import { Provide } from "@midwayjs/core";
import { InjectRepository } from "@midwayjs/sequelize";
import { Repository } from "sequelize-typescript";
import { Op } from "sequelize";
import { Context } from "@midwayjs/koa";
import ElectricLine from "../entity/electric_line.entity";
import IccSyncLog from "../entity/icc_sync_log.entity";
import Customer from "../entity/customer.entity";
import CustomerEquipment from "../entity/customer_equipment.entity";
import CustomerBuilding from "../entity/customer_building.entity";
import { ICC_LINE_ENDPOINT, mapIccLineRecord, IccLineRawRecord } from "../task/icc_line_mapper";

export interface IccLineSyncResult {
	/** ICC 拉取到的原始条数 */
	pulled: number;
	/** 解析落库的线路条数（成功 upsert，含新增/更新） */
	synced: number;
	/** 新增的线路条数 */
	inserted: number;
	/** 更新的线路条数 */
	updated: number;
	/** 因缺少合法 line_code 或无法匹配客户/设备而跳过的条数 */
	skipped: number;
}

const SYNC_TYPE = "electric_line";

/**
 * ICC 智电改造线路拉取同步：
 *  1) 从 .env 读取 ICC_BASE_URL / ICC_TOKEN 占位配置
 *  2) 请求 ICC 线路列表（路径与字段映射集中在 icc_line_mapper）
 *  3) 按 line_code 幂等 upsert 写入 electric_line，更新 synced_at
 *  4) 每次同步写一条 icc_sync_log；ICC 拉取失败仅记录 error，不抛业务错误
 */
@Provide()
export class IccLineSyncService {
	@InjectRepository(ElectricLine)
	lineModel!: Repository<ElectricLine>;

	@InjectRepository(IccSyncLog)
	syncLogModel!: Repository<IccSyncLog>;

	@InjectRepository(Customer)
	customerModel!: Repository<Customer>;

	@InjectRepository(CustomerEquipment)
	equipmentModel!: Repository<CustomerEquipment>;

	@InjectRepository(CustomerBuilding)
	buildingModel!: Repository<CustomerBuilding>;

	async syncFromIcc(ctx?: Context): Promise<IccLineSyncResult> {
		const startTime = new Date();
		const baseUrl = process.env.ICC_BASE_URL?.trim();
		const token = process.env.ICC_TOKEN?.trim();

		const result: IccLineSyncResult = { pulled: 0, synced: 0, inserted: 0, updated: 0, skipped: 0 };

		// 占位配置缺失视为拉取失败：记录日志，不抛业务错误
		if (!baseUrl) {
			await this.writeLog(startTime, 0, SYNC_TYPE, 0, "未配置 ICC_BASE_URL，请检查 server/.env");
			return result;
		}

		try {
			const url = `${baseUrl.replace(/\/$/, "")}${ICC_LINE_ENDPOINT}`;
			const headers: Record<string, string> = { Accept: "application/json" };
			if (token) headers.Authorization = `Bearer ${token}`;

			const res = await fetch(url, {
				method: "GET",
				headers,
				signal: AbortSignal.timeout(60000) // 按项目约定 HTTP 超时 60s
			});

			if (!res.ok) {
				throw new Error(`ICC 线路接口返回异常：HTTP ${res.status}`);
			}

			const payload: any = await res.json();
			// 兼容缓存工具包裹(data/list 字段)返回格式
			const rawList: IccLineRawRecord[] = Array.isArray(payload)
				? payload
				: Array.isArray(payload.data)
				? payload.data
				: Array.isArray(payload.list)
				? payload.list
				: [];
			result.pulled = rawList.length;

			const { inserted, updated, skipped } = await this.batchUpsert(rawList);
			result.inserted = inserted;
			result.updated = updated;
			result.synced = inserted + updated;
			result.skipped = skipped;

			await this.writeLog(startTime, 1, SYNC_TYPE, result.synced, null);
			return result;
		} catch (err: any) {
			const message = err?.code === "ERR_MODULE_NOT_FOUND" || err?.message
				? String(err?.message || err)
				: String(err);
			await this.writeLog(startTime, 0, SYNC_TYPE, result.pulled, message);
			return result;
		}
	}

