from http.server import HTTPServer, BaseHTTPRequestHandler
from urllib.parse import parse_qs
import re

import MySQLdb

from config import *


def render_template(path, **kwargs):
    with open(path) as f:
        template = f.read()

    for key in kwargs:
        template = template.replace(f'%%{key}%%', kwargs[key])

    return template


def parse_query(query):
    parsed_query = {'expression': {}, 'condition': {}}

    pattern = re.compile(r'(expression|condition)(\d+)_(key|value)')

    for key, (value,) in query.items():
        match = pattern.fullmatch(key)
        if match is not None:
            index = int(match.group(2))
            if index not in parsed_query[match.group(1)]:
                parsed_query[match.group(1)][index] = {}

            parsed_query[match.group(1)][index][match.group(3)] = value

    expressions = []
    for expression in parsed_query['expression'].values():
        expressions.append('`{}`="{}"'.format(
            expression['key'], expression['value']
        ))
    expressions = ','.join(expressions)

    conditions = []
    for condition in parsed_query['condition'].values():
        conditions.append('`{}`="{}"'.format(
            condition['key'], condition['value']
        ))
    conditions = ','.join(conditions)

    return {'expressions': expressions, 'conditions': conditions}


class MyHTTPRequestHandler(BaseHTTPRequestHandler):
    def update_post(self, query):
        expressions, conditions = parse_query(query)

        cursor = db.cursor()
        cursor.execute('UPDATE `table_task1` SET {} WHERE {}'.format(
            expressions, conditions
        ))
        result = cursor.fetchall()
        cursor.close()

        return f'<h1>UPDATE: {result}</h1>'

    def delete_post(self, query):
        return f'<h1>DELETE: {query}</h1>'

    def add_post(self, query):
        return f'<h1>ADD: {query}</h1>'

    def index_get(self):
        cursor = db.cursor()
        cursor.execute('DESCRIBE table_task1;')
        table_structure = cursor.fetchall()

        cursor.execute('SELECT * FROM table_task1;')
        content = cursor.fetchall()

        cursor.close()

        heading = []
        for column in [field[0] for field in table_structure]:
            heading.append(f'<th>{column}</th>')
        heading = '<thead><tr>\n%s\n</tr></thead>' % '\n'.join(heading)

        rows = []
        for row_index, row in enumerate(content):
            formatted = []
            for field_index, field in enumerate(row):
                color = 'odd' if (field_index % 2 + row_index % 2) % 2 == 0 else 'even'

                formatted.append(f'<td class={color}>{field}</td>')

            rows.append('<tr>{}</tr>'.format(''.join(formatted)))

        body = '<tbody>{}</tbody>'.format("\n".join(rows))

        data = render_template('index.html', heading=heading, body=body)

        return data

    def _set_response(self):
        self.send_response(200)
        self.send_header('Content-type', 'text/html')
        self.end_headers()

    def do_GET(self):
        if self.path == '/':
            response = self.index_get()
        else:
            response = '<center><h1>ERROR 404 NOT FOUND</h1></center>'

        self._set_response()
        self.wfile.write(response.encode('utf-8'))

    def do_POST(self):
        content_length = int(self.headers['Content-Length'])
        post_data = parse_qs(self.rfile.read(content_length).decode('utf-8'))

        if self.path == '/update':
            response = self.update_post(post_data)

        elif self.path == '/delete':
            response = self.delete_post(post_data)

        elif self.path == '/add':
            response = self.add_post(post_data)

        else:
            response = '<center><h1>ERROR 404 NOT FOUND</h1></center>'

        self._set_response()
        self.wfile.write(response.encode('utf-8'))


# В файле config.py создайте соответствующие переменные
db = MySQLdb.connect(
    host=HOST,
    user=USERNAME,
    passwd=PASSWORD,
    db=DATABASE_NAME
)

db.cursor().execute(
    '''
    CREATE TABLE IF NOT EXISTS `table_task1` (
      `service_id` int(11) NOT NULL AUTO_INCREMENT,
      `servtype` varchar(20) NOT NULL DEFAULT 'hosting',
      `subtype` varchar(32) NOT NULL DEFAULT '',
      `user_id` bigint(20) NOT NULL,
      `referrer_user_id` bigint(20) NOT NULL,
      `state` varchar(1) NOT NULL DEFAULT 'N',
      `creation_date` date NOT NULL DEFAULT '0000-01-01',
      `creation_time` time NOT NULL DEFAULT '00:00:00',
      `creation_request_sent_date` datetime DEFAULT NULL,
      `notified_about_expiration` smallint(6) NOT NULL DEFAULT '0',
      PRIMARY KEY (`service_id`)
    ) ENGINE=InnoDB AUTO_INCREMENT=35109400 DEFAULT CHARSET=utf8;
    '''
)

server_address = ("", 8000)
httpd = HTTPServer(server_address, MyHTTPRequestHandler)
httpd.serve_forever()