import http.server
import logging
import os
import sqlite3
import tempfile

import db
import templates
import utils

logger = logging.getLogger(__name__)
conn = sqlite3.connect('db.sqlite3')
files_directory = 'download'
authorized_key = os.environ['KEY']

class MyServer(http.server.BaseHTTPRequestHandler):
    def do_GET(self):
        match self.path:
            case '/':
                self._serve_str(templates.index, 200, 'text/html')
            case '/main.js':
                self._serve_file('public/main.js', 'application/javascript')
            case '/main.css':
                self._serve_file('public/main.css', 'text/css')
            case path:
                prefix = f'/{files_directory}/'
                if path.startswith(prefix):
                    file_id = path[len(prefix):]
                    res = db.get_file(conn, file_id)
                    if res is None:
                        self._serve_str(templates.not_found, 404, 'text/html')
                    else:
                        filename, _, content_length = res
                        path = os.path.join(files_directory, file_id)
                        headers = [
                            ('Content-Disposition', f'attachment; filename={filename}'),
                            ('Content-Length', content_length)
                        ]
                        self._serve_file(path, 'application/octet-stream', headers)
                else:
                    file_id = path[1:]
                    res = db.get_file(conn, file_id)
                    if res is None:
                        self._serve_str(templates.not_found, 404, 'text/html')
                    else:
                        filename, expires, _ = res
                        href = os.path.join(files_directory, file_id)
                        self._serve_str(templates.download(href, filename, expires), 200, 'text/html')

    def do_POST(self):
        key = self.headers['X-Key']
        if not key == authorized_key:
            logging.info('Unauthorized to upload file: wrong key')
            self._serve_str('Unauthorized', 401)

        else:
            logging.info('Uploading file')
            content_length = int(self.headers['content-length'])
            filename = utils.sanitize_filename(self.headers['X-FileName'])
            expiration = self.headers['X-Expiration']

            with tempfile.NamedTemporaryFile(delete = False) as tmp:
              utils.transfer(self.rfile, tmp, content_length = content_length)

            logging.info('File uploaded')
            file_id = db.insert_file(conn, filename, expiration, content_length)
            os.makedirs(files_directory, exist_ok=True)
            os.rename(tmp.name, os.path.join(files_directory, file_id))

            self._serve_str(file_id, 200)

    def _serve_str(self, s, code, content_type='text/plain'):
        self.send_response(code)
        self.send_header('Content-type', content_type)
        self.end_headers()
        self.wfile.write(bytes(s, 'utf-8'))

    def _serve_file(self, filename, content_type, headers = []):
        self.send_response(200)
        self.send_header('Content-type', content_type)
        for header_name, header_value in headers:
            self.send_header(header_name, header_value)
        self.end_headers()
        with open(filename, 'rb') as f:
            utils.transfer(f, self.wfile)