	/** 批量按 line_code upsert（幂等），并做客户/设备/建筑外键反查。 */
	private async batchUpsert(records: IccLineRawRecord[]): Promise<{ inserted: number; updated: number; skipped: number }> {
		let inserted = 0;
		let updated = 0;
		let skipped = 0;

		if (records.length === 0) return { inserted, updated, skipped };

		// 预取外键映射，避免 N+1
		const equipCodes = [...new Set(records.map((r) => mapIccLineRecord(r).equipCode).filter(Boolean))];
		const customerNos = [...new Set(records.map((r) => mapIccLineRecord(r).customerNo).filter(Boolean))];
		const buildingNames = [...new Set(records.map((r) => mapIccLineRecord(r).buildingName).filter(Boolean))];

		const [equips, customers, buildings] = await Promise.all([
			equipCodes.length
				? this.equipmentModel.findAll({ where: { equipCode: { [Op.in]: equipCodes } }, attributes: ["id", "equipCode", "customerId", "buildingId"] })
				: Promise.resolve([]),
			customerNos.length
				? this.customerModel.findAll({ where: { customerNo: { [Op.in]: customerNos } }, attributes: ["id", "customerNo"] })
				: Promise.resolve([]),
			buildingNames.length
				? this.buildingModel.findAll({ where: { buildingName: { [Op.in]: buildingNames } }, attributes: ["id", "buildingName", "customerId"] })
				: Promise.resolve([])
		]);

		const equipByCode = new Map(equips.map((e) => [e.equipCode, e]));
		const customerByNo = new Map(customers.map((c) => [c.customerNo, c]));
		const buildingByName = new Map(buildings.map((b) => [b.buildingName, b]));

		const now = new Date();

		for (const raw of records) {
			const mapped = mapIccLineRecord(raw);
			if (!mapped.lineCode) {
				skipped++;
				continue;
			}

			const equip = mapped.equipCode ? equipByCode.get(mapped.equipCode) : undefined;
			// equip_id 与 customer_id 为 NOT NULL，无法解析时跳过该行
			if (!equip) {
				skipped++;
				continue;
			}

			let customerId: number = equip.customerId;
			if (mapped.customerNo) {
				const byNo = customerByNo.get(mapped.customerNo);
				if (byNo) customerId = byNo.id;
			}

			let buildingId: number | null = equip.buildingId || null;
			if (mapped.buildingName) {
				const building = buildingByName.get(mapped.buildingName);
				if (building) buildingId = building.id;
			}

			const payload = {
				lineCode: mapped.lineCode,
				equipId: equip.id,
				customerId,
				buildingId,
				iccDeviceCode: mapped.iccDeviceCode || null,
				lineName: mapped.lineName || null,
				floorNo: mapped.floorNo || null,
				location: mapped.location || null,
				status: mapped.status,
				syncedAt: now
			} as any;

			const existing = await this.lineModel.findOne({ where: { lineCode: mapped.lineCode } });
			if (existing) {
				await existing.update(payload);
				updated++;
			} else {
				await this.lineModel.create(payload);
				inserted++;
			}
		}

		return { inserted, updated, skipped };
	}

	private async writeLog(startTime: Date, status: number, syncType: string, recordCount: number, errorMessage: string | null): Promise<void> {
		try {
			await this.syncLogModel.create({
				syncType,
				startTime,
				endTime: new Date(),
				recordCount,
				status,
				errorMessage
			} as any);
		} catch (err) {
			console.error("[ICC同步] 同步日志写入失败:", err);
		}
	}
}