import json
import os
from typing import Dict, List, Optional

import httpx

from config import Config


def _build_document_for_table(table: str, templates: List[str]) -> str:
    lines = [f"table: {table}"]
    for t in templates:
        lines.append(f"- {t}")
    return "\n".join(lines)


def _build_sql_gen_document(table: str, prompt: Dict[str, any]) -> str:
    system_prompt = prompt.get("system_prompt", "")
    business_prompt = prompt.get("business_prompt", "")
    constraints = prompt.get("constraints", [])
    lines = [f"table: {table}"]
    if system_prompt:
        lines.append("[system] " + system_prompt)
    if business_prompt:
        lines.append("[business] " + business_prompt)
    if constraints:
        lines.append("[constraints]")
        for c in constraints:
            lines.append(f"- {c}")
    return "\n".join(lines)


class RagflowSync:
    """RAGFlow 同步工具"""

    def __init__(self):
        cfg = Config.get_section("ragflow")
        self._base_url = cfg.get("url", "").rstrip("/")
        self._api_key = cfg.get("api_key", "")
        self._table_retrieval_dataset_id = (cfg.get("table_retrieval_dataset_id") or "").strip()
        self._sql_gen_dataset_id = (cfg.get("sql_gen_dataset_id") or "").strip()
        self._upload_path = (cfg.get("upload") or "").strip()
        self._upload_mode = (cfg.get("upload_mode") or "overwrite").strip().lower()

    def _validate_common(self) -> None:
        if not self._base_url:
            raise RuntimeError("未配置 ragflow.url")
        if not self._upload_path:
            raise RuntimeError("未配置 ragflow.upload 上传接口，请在 config/config.ini 中设置")
        if self._upload_mode not in ("overwrite", "append"):
            raise RuntimeError("ragflow.upload_mode 仅支持 overwrite 或 append")

    def _post(self, documents: List[Dict[str, any]]):
        self._validate_common()
        url = self._base_url + "/" + self._upload_path.lstrip("/")
        headers = {"Authorization": f"Bearer {self._api_key}"} if self._api_key else {}
        payload: Dict[str, any] = {"documents": documents}
        if self._upload_mode == "overwrite":
            payload["mode"] = "overwrite"
        with httpx.Client(timeout=60) as client:
            response = client.post(url, json=payload, headers=headers)
        response.raise_for_status()
        return response.json()

    def sync_table_retrieval(self) -> Dict[str, any]:
        if not self._table_retrieval_dataset_id:
            raise RuntimeError("未配置 ragflow.table_retrieval_dataset_id，无法同步表名检索模板")
        root = os.path.dirname(os.path.dirname(__file__))
        tables_file = os.path.join(root, "config", "table_retrieval_prompts", "tables.json")
        with open(tables_file, "r", encoding="utf-8") as f:
            data = json.load(f)

        tables = data.get("tables", {})
        documents = []
        for table, templates in tables.items():
            doc = {
                "dataset_ids": self._table_retrieval_dataset_id,
                "content": _build_document_for_table(table, templates),
                "metadata": {"table": table},
            }
            documents.append(doc)

        return self._post(documents)

    def sync_sql_gen_prompts(self) -> Dict[str, any]:
        if not self._sql_gen_dataset_id:
            raise RuntimeError("未配置 ragflow.sql_gen_dataset_id，无法同步 SQL 生成提示词")
        root = os.path.dirname(os.path.dirname(__file__))
        prompts_dir = os.path.join(root, "config", "sql_gen_prompts")
        documents = []

        for name in os.listdir(prompts_dir):
            if not name.endswith(".json"):
                continue
            path = os.path.join(prompts_dir, name)
            with open(path, "r", encoding="utf-8") as f:
                prompt = json.load(f)
            table = prompt.get("table") or os.path.splitext(name)[0]
            doc = {
                "dataset_ids": self._sql_gen_dataset_id,
                "content": _build_sql_gen_document(table, prompt),
                "metadata": {"table": table},
            }
            documents.append(doc)

        return self._post(documents)