/**
 * SMS message templates with dynamic variable interpolation.
 *
 * SMS messages avoid markdown (no *bold*) and rich emojis to keep
 * carrier compatibility and minimise character count (1 SMS = 160 chars
 * GSM-7, 70 chars UCS-2). Templates are kept short by design.
 *
 * Variables disponibles :
 *   {{nom}}      – Nom du patient
 *   {{ticket}}   – Numéro de ticket
 *   {{position}} – Position dans la file
 *   {{attente}}  – Temps d'attente estimé (en minutes)
 *   {{cabinet}}  – Nom du cabinet
 */

import {
  type TemplateContext,
  type TemplateType,
  interpolateTemplate,
} from "./whatsappTemplates.js";

export type { TemplateContext, TemplateType };

// ─── Default SMS templates (French, plain-text, short) ───────────────────────

export const DEFAULT_SMS_TEMPLATES: Record<TemplateType, string> = {
  joined:
    `QueueMed - {{cabinet}}\n` +
    `Ticket {{ticket}} | Position {{position}} | ~{{attente}}min\n` +
    `Restez a proximite, vous serez prevenu(e) avant votre tour.`,

  soon:
    `QueueMed - {{cabinet}}\n` +
    `Votre tour approche! Ticket {{ticket}}, ~{{attente}}min.\n` +
    `Merci de venir en salle d'attente maintenant.`,

  called:
    `QueueMed - {{cabinet}}\n` +
    `C'est votre tour! Ticket {{ticket}}.\n` +
    `Veuillez vous presenter au cabinet.`,

  withdrawn:
    `QueueMed - {{cabinet}}\n` +
    `Desistement enregistre. Ticket {{ticket}} annule. A bientot!`,
};

/**
 * Get the effective SMS template: custom if set, otherwise default.
 */
export function getEffectiveSmsTemplate(
  type: TemplateType,
  customTemplates?: Partial<Record<TemplateType, string | null>>
): string {
  const custom = customTemplates?.[type];
  if (custom && custom.trim().length > 0) return custom;
  return DEFAULT_SMS_TEMPLATES[type];
}

/**
 * Build a final SMS message with template + interpolated variables.
 */
export function buildSmsMessage(
  type: TemplateType,
  context: TemplateContext,
  customTemplates?: Partial<Record<TemplateType, string | null>>
): string {
  const template = getEffectiveSmsTemplate(type, customTemplates);
  return interpolateTemplate(template, context);
}

export function buildSmsJoinMessage(
  clinicName: string,
  ticketNumber: number,
  position: number,
  estimatedWait: number
): string {
  return buildSmsMessage("joined", {
    nom: "",
    ticket: ticketNumber,
    position,
    attente: estimatedWait,
    cabinet: clinicName,
  });
}

export function buildSmsSoonMessage(
  clinicName: string,
  ticketNumber: number,
  minutesLeft: number
): string {
  return buildSmsMessage("soon", {
    nom: "",
    ticket: ticketNumber,
    position: 0,
    attente: minutesLeft,
    cabinet: clinicName,
  });
}

export function buildSmsCalledMessage(clinicName: string, ticketNumber: number): string {
  return buildSmsMessage("called", {
    nom: "",
    ticket: ticketNumber,
    position: 0,
    attente: 0,
    cabinet: clinicName,
  });
}

export function buildSmsWithdrawnMessage(clinicName: string, ticketNumber: number): string {
  return buildSmsMessage("withdrawn", {
    nom: "",
    ticket: ticketNumber,
    position: 0,
    attente: 0,
    cabinet: clinicName,
  });
}