"""
Reports API endpoints.

Provides endpoints for:
- GET /api/reports - Get paginated list of reports
- GET /api/reports/detail - Get report details
- GET /api/reports/download - Download report file
- POST /api/reports/delete - Delete a report
"""

import os
from flask import jsonify, request, send_file, current_app
from app.api import api_bp
from app.services import login_required, get_current_user_from_context, get_accessible_reports
from app.services.report_service import ReportService
from app.models import Report, Task


@api_bp.route('/reports', methods=['GET'])
@login_required
def get_reports():
    """
    Get paginated list of reports.
    
    Query Parameters:
        page: Page number (default: 1)
        page_size: Items per page (default: 20, max: 100)
        task_id: Optional filter by task ID
    
    Returns:
        JSON with 'data' array and 'pagination' object
    """
    current_user = get_current_user_from_context()
    
    page = request.args.get('page', 1, type=int)
    # Support both pageSize (frontend) and page_size (backend convention)
    page_size = request.args.get('pageSize', type=int) or request.args.get('page_size', type=int) or 20
    page_size = min(page_size, 100)
    task_id = request.args.get('task_id', type=int)
    
    # For regular users, only show their own reports
    user_id = None
    if current_user.role == 'user':
        user_id = current_user.id
    
    result = ReportService.get_reports(
        page=page,
        page_size=page_size,
        task_id=task_id,
        user_id=user_id
    )
    
    return jsonify(result), 200


@api_bp.route('/reports/detail', methods=['GET'])
@login_required
def get_report_detail():
    """
    Get report details.
    
    Query Parameters:
        id: Report ID (required)
    
    Returns:
        JSON with report details
    """
    current_user = get_current_user_from_context()
    report_id = request.args.get('id', type=int)
    
    if not report_id:
        return jsonify({'error': {'code': 'MISSING_PARAMETER', 'message': 'Report ID is required'}}), 400
    
    report = ReportService.get_report_by_id(report_id)
    if not report:
        return jsonify({'error': {'code': 'NOT_FOUND', 'message': 'Report not found'}}), 404
    
    # Check access for regular users
    if current_user.role == 'user':
        task = Task.query.get(report.task_id)
        if not task or task.created_by != current_user.id:
            return jsonify({'error': {'code': 'FORBIDDEN', 'message': 'Access denied'}}), 403
    
    return jsonify(report.to_dict()), 200



@api_bp.route('/reports/download', methods=['GET'])
@login_required
def download_report():
    """
    Download a report file.
    
    Query Parameters:
        id: Report ID (required)
    
    Returns:
        The report file as attachment
    """
    current_user = get_current_user_from_context()
    report_id = request.args.get('id', type=int)
    
    if not report_id:
        return jsonify({'error': {'code': 'MISSING_PARAMETER', 'message': 'Report ID is required'}}), 400
    
    report = ReportService.get_report_by_id(report_id)
    if not report:
        return jsonify({'error': {'code': 'NOT_FOUND', 'message': 'Report not found'}}), 404
    
    # Check access for regular users
    if current_user.role == 'user':
        task = Task.query.get(report.task_id)
        if not task or task.created_by != current_user.id:
            return jsonify({'error': {'code': 'FORBIDDEN', 'message': 'Access denied'}}), 403
    
    # Get file path
    file_path = ReportService.get_report_file_path(report_id)
    if not file_path:
        return jsonify({'error': {'code': 'FILE_NOT_FOUND', 'message': 'Report file not found'}}), 404
    
    return send_file(
        file_path,
        as_attachment=True,
        download_name=report.file_name,
        mimetype='application/vnd.openxmlformats-officedocument.wordprocessingml.document'
    )


@api_bp.route('/reports/delete', methods=['POST'])
@login_required
def delete_report():
    """
    Delete a report.
    
    Request Body:
        id: Report ID (required)
    
    Returns:
        JSON with success message
    """
    current_user = get_current_user_from_context()
    data = request.get_json() or {}
    report_id = data.get('id')
    
    if not report_id:
        return jsonify({'error': {'code': 'MISSING_PARAMETER', 'message': 'Report ID is required'}}), 400
    
    report = ReportService.get_report_by_id(report_id)
    if not report:
        return jsonify({'error': {'code': 'NOT_FOUND', 'message': 'Report not found'}}), 404
    
    # Only admins can delete reports, or users can delete their own
    if current_user.role == 'user':
        task = Task.query.get(report.task_id)
        if not task or task.created_by != current_user.id:
            return jsonify({'error': {'code': 'FORBIDDEN', 'message': 'Access denied'}}), 403
    
    success = ReportService.delete_report(report_id)
    if success:
        return jsonify({'message': 'Report deleted successfully'}), 200
    else:
        return jsonify({'error': {'code': 'DELETE_FAILED', 'message': 'Failed to delete report'}}), 500