import { Injectable, Logger, NotFoundException } from "@nestjs/common";
import { resolveFanavaranClientKey } from "src/core/config/fanavaran-client.config";
import {
  FANAVARAN_REMOTE_LOOKUPS,
  type FanavaranRemoteLookupDefinition,
  TEJARAT_STATIC_ACCIDENT_FILES,
} from "src/fanavaran/fanavaran-lookup.config";
import { FanavaranLookupService } from "src/fanavaran/fanavaran-lookup.service";
import { LookupDbService } from "./entities/db-service/lookup.db.service";

type TejaratAccidentReasonRow = {
  id: number;
  persianLabel: string;
  fanavaranID: number;
};

type TejaratAccidentLabelRow = {
  id: number;
  persianLabel: string;
};

@Injectable()
export class LookupsService {
  private readonly logger = new Logger(LookupsService.name);

  constructor(
    private readonly lookupDbService: LookupDbService,
    private readonly fanavaranLookupService: FanavaranLookupService,
  ) {}

  private activeClientKey() {
    return resolveFanavaranClientKey();
  }

  listFanavaranRemoteLookups(): FanavaranRemoteLookupDefinition[] {
    return FANAVARAN_REMOTE_LOOKUPS;
  }

  private findRemoteLookup(name: string) {
    const lookup = FANAVARAN_REMOTE_LOOKUPS.find((item) => item.name === name);
    if (!lookup) {
      throw new NotFoundException(`Unknown Fanavaran remote lookup: ${name}`);
    }
    return lookup;
  }

  /**
   * Returns stored `response` for a lookup document by `name` in the lookups collection.
   * Legacy Tejarat seed data — used as fallback when live fetch is unavailable.
   */
  async getLookup(lookupName: string): Promise<any> {
    const doc = await this.lookupDbService.findOne({ name: lookupName });
    if (!doc) {
      this.logger.warn(`Lookup not found in database: ${lookupName}`);
      throw new NotFoundException(`Lookup "${lookupName}" not found`);
    }
    return doc.response;
  }

  async getClientRemoteLookup(lookupName: string): Promise<unknown> {
    const clientKey = this.activeClientKey();
    const definition = this.findRemoteLookup(lookupName);

    return this.fanavaranLookupService.getRemoteLookup(
      clientKey,
      definition.url,
      definition.cacheFile,
      clientKey === "tejaratno"
        ? async () => this.getLookup(lookupName)
        : undefined,
    );
  }

  async getAccidentCauses(): Promise<any> {
    return await this.getClientRemoteLookup("accident-causes");
  }

  async getAccidentReportType(): Promise<any> {
    return await this.getClientRemoteLookup("accident-report-type");
  }

  async getVehicleUseTypes(): Promise<any> {
    return await this.getClientRemoteLookup("vehicle-use-types");
  }

  async getDmgPayMethod(): Promise<any> {
    return await this.getClientRemoteLookup("dmg-pay-method");
  }

  async getDrivingLicenceTypes(): Promise<any> {
    return await this.getClientRemoteLookup("driving-licence-types");
  }

  async getAccidentCulpritType(): Promise<any> {
    return await this.getClientRemoteLookup("accident-culprit-type");
  }

  async getInspectionPlace(): Promise<any> {
    return await this.getClientRemoteLookup("inspection-place");
  }

  async getDropAmountStatus(): Promise<any> {
    return await this.getClientRemoteLookup("drop-amount-status");
  }

  async getCarComponents(): Promise<any> {
    return await this.getClientRemoteLookup("car-components");
  }

  async getAccidentLevel(): Promise<any> {
    return await this.getClientRemoteLookup("accident-level");
  }

  async getExpertStatus(): Promise<any> {
    return await this.getClientRemoteLookup("expert-status");
  }

  async getVehicleKinds(): Promise<any> {
    return await this.getClientRemoteLookup("vehicle-kinds");
  }

  async inquiryByVin(vin: string): Promise<unknown> {
    const clientKey = this.activeClientKey();
    return this.fanavaranLookupService.inquiryByVin(clientKey, vin);
  }

