/**
 * CanonicalHydrationService
 * Orchestrates the full hydration pipeline from dutchie_* to canonical tables
 */

import { Pool } from 'pg';
import { CrawlRunRecorder } from './crawl-run-recorder';
import { StoreProductNormalizer } from './store-product-normalizer';
import { SnapshotWriter } from './snapshot-writer';
import { HydrationOptions, HydrationResult, ServiceContext, SourceJob } from './types';

export class CanonicalHydrationService {
  private pool: Pool;
  private log: (message: string) => void;
  private crawlRunRecorder: CrawlRunRecorder;
  private productNormalizer: StoreProductNormalizer;
  private snapshotWriter: SnapshotWriter;

  constructor(ctx: ServiceContext) {
    this.pool = ctx.pool;
    this.log = ctx.logger || console.log;
    this.crawlRunRecorder = new CrawlRunRecorder(ctx);
    this.productNormalizer = new StoreProductNormalizer(ctx);
    this.snapshotWriter = new SnapshotWriter(ctx);
  }

  /**
   * Run the full hydration pipeline
   * Supports both backfill (historical) and incremental (ongoing) modes
   */
  async hydrate(options: HydrationOptions): Promise<HydrationResult> {
    const startTime = Date.now();
    const result: HydrationResult = {
      crawlRunsCreated: 0,
      crawlRunsSkipped: 0,
      productsUpserted: 0,
      snapshotsWritten: 0,
      errors: [],
      durationMs: 0,
    };

    this.log(`Starting hydration in ${options.mode} mode`);

    try {
      if (options.mode === 'backfill') {
        await this.runBackfill(options, result);
      } else {
        await this.runIncremental(options, result);
      }
    } catch (err: any) {
      result.errors.push(`Fatal error: ${err.message}`);
      this.log(`Hydration failed: ${err.message}`);
    }

    result.durationMs = Date.now() - startTime;
    this.log(`Hydration completed in ${result.durationMs}ms: ${JSON.stringify({
      crawlRunsCreated: result.crawlRunsCreated,
      crawlRunsSkipped: result.crawlRunsSkipped,
      productsUpserted: result.productsUpserted,
      snapshotsWritten: result.snapshotsWritten,
      errors: result.errors.length,
    })}`);

    return result;
  }

  /**
   * Backfill mode: Process historical data from source tables
   */
  private async runBackfill(options: HydrationOptions, result: HydrationResult): Promise<void> {
    const batchSize = options.batchSize || 50;

    // Get source jobs to process
    const sourceJobs = await this.crawlRunRecorder.getSourceJobsForBackfill(
      options.startDate,
      options.endDate,
      options.dispensaryId,
      1000 // Max jobs to process
    );

    this.log(`Found ${sourceJobs.length} source jobs to backfill`);

    // Group jobs by dispensary for efficient processing
    const jobsByDispensary = this.groupJobsByDispensary(sourceJobs);

    for (const [dispensaryId, jobs] of jobsByDispensary) {
      this.log(`Processing dispensary ${dispensaryId} (${jobs.length} jobs)`);

      try {
        // Step 1: Upsert products for this dispensary
        if (!options.dryRun) {
          const productResult = await this.productNormalizer.upsertProductsForDispensary(dispensaryId);
          result.productsUpserted += productResult.upserted;
          if (productResult.errors.length > 0) {
            result.errors.push(...productResult.errors.map(e => `Dispensary ${dispensaryId}: ${e}`));
          }
        }

        // Get store_product_id map for snapshot writing
        const storeProductIdMap = await this.productNormalizer.getStoreProductIdMap(dispensaryId);

        // Step 2: Record crawl runs and write snapshots for each job
        for (const job of jobs) {
          try {
            await this.processJob(job, storeProductIdMap, result, options.dryRun);
          } catch (err: any) {
            result.errors.push(`Job ${job.id}: ${err.message}`);
          }
        }
      } catch (err: any) {
        result.errors.push(`Dispensary ${dispensaryId}: ${err.message}`);
      }
    }
  }

