"""
Human+ AI Client
Singleton Gemini client dengan typed config & error handling terpusat.
"""

import os
import streamlit as st
from google import genai
from google.genai import types

# ── Model config ─────────────────────────────────────────────────────
MODEL_NAME        = "gemini-2.5-flash-lite"
TEMP_EXTRACTION   = 0.1    # PDF extraction — deterministik
TEMP_PROTOCOL     = 0.4    # Protocol generation — sedikit kreatif

# PENTING: 4096 terlalu kecil untuk protocol lengkap (bisa 6000-10000 token).
# Naikkan ke 16000 agar semua section tidak terpotong.
MAX_TOKENS_EXTRACT  = 10000
MAX_TOKENS_PROTOCOL = 65536


class GeminiClientError(Exception):
    pass


@st.cache_resource(show_spinner=False)
def get_client() -> genai.Client:
    api_key = os.getenv("GEMINI_API_KEY")
    if not api_key:
        raise GeminiClientError(
            "GEMINI_API_KEY tidak ditemukan. "
            "Tambahkan di HuggingFace Settings → Repository Secrets."
        )
    try:
        return genai.Client(api_key=api_key)
    except Exception as e:
        raise GeminiClientError(f"Gagal menginisialisasi Gemini client: {e}") from e


def call_gemini(
    contents: list,
    temperature: float = TEMP_EXTRACTION,
    max_tokens: int = MAX_TOKENS_EXTRACT,
) -> str:
    try:
        client = get_client()
        response = client.models.generate_content(
            model=MODEL_NAME,
            contents=contents,
            config=types.GenerateContentConfig(
                temperature=temperature,
                max_output_tokens=max_tokens,
            ),
        )
        return response.text
    except GeminiClientError:
        raise
    except Exception as e:
        raise GeminiClientError(f"Gemini API call gagal: {e}") from e


def pdf_bytes_to_part(pdf_bytes: bytes) -> types.Part:
    return types.Part.from_bytes(data=pdf_bytes, mime_type="application/pdf")


def check_client_health() -> tuple[bool, str]:
    try:
        get_client()
        return True, "✅ Gemini client siap"
    except GeminiClientError as e:
        return False, str(e)