const crypto = require("crypto");

const { Bot, Keyboard } = require("grammy");

const log = require("./log");
const util = require("./util");
const cache = require("./cache");
const config = require("./config");
const request = require("./request");

const bot = new Bot(config.get("TELEGRAM_TOKEN"));
log.debug("bot initialized");

bot.command("start", async (ctx) => {
  log.debug(ctx.update, "/start cmd executed");
  const tgLinked = await cache.get(ctx.msg.from.id);
  log.debug({ cache: tgLinked }, "cache request:tgLinked");

  if (tgLinked) {
    const localSessionId = crypto.randomBytes(16).toString("hex");
    await cache.set(tgLinked, localSessionId);

    const res = util.parseUssdResponse(
      await request.proxy(localSessionId, tgLinked)
    );

    return ctx.reply(res.text, {
      reply_markup: {
        resize_keyboard: true,
        keyboard: res.keyboard,
      },
    });
  }

  const keyboard = new Keyboard();
  return await ctx.reply(
    "Click on the button  below to link your phone number.",
    {
      reply_markup: keyboard.requestContact("Link Phone"),
    }
  );
});

bot.on("message:text", async (ctx) => {
  log.debug(ctx.update, "msg:text received");
  const tgLinked = await cache.get(ctx.msg.from.id);
  const localSessionId = await cache.get(tgLinked);
  log.debug({ cache: localSessionId }, "cache request:localSessionId");

  if (tgLinked && localSessionId) {
    const res = util.parseUssdResponse(
      await request.proxy(localSessionId, tgLinked, ctx.msg.text)
    );

    if (res.code === "END") {
      await cache.del(tgLinked);

      return await ctx.reply(res.text, {
        reply_markup: { remove_keyboard: true },
      });
    }

    return await ctx.reply(res.text, {
      reply_markup: {
        resize_keyboard: true,
        keyboard: res.keyboard,
      },
    });
  }

  return await ctx.reply(
    "Session expired or account not linked. /start the bot again to access your Sarafu account."
  );
});

bot.on("msg:contact", async (ctx) => {
  log.debug(ctx.update, "msg:contact received");
  const contact = ctx.msg.contact;

  if (ctx.msg.reply_to_message.from.is_bot && ctx.from.id === contact.user_id) {
    if (contact.phone_number.slice(0, 4) !== "+254") {
      return ctx.reply("Sarafu is only available in Kenya at the moment.");
    }

    await cache.set(contact.user_id, contact.phone_number.slice(1));

    return ctx.reply(
      "Phone number successfully linked. /start the bot again to access your Sarafu account."
    );
  }

  log.info(ctx.update.user, "contact spoof attempted");
  return ctx.reply("Could not verify sent contact.");
});

module.exports = bot;