  /**
   * Incremental mode: Process only unhydrated jobs
   */
  private async runIncremental(options: HydrationOptions, result: HydrationResult): Promise<void> {
    const limit = options.batchSize || 100;

    // Get unhydrated jobs
    const unhydratedJobs = await this.crawlRunRecorder.getUnhydratedJobs(
      options.dispensaryId,
      options.startDate,
      limit
    );

    this.log(`Found ${unhydratedJobs.length} unhydrated jobs`);

    // Group by dispensary
    const jobsByDispensary = this.groupJobsByDispensary(unhydratedJobs);

    for (const [dispensaryId, jobs] of jobsByDispensary) {
      this.log(`Processing dispensary ${dispensaryId} (${jobs.length} jobs)`);

      try {
        // Step 1: Upsert products
        if (!options.dryRun) {
          const productResult = await this.productNormalizer.upsertProductsForDispensary(dispensaryId);
          result.productsUpserted += productResult.upserted;
          if (productResult.errors.length > 0) {
            result.errors.push(...productResult.errors.map(e => `Dispensary ${dispensaryId}: ${e}`));
          }
        }

        // Get store_product_id map
        const storeProductIdMap = await this.productNormalizer.getStoreProductIdMap(dispensaryId);

        // Step 2: Process each job
        for (const job of jobs) {
          try {
            await this.processJob(job, storeProductIdMap, result, options.dryRun);
          } catch (err: any) {
            result.errors.push(`Job ${job.id}: ${err.message}`);
          }
        }
      } catch (err: any) {
        result.errors.push(`Dispensary ${dispensaryId}: ${err.message}`);
      }
    }
  }

  /**
   * Process a single job: record crawl run and write snapshots
   */
  private async processJob(
    job: SourceJob,
    storeProductIdMap: Map<string, number>,
    result: HydrationResult,
    dryRun?: boolean
  ): Promise<void> {
    // Step 1: Record the crawl run
    let crawlRunId: number | null = null;

    if (!dryRun) {
      crawlRunId = await this.crawlRunRecorder.recordCrawlRun(job);
      if (crawlRunId) {
        result.crawlRunsCreated++;
      } else {
        result.crawlRunsSkipped++;
        return; // Skip snapshot writing if crawl run wasn't created
      }
    } else {
      // In dry run, check if it would be created
      const existingId = await this.crawlRunRecorder.getCrawlRunIdBySourceJob(
        'dispensary_crawl_jobs',
        job.id
      );
      if (existingId) {
        result.crawlRunsSkipped++;
        return;
      }
      result.crawlRunsCreated++;
      return; // Skip snapshot writing in dry run
    }

    // Step 2: Write snapshots for this crawl run
    if (crawlRunId && job.completed_at) {
      const snapshotResult = await this.snapshotWriter.writeSnapshotsForCrawlRun(
        crawlRunId,
        job.dispensary_id,
        storeProductIdMap,
        job.completed_at
      );

      result.snapshotsWritten += snapshotResult.written;
      if (snapshotResult.errors.length > 0) {
        result.errors.push(...snapshotResult.errors);
      }

      // Update crawl_run with snapshots_written count
      await this.crawlRunRecorder.updateSnapshotsWritten(crawlRunId, snapshotResult.written);
    }
  }

  /**
   * Hydrate a single dispensary (convenience method)
   */
  async hydrateDispensary(
    dispensaryId: number,
    mode: 'backfill' | 'incremental' = 'incremental'
  ): Promise<HydrationResult> {
    return this.hydrate({
      mode,
      dispensaryId,
    });
  }

