From 1259669c9db95c98282f6cecbb6487e0248c61e3 Mon Sep 17 00:00:00 2001
From: Dragory <2606411+Dragory@users.noreply.github.com>
Date: Sun, 9 Jun 2019 20:04:40 +0300
Subject: [PATCH] Add support for timed blocks. Add !is_blocked.

---
 README.md                                     |   7 +-
 ...9193213_add_expires_at_to_blocked_users.js |  11 ++
 src/data/blocked.js                           |  57 +++++++--
 src/modules/block.js                          | 111 ++++++++++++++----
 src/utils.js                                  |   2 +-
 5 files changed, 151 insertions(+), 37 deletions(-)
 create mode 100644 db/migrations/20190609193213_add_expires_at_to_blocked_users.js

diff --git a/README.md b/README.md
index 41b9f8f..4d44abe 100644
--- a/README.md
+++ b/README.md
@@ -35,10 +35,11 @@ See [CHANGELOG.md](CHANGELOG.md)
 `!logs <user>` Lists previous modmail logs with the specified user  
 `!block <user>` Blocks the specified user from using modmail  
 `!unblock <user>` Unblocks the specified user from using modmail  
+`!is_blocked <user>` Checks whether the user is blocked and for how long  
 `!s <shortcut> <text>` Adds a snippet (a canned response). See below for how to use it.  
 `!edit_snippet <shortcut> <text>` Edits an existing snippet (alias `!es`)  
 `!delete_snippet <shortcut>` Deletes the specified snippet (alias `!ds`)  
-`!snippets` Lists all available snippets
+`!snippets` Lists all available snippets  
 `!version` Print the version of the bot you're running  
 `!newthread <user>` Opens a new thread with the specified user
 
@@ -47,8 +48,8 @@ See [CHANGELOG.md](CHANGELOG.md)
 `!anonreply <text>` Sends an anonymous reply to the user in the format "Role: text" (alias `!ar`)  
 `!close <time>` Closes the modmail thread. If a time is specified, the thread is scheduled to be closed later. Scheduled closing is cancelled if a message is sent to or received from the user.  
 `!logs` Lists previous modmail logs with this user  
-`!block` Blocks the user from using modmail  
-`!unblock` Unblocks the user from using modmail  
+`!block <time>` Blocks the user from using modmail. If a time is specified, the block is temporary.  
+`!unblock <time>` Unblocks the user from using modmail. If a time is specified, the user will be scheduled to be unblocked after that time.  
 `!!shortcut` Reply with a snippet. Replace `shortcut` with the snippet's actual shortcut.  
 `!!!shortcut` Reply with a snippet anonymously. Replace `shortcut` with the snippet's actual shortcut.  
 `!move <category>` If `allowMove` is enabled, moves the thread channel to the specified category  
diff --git a/db/migrations/20190609193213_add_expires_at_to_blocked_users.js b/db/migrations/20190609193213_add_expires_at_to_blocked_users.js
new file mode 100644
index 0000000..ea456a6
--- /dev/null
+++ b/db/migrations/20190609193213_add_expires_at_to_blocked_users.js
@@ -0,0 +1,11 @@
+exports.up = async function(knex, Promise) {
+  await knex.schema.table('blocked_users', table => {
+    table.dateTime('expires_at').nullable();
+  });
+};
+
+exports.down = async function(knex, Promise) {
+  await knex.schema.table('blocked_users', table => {
+    table.dropColumn('expires_at');
+  });
+};
diff --git a/src/data/blocked.js b/src/data/blocked.js
index 50b494f..81c1214 100644
--- a/src/data/blocked.js
+++ b/src/data/blocked.js
@@ -1,17 +1,28 @@
 const moment = require('moment');
 const knex = require('../knex');
 
+/**
+ * @param {String} userId
+ * @returns {Promise<{ isBlocked: boolean, expiresAt: string }>}
+ */
+async function getBlockStatus(userId) {
+  const row = await knex('blocked_users')
+    .where('user_id', userId)
+    .first();
+
+  return {
+    isBlocked: !! row,
+    expiresAt: row && row.expires_at
+  };
+}
+
 /**
  * Checks whether userId is blocked
  * @param {String} userId
  * @returns {Promise<Boolean>}
  */
 async function isBlocked(userId) {
-  const row = await knex('blocked_users')
-    .where('user_id', userId)
-    .first();
-
-  return !! row;
+  return (await getBlockStatus(userId)).isBlocked;
 }
 
