import os

import requests
from fastapi import FastAPI, HTTPException, status
from openai import OpenAI
from pydantic import BaseModel

allowed_host_env = os.getenv("LLM_REVIEW_ALLOWED_HOST")
allowed_hosts = []
allowed_hosts_not_empty = True

if allowed_host_env is None:
    allowed_hosts_not_empty = False
else:
    allowed_hosts = allowed_host_env.split(',')
    if len(allowed_hosts) == 0:
        allowed_hosts_not_empty = False

for (i, host) in enumerate(allowed_hosts):
    allowed_hosts[i] = host.rstrip('/')

print(f'allowed host: {allowed_hosts}')

app = FastAPI()

class ReviewRequest(BaseModel):
    gitea_token: str
    gitea_host: str
    openrouter_key: str
    model: str
    repo: str
    pr_number: int

@app.get("/health")
def test():
    try:
        r = requests.get("https://openrouter.ai/api/v1/models")
        r.raise_for_status()
        return {"status": "ok"}
    except requests.exceptions.RequestException as e:
        raise HTTPException(
            status_code=status.HTTP_503_SERVICE_UNAVAILABLE,
            detail=f"OpenRouter health check failed: {e}",
        )

@app.post("/")
def review(
    request_body: ReviewRequest,
):
    gitea_host = request_body.gitea_host.rstrip("/")

    if allowed_hosts_not_empty and gitea_host not in allowed_hosts:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Request source is not allowed host",
        )

    headers = {"Authorization": f"token {request_body.gitea_token}"}

    diff_res = requests.get(f"{gitea_host}/api/v1/repos/{request_body.repo}/pulls/{request_body.pr_number}.diff", headers=headers)
    if diff_res.status_code != 200 or not diff_res.text.strip():
        return

    diff_text = diff_res.text

    client = OpenAI(base_url="https://openrouter.ai/api/v1", api_key=request_body.openrouter_key)

    prompt = (
            "You are an automated senior code reviewer. Review the following git diff.\n"
            "Focus on: critical bugs, security vulnerabilities, edge cases, and code smells.\n"
            "Keep it short and clear, don't give me long solutions.\n"
            "Dont point out good things only problems, errors, etc.\n"
            "Format your answer cleanly in Markdown with actionable feedback.\n\n"
            f"```diff\n{diff_text}\n```"
    )
    completion = client.chat.completions.create(
        model=request_body.model,
        messages=[{"role": "user", "content": prompt}]
    )

    review_content = completion.choices[0].message.content

    review_body = f"# llm review\n\n{review_content}"

    requests.post(
        f"{gitea_host}/api/v1/repos/{request_body.repo}/pulls/{request_body.pr_number}/reviews",
        headers=headers,
        json={"body": review_body, "event": "COMMENT"}
    )

    return {"status": "done"}