# -*- coding: utf-8 -*-
"""
DWS 物化视图刷新任务

说明：
    - 按 L1/L2/L3/L4 时间分层刷新物化视图
    - 默认受 dws.mv.enabled 与 dws.retention.* 配置联动控制
"""
from __future__ import annotations

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

from .base_dws_task import BaseDwsTask, TaskContext, TimeLayer


class BaseMvRefreshTask(BaseDwsTask):
    """物化视图刷新基类"""

    BASE_TABLE: str = ""
    DATE_COL: str = ""
    VIEW_PREFIX = "mv_"

    LAYER_ORDER = [
        TimeLayer.LAST_2_DAYS,
        TimeLayer.LAST_1_MONTH,
        TimeLayer.LAST_3_MONTHS,
        TimeLayer.LAST_6_MONTHS,
    ]
    LAYER_SUFFIX = {
        TimeLayer.LAST_2_DAYS: "l1",
        TimeLayer.LAST_1_MONTH: "l2",
        TimeLayer.LAST_3_MONTHS: "l3",
        TimeLayer.LAST_6_MONTHS: "l4",
    }

    def get_target_table(self) -> str:
        return self.BASE_TABLE

    def get_primary_keys(self) -> List[str]:
        return []

    def extract(self, context: TaskContext) -> Dict[str, Any]:
        return {"site_id": context.store_id}

    def transform(self, extracted: Dict[str, Any], context: TaskContext) -> Dict[str, Any]:
        return extracted

    def load(self, transformed: Dict[str, Any], context: TaskContext) -> Dict[str, Any]:
        if not self._is_enabled():
            self.logger.info("%s: 未启用物化刷新，跳过", self.get_task_code())
            return {"counts": {"refreshed": 0}}

        layers = self._resolve_layers()
        refreshed = 0
        details = []

        for layer in layers:
            view_name = self._get_view_name(layer)
            if not view_name:
                continue
            if not self._view_exists(view_name):
                self.logger.warning("%s: 物化视图不存在，跳过 %s", self.get_task_code(), view_name)
                continue
            self._refresh_view(view_name)
            refreshed += 1
            details.append({"view": view_name, "layer": layer.value})

        self.logger.info("%s: 刷新完成，物化视图数=%d", self.get_task_code(), refreshed)
        return {"counts": {"refreshed": refreshed}, "extra": {"details": details}}

    def _is_enabled(self) -> bool:
        enabled = bool(self.config.get("dws.mv.enabled", False))
        if not enabled:
            return False
        tables = self._parse_list(self.config.get("dws.mv.tables"))
        if not tables:
            tables = self._parse_list(self.config.get("dws.retention.tables"))
        if tables and self.BASE_TABLE not in tables:
            return False
        return True

    def _resolve_layers(self) -> List[TimeLayer]:
        # 显式配置优先
        configured = self._parse_layers(self.config.get("dws.mv.layers"))
        if configured:
            return configured

        # 表级覆盖：优先 mv.table_layers，其次 retention.table_layers
        table_layers = self._resolve_layer_map(
            self.config.get("dws.mv.table_layers") or self.config.get("dws.retention.table_layers")
        )
        layer_name = table_layers.get(self.BASE_TABLE)
        if layer_name:
            layer = self._get_layer(layer_name)
            if layer and layer != TimeLayer.ALL:
                return self._layers_up_to(layer)

        # 默认使用 retention.layer
        retention_layer = self._get_layer(self.config.get("dws.retention.layer"))
        if retention_layer and retention_layer != TimeLayer.ALL:
            return self._layers_up_to(retention_layer)

        return list(self.LAYER_ORDER)

    def _layers_up_to(self, target: TimeLayer) -> List[TimeLayer]:
        layers = []
        for layer in self.LAYER_ORDER:
            layers.append(layer)
            if layer == target:
                break
        return layers

    def _get_view_name(self, layer: TimeLayer) -> Optional[str]:
        suffix = self.LAYER_SUFFIX.get(layer)
        if not suffix or not self.BASE_TABLE:
            return None
        return f"{self.VIEW_PREFIX}{self.BASE_TABLE}_{suffix}"

    def _view_exists(self, view_name: str) -> bool:
        sql = "SELECT to_regclass(%s) AS reg"
        rows = self.db.query(sql, (f"{self.DWS_SCHEMA}.{view_name}",))
        return bool(rows and rows[0].get("reg"))

    def _refresh_view(self, view_name: str) -> None:
        concurrently = bool(self.config.get("dws.mv.refresh_concurrently", False))
        keyword = "CONCURRENTLY " if concurrently else ""
        sql = f"REFRESH MATERIALIZED VIEW {keyword}{self.DWS_SCHEMA}.{view_name}"
        self.db.execute(sql)

    def _get_layer(self, layer_name: Optional[str]) -> Optional[TimeLayer]:
        if not layer_name:
            return None
        name = str(layer_name).upper()
        try:
            return TimeLayer[name]
        except KeyError:
            return None

    def _resolve_layer_map(self, raw: Any) -> Dict[str, str]:
        if not raw:
            return {}
        if isinstance(raw, dict):
            return {str(k): str(v) for k, v in raw.items()}
        if isinstance(raw, str):
            try:
                parsed = json.loads(raw)
                if isinstance(parsed, dict):
                    return {str(k): str(v) for k, v in parsed.items()}
            except json.JSONDecodeError:
                return {}
        return {}

    def _parse_layers(self, raw: Any) -> List[TimeLayer]:
        if not raw:
            return []
        if isinstance(raw, str):
            items = [v.strip() for v in raw.split(",") if v.strip()]
        elif isinstance(raw, (list, tuple, set)):
            items = [str(v).strip() for v in raw if str(v).strip()]
        else:
            return []
        layers = []
        for item in items:
            layer = self._get_layer(item)
            if layer and layer not in layers:
                layers.append(layer)
        return layers

    def _parse_list(self, raw: Any) -> List[str]:
        if not raw:
            return []
        if isinstance(raw, str):
            return [v.strip() for v in raw.split(",") if v.strip()]
        if isinstance(raw, (list, tuple, set)):
            return [str(v).strip() for v in raw if str(v).strip()]
        return []


class DwsMvRefreshFinanceDailyTask(BaseMvRefreshTask):
    BASE_TABLE = "dws_finance_daily_summary"
    DATE_COL = "stat_date"

    def get_task_code(self) -> str:
        return "DWS_MV_REFRESH_FINANCE_DAILY"


class DwsMvRefreshAssistantDailyTask(BaseMvRefreshTask):
    BASE_TABLE = "dws_assistant_daily_detail"
    DATE_COL = "stat_date"

    def get_task_code(self) -> str:
        return "DWS_MV_REFRESH_ASSISTANT_DAILY"


__all__ = ["DwsMvRefreshFinanceDailyTask", "DwsMvRefreshAssistantDailyTask"]