Build Call Routing

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import type { VoiceFunction, FunctionContext } from '@sinch/functions-runtime';
import type { Voice } from '@sinch/voice';
import { createIceBuilder, createUniversalConfig } from '@sinch/functions-runtime';

function isBusinessHours(timezone = 'America/New_York'): boolean {
  const now = new Date();
  const local = new Date(now.toLocaleString('en-US', { timeZone: timezone }));
  const day = local.getDay();
  const hour = local.getHours();
  return day >= 1 && day <= 5 && hour >= 9 && hour < 17;
}

export default {
  async ice(context: FunctionContext, event: Voice.IceRequest) {
    const config = createUniversalConfig(context);
    const officeNumber = config.requireVariable('OFFICE_NUMBER');
    const voicemailNumber = config.requireVariable('VOICEMAIL_NUMBER');

    if (isBusinessHours()) {
      return createIceBuilder()
        .say('Connecting you to our team.')
        .connectPstn(officeNumber)
        .build();
    } else {
      return createIceBuilder()
        .say(
          'Our office is currently closed. We are open Monday through Friday, 9 AM to 5 PM Eastern.'
        )
        .connectPstn(voicemailNumber)
        .build();
    }
  },
} satisfies VoiceFunction;

const VIP_LIST = new Set(['+15550001111', '+15550002222']);
const BLOCKED_LIST = new Set(['+19990001111']);

export default {
  async ice(context: FunctionContext, event: Voice.IceRequest) {
    const caller = event.cli ?? '';

    if (BLOCKED_LIST.has(caller)) {
      return createIceBuilder().say('We are unable to take your call. Goodbye.').hangup().build();
    }

    if (VIP_LIST.has(caller)) {
      return createIceBuilder()
        .say('Welcome. Connecting you to our priority line.')
        .connectPstn('+15551110010', { cli: caller })
        .build();
    }

    return createIceBuilder()
      .say('Thank you for calling. Connecting you now.')
      .connectPstn('+15551110001')
      .build();
  },
} satisfies VoiceFunction;

function getRegion(number: string): 'us' | 'uk' | 'eu' | 'default' {
  if (number.startsWith('+1')) return 'us';
  if (number.startsWith('+44')) return 'uk';
  if (number.startsWith('+3') || number.startsWith('+4')) return 'eu';
  return 'default';
}

const REGIONAL_NUMBERS: Record<string, string> = {
  us: '+15551110001',
  uk: '+441110000001',
  eu: '+33110000001',
  default: '+15551110001',
};

export default {
  async ice(context: FunctionContext, event: Voice.IceRequest) {
    const region = getRegion(event.cli ?? '');
    return createIceBuilder()
      .say('Connecting you to your regional support team.')
      .connectPstn(REGIONAL_NUMBERS[region])
      .build();
  },
} satisfies VoiceFunction;

return createIceBuilder()
  .connectPstn('+15551234567', {
    cli: '+15550000000', // Caller ID shown to recipient
    maxDuration: 3600, // Max call length in seconds
    timeout: 30, // Ring timeout
    enableAce: true, // Receive ACE callback when answered
    enablePie: true, // Receive PIE callback for DTMF
    enableDice: true, // Receive DICE callback on disconnect
    indications: 'us', // Ring tone country
  })
  .build();

return createIceBuilder()
  .say('Connecting via SIP.')
  .connectSip('sip:support@pbx.example.com', {
    cli: event.cli,
    headers: { 'X-Custom-Header': 'value' },
  })
  .build();

export default {
  async ice(context: FunctionContext, event: Voice.IceRequest) {
    return createIceBuilder()
      .connectPstn('+15551110001', { enableAce: true, enableDice: true, timeout: 20 })
      .build();
  },

  async dice(context: FunctionContext, event: Voice.DiceRequest) {
    if (event.reason === 'noAnswer' || event.reason === 'busy') {
      // DICE fires after disconnect — re-routing is not possible here.
      // Use an IVR menu or park action for active fallback.
      console.warn('Primary destination did not answer:', event.reason);
    }
  },
} satisfies VoiceFunction;