  /**
   * Get hydration status for a dispensary
   */
  async getHydrationStatus(dispensaryId: number): Promise<{
    sourceJobs: number;
    hydratedJobs: number;
    unhydratedJobs: number;
    sourceProducts: number;
    storeProducts: number;
    sourceSnapshots: number;
    storeSnapshots: number;
  }> {
    const [sourceJobs, hydratedJobs, sourceProducts, storeProducts, sourceSnapshots, storeSnapshots] =
      await Promise.all([
        this.pool.query(
          `SELECT COUNT(*) FROM dispensary_crawl_jobs
           WHERE dispensary_id = $1 AND status = 'completed' AND job_type = 'dutchie_product_crawl'`,
          [dispensaryId]
        ),
        this.pool.query(
          `SELECT COUNT(*) FROM crawl_runs
           WHERE dispensary_id = $1 AND source_job_type = 'dispensary_crawl_jobs'`,
          [dispensaryId]
        ),
        this.pool.query(
          `SELECT COUNT(*) FROM dutchie_products WHERE dispensary_id = $1`,
          [dispensaryId]
        ),
        this.pool.query(
          `SELECT COUNT(*) FROM store_products WHERE dispensary_id = $1 AND provider = 'dutchie'`,
          [dispensaryId]
        ),
        this.pool.query(
          `SELECT COUNT(*) FROM dutchie_product_snapshots WHERE dispensary_id = $1`,
          [dispensaryId]
        ),
        this.pool.query(
          `SELECT COUNT(*) FROM store_product_snapshots WHERE dispensary_id = $1`,
          [dispensaryId]
        ),
      ]);

    const sourceJobCount = parseInt(sourceJobs.rows[0].count);
    const hydratedJobCount = parseInt(hydratedJobs.rows[0].count);

    return {
      sourceJobs: sourceJobCount,
      hydratedJobs: hydratedJobCount,
      unhydratedJobs: sourceJobCount - hydratedJobCount,
      sourceProducts: parseInt(sourceProducts.rows[0].count),
      storeProducts: parseInt(storeProducts.rows[0].count),
      sourceSnapshots: parseInt(sourceSnapshots.rows[0].count),
      storeSnapshots: parseInt(storeSnapshots.rows[0].count),
    };
  }

  /**
   * Get overall hydration status
   */
  async getOverallStatus(): Promise<{
    totalSourceJobs: number;
    totalHydratedJobs: number;
    totalSourceProducts: number;
    totalStoreProducts: number;
    totalSourceSnapshots: number;
    totalStoreSnapshots: number;
    dispensariesWithData: number;
  }> {
    const [sourceJobs, hydratedJobs, sourceProducts, storeProducts, sourceSnapshots, storeSnapshots, dispensaries] =
      await Promise.all([
        this.pool.query(
          `SELECT COUNT(*) FROM dispensary_crawl_jobs
           WHERE status = 'completed' AND job_type = 'dutchie_product_crawl'`
        ),
        this.pool.query(
          `SELECT COUNT(*) FROM crawl_runs WHERE source_job_type = 'dispensary_crawl_jobs'`
        ),
        this.pool.query(`SELECT COUNT(*) FROM dutchie_products`),
        this.pool.query(`SELECT COUNT(*) FROM store_products WHERE provider = 'dutchie'`),
        this.pool.query(`SELECT COUNT(*) FROM dutchie_product_snapshots`),
        this.pool.query(`SELECT COUNT(*) FROM store_product_snapshots`),
        this.pool.query(
          `SELECT COUNT(DISTINCT dispensary_id) FROM dutchie_products`
        ),
      ]);

    return {
      totalSourceJobs: parseInt(sourceJobs.rows[0].count),
      totalHydratedJobs: parseInt(hydratedJobs.rows[0].count),
      totalSourceProducts: parseInt(sourceProducts.rows[0].count),
      totalStoreProducts: parseInt(storeProducts.rows[0].count),
      totalSourceSnapshots: parseInt(sourceSnapshots.rows[0].count),
      totalStoreSnapshots: parseInt(storeSnapshots.rows[0].count),
      dispensariesWithData: parseInt(dispensaries.rows[0].count),
    };
  }

