import json
import logging

from local_llm_client import chat_completion


SYSTEM_PROMPT = """
You are a Slack assistant.

If a tool is required, respond ONLY in valid JSON:
{
  "tool": "tool_name",
  "arguments": { ... }
}

If no tool is required, respond normally with text.
"""


def try_parse_tool_call(text):
    try:
        data = json.loads(text)
        if isinstance(data, dict) and "tool" in data and "arguments" in data:
            return data
    except json.JSONDecodeError:
        return None
    return None


def process_mention(
    event_data,
    slack_client,
    vector_store,      # qdrant_functions
    bot_profile,
    tool_registry
):
    event = event_data["event"]
    channel = event["channel"]
    user = event["user"]
    text = event["text"]
    ts = event["ts"]
    thread_ts = event.get("thread_ts", ts)

    # ---- RAG retrieval (if enabled) ----
    context_blocks = []
    if getattr(bot_profile, "ENABLE_RAG_RETRIEVAL", True):
        try:
            results = vector_store.search_similar(text, limit=5)
            for r in results:
                context_blocks.append(f"- {r['text']}")
        except Exception as e:
            logging.warning(f"RAG retrieval failed: {e}")

    context_text = "\n".join(context_blocks)

    messages = [
        {"role": "system", "content": SYSTEM_PROMPT},
        {
            "role": "user",
            "content": f"""
Context:
{context_text}

User message:
{text}
"""
        }
    ]

    llm_output = chat_completion(messages)

    # ---- Tool handling ----
    tool_call = try_parse_tool_call(llm_output)

    if tool_call:
        tool_name = tool_call["tool"]
        args = tool_call["arguments"]

        tool_entry = tool_registry.get(tool_name)
        if not tool_entry:
            response_text = f"⚠️ Unknown tool: `{tool_name}`"
        else:
            try:
                result = tool_entry["function"](**args)
                response_text = json.dumps(result, indent=2)
            except Exception as e:
                logging.error(f"Tool execution failed: {e}", exc_info=True)
                response_text = "⚠️ Tool execution failed."
    else:
        response_text = llm_output

    slack_client.chat_postMessage(
        channel=channel,
        text=response_text,
        thread_ts=thread_ts
    )