"""
Search Tools for Product Discovery

- search_products is created via make_search_products_tool(session_id, registry).
- After search API, an LLM labels each result as Relevant / Partially Relevant / Irrelevant; we count and
  store the curated list in the registry, return [SEARCH_REF:ref_id] + quality counts + top10 titles.
"""

import base64
import json
import logging
import os
from pathlib import Path
from typing import Optional

import requests
from langchain_core.tools import tool
from openai import OpenAI

from app.config import settings
from app.search_registry import (
    ProductItem,
    SearchResult,
    SearchResultRegistry,
    global_registry,
    new_ref_id,
)

logger = logging.getLogger(__name__)

_openai_client: Optional[OpenAI] = None


def _normalize_image_url(url: Optional[str]) -> Optional[str]:
    """Normalize image_url from API (e.g. ////cnres.appracle.com/... → https://cnres.appracle.com/...)."""
    if not url or not isinstance(url, str):
        return None
    url = url.strip()
    if not url:
        return None
    if url.startswith("https://") or url.startswith("http://"):
        return url
    # // or ////host/path → https://host/path (exactly one "//" after scheme)
    if url.startswith("/"):
        return "https://" + url.lstrip("/")
    return "https://" + url


def get_openai_client() -> OpenAI:
    global _openai_client
    if _openai_client is None:
        kwargs = {"api_key": settings.openai_api_key}
        if settings.openai_api_base_url:
            kwargs["base_url"] = settings.openai_api_base_url
        _openai_client = OpenAI(**kwargs)
    return _openai_client


# ── LLM quality assessment ─────────────────────────────────────────────────────

def _assess_search_quality(query: str, raw_products: list) -> tuple[list[str], str]:
    """
    Use LLM to label each search result and write a short quality_summary.
    Returns (labels, quality_summary). labels: one per product; quality_summary: 1–2 sentences.
    """
    n = len(raw_products)
    if n == 0:
        return [], ""

    lines = []
    for i, p in enumerate(raw_products, 1):
        title = (p.get("title") or "")[:60]
        lines.append(f"{i}. {title}")
    product_text = "\n".join(lines)

    prompt = f"""评估以下搜索结果与用户查询的匹配程度，完成两件事：
1. 为每条结果打一个等级：Relevant / Partially Relevant / Irrelevant。
2. 写一段 quality_summary（1–2 句话）：简要说明搜索结果主要包含哪些商品、是否基本满足搜索意图、整体匹配度如何。

用户查询：{query}

搜索结果（共 {n} 条）：
{product_text}

等级说明：Relevant=完全符合查询意图；Partially Relevant=基本相关（如品类等主需求匹配但部分属性不完全符合）；Irrelevant=不相关。

请严格按以下 JSON 输出，仅输出 JSON，无其他内容：
{{"labels": ["Relevant", "Partially Relevant", "Irrelevant", ...], "quality_summary": "你的1-2句总结"}}
labels 数组长度必须等于 {n}。"""

    try:
        client = get_openai_client()
        resp = client.chat.completions.create(
            model=settings.openai_model,
            messages=[{"role": "user", "content": prompt}],
            max_tokens=1200,
            temperature=0.1,
        )
        raw = resp.choices[0].message.content.strip()
        if raw.startswith("```"):
            raw = raw.split("```")[1]
            if raw.startswith("json"):
                raw = raw[4:]
        raw = raw.strip()
        data = json.loads(raw)
        labels = data.get("labels", [])
        valid = {"Relevant", "Partially Relevant", "Irrelevant"}
        labels = [l if l in valid else "Partially Relevant" for l in labels]
        while len(labels) < n:
            labels.append("Partially Relevant")
        quality_summary = (data.get("quality_summary") or "").strip() or ""
        return labels[:n], quality_summary
    except Exception as e:
        logger.warning(f"Quality assessment failed: {e}; using fallback.")
        return ["Partially Relevant"] * n, ""


# ── Tool factory ───────────────────────────────────────────────────────────────

def make_search_products_tool(
    session_id: str,
    registry: SearchResultRegistry,
):
    """
    Return a search_products tool bound to a specific session and registry.

