"""AstrBot 数据导出器

负责将所有数据导出为 ZIP 备份文件。
导出格式为 JSON，这是数据库无关的方案，支持未来向 MySQL/PostgreSQL 迁移。
"""

import hashlib
import json
import os
import zipfile
from datetime import datetime, timezone
from pathlib import Path
from typing import TYPE_CHECKING, Any

from sqlalchemy import select

from astrbot.core import logger
from astrbot.core.config.default import VERSION
from astrbot.core.db import BaseDatabase
from astrbot.core.utils.astrbot_path import (
    get_astrbot_backups_path,
    get_astrbot_data_path,
)

# 从共享常量模块导入
from .constants import (
    BACKUP_MANIFEST_VERSION,
    KB_METADATA_MODELS,
    MAIN_DB_MODELS,
    get_backup_directories,
)

if TYPE_CHECKING:
    from astrbot.core.knowledge_base.kb_mgr import KnowledgeBaseManager

CMD_CONFIG_FILE_PATH = os.path.join(get_astrbot_data_path(), "cmd_config.json")


class AstrBotExporter:
    """AstrBot 数据导出器

    导出内容：
    - 主数据库所有表（data/data_v4.db）
    - 知识库元数据（data/knowledge_base/kb.db）
    - 每个知识库的向量文档数据
    - 配置文件（data/cmd_config.json）
    - 附件文件
    - 知识库多媒体文件
    - 插件目录（data/plugins）
    - 插件数据目录（data/plugin_data）
    - 配置目录（data/config）
    - T2I 模板目录（data/t2i_templates）
    - WebChat 数据目录（data/webchat）
    - 临时文件目录（data/temp）
    """

    def __init__(
        self,
        main_db: BaseDatabase,
        kb_manager: "KnowledgeBaseManager | None" = None,
        config_path: str = CMD_CONFIG_FILE_PATH,
    ) -> None:
        self.main_db = main_db
        self.kb_manager = kb_manager
        self.config_path = config_path
        self._checksums: dict[str, str] = {}

    async def export_all(
        self,
        output_dir: str | None = None,
        progress_callback: Any | None = None,
    ) -> str:
        """导出所有数据到 ZIP 文件

        Args:
            output_dir: 输出目录
            progress_callback: 进度回调函数，接收参数 (stage, current, total, message)

        Returns:
            str: 生成的 ZIP 文件路径
        """
        if output_dir is None:
            output_dir = get_astrbot_backups_path()

        # 确保输出目录存在
        Path(output_dir).mkdir(parents=True, exist_ok=True)

        timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
        zip_filename = f"astrbot_backup_{timestamp}.zip"
        zip_path = os.path.join(output_dir, zip_filename)

        logger.info(f"开始导出备份到 {zip_path}")

        try:
            with zipfile.ZipFile(zip_path, "w", zipfile.ZIP_DEFLATED) as zf:
                # 1. 导出主数据库
                if progress_callback:
                    await progress_callback("main_db", 0, 100, "正在导出主数据库...")
                main_data = await self._export_main_database()
                main_db_json = json.dumps(
                    main_data, ensure_ascii=False, indent=2, default=str
                )
                zf.writestr("databases/main_db.json", main_db_json)
                self._add_checksum("databases/main_db.json", main_db_json)
                if progress_callback:
                    await progress_callback("main_db", 100, 100, "主数据库导出完成")

                # 2. 导出知识库数据
                kb_meta_data: dict[str, Any] = {
                    "knowledge_bases": [],
                    "kb_documents": [],
                    "kb_media": [],
                }
                if self.kb_manager:
                    if progress_callback:
                        await progress_callback(
                            "kb_metadata", 0, 100, "正在导出知识库元数据..."
                        )
                    kb_meta_data = await self._export_kb_metadata()
                    kb_meta_json = json.dumps(
                        kb_meta_data, ensure_ascii=False, indent=2, default=str
                    )
                    zf.writestr("databases/kb_metadata.json", kb_meta_json)
                    self._add_checksum("databases/kb_metadata.json", kb_meta_json)
                    if progress_callback:
                        await progress_callback(
                            "kb_metadata", 100, 100, "知识库元数据导出完成"
                        )

