"""
app/api/photos.py
-----------------
Mobile API endpoint for uploading photos from the iPad app.

POST /api/v1/photos/upload
    Accepts a multipart/form-data upload.
    Saves the file to the server's upload folder.
    Returns the relative server path used in subsequent inspection/issue submissions.

The iPad app uploads photos BEFORE submitting the inspection or issue,
then includes the returned server_path in the inspection/issue payload.
"""

import os
import uuid
import logging

from flask import Blueprint, request, g, current_app
from app.api.errors import api_ok, api_error
from app.api.decorators import jwt_required

logger = logging.getLogger(__name__)

bp = Blueprint('api_photos', __name__)

_ALLOWED_EXTENSIONS = {'jpg', 'jpeg', 'png', 'gif'}
_ALLOWED_ROLES      = {'admin', 'director', 'inspector', 'project_manager', 'auditor'}


def _allowed_file(filename: str) -> bool:
    return (
        '.' in filename
        and filename.rsplit('.', 1)[-1].lower() in _ALLOWED_EXTENSIONS
    )


# ── Upload Photo ──────────────────────────────────────────────────────────────

@bp.route('/photos/upload', methods=['POST'])
@jwt_required
def upload_photo():
    """
    Upload a photo from the iPad app.

    Multipart form fields
    ---------------------
    file        — binary image data (jpg / png / gif)
    entity_type — "inspection" | "issue" | "issue_result"  (controls subfolder)

    Response 200
    ------------
    {
        "ok": true,
        "data": {
            "server_path": "uploads/inspection_photos/abc123.jpg"
        }
    }
    """
    user = g.api_user

    if user.role not in _ALLOWED_ROLES:
        return api_error('Access denied', 403)

    if 'file' not in request.files:
        return api_error('No file provided', 400)

    file_obj    = request.files['file']
    entity_type = request.form.get('entity_type', 'inspection')

    if not file_obj or not file_obj.filename:
        return api_error('Empty file', 400)

    if not _allowed_file(file_obj.filename):
        return api_error(
            f'File type not allowed. Accepted: {", ".join(sorted(_ALLOWED_EXTENSIONS))}',
            400
        )

    # Determine destination subfolder
    if entity_type == 'issue':
        subfolder = 'issue_photos'
    elif entity_type == 'issue_result':
        subfolder = 'issue_result_photos'
    else:
        subfolder = 'inspection_photos'

    ext      = file_obj.filename.rsplit('.', 1)[-1].lower()
    filename = f'{uuid.uuid4().hex}.{ext}'

    dest_dir = os.path.join(current_app.config['UPLOAD_FOLDER'], subfolder)
    os.makedirs(dest_dir, exist_ok=True)

    dest_path = os.path.join(dest_dir, filename)
    file_obj.save(dest_path)

    server_path = f'uploads/{subfolder}/{filename}'

    logger.info('API PHOTOS | uploaded | entity_type=%s | path=%s | user=%s',
                entity_type, server_path, user.username)

    return api_ok({'server_path': server_path})