"""
gemini_client.py — API client menggunakan PuruBoy NoteGPT API (SSE streaming).
Endpoint: https://puruboy-api.vercel.app/api/ai/notegpt
Payload  : {"prompt": "<teks>"}

Format SSE:
  data: {"text": "..."}              → akumulasi teks
  data: {"text": "", "done": true}   → sinyal hampir selesai (mungkin ada teks terakhir)
  data: {"type": "finish"}           → akhir stream sesungguhnya
"""
from __future__ import annotations

import json
import time
import urllib.request
import urllib.error

GEMINI_API_URL = "https://puruboy-api.vercel.app/api/ai/notegpt"
DEFAULT_MODEL  = "notegpt"


class GeminiAPIError(Exception):
    pass


def _parse_sse_response(resp) -> str:
    """
    Baca SSE stream, akumulasi semua chunk text.

    Validasi:
      - Jika done/finish diterima tapi teks kosong → raise GeminiAPIError (trigger retry).
    """
    accumulated = []

    for raw_line in resp:
        line = raw_line.decode("utf-8", errors="replace").rstrip("\r\n")

        if not line.startswith("data:"):
            continue

        data_str = line[len("data:"):].strip()
        if not data_str:
            continue

        try:
            event = json.loads(data_str)
        except json.JSONDecodeError:
            continue

        # Akumulasi teks
        text_chunk = event.get("text", "")
        if text_chunk:
            accumulated.append(text_chunk)

        # Cek sinyal selesai
        is_done   = event.get("done", False)
        is_finish = event.get("type") == "finish"

        if is_done or is_finish:
            if not accumulated:
                raise GeminiAPIError(
                    "API mengirim sinyal selesai tapi tidak ada konten teks "
                    f"({'done=true' if is_done else 'type=finish'})"
                )
            if is_finish:
                break

    result = "".join(accumulated).strip()
    if not result:
        raise GeminiAPIError("Respons API kosong (tidak ada teks terakumulasi)")
    return result


def call_gemini(prompt: str, model: str = DEFAULT_MODEL) -> str:
    """
    Kirim prompt ke PuruBoy NoteGPT API (SSE) dengan Exponential Backoff.

    Retry jika:
      - Error jaringan / HTTP error
      - Respons kosong atau done/finish tanpa konten
    """
    payload     = json.dumps({"prompt": prompt}).encode("utf-8")
    max_retries = 5
    delay       = 4

    for attempt in range(max_retries):
        req = urllib.request.Request(
            GEMINI_API_URL,
            data=payload,
            headers={
                "Content-Type": "application/json",
                "User-Agent":   "GeminiClaw/3.0",
            },
            method="POST",
        )
        try:
            with urllib.request.urlopen(req, timeout=90) as resp:
                result = _parse_sse_response(resp)
            return result

        except GeminiAPIError as e:
            if attempt == max_retries - 1:
                raise GeminiAPIError(f"Gagal setelah {max_retries} percobaan: {e}")
            print(f"[Percobaan {attempt+1}] Gagal: {e}. Retry dalam {delay}s...")
            time.sleep(delay)
            delay = min(delay * 2, 60)

        except urllib.error.HTTPError as e:
            err_body = ""
            try:
                err_body = e.read().decode("utf-8", errors="replace")[:200]
            except Exception:
                pass
            msg = f"HTTP {e.code}: {err_body}"
            if attempt == max_retries - 1:
                raise GeminiAPIError(f"Gagal setelah {max_retries} percobaan: {msg}")
            print(f"[Percobaan {attempt+1}] {msg}. Retry dalam {delay}s...")
            time.sleep(delay)
            delay = min(delay * 2, 60)

        except urllib.error.URLError as e:
            msg = str(e.reason)
            if attempt == max_retries - 1:
                raise GeminiAPIError(f"Gagal setelah {max_retries} percobaan: {msg}")
            print(f"[Percobaan {attempt+1}] URLError: {msg}. Retry dalam {delay}s...")
            time.sleep(delay)
            delay = min(delay * 2, 60)