#!/usr/bin/env python3
import http.server, json, sys, os, threading

PORT = int(sys.argv[1])
CONFIG = sys.argv[2]
REQ_FILE = sys.argv[3]

idx_lock = threading.Lock()
mode = 'SINGLE'
default_code = 200
responses = []
idx_path = ''

with open(CONFIG) as f:
    mode = f.readline().strip()
    if mode == 'SEQUENCE':
        seq_raw = f.readline().strip()
        idx_path = f.readline().strip()
        responses = json.loads(seq_raw)
    else:
        default_code = int(f.readline().strip())

def read_idx():
    try:
        with open(idx_path) as f2:
            return int(f2.read().strip())
    except:
        return 0

def write_idx(v):
    with open(idx_path, 'w') as f2:
        f2.write(str(v))

class H(http.server.BaseHTTPRequestHandler):
    def _get_response(self):
        if mode == 'SEQUENCE':
            with idx_lock:
                i = read_idx()
                r = responses[min(i, len(responses)-1)]
                write_idx(i + 1)
            code = r.get('code', 200)
            body = r.get('body', {'id':1})
            return code, json.dumps(body)
        return default_code, json.dumps({'id':1})

    def _log_request(self, method):
        path = self.path
        content_len = int(self.headers.get('Content-Length', 0))
        body = self.rfile.read(content_len).decode(errors='replace') if content_len else ''
        line = f'{method} {path}\n{body}\n'
        with open(REQ_FILE, 'a') as f:
            f.write(line)

    def do_GET(self):
        self._log_request('GET')
        code, body = self._get_response()
        self.send_response(code)
        self.send_header('Content-Type', 'application/json')
        self.end_headers()
        self.wfile.write(body.encode())

    def do_POST(self):
        self._log_request('POST')
        code, body = self._get_response()
        self.send_response(code)
        self.send_header('Content-Type', 'application/json')
        self.end_headers()
        self.wfile.write(body.encode())

    def do_PATCH(self):
        self._log_request('PATCH')
        code, body = self._get_response()
        self.send_response(code)
        self.send_header('Content-Type', 'application/json')
        self.end_headers()
        self.wfile.write(body.encode())

    def log_message(self, format, *args):
        pass

s = http.server.HTTPServer(('', PORT), H)
s.allow_reuse_address = True
s.serve_forever()