import crypto from 'crypto';
import { storage } from '../storage';
import { generateBotServiceToken } from '../utils/jwt';
import { sendWebhook } from '../utils/webhook';
import type { BotSubscription } from '@shared/schema';
import { decrypt } from '../crypto';

export interface WebhookEvent {
  event: string;
  timestamp: string;
  organizationId: number;
  data: any;
}

export class WebhookService {
  async dispatchEvent(event: WebhookEvent): Promise<void> {
    const { organizationId, event: eventType, data } = event;

    try {
      let subscriptions: BotSubscription[] = [];

      if (data.formId) {
        const formSubs = await storage.getBotSubscriptionsByForm(data.formId, organizationId);
        subscriptions = [...subscriptions, ...formSubs.filter(s => (s.events as string[]).includes(eventType))];
      }

      if (data.statusId) {
        const statusSubs = await storage.getBotSubscriptionsByStatus(data.statusId, organizationId);
        subscriptions = [...subscriptions, ...statusSubs.filter(s => (s.events as string[]).includes(eventType))];
      }

      if (data.transitionId) {
        const transitionSubs = await storage.getBotSubscriptionsByTransition(data.transitionId, organizationId);
        subscriptions = [...subscriptions, ...transitionSubs.filter(s => (s.events as string[]).includes(eventType))];
      }

      const uniqueBotIds = Array.from(new Set(subscriptions.map(s => s.botId)));

      for (const botId of uniqueBotIds) {
        const bot = await storage.getBot(botId, organizationId);
        if (!bot || !bot.webhookUrl || !bot.webhookEnabled || !bot.isActive) {
          continue;
        }

        // Generate short-lived access token for the bot
        const botAccessToken = generateBotServiceToken(bot.id, organizationId);

        const payload = {
          ...event,
          bot: {
            id: bot.id,
            name: bot.name,
            accessToken: botAccessToken // Short-lived token (10 min) for API callbacks
          }
        };

        let signature = '';
        if (bot.webhookSecret) {
          const secret = decrypt(bot.webhookSecret);
          signature = crypto
            .createHmac('sha256', secret)
            .update(JSON.stringify(payload))
            .digest('hex');
        }

        await sendWebhook(
          bot.webhookUrl,
          payload,
          {
            'X-Webhook-Signature': signature,
            'X-Bot-Id': bot.id.toString(),
            'X-Event-Type': eventType,
          },
          {
            taskId: data.taskId,
            organizationId,
            botId: bot.id,
            eventType,
          }
        );
      }
    } catch (error) {
      console.error('Webhook dispatch error:', error);
    }
  }

  async dispatchStatusChange(
    organizationId: number, 
    taskId: number, 
    formId: number,
    fromStatusId: number,
    toStatusId: number,
    transitionId: number,
    userId: number
  ): Promise<void> {
    const task = await storage.getTask(taskId, organizationId);
    const user = await storage.getUser(userId);
    
    await this.dispatchEvent({
      event: 'status_change',
      timestamp: new Date().toISOString(),
      organizationId,
      data: {
        taskId,
        formId,
        task,
        fromStatusId,
        toStatusId,
        transitionId,
        statusId: toStatusId,
        user: user ? {
          id: user.id,
          firstName: user.firstName,
          lastName: user.lastName,
          email: user.email
        } : null
      }
    });
  }

  async dispatchComment(
    organizationId: number,
    taskId: number,
    formId: number,
    message: any,
    authorId: number
  ): Promise<void> {
    const task = await storage.getTask(taskId, organizationId);
    const author = await storage.getUser(authorId);

    await this.dispatchEvent({
      event: 'comment',
      timestamp: new Date().toISOString(),
      organizationId,
      data: {
        taskId,
        formId,
        task,
        message,
        author: author ? {
          id: author.id,
          firstName: author.firstName,
          lastName: author.lastName,
          email: author.email
        } : null
      }
    });
  }

  async dispatchFieldChange(
    organizationId: number,
    taskId: number,
    formId: number,
    fieldId: number,
    fieldCode: string,
    oldValue: any,
    newValue: any,
    userId: number
  ): Promise<void> {
    const task = await storage.getTask(taskId, organizationId);
    const user = await storage.getUser(userId);

    await this.dispatchEvent({
      event: 'field_change',
      timestamp: new Date().toISOString(),
      organizationId,
      data: {
        taskId,
        formId,
        task,
        fieldId,
        fieldCode,
        oldValue,
        newValue,
        user: user ? {
          id: user.id,
          firstName: user.firstName,
          lastName: user.lastName,
          email: user.email
        } : null
      }
    });
  }
}

export const webhookService = new WebhookService();