 /**
@@ -21,7 +32,7 @@ async function isBlocked(userId) {
  * @param {String} blockedBy
  * @returns {Promise}
  */
-async function block(userId, userName = '', blockedBy = null) {
+async function block(userId, userName = '', blockedBy = null, expiresAt = null) {
   if (await isBlocked(userId)) return;
 
   return knex('blocked_users')
@@ -29,7 +40,8 @@ async function block(userId, userName = '', blockedBy = null) {
       user_id: userId,
       user_name: userName,
       blocked_by: blockedBy,
-      blocked_at: moment.utc().format('YYYY-MM-DD HH:mm:ss')
+      blocked_at: moment.utc().format('YYYY-MM-DD HH:mm:ss'),
+      expires_at: expiresAt
     });
 }
 
@@ -44,8 +56,39 @@ async function unblock(userId) {
     .delete();
 }
 
+/**
+ * Updates the expiry time of the block for the given userId
+ * @param {String} userId
+ * @param {String} expiresAt
+ * @returns {Promise<void>}
+ */
+async function updateExpiryTime(userId, expiresAt) {
+  return knex('blocked_users')
+    .where('user_id', userId)
+    .update({
+      expires_at: expiresAt
+    });
+}
+
+/**
+ * @returns {String[]}
+ */
+async function getExpiredBlocks() {
+  const now = moment.utc().format('YYYY-MM-DD HH:mm:ss');
+
+  const blocks = await knex('blocked_users')
+    .whereNotNull('expires_at')
+    .where('expires_at', '<=', now)
+    .select();
+
+  return blocks.map(block => block.user_id);
+}
+
 module.exports = {
+  getBlockStatus,
   isBlocked,
   block,
   unblock,
+  updateExpiryTime,
+  getExpiredBlocks,
 };
diff --git a/src/modules/block.js b/src/modules/block.js
index e913968..a6d5d1b 100644
--- a/src/modules/block.js
+++ b/src/modules/block.js
@@ -1,3 +1,5 @@
+const humanizeDuration = require('humanize-duration');
+const moment = require('moment');
 const threadUtils = require('../threadUtils');
 const blocked = require("../data/blocked");
 const utils = require("../utils");
@@ -5,38 +7,95 @@ const utils = require("../utils");
 module.exports = bot => {
   const addInboxServerCommand = (...args) => threadUtils.addInboxServerCommand(bot, ...args);
 
-  addInboxServerCommand('block', (msg, args, thread) => {
-    async function block(userId) {
-      const user = bot.users.get(userId);
-      await blocked.block(userId, (user ? `${user.username}#${user.discriminator}` : ''), msg.author.id);
-      msg.channel.createMessage(`Blocked <@${userId}> (id ${userId}) from modmail`);
+  async function removeExpiredBlocks() {
+    const expiredBlocks = await blocked.getExpiredBlocks();
+    const logChannel = utils.getLogChannel();
+    for (const userId of expiredBlocks) {
+      await blocked.unblock(userId);
+      logChannel.createMessage(`Block of <@!${userId}> (id \`${userId}\`) expired`);
+    }
+  }
+
+  async function expiredBlockLoop() {
+    try {
+      removeExpiredBlocks();
+    } catch (e) {
+      console.error(e);
     }
 