    The tool:
    1. Calls the product search API.
    2. Runs LLM quality assessment on up to 20 results.
    3. Stores a SearchResult in the registry.
    4. Returns a concise quality summary + [SEARCH_REF:ref_id].
    """

    @tool
    def search_products(query: str, limit: int = 20) -> str:
        """搜索商品库并做质量评估：LLM 为每条结果打等级（Relevant / Partially Relevant / Irrelevant），返回引用与 top10 标题。

        Args:
            query: 自然语言商品描述
            limit: 最多返回条数（1-20）

        Returns:
            【搜索完成】+ 结果引用 [SEARCH_REF:ref_id] + 质量情况（评估条数、Relevant/Partially Relevant 数）+ results list（top10 标题）
        """
        try:
            logger.info(f"[{session_id}] search_products: query={query!r} limit={limit}")

            url = f"{settings.search_api_base_url.rstrip('/')}/search/"
            headers = {
                "Content-Type": "application/json",
                "X-Tenant-ID": settings.search_api_tenant_id,
            }
            payload = {
                "query": query,
                "size": min(max(limit, 1), 20),
                "from": 0,
                "language": "zh",
                "enable_rerank": True,
                "rerank_query_template": query,
                "rerank_doc_template": "{title}",
            }

            resp = requests.post(url, json=payload, headers=headers, timeout=60)
            if resp.status_code != 200:
                logger.error(f"Search API error {resp.status_code}: {resp.text[:300]}")
                return f"搜索失败：API 返回状态码 {resp.status_code}，请稍后重试。"

            data = resp.json()
            raw_results: list = data.get("results", [])
            total_hits: int = data.get("total", 0)

            if not raw_results:
                return (
                    f"【搜索完成】query='{query}'\n"
                    "未找到匹配商品，建议换用更宽泛或不同角度的关键词重新搜索。"
                )

            labels, quality_summary = _assess_search_quality(query, raw_results)
            perfect_count = sum(1 for l in labels if l == "Relevant")
            partial_count = sum(1 for l in labels if l == "Partially Relevant")
            irrelevant_count = len(labels) - perfect_count - partial_count

            products: list[ProductItem] = []
            for raw, label in zip(raw_results, labels):
                if label not in ("Relevant", "Partially Relevant"):
                    continue
                products.append(
                    ProductItem(
                        spu_id=str(raw.get("spu_id", "")),
                        title=raw.get("title") or "",
                        price=raw.get("price"),
                        category_path=(
                            raw.get("category_path") or raw.get("category_name")
                        ),
                        vendor=raw.get("vendor"),
                        image_url=_normalize_image_url(raw.get("image_url")),
                        relevance_score=raw.get("relevance_score"),
                        match_label=label,
                        tags=raw.get("tags") or [],
                        specifications=raw.get("specifications") or [],
                    )
                )

            ref_id = new_ref_id()
            result = SearchResult(
                ref_id=ref_id,
                query=query,
                total_api_hits=total_hits,
                returned_count=len(raw_results),
                perfect_count=perfect_count,
                partial_count=partial_count,
                irrelevant_count=irrelevant_count,
                quality_summary=quality_summary,
                products=products,
            )
            registry.register(session_id, result)
            assessed_n = len(raw_results)
            logger.info(
                "[%s] Registered %s: query=%s assessed=%s perfect=%s partial=%s",
                session_id, ref_id, query, assessed_n, perfect_count, partial_count,
            )

            top10_titles = [
                (raw.get("title") or "未知")[:80]
                for raw in raw_results[:10]
            ]
            results_list = "\n".join(f"{i}. {t}" for i, t in enumerate(top10_titles, 1))

            return (
                f"【搜索完成】query='{query}'\n"
                f"结果引用：[SEARCH_REF:{ref_id}]\n"
                f"搜索结果质量情况：评估总条数{assessed_n}条，Relevant {perfect_count} 条，Partially Relevant {partial_count} 条。\n"
                f"results list:\n{results_list}"
            )

        except requests.exceptions.RequestException as e:
            logger.error(f"[{session_id}] Search network error: {e}", exc_info=True)
            return f"搜索失败（网络错误）：{e}"
        except Exception as e:
            logger.error(f"[{session_id}] Search error: {e}", exc_info=True)
            return f"搜索失败：{e}"

    return search_products


# ── Standalone tools (no session binding needed) ───────────────────────────────

@tool
def web_search(query: str) -> str:
    """使用 Tavily 进行通用 Web 搜索，补充外部/实时知识。

    触发场景：
    - 需要**外部知识**：流行趋势、品牌、搭配文化、节日习俗等
    - 需要**实时/及时信息**：所有与天气相关的问题、当季流行元素、某地近期或者未来的事件、所有依赖当前时间相关的信息
    - 需要**宏观参考**：不同场合/国家的穿着建议、选购攻略

