#!/usr/bin/env python3
import json
import os
import sys
from http.server import BaseHTTPRequestHandler, HTTPServer
from urllib.parse import urlparse


MODE = sys.argv[1] if len(sys.argv) > 1 else "alert"
PORT = int(os.environ.get("CASAN_MOCK_PORT", "8080"))
EVENTS = []


USAGE = [
    {
        "provider": "local-prod-mock",
        "model": "billing-api-emulator",
        "run_id": "infra-lab-run",
        "step": "speckit.implement",
        "input_tokens": 1842,
        "output_tokens": 936,
        "total_tokens": 2778,
        "cost_usd": 0.08334,
        "latency_ms": 4210,
        "status": "success",
    }
]


class Handler(BaseHTTPRequestHandler):
    def send_json(self, code, payload):
        body = json.dumps(payload).encode()
        self.send_response(code)
        self.send_header("Content-Type", "application/json")
        self.send_header("Content-Length", str(len(body)))
        self.end_headers()
        self.wfile.write(body)

    def do_GET(self):  # noqa: N802
        path = urlparse(self.path).path
        if path == "/healthz":
            self.send_json(200, {"status": "ok", "mode": MODE, "events": len(EVENTS)})
        elif MODE == "alert" and path == "/events":
            self.send_json(200, EVENTS)
        elif MODE == "billing" and path in ("/usage", "/v1/usage"):
            self.send_json(200, USAGE)
        else:
            self.send_json(404, {"error": "not_found"})

    def do_POST(self):  # noqa: N802
        if MODE != "alert":
            self.send_json(404, {"error": "not_found"})
            return
        size = int(self.headers.get("Content-Length", "0"))
        raw = self.rfile.read(size)
        try:
            payload = json.loads(raw or b"{}")
        except json.JSONDecodeError:
            payload = {"raw": raw.decode(errors="replace")}
        EVENTS.append(payload)
        self.send_json(200, {"ok": True, "events": len(EVENTS)})

    def log_message(self, *args):
        pass


if __name__ == "__main__":
    HTTPServer(("0.0.0.0", PORT), Handler).serve_forever()