From 8439512f1aaf619e5e007e11c02128e53b909c16 Mon Sep 17 00:00:00 2001
From: Cadence Ember <cadence@disroot.org>
Date: Thu, 23 Nov 2023 15:51:25 +1300
Subject: [PATCH] Add snowflake timestamp converter functions

---
 .../message-to-event.embeds.test.js           | 26 -------------------
 discord/utils.js                              | 14 ++++++++++
 discord/utils.test.js                         | 23 ++++++++++++++++
 m2d/converters/event-to-message.test.js       |  3 ++-
 4 files changed, 39 insertions(+), 27 deletions(-)
 create mode 100644 discord/utils.test.js

diff --git a/d2m/converters/message-to-event.embeds.test.js b/d2m/converters/message-to-event.embeds.test.js
index 173e016..b339687 100644
--- a/d2m/converters/message-to-event.embeds.test.js
+++ b/d2m/converters/message-to-event.embeds.test.js
@@ -3,32 +3,6 @@ const {messageToEvent} = require("./message-to-event")
 const data = require("../../test/data")
 const Ty = require("../../types")
 
-/**
- * @param {string} roomID
- * @param {string} eventID
- * @returns {(roomID: string, eventID: string) => Promise<Ty.Event.Outer<Ty.Event.M_Room_Message>>}
- */
-function mockGetEvent(t, roomID_in, eventID_in, outer) {
-	return async function(roomID, eventID) {
-		t.equal(roomID, roomID_in)
-		t.equal(eventID, eventID_in)
-		return new Promise(resolve => {
-			setTimeout(() => {
-				resolve({
-					event_id: eventID_in,
-					room_id: roomID_in,
-					origin_server_ts: 1680000000000,
-					unsigned: {
-						age: 2245,
-						transaction_id: "$local.whatever"
-					},
-					...outer
-				})
-			})
-		})
-	}
-}
-
 test("message2event embeds: nothing but a field", async t => {
 	const events = await messageToEvent(data.message_with_embeds.nothing_but_a_field, data.guild.general, {})
 	t.deepEqual(events, [{
diff --git a/discord/utils.js b/discord/utils.js
index 8856aa7..ceb4468 100644
--- a/discord/utils.js
+++ b/discord/utils.js
@@ -2,6 +2,8 @@
 
 const DiscordTypes = require("discord-api-types/v10")
 
+const EPOCH = 1420070400000
+
 /**
  * @param {string[]} userRoles
  * @param {DiscordTypes.APIGuild["roles"]} guildRoles
@@ -56,5 +58,17 @@ function isWebhookMessage(message) {
 	return message.webhook_id && !isInteractionResponse
 }
 
+/** @param {string} snowflake */
+function snowflakeToTimestampExact(snowflake) {
+	return Number(BigInt(snowflake) >> 22n) + EPOCH
+}
+
+/** @param {number} timestamp */
+function timestampToSnowflakeInexact(timestamp) {
+	return String((timestamp - EPOCH) * 2**22)
+}
+
 module.exports.getPermissions = getPermissions
 module.exports.isWebhookMessage = isWebhookMessage
+module.exports.snowflakeToTimestampExact = snowflakeToTimestampExact
+module.exports.timestampToSnowflakeInexact = timestampToSnowflakeInexact
diff --git a/discord/utils.test.js b/discord/utils.test.js
new file mode 100644
index 0000000..fd064ef
--- /dev/null
+++ b/discord/utils.test.js
@@ -0,0 +1,23 @@
+const {test} = require("supertape")
+const data = require("../test/data")
+const utils = require("./utils")
+
+test("is webhook message: identifies bot interaction response as not a message", t => {
+	t.equal(utils.isWebhookMessage(data.interaction_message.thinking_interaction), false)
+})
+
+test("is webhook message: identifies webhook interaction response as not a message", t => {
+	t.equal(utils.isWebhookMessage(data.interaction_message.thinking_interaction_without_bot_user), false)
+})
+
+test("is webhook message: identifies webhook message as a message", t => {
+	t.equal(utils.isWebhookMessage(data.special_message.bridge_echo_webhook), true)
+})
+
+test("discord utils: converts snowflake to timestamp", t => {
+	t.equal(utils.snowflakeToTimestampExact("86913608335773696"), 1440792219004)
+})
+
+test("discerd utils: converts timestamp to snowflake", t => {
+	t.match(utils.timestampToSnowflakeInexact(1440792219004), /^869136083357.....$/)
+})
diff --git a/m2d/converters/event-to-message.test.js b/m2d/converters/event-to-message.test.js
index 8bd4223..1af5e42 100644
--- a/m2d/converters/event-to-message.test.js
+++ b/m2d/converters/event-to-message.test.js
@@ -2168,7 +2168,8 @@ test("event2message: guessed @mentions may join members to mention", async t =>
 	const subtext = {
 		user: {
 			id: "321876634777218072",
-			username: "subtext",
+			username: "subtextual",
+			global_name: "subtext",
 			discriminator: "0"
 		}
 	}