  /**
   * Group jobs by dispensary ID
   */
  private groupJobsByDispensary(jobs: SourceJob[]): Map<number, SourceJob[]> {
    const map = new Map<number, SourceJob[]>();
    for (const job of jobs) {
      const list = map.get(job.dispensary_id) || [];
      list.push(job);
      map.set(job.dispensary_id, list);
    }
    return map;
  }

  /**
   * Products-only hydration mode
   * Used when there are no historical job records - creates synthetic crawl runs
   * from current product data
   */
  async hydrateProductsOnly(options: {
    dispensaryId?: number;
    dryRun?: boolean;
  } = {}): Promise<HydrationResult> {
    const startTime = Date.now();
    const result: HydrationResult = {
      crawlRunsCreated: 0,
      crawlRunsSkipped: 0,
      productsUpserted: 0,
      snapshotsWritten: 0,
      errors: [],
      durationMs: 0,
    };

    this.log('Starting products-only hydration mode');

    try {
      // Get all dispensaries with products
      let dispensaryIds: number[];
      if (options.dispensaryId) {
        dispensaryIds = [options.dispensaryId];
      } else {
        const dispResult = await this.pool.query(
          'SELECT DISTINCT dispensary_id FROM dutchie_products ORDER BY dispensary_id'
        );
        dispensaryIds = dispResult.rows.map(r => r.dispensary_id);
      }

      this.log(`Processing ${dispensaryIds.length} dispensaries`);

      for (const dispensaryId of dispensaryIds) {
        try {
          await this.hydrateDispensaryProductsOnly(dispensaryId, result, options.dryRun);
        } catch (err: any) {
          result.errors.push(`Dispensary ${dispensaryId}: ${err.message}`);
        }
      }
    } catch (err: any) {
      result.errors.push(`Fatal error: ${err.message}`);
    }

    result.durationMs = Date.now() - startTime;
    this.log(`Products-only hydration completed in ${result.durationMs}ms: ${JSON.stringify({
      crawlRunsCreated: result.crawlRunsCreated,
      productsUpserted: result.productsUpserted,
      snapshotsWritten: result.snapshotsWritten,
      errors: result.errors.length,
    })}`);

    return result;
  }

  /**
   * Hydrate a single dispensary in products-only mode
   */
  private async hydrateDispensaryProductsOnly(
    dispensaryId: number,
    result: HydrationResult,
    dryRun?: boolean
  ): Promise<void> {
    // Get product count and timestamps for this dispensary
    const statsResult = await this.pool.query(
      `SELECT COUNT(*) as cnt, MIN(created_at) as min_date, MAX(updated_at) as max_date
       FROM dutchie_products WHERE dispensary_id = $1`,
      [dispensaryId]
    );
    const stats = statsResult.rows[0];
    const productCount = parseInt(stats.cnt);

    if (productCount === 0) {
      this.log(`Dispensary ${dispensaryId}: No products, skipping`);
      return;
    }

    this.log(`Dispensary ${dispensaryId}: ${productCount} products`);

    // Step 1: Create synthetic crawl run
    let crawlRunId: number | null = null;
    const now = new Date();

    if (!dryRun) {
      // Check if we already have a synthetic run for this dispensary
      const existingRun = await this.pool.query(
        `SELECT id FROM crawl_runs
         WHERE dispensary_id = $1
           AND source_job_type = 'products_only_hydration'
         LIMIT 1`,
        [dispensaryId]
      );

