"""Minimal OpenAI-compatible chat client, standalone (no third-party deps, no import of
lean_agent) so this pipeline works regardless of whether lean-agent is pip-installed.
Mirrors lean_agent.core.HTTPProvider on purpose; kept separate deliberately."""
import json
import os
import urllib.request


def load_dotenv(path):
    """Load KEY=VALUE lines from a .env file into os.environ (does not overwrite vars
    already set). Silently does nothing if the file does not exist."""
    if not path.exists():
        return
    for line in path.read_text(encoding='utf-8').splitlines():
        line = line.strip()
        if not line or line.startswith('#') or '=' not in line:
            continue
        key, _, value = line.partition('=')
        key = key.strip()
        value = value.strip().strip('"').strip("'")
        os.environ.setdefault(key, value)


class ChatClient:
    """OpenAI-compatible /chat/completions caller."""

    def __init__(self, model, base_url, api_key_env='DASHSCOPE_API_KEY', timeout=300):
        self.model = model
        self.base_url = base_url.rstrip('/')
        self.api_key_env = api_key_env
        self.timeout = timeout

    def complete(self, messages, temperature=0.2):
        key = os.environ.get(self.api_key_env)
        if not key:
            raise RuntimeError(f'Missing API key in environment variable {self.api_key_env}')
        headers = {"Content-Type": "application/json", "Authorization": "Bearer " + key}
        payload = {"model": self.model, "messages": messages, "temperature": temperature}
        request = urllib.request.Request(self.base_url + '/chat/completions',
                                          data=json.dumps(payload).encode(), headers=headers)
        with urllib.request.urlopen(request, timeout=self.timeout) as response:
            data = json.load(response)
        content = data["choices"][0]["message"]["content"]
        if not isinstance(content, str):
            raise ValueError("Provider returned non-text content")
        return content