#!/usr/bin/env python3
"""Notion semantic search — query expansion + LLM rerank over Notion API search.

CLI: python3 notion_search.py "query" [--databases ID,...] [--filter JSON] \
                                       [--limit N] [--no-rerank] [--no-expand] \
                                       [--no-cache] [--json]
"""

from __future__ import annotations

import json
import re
import sys
from typing import Callable, List, Optional

from _search_llm import call_claude as default_llm_caller

EXPAND_PROMPT = """You are a query expander for a Notion semantic search tool. Generate up to {n} variants of the user's query that capture related concepts, synonyms, and cross-language alternates (especially Korean ↔ English).

Rules:
- Always include the original query verbatim as the first variant.
- Variants should help find pages that the original query might miss due to keyword-only search.
- For Korean queries, include English synonyms; for English queries, include Korean alternates if the topic has common Korean usage.
- Keep variants concise (under 8 words each).

Query: {query}

Return ONLY a JSON array of strings, no prose. Example:
["original query", "synonym variant", "cross-language variant"]"""


def expand_query(
    query: str,
    *,
    llm_caller: Optional[Callable[..., str]] = None,
    max_variants: int = 5,
) -> List[str]:
    """Expand a query into related variants. Returns [query] on any failure."""
    if llm_caller is None:
        llm_caller = default_llm_caller

    prompt = EXPAND_PROMPT.format(n=max_variants, query=query)

    try:
        response = llm_caller(prompt)
    except Exception as exc:
        print(f"Warning: query expansion failed ({exc}); using original query only",
              file=sys.stderr)
        return [query]

    # Be permissive: extract the first JSON array from the response.
    match = re.search(r'\[.*\]', response, re.DOTALL)
    if not match:
        print("Warning: query expansion returned no JSON array; using original query only",
              file=sys.stderr)
        return [query]

    try:
        variants = json.loads(match.group(0))
    except json.JSONDecodeError:
        print("Warning: query expansion returned invalid JSON; using original query only",
              file=sys.stderr)
        return [query]

    if not isinstance(variants, list) or not all(isinstance(v, str) for v in variants):
        print("Warning: query expansion returned non-string-list shape; using original query only",
              file=sys.stderr)
        return [query]

    # Always include the original query first; dedupe; cap at max_variants.
    seen = set()
    result = []
    for v in [query] + variants:
        v = v.strip()
        if v and v not in seen:
            seen.add(v)
            result.append(v)
        if len(result) >= max_variants:
            break
    return result