    Args:
        query: 要搜索的问题，自然语言描述

    Returns:
        总结后的回答 + 若干参考来源链接
    """
    try:
        api_key = os.getenv("TAVILY_API_KEY")
        if not api_key:
            return (
                "无法调用外部 Web 搜索：未检测到 TAVILY_API_KEY 环境变量。\n"
                "请在运行环境中配置 TAVILY_API_KEY 后再重试。"
            )

        logger.info(f"web_search: {query!r}")

        url = "https://api.tavily.com/search"
        headers = {
            "Authorization": f"Bearer {api_key}",
            "Content-Type": "application/json",
        }
        payload = {
            "query": query,
            "search_depth": "advanced",
            "include_answer": True,
        }
        response = requests.post(url, json=payload, headers=headers, timeout=60)

        if response.status_code != 200:
            return f"调用外部 Web 搜索失败：Tavily 返回状态码 {response.status_code}"

        data = response.json()
        answer = data.get("answer") or "（Tavily 未返回直接回答，仅返回了搜索结果。）"
        results = data.get("results") or []

        output_lines = [
            "【外部 Web 搜索结果（Tavily）】",
            "",
            "回答摘要：",
            answer.strip(),
        ]
        if results:
            output_lines.append("")
            output_lines.append("参考来源（部分）：")
            for idx, item in enumerate(results[:5], 1):
                title = item.get("title") or "无标题"
                link = item.get("url") or ""
                output_lines.append(f"{idx}. {title}")
                if link:
                    output_lines.append(f"   链接: {link}")

        return "\n".join(output_lines).strip()

    except requests.exceptions.RequestException as e:
        logger.error("web_search network error: %s", e, exc_info=True)
        return f"调用外部 Web 搜索失败（网络错误）：{e}"
    except Exception as e:
        logger.error("web_search error: %s", e, exc_info=True)
        return f"调用外部 Web 搜索失败：{e}"


@tool
def analyze_image_style(image_path: str) -> str:
    """分析用户上传的商品图片，提取视觉风格属性，用于后续商品搜索。

    适用场景：
    - 用户上传图片，想找相似商品
    - 需要理解图片中商品的风格、颜色、材质等属性

    Args:
        image_path: 图片文件路径

    Returns:
        商品视觉属性的详细文字描述，可直接作为 search_products 的 query
    """
    try:
        logger.info(f"analyze_image_style: {image_path!r}")

        img_path = Path(image_path)
        if not img_path.exists():
            return f"错误：图片文件不存在：{image_path}"

        with open(img_path, "rb") as f:
            image_data = base64.b64encode(f.read()).decode("utf-8")

        prompt = """请分析这张商品图片，提供详细的视觉属性描述，用于商品搜索。

请包含：
- 商品类型（如：连衣裙、运动鞋、双肩包、西装等）
- 主要颜色
- 风格定位（如：休闲、正式、运动、复古、现代简约等）
- 图案/纹理（如：纯色、条纹、格纹、碎花、几何图案等）
- 关键设计特征（如：领型、袖长、版型、材质外观等）
- 适用场合（如：办公、户外、度假、聚会、运动等）

输出格式：3-4句自然语言描述，可直接用作搜索关键词。"""

        client = get_openai_client()
        response = client.chat.completions.create(
            model=settings.openai_vision_model,
            messages=[
                {
                    "role": "user",
                    "content": [
                        {"type": "text", "text": prompt},
                        {
                            "type": "image_url",
                            "image_url": {
                                "url": f"data:image/jpeg;base64,{image_data}",
                                "detail": "high",
                            },
                        },
                    ],
                }
            ],
            max_tokens=800,
            temperature=0.3,
        )

        analysis = response.choices[0].message.content.strip()
        logger.info("Image analysis completed.")
        return analysis

    except Exception as e:
        logger.error(f"analyze_image_style error: {e}", exc_info=True)
        return f"图片分析失败：{e}"


# ── Tool list factory ──────────────────────────────────────────────────────────

def get_all_tools(
    session_id: str = "default",
    registry: Optional[SearchResultRegistry] = None,
) -> list:
    """
    Return all agent tools.

    search_products is session-bound (factory); other tools are stateless.
    """
    if registry is None:
        registry = global_registry
    return [
        make_search_products_tool(session_id, registry),
        analyze_image_style,
        web_search,
    ]