Get export job status and progress.
    
    Args:
        request: FastAPI Request object (contains user info)
        export_id: Export job unique identifier
    
    Returns:
        Export job progress details
    
    Raises:
        HTTPException: 404 if export job not found
        
    Requires authentication.
    """
    job = ExportService.get_export_job(export_id)
    
    if not job:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=f"导出任务 '{export_id}' 不存在"
        )
    
    # Calculate progress
    progress = 0.0
    if job["total_tasks"] > 0:
        progress = job["exported_tasks"] / job["total_tasks"]
    elif job["status"] == ExportStatus.COMPLETED.value:
        progress = 1.0
    
    return ExportProgressResponse(
        id=job["id"],
        status=job["status"],
        progress=progress,
        total_tasks=job["total_tasks"],
        exported_tasks=job["exported_tasks"],
        error_message=job["error_message"]
    )


@router.get("/exports/{export_id}/download")
async def download_export(request: Request, export_id: str):
    """
    Download exported file.
    
    Args:
        request: FastAPI Request object (contains user info)
        export_id: Export job unique identifier
    
    Returns:
        File download response
    
    Raises:
        HTTPException: 404 if export job or file not found
        HTTPException: 400 if export not completed
        
    Requires authentication.
    """
    job = ExportService.get_export_job(export_id)
    
    if not job:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=f"导出任务 '{export_id}' 不存在"
        )
    
    if job["status"] != ExportStatus.COMPLETED.value:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=f"导出任务尚未完成，当前状态: {job['status']}"
        )
    
    if not job["file_path"] or not os.path.exists(job["file_path"]):
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="导出文件不存在"
        )
    
    # Determine media type based on format
    media_type = "application/json"
    if job["format"] == ExportFormat.CSV.value:
        media_type = "text/csv"
    
    # Get filename from path
    filename = os.path.basename(job["file_path"])
    
    return FileResponse(
        path=job["file_path"],
        media_type=media_type,
        filename=filename
    )


@router.get("/exports/{export_id}", response_model=ExportJobResponse)
async def get_export_job(request: Request, export_id: str):
    """
    Get export job details.
    
    Args:
        request: FastAPI Request object (contains user info)
        export_id: Export job unique identifier
    
    Returns:
        Export job details
    
    Raises:
        HTTPException: 404 if export job not found
        
    Requires authentication.
    """
    job = ExportService.get_export_job(export_id)
    
    if not job:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail=f"导出任务 '{export_id}' 不存在"
        )
    
    # Build download URL if completed
    download_url = None
    if job["status"] == ExportStatus.COMPLETED.value and job["file_path"]:
        download_url = f"/api/exports/{job['id']}/download"
    
    return ExportJobResponse(
        id=job["id"],
        project_id=job["project_id"],
        format=job["format"],
        status=job["status"],
        status_filter=job["status_filter"],
        include_metadata=job["include_metadata"],
        file_path=job["file_path"],
        download_url=download_url,
        error_message=job["error_message"],
        created_at=job["created_at"],
        completed_at=job["completed_at"],
        total_tasks=job["total_tasks"],
        exported_tasks=job["exported_tasks"]
    )