# -*- coding: utf-8 -*-
"""LLM 命名实体识别 (NER) 算子。

基于大语言模型从文本中识别命名实体（人名、地名、机构名等），
输出实体列表（含文本片段、实体类型、在原文中的起止位置）。
"""

import json
import os
import shutil
import time
from typing import Any, Dict, List

from loguru import logger

from datamate.core.base_op import Mapper


SYSTEM_PROMPT = (
    "你是一个专业的命名实体识别（NER）专家。根据给定的实体类型列表，"
    "从输入文本中识别所有命名实体。\n"
    "你必须严格输出 JSON 格式，不要输出任何其他内容。"
)

USER_PROMPT_TEMPLATE = """请从以下文本中识别所有命名实体。

实体类型列表：{entity_types}

实体类型说明：
- PER：人名
- ORG：组织/机构名
- LOC：地点/地名
- DATE：日期/时间
- EVENT：事件
- PRODUCT：产品名
- MONEY：金额
- PERCENT：百分比

文本内容：
{text}

请以如下 JSON 格式输出（entities 为实体数组，每个实体包含 text、type、start、end 四个字段）：
{{"entities": [{{"text": "实体文本", "type": "PER", "start": 0, "end": 3}}]}}

注意：
- type 必须是实体类型列表中的值之一
- start 和 end 是实体在原文中的字符偏移位置（从 0 开始，左闭右开）
- 如果没有找到任何实体，返回 {{"entities": []}}"""


class LLMNamedEntityRecognition(Mapper):
    """基于 LLM 的命名实体识别算子。"""

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self._model_id: str = kwargs.get("modelId", "")
        self._entity_types: str = kwargs.get("entityTypes", "PER,ORG,LOC,DATE")
        self._output_dir: str = kwargs.get("outputDir", "") or ""
        self._llm_config = None

    def _get_llm_config(self) -> Dict[str, Any]:
        if self._llm_config is None:
            from ops.annotation._llm_utils import get_llm_config

            self._llm_config = get_llm_config(self._model_id)
        return self._llm_config

    @staticmethod
    def _validate_entities(
        entities_raw: Any, allowed_types: List[str]
    ) -> List[Dict[str, Any]]:
        """校验并过滤实体列表，确保类型在允许范围内。"""

        if not isinstance(entities_raw, list):
            return []

        validated: List[Dict[str, Any]] = []
        allowed_set = {t.strip().upper() for t in allowed_types}

        for ent in entities_raw:
            if not isinstance(ent, dict):
                continue
            ent_type = str(ent.get("type", "")).strip().upper()
            ent_text = str(ent.get("text", "")).strip()
            if not ent_text:
                continue
            # 保留匹配的类型，或在类型列表为空时全部保留
            if allowed_set and ent_type not in allowed_set:
                continue
            validated.append(
                {
                    "text": ent_text,
                    "type": ent_type,
                    "start": ent.get("start"),
                    "end": ent.get("end"),
                }
            )
        return validated

    def execute(self, sample: Dict[str, Any]) -> Dict[str, Any]:
        start = time.time()

        text_path = sample.get(self.text_key)
        if not text_path or not os.path.exists(str(text_path)):
            logger.warning("Text file not found: {}", text_path)
            return sample

        text_path = str(text_path)
        with open(text_path, "r", encoding="utf-8") as f:
            text_content = f.read()

        if not text_content.strip():
            logger.warning("Empty text file: {}", text_path)
            return sample

        max_chars = 8000
        truncated = text_content[:max_chars]

        from ops.annotation._llm_utils import call_llm, extract_json

        config = self._get_llm_config()
        prompt = USER_PROMPT_TEMPLATE.format(
            entity_types=self._entity_types,
            text=truncated,
        )

        allowed_types = [t.strip() for t in self._entity_types.split(",") if t.strip()]

        try:
            raw_response = call_llm(config, prompt, system_prompt=SYSTEM_PROMPT)
            parsed = extract_json(raw_response)
            entities_raw = parsed.get("entities", []) if isinstance(parsed, dict) else parsed
            entities = self._validate_entities(entities_raw, allowed_types)
        except Exception as e:
            logger.error("LLM NER failed for {}: {}", text_path, e)
            entities = []

        annotation = {
            "file": os.path.basename(text_path),
            "task_type": "ner",
            "entity_types": self._entity_types,
            "model": config.get("model_name", ""),
            "entities": entities,
        }

        # 写入输出
        output_dir = self._output_dir or os.path.dirname(text_path)
        annotations_dir = os.path.join(output_dir, "annotations")
        data_dir = os.path.join(output_dir, "data")
        os.makedirs(annotations_dir, exist_ok=True)
        os.makedirs(data_dir, exist_ok=True)

        base_name = os.path.splitext(os.path.basename(text_path))[0]

        dst_data = os.path.join(data_dir, os.path.basename(text_path))
        if not os.path.exists(dst_data):
            shutil.copy2(text_path, dst_data)

        json_path = os.path.join(annotations_dir, f"{base_name}.json")
        with open(json_path, "w", encoding="utf-8") as f:
            json.dump(annotation, f, indent=2, ensure_ascii=False)

        sample["detection_count"] = len(entities)
        sample["annotations_file"] = json_path
        sample["annotations"] = annotation

        elapsed = time.time() - start
        logger.info(
            "NER: {} -> {} entities, Time: {:.2f}s",
            os.path.basename(text_path),
            len(entities),
            elapsed,
        )
        return sample