                    # 导出每个知识库的文档数据
                    kb_insts = self.kb_manager.kb_insts
                    total_kbs = len(kb_insts)
                    for idx, (kb_id, kb_helper) in enumerate(kb_insts.items()):
                        if progress_callback:
                            await progress_callback(
                                "kb_documents",
                                idx,
                                total_kbs,
                                f"正在导出知识库 {kb_helper.kb.kb_name} 的文档数据...",
                            )
                        doc_data = await self._export_kb_documents(kb_helper)
                        doc_json = json.dumps(
                            doc_data, ensure_ascii=False, indent=2, default=str
                        )
                        doc_path = f"databases/kb_{kb_id}/documents.json"
                        zf.writestr(doc_path, doc_json)
                        self._add_checksum(doc_path, doc_json)

                        # 导出 FAISS 索引文件
                        await self._export_faiss_index(zf, kb_helper, kb_id)

                        # 导出知识库多媒体文件
                        await self._export_kb_media_files(zf, kb_helper, kb_id)

                    if progress_callback:
                        await progress_callback(
                            "kb_documents", total_kbs, total_kbs, "知识库文档导出完成"
                        )

                # 3. 导出配置文件
                if progress_callback:
                    await progress_callback("config", 0, 100, "正在导出配置文件...")
                if os.path.exists(self.config_path):
                    with open(self.config_path, encoding="utf-8") as f:
                        config_content = f.read()
                    zf.writestr("config/cmd_config.json", config_content)
                    self._add_checksum("config/cmd_config.json", config_content)
                if progress_callback:
                    await progress_callback("config", 100, 100, "配置文件导出完成")

                # 4. 导出附件文件
                if progress_callback:
                    await progress_callback("attachments", 0, 100, "正在导出附件...")
                await self._export_attachments(zf, main_data.get("attachments", []))
                if progress_callback:
                    await progress_callback("attachments", 100, 100, "附件导出完成")

                # 5. 导出插件和其他目录
                if progress_callback:
                    await progress_callback(
                        "directories", 0, 100, "正在导出插件和数据目录..."
                    )
                dir_stats = await self._export_directories(zf)
                if progress_callback:
                    await progress_callback("directories", 100, 100, "目录导出完成")

                # 6. 生成 manifest
                if progress_callback:
                    await progress_callback("manifest", 0, 100, "正在生成清单...")
                manifest = self._generate_manifest(main_data, kb_meta_data, dir_stats)
                manifest_json = json.dumps(manifest, ensure_ascii=False, indent=2)
                zf.writestr("manifest.json", manifest_json)
                if progress_callback:
                    await progress_callback("manifest", 100, 100, "清单生成完成")

            logger.info(f"备份导出完成: {zip_path}")
            return zip_path

        except Exception as e:
            logger.error(f"备份导出失败: {e}")
            # 清理失败的文件
            if os.path.exists(zip_path):
                os.remove(zip_path)
            raise

    async def _export_main_database(self) -> dict[str, list[dict]]:
        """导出主数据库所有表"""
        export_data: dict[str, list[dict]] = {}

        async with self.main_db.get_db() as session:
            for table_name, model_class in MAIN_DB_MODELS.items():
                try:
                    result = await session.execute(select(model_class))
                    records = result.scalars().all()
                    export_data[table_name] = [
                        self._model_to_dict(record) for record in records
                    ]
                    logger.debug(
                        f"导出表 {table_name}: {len(export_data[table_name])} 条记录"
                    )
                except Exception as e:
                    logger.warning(f"导出表 {table_name} 失败: {e}")
                    export_data[table_name] = []

        return export_data

    async def _export_kb_metadata(self) -> dict[str, list[dict]]:
        """导出知识库元数据库"""
        if not self.kb_manager:
            return {"knowledge_bases": [], "kb_documents": [], "kb_media": []}