-    if (args.length > 0) {
-      // User mention/id as argument
-      const userId = utils.getUserMention(args.join(' '));
-      if (! userId) return;
-      block(userId);
-    } else if (thread) {
-      // Calling !block without args in a modmail thread blocks the user of that thread
-      block(thread.user_id);
+    setTimeout(expiredBlockLoop, 2000);
+  }
+
+  bot.on('ready', expiredBlockLoop);
+
+  addInboxServerCommand('block', async (msg, args, thread) => {
+    const userIdToBlock = args[0]
+      ? utils.getUserMention(args[0])
+      : thread && thread.user_id;
+
+    if (! userIdToBlock) return;
+
+    const isBlocked = await blocked.isBlocked(userIdToBlock);
+    if (isBlocked) {
+      msg.channel.createMessage('User is already blocked');
+      return;
+    }
+
+    const expiryTime = args[1] ? utils.convertDelayStringToMS(args[1]) : null;
+    const expiresAt = expiryTime
+      ? moment.utc().add(expiryTime, 'ms').format('YYYY-MM-DD HH:mm:ss')
+      : null;
+
+    const user = bot.users.get(userIdToBlock);
+    await blocked.block(userIdToBlock, (user ? `${user.username}#${user.discriminator}` : ''), msg.author.id, expiresAt);
+
+    if (expiresAt) {
+      const humanized = humanizeDuration(expiryTime, { largest: 2, round: true });
+      msg.channel.createMessage(`Blocked <@${userIdToBlock}> (id \`${userIdToBlock}\`) from modmail for ${humanized}`);
+    } else {
+      msg.channel.createMessage(`Blocked <@${userIdToBlock}> (id \`${userIdToBlock}\`) from modmail indefinitely`);
     }
   });
 
-  addInboxServerCommand('unblock', (msg, args, thread) => {
-    async function unblock(userId) {
-      await blocked.unblock(userId);
-      msg.channel.createMessage(`Unblocked <@${userId}> (id ${userId}) from modmail`);
-    }
+  addInboxServerCommand('unblock', async (msg, args, thread) => {
+    const userIdToUnblock = args[0]
+      ? utils.getUserMention(args[0])
+      : thread && thread.user_id;
 
-    if (args.length > 0) {
-      // User mention/id as argument
-      const userId = utils.getUserMention(args.join(' '));
-      if (! userId) return;
-      unblock(userId);
-    } else if (thread) {
-      // Calling !unblock without args in a modmail thread unblocks the user of that thread
-      unblock(thread.user_id);
+    if (! userIdToUnblock) return;
+
+    const unblockDelay = args[1] ? utils.convertDelayStringToMS(args[1]) : null;
+    const unblockAt = unblockDelay
+      ? moment.utc().add(unblockDelay, 'ms').format('YYYY-MM-DD HH:mm:ss')
+      : null;
+
+    const user = bot.users.get(userIdToUnblock);
+    if (unblockAt) {
+      const humanized = humanizeDuration(unblockDelay, { largest: 2, round: true });
+      await blocked.updateExpiryTime(userIdToUnblock, unblockAt);
+      msg.channel.createMessage(`Scheduled <@${userIdToUnblock}> (id \`${userIdToUnblock}\`) to be unblocked in ${humanized}`);
+    } else {
+      await blocked.unblock(userIdToUnblock);
+      msg.channel.createMessage(`Unblocked <@${userIdToUnblock}> (id ${userIdToUnblock}) from modmail`);
+    }
+  });
+
+  addInboxServerCommand('is_blocked', async (msg, args, thread) => {
+    const userIdToCheck = args[0]
+      ? utils.getUserMention(args[0])
+      : thread && thread.user_id;
+
+    if (! userIdToCheck) return;
+
+    const blockStatus = await blocked.getBlockStatus(userIdToCheck);
+    if (blockStatus.isBlocked) {
+      if (blockStatus.expiresAt) {
+        msg.channel.createMessage(`<@!${userIdToCheck}> (id \`${userIdToCheck}\`) is blocked until ${blockStatus.expiresAt} (UTC)`);
+      } else {
+        msg.channel.createMessage(`<@!${userIdToCheck}> (id \`${userIdToCheck}\`) is blocked indefinitely`);
+      }
+    } else {
+      msg.channel.createMessage(`<@!${userIdToCheck}> (id \`${userIdToCheck}\`) is NOT blocked`);
     }
   });
 };
diff --git a/src/utils.js b/src/utils.js
index 52c21c0..7e04891 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -224,7 +224,7 @@ const delayStringRegex = /^([0-9]+)(?:([dhms])[a-z]*)?/i;
 /**
  * Turns a "delay string" such as "1h30m" to milliseconds
  * @param {String} str
- * @returns {Number}
+ * @returns {Number|null}
  */
 function convertDelayStringToMS(str) {
   let match;