  async getAccidentWay(): Promise<{ id: number; label: string }[]> {
    const clientKey = this.activeClientKey();
    const fileName = TEJARAT_STATIC_ACCIDENT_FILES.accidentWay;

    const cached = await this.fanavaranLookupService.readCacheFile<
      TejaratAccidentLabelRow[]
    >(clientKey, fileName);
    const raw =
      cached ??
      (clientKey === "tejaratno"
        ? await this.fanavaranLookupService.readTejaratStaticAccidentFile<
            TejaratAccidentLabelRow[]
          >(fileName)
        : null);

    if (!raw) {
      this.logger.warn(
        `No accident-way lookup for client ${clientKey}; falling back to tejarat static file`,
      );
      const fallback =
        await this.fanavaranLookupService.readTejaratStaticAccidentFile<
          TejaratAccidentLabelRow[]
        >(fileName);
      return fallback.map((item) => ({
        id: item.id,
        label: item.persianLabel,
      }));
    }

    return raw.map((item) => ({ id: item.id, label: item.persianLabel }));
  }

  async getAccidentReason(): Promise<
    { id: number; label: string; fanavaran: number }[]
  > {
    const clientKey = this.activeClientKey();

    if (clientKey === "parsian") {
      const cacheFile = "accident-reason-options.json";
      const cached = await this.fanavaranLookupService.readCacheFile<
        { id: number; label: string; fanavaran: number }[]
      >(clientKey, cacheFile);
      if (cached) {
        return cached;
      }

      const causes = await this.getAccidentCauses();
      const mapped =
        this.fanavaranLookupService.mapFanavaranAccidentCausesToReasonOptions(
          causes,
        );
      await this.fanavaranLookupService.writeCacheFile(
        clientKey,
        cacheFile,
        mapped,
      );
      return mapped;
    }

    const fileName = TEJARAT_STATIC_ACCIDENT_FILES.accidentReason;
    const cached = await this.fanavaranLookupService.readCacheFile<
      TejaratAccidentReasonRow[]
    >(clientKey, fileName);
    const raw =
      cached ??
      (await this.fanavaranLookupService.readTejaratStaticAccidentFile<
        TejaratAccidentReasonRow[]
      >(fileName));

    return raw.map((item) => ({
      id: item.id,
      label: item.persianLabel,
      fanavaran: item.fanavaranID,
    }));
  }

  async getAccidentType(): Promise<{ id: number; label: string }[]> {
    const clientKey = this.activeClientKey();
    const fileName = TEJARAT_STATIC_ACCIDENT_FILES.accidentType;

    const cached = await this.fanavaranLookupService.readCacheFile<
      TejaratAccidentLabelRow[]
    >(clientKey, fileName);
    const raw =
      cached ??
      (clientKey === "tejaratno"
        ? await this.fanavaranLookupService.readTejaratStaticAccidentFile<
            TejaratAccidentLabelRow[]
          >(fileName)
        : null);

    if (!raw) {
      this.logger.warn(
        `No accident-type lookup for client ${clientKey}; falling back to tejarat static file`,
      );
      const fallback =
        await this.fanavaranLookupService.readTejaratStaticAccidentFile<
          TejaratAccidentLabelRow[]
        >(fileName);
      return fallback.map((item) => ({
        id: item.id,
        label: item.persianLabel,
      }));
    }

    return raw.map((item) => ({ id: item.id, label: item.persianLabel }));
  }

  async getAccidentFields(): Promise<{
    accidentWay: { id: number; label: string }[];
    accidentReason: { id: number; label: string; fanavaran: number }[];
    accidentType: { id: number; label: string }[];
    client: string;
  }> {
    const [accidentWay, accidentReason, accidentType] = await Promise.all([
      this.getAccidentWay(),
      this.getAccidentReason(),
      this.getAccidentType(),
    ]);
    return {
      client: this.activeClientKey(),
      accidentWay,
      accidentReason,
      accidentType,
    };
  }
}