        export_data: dict[str, list[dict]] = {}

        async with self.kb_manager.kb_db.get_db() as session:
            for table_name, model_class in KB_METADATA_MODELS.items():
                try:
                    result = await session.execute(select(model_class))
                    records = result.scalars().all()
                    export_data[table_name] = [
                        self._model_to_dict(record) for record in records
                    ]
                    logger.debug(
                        f"导出知识库表 {table_name}: {len(export_data[table_name])} 条记录"
                    )
                except Exception as e:
                    logger.warning(f"导出知识库表 {table_name} 失败: {e}")
                    export_data[table_name] = []

        return export_data

    async def _export_kb_documents(self, kb_helper: Any) -> dict[str, Any]:
        """导出知识库的文档块数据"""
        try:
            from astrbot.core.db.vec_db.faiss_impl.vec_db import FaissVecDB

            vec_db: FaissVecDB = kb_helper.vec_db
            if not vec_db or not vec_db.document_storage:
                return {"documents": []}

            # 获取所有文档
            docs = await vec_db.document_storage.get_documents(
                metadata_filters={},
                offset=0,
                limit=None,  # 获取全部
            )

            return {"documents": docs}
        except Exception as e:
            logger.warning(f"导出知识库文档失败: {e}")
            return {"documents": []}

    async def _export_faiss_index(
        self,
        zf: zipfile.ZipFile,
        kb_helper: Any,
        kb_id: str,
    ) -> None:
        """导出 FAISS 索引文件"""
        try:
            index_path = kb_helper.kb_dir / "index.faiss"
            if index_path.exists():
                archive_path = f"databases/kb_{kb_id}/index.faiss"
                zf.write(str(index_path), archive_path)
                logger.debug(f"导出 FAISS 索引: {archive_path}")
        except Exception as e:
            logger.warning(f"导出 FAISS 索引失败: {e}")

    async def _export_kb_media_files(
        self, zf: zipfile.ZipFile, kb_helper: Any, kb_id: str
    ) -> None:
        """导出知识库的多媒体文件"""
        try:
            media_dir = kb_helper.kb_medias_dir
            if not media_dir.exists():
                return

            for root, _, files in os.walk(media_dir):
                for file in files:
                    file_path = Path(root) / file
                    # 计算相对路径
                    rel_path = file_path.relative_to(kb_helper.kb_dir)
                    archive_path = f"files/kb_media/{kb_id}/{rel_path}"
                    zf.write(str(file_path), archive_path)
        except Exception as e:
            logger.warning(f"导出知识库媒体文件失败: {e}")

    async def _export_directories(
        self, zf: zipfile.ZipFile
    ) -> dict[str, dict[str, int]]:
        """导出插件和其他数据目录

        Returns:
            dict: 每个目录的统计信息 {dir_name: {"files": count, "size": bytes}}
        """
        stats: dict[str, dict[str, int]] = {}
        backup_directories = get_backup_directories()

        for dir_name, dir_path in backup_directories.items():
            full_path = Path(dir_path)
            if not full_path.exists():
                logger.debug(f"目录不存在，跳过: {full_path}")
                continue

            file_count = 0
            total_size = 0

            try:
                for root, dirs, files in os.walk(full_path):
                    # 跳过 __pycache__ 目录
                    dirs[:] = [d for d in dirs if d != "__pycache__"]

                    for file in files:
                        # 跳过 .pyc 文件
                        if file.endswith(".pyc"):
                            continue

                        file_path = Path(root) / file
                        try:
                            # 计算相对路径
                            rel_path = file_path.relative_to(full_path)
                            archive_path = f"directories/{dir_name}/{rel_path}"
                            zf.write(str(file_path), archive_path)
                            file_count += 1
                            total_size += file_path.stat().st_size
                        except Exception as e:
                            logger.warning(f"导出文件 {file_path} 失败: {e}")

                stats[dir_name] = {"files": file_count, "size": total_size}
                logger.debug(
                    f"导出目录 {dir_name}: {file_count} 个文件, {total_size} 字节"
                )
            except Exception as e:
                logger.warning(f"导出目录 {dir_path} 失败: {e}")
                stats[dir_name] = {"files": 0, "size": 0}

