/**
 * Payload Fetch Handler
 *
 * Per TASK_WORKFLOW_2024-12-10.md: Separates API fetch from data processing.
 *
 * This handler ONLY:
 * 1. Hits Dutchie GraphQL API
 * 2. Saves raw payload to filesystem (gzipped)
 * 3. Records metadata in raw_crawl_payloads table
 * 4. Queues a product_refresh task to process the payload
 *
 * Benefits of separation:
 * - Retry-friendly: If normalize fails, re-run refresh without re-crawling
 * - Faster refreshes: Local file read vs network call
 * - Replay-able: Run refresh against any historical payload
 * - Less API pressure: Only this role hits Dutchie
 */

import { TaskContext, TaskResult } from '../task-worker';
import {
  executeGraphQL,
  startSession,
  endSession,
  GRAPHQL_HASHES,
  DUTCHIE_CONFIG,
} from '../../platforms/dutchie';
import { saveRawPayload } from '../../utils/payload-storage';
import { taskService } from '../task-service';

export async function handlePayloadFetch(ctx: TaskContext): Promise<TaskResult> {
  const { pool, task } = ctx;
  const dispensaryId = task.dispensary_id;

  if (!dispensaryId) {
    return { success: false, error: 'No dispensary_id specified for payload_fetch task' };
  }

  try {
    // ============================================================
    // STEP 1: Load dispensary info
    // ============================================================
    const dispResult = await pool.query(`
      SELECT
        id, name, platform_dispensary_id, menu_url, menu_type, city, state
      FROM dispensaries
      WHERE id = $1 AND crawl_enabled = true
    `, [dispensaryId]);

    if (dispResult.rows.length === 0) {
      return { success: false, error: `Dispensary ${dispensaryId} not found or not crawl_enabled` };
    }

    const dispensary = dispResult.rows[0];
    const platformId = dispensary.platform_dispensary_id;

    if (!platformId) {
      return { success: false, error: `Dispensary ${dispensaryId} has no platform_dispensary_id` };
    }

    // Extract cName from menu_url
    const cNameMatch = dispensary.menu_url?.match(/\/(?:embedded-menu|dispensary)\/([^/?]+)/);
    const cName = cNameMatch ? cNameMatch[1] : 'dispensary';

    console.log(`[PayloadFetch] Starting fetch for ${dispensary.name} (ID: ${dispensaryId})`);
    console.log(`[PayloadFetch] Platform ID: ${platformId}, cName: ${cName}`);

    // ============================================================
    // STEP 2: Start stealth session
    // ============================================================
    const session = startSession();
    console.log(`[PayloadFetch] Session started: ${session.sessionId}`);

    await ctx.heartbeat();

    // ============================================================
    // STEP 3: Fetch products via GraphQL (Status: 'All')
    // ============================================================
    const allProducts: any[] = [];
    let page = 0;
    let totalCount = 0;
    const perPage = DUTCHIE_CONFIG.perPage;
    const maxPages = DUTCHIE_CONFIG.maxPages;

    try {
      while (page < maxPages) {
        const variables = {
          includeEnterpriseSpecials: false,
          productsFilter: {
            dispensaryId: platformId,
            pricingType: 'rec',
            Status: 'All',
            types: [],
            useCache: false,
            isDefaultSort: true,
            sortBy: 'popularSortIdx',
            sortDirection: 1,
            bypassOnlineThresholds: true,
            isKioskMenu: false,
            removeProductsBelowOptionThresholds: false,
          },
          page,
          perPage,
        };

        console.log(`[PayloadFetch] Fetching page ${page + 1}...`);

        const result = await executeGraphQL(
          'FilteredProducts',
          variables,
          GRAPHQL_HASHES.FilteredProducts,
          { cName, maxRetries: 3 }
        );

        const data = result?.data?.filteredProducts;
        if (!data || !data.products) {
          if (page === 0) {
            throw new Error('No product data returned from GraphQL');
          }
          break;
        }

        const products = data.products;
        allProducts.push(...products);

        if (page === 0) {
          totalCount = data.queryInfo?.totalCount || products.length;
          console.log(`[PayloadFetch] Total products reported: ${totalCount}`);
        }

        if (allProducts.length >= totalCount || products.length < perPage) {
          break;
        }

        page++;

        if (page < maxPages) {
          await new Promise(r => setTimeout(r, DUTCHIE_CONFIG.pageDelayMs));
        }

        if (page % 5 === 0) {
          await ctx.heartbeat();
        }
      }

      console.log(`[PayloadFetch] Fetched ${allProducts.length} products in ${page + 1} pages`);

    } finally {
      endSession();
    }

    if (allProducts.length === 0) {
      return {
        success: false,
        error: 'No products returned from GraphQL',
        productsProcessed: 0,
      };
    }

    await ctx.heartbeat();

    // ============================================================
    // STEP 4: Save raw payload to filesystem
    // Per TASK_WORKFLOW_2024-12-10.md: Metadata/Payload separation
    // ============================================================
    const rawPayload = {
      dispensaryId,
      platformId,
      cName,
      fetchedAt: new Date().toISOString(),
      productCount: allProducts.length,
      products: allProducts,
    };

    const payloadResult = await saveRawPayload(
      pool,
      dispensaryId,
      rawPayload,
      null, // crawl_run_id - not using crawl_runs in new system
      allProducts.length
    );

    console.log(`[PayloadFetch] Saved payload #${payloadResult.id} (${(payloadResult.sizeBytes / 1024).toFixed(1)}KB)`);

    // ============================================================
    // STEP 5: Update dispensary last_fetch_at
    // ============================================================
    await pool.query(`
      UPDATE dispensaries
      SET last_fetch_at = NOW()
      WHERE id = $1
    `, [dispensaryId]);

    // ============================================================
    // STEP 6: Queue product_refresh task to process the payload
    // Per TASK_WORKFLOW_2024-12-10.md: Task chaining
    // ============================================================
    await taskService.createTask({
      role: 'product_refresh',
      dispensary_id: dispensaryId,
      priority: task.priority || 0,
      payload: { payload_id: payloadResult.id },
    });

    console.log(`[PayloadFetch] Queued product_refresh task for payload #${payloadResult.id}`);

    return {
      success: true,
      payloadId: payloadResult.id,
      productCount: allProducts.length,
      sizeBytes: payloadResult.sizeBytes,
    };

  } catch (error: unknown) {
    const errorMessage = error instanceof Error ? error.message : 'Unknown error';
    console.error(`[PayloadFetch] Error for dispensary ${dispensaryId}:`, errorMessage);
    return {
      success: false,
      error: errorMessage,
    };
  }
}