# services/dify_client.py
import os, json, re, requests
from dotenv import load_dotenv
from flask import current_app

load_dotenv()

DIFY_BASE = os.getenv("DIFY_API_BASE_URL", "https://api.dify.ai/v1")
TIMEOUT = 60

def _post_request(endpoint: str, api_key: str, payload: dict):
    """Generic function to post a request to a Dify endpoint."""
    if not api_key:
        raise RuntimeError("Dify API key is not set")
    
    url = f"{DIFY_BASE}{endpoint}"
    headers = {
        "Authorization": f"Bearer {api_key}",
        "Content-Type": "application/json",
    }
    
    # For debugging the exact payload sent to the API
    current_app.logger.debug(f"Sending Dify request to {url}: {json.dumps(payload, indent=2, ensure_ascii=False)}")
    
    resp = requests.post(url, headers=headers, json=payload, timeout=TIMEOUT)
    
    current_app.logger.debug(f"Dify API Response ({resp.status_code}): {resp.text}")
    
    if resp.status_code != 200:
        resp.raise_for_status()

    data = resp.json()
    return data.get("answer") or data

def translate_text(text: str, target_lang: str, user_id: str = "system") -> str:
    """
    Calls the Dify CHAT API for translation, mimicking a user query.
    """
    api_key = os.getenv("DIFY_TRANSLATOR_API_KEY")
    # Combine all information into a single query string, as expected by the prompt
    query = f"目標語言：{target_lang}\n需翻譯內容：\n{text}"
    
    payload = {
        "inputs": {}, # Chatbot apps generally don't use inputs here
        "response_mode": "blocking",
        "user": user_id,
        "query": query,
        # conversation_id is optional for single-turn interactions
    }
    return _post_request("/chat-messages", api_key, payload)

def summarize_text(text: str, user_id: str = "system") -> str:
    api_key = os.getenv("DIFY_SUMMARIZER_API_KEY")
    payload = {
        "inputs": {}, 
        "response_mode": "blocking",
        "user": user_id,
        "query": text,
    }
    return _post_request("/chat-messages", api_key, payload)

def extract_action_items(text: str, user_id: str = "system") -> list[dict]:
    api_key = os.getenv("DIFY_ACTION_EXTRACTOR_API_KEY")
    
    query = f"請從以下會議記錄中，提取所有行動項目(action items)，並嚴格以JSON格式返回。會議記錄如下：\n\n{text}"
    
    payload = {
        "inputs": {}, 
        "response_mode": "blocking",
        "user": user_id,
        "query": query,
    }
    raw = _post_request("/chat-messages", api_key, payload)

    # Fault tolerance for JSON parsing
    s = str(raw).strip()
    s = re.sub(r"^```(?:json)?|```$", "", s, flags=re.IGNORECASE|re.MULTILINE).strip()
    if not (s.startswith("[") and s.endswith("]")):
        m = re.search(r"[\s\S]*\[[\s\S]*\][\s\S]*", s)
        if m: s = m.group(0)

    items = json.loads(s)
    if not isinstance(items, list):
        raise ValueError("Extractor did not return a list")

    # Normalize keys for database storage
    normalized = []
    for i in items:
        for k in ("item", "action", "owner", "duedate"):
            if k not in i:
                raise ValueError(f"Extractor item is missing required key: {k}")
        normalized.append({
            "item": i["item"],
            "action": i["action"],
            "owner": i["owner"],
            "due_date": i["duedate"],
        })
    return normalized