        return stats

    async def _export_attachments(
        self, zf: zipfile.ZipFile, attachments: list[dict]
    ) -> None:
        """导出附件文件"""
        for attachment in attachments:
            try:
                file_path = attachment.get("path", "")
                if file_path and os.path.exists(file_path):
                    # 使用 attachment_id 作为文件名
                    attachment_id = attachment.get("attachment_id", "")
                    ext = os.path.splitext(file_path)[1]
                    archive_path = f"files/attachments/{attachment_id}{ext}"
                    zf.write(file_path, archive_path)
            except Exception as e:
                logger.warning(f"导出附件失败: {e}")

    def _model_to_dict(self, record: Any) -> dict:
        """将 SQLModel 实例转换为字典

        这是数据库无关的序列化方式，支持未来迁移到其他数据库。
        """
        # 使用 SQLModel 内置的 model_dump 方法（如果可用）
        if hasattr(record, "model_dump"):
            data = record.model_dump(mode="python")
            # 处理 datetime 类型
            for key, value in data.items():
                if isinstance(value, datetime):
                    data[key] = value.isoformat()
            return data

        # 回退到手动提取
        data = {}
        # 使用 inspect 获取表信息
        from sqlalchemy import inspect as sa_inspect

        mapper = sa_inspect(record.__class__)
        for column in mapper.columns:
            value = getattr(record, column.name)
            # 处理 datetime 类型 - 统一转为 ISO 格式字符串
            if isinstance(value, datetime):
                value = value.isoformat()
            data[column.name] = value
        return data

    def _add_checksum(self, path: str, content: str | bytes) -> None:
        """计算并添加文件校验和"""
        if isinstance(content, str):
            content = content.encode("utf-8")
        checksum = hashlib.sha256(content).hexdigest()
        self._checksums[path] = f"sha256:{checksum}"

    def _generate_manifest(
        self,
        main_data: dict[str, list[dict]],
        kb_meta_data: dict[str, list[dict]],
        dir_stats: dict[str, dict[str, int]] | None = None,
    ) -> dict:
        """生成备份清单"""
        if dir_stats is None:
            dir_stats = {}
        # 收集知识库 ID
        kb_document_tables = {}
        if self.kb_manager:
            for kb_id in self.kb_manager.kb_insts.keys():
                kb_document_tables[kb_id] = "documents"

        # 收集附件文件列表
        attachment_files = []
        for attachment in main_data.get("attachments", []):
            attachment_id = attachment.get("attachment_id", "")
            path = attachment.get("path", "")
            if attachment_id and path:
                ext = os.path.splitext(path)[1]
                attachment_files.append(f"{attachment_id}{ext}")

        # 收集知识库媒体文件
        kb_media_files: dict[str, list[str]] = {}
        if self.kb_manager:
            for kb_id, kb_helper in self.kb_manager.kb_insts.items():
                media_files: list[str] = []
                media_dir = kb_helper.kb_medias_dir
                if media_dir.exists():
                    for root, _, files in os.walk(media_dir):
                        for file in files:
                            media_files.append(file)
                if media_files:
                    kb_media_files[kb_id] = media_files

        manifest = {
            "version": BACKUP_MANIFEST_VERSION,
            "astrbot_version": VERSION,
            "exported_at": datetime.now(timezone.utc).isoformat(),
            "origin": "exported",  # 标记备份来源：exported=本实例导出, uploaded=用户上传
            "schema_version": {
                "main_db": "v4",
                "kb_db": "v1",
            },
            "tables": {
                "main_db": list(main_data.keys()),
                "kb_metadata": list(kb_meta_data.keys()),
                "kb_documents": kb_document_tables,
            },
            "files": {
                "attachments": attachment_files,
                "kb_media": kb_media_files,
            },
            "directories": list(dir_stats.keys()),
            "checksums": self._checksums,
            "statistics": {
                "main_db": {
                    table: len(records) for table, records in main_data.items()
                },
                "kb_metadata": {
                    table: len(records) for table, records in kb_meta_data.items()
                },
                "directories": dir_stats,
            },
        }

        return manifest