      if (existingRun.rows.length > 0) {
        crawlRunId = existingRun.rows[0].id;
        this.log(`Dispensary ${dispensaryId}: Using existing synthetic crawl run ${crawlRunId}`);
        result.crawlRunsSkipped++;
      } else {
        // Create new synthetic crawl run
        const insertResult = await this.pool.query(
          `INSERT INTO crawl_runs (
            dispensary_id, provider, started_at, finished_at, duration_ms,
            status, products_found, trigger_type, metadata,
            source_job_type, source_job_id
          ) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11)
          RETURNING id`,
          [
            dispensaryId,
            'dutchie',
            stats.min_date || now,
            stats.max_date || now,
            0,
            'success',
            productCount,
            'hydration',
            JSON.stringify({ mode: 'products_only', hydratedAt: now.toISOString() }),
            'products_only_hydration',
            dispensaryId, // Use dispensary_id as synthetic job_id
          ]
        );
        crawlRunId = insertResult.rows[0].id;
        result.crawlRunsCreated++;
        this.log(`Dispensary ${dispensaryId}: Created synthetic crawl run ${crawlRunId}`);
      }

      // Step 2: Upsert products
      const productResult = await this.productNormalizer.upsertProductsForDispensary(dispensaryId);
      result.productsUpserted += productResult.upserted;
      if (productResult.errors.length > 0) {
        result.errors.push(...productResult.errors.map(e => `Dispensary ${dispensaryId}: ${e}`));
      }

      // Step 3: Create initial snapshots from current product state
      // crawlRunId is guaranteed to be set at this point (either from existing run or insert)
      const snapshotsWritten = await this.createInitialSnapshots(dispensaryId, crawlRunId!);
      result.snapshotsWritten += snapshotsWritten;

      // Update crawl run with snapshot count
      await this.pool.query(
        'UPDATE crawl_runs SET snapshots_written = $1 WHERE id = $2',
        [snapshotsWritten, crawlRunId]
      );
    } else {
      // Dry run - just count what would be done
      result.crawlRunsCreated++;
      result.productsUpserted += productCount;
      result.snapshotsWritten += productCount;
    }
  }

  /**
   * Create initial snapshots from current product state
   */
  private async createInitialSnapshots(
    dispensaryId: number,
    crawlRunId: number
  ): Promise<number> {
    // Get all store products for this dispensary
    const products = await this.pool.query(
      `SELECT sp.id, sp.price_rec, sp.price_med, sp.is_on_special, sp.is_in_stock,
              sp.stock_quantity, sp.thc_percent, sp.cbd_percent
       FROM store_products sp
       WHERE sp.dispensary_id = $1 AND sp.provider = 'dutchie'`,
      [dispensaryId]
    );

    if (products.rows.length === 0) return 0;

    const now = new Date();
    const batchSize = 100;
    let totalInserted = 0;

    // Process in batches
    for (let i = 0; i < products.rows.length; i += batchSize) {
      const batch = products.rows.slice(i, i + batchSize);
      const values: any[] = [];
      const placeholders: string[] = [];
      let paramIndex = 1;

      for (const product of batch) {
        values.push(
          dispensaryId,
          product.id,
          crawlRunId,
          now,
          product.price_rec,
          product.price_med,
          product.is_on_special || false,
          product.is_in_stock || false,
          product.stock_quantity,
          product.thc_percent,
          product.cbd_percent,
          JSON.stringify({ source: 'initial_hydration' })
        );

        const rowPlaceholders = [];
        for (let j = 0; j < 12; j++) {
          rowPlaceholders.push(`$${paramIndex++}`);
        }
        placeholders.push(`(${rowPlaceholders.join(', ')}, NOW())`);
      }

      const query = `
        INSERT INTO store_product_snapshots (
          dispensary_id, store_product_id, crawl_run_id, captured_at,
          price_rec, price_med, is_on_special, is_in_stock, stock_quantity,
          thc_percent, cbd_percent, raw_data, created_at
        ) VALUES ${placeholders.join(', ')}
        ON CONFLICT (store_product_id, crawl_run_id)
        WHERE store_product_id IS NOT NULL AND crawl_run_id IS NOT NULL
        DO NOTHING
      `;

      const result = await this.pool.query(query, values);
      totalInserted += result.rowCount || 0;
    }

    return totalInserted;
  }
}