diff --git a/lib/discourse_chat/provider/slack/slack_command_controller.rb b/lib/discourse_chat/provider/slack/slack_command_controller.rb
index 8d636db..6c1a011 100644
--- a/lib/discourse_chat/provider/slack/slack_command_controller.rb
+++ b/lib/discourse_chat/provider/slack/slack_command_controller.rb
@@ -52,9 +52,9 @@ module DiscourseChat::Provider::SlackProvider
         return { text: I18n.t("chat_integration.provider.slack.transcript.api_required") }
       end
 
-      requested_messages = 10
-
+      requested_messages = nil
       first_message_ts = nil
+
       slack_url_regex = /^https:\/\/\S+\.slack\.com\/archives\/\S+\/p([0-9]{16})\/?$/
       if tokens.size > 1 && match = slack_url_regex.match(tokens[1])
         first_message_ts = match.captures[0].insert(10, '.')
@@ -66,12 +66,19 @@ module DiscourseChat::Provider::SlackProvider
         end
       end
 
-      transcript = SlackTranscript.load_transcript(slack_channel_id: slack_channel_id,
-                                                   channel_name: channel_name,
-                                                   requested_messages: requested_messages,
-                                                   first_message_ts: first_message_ts)
+      error_message = { text: I18n.t("chat_integration.provider.slack.transcript.error") }
 
-      return { text: I18n.t("chat_integration.provider.slack.transcript.error") } unless transcript
+      return error_message unless transcript = SlackTranscript.new(channel_name: channel_name, channel_id: slack_channel_id)
+      return error_message unless transcript.load_user_data
+      return error_message unless transcript.load_chat_history
+
+      if first_message_ts
+        return error_message unless transcript.set_first_message_by_ts(first_message_ts)
+      elsif requested_messages
+        transcript.set_first_message_by_index(-requested_messages)
+      else
+        transcript.set_first_message_by_index(-10) unless transcript.guess_first_message
+      end
 
       return transcript.build_slack_ui
 
@@ -92,16 +99,16 @@ module DiscourseChat::Provider::SlackProvider
       first_message = (action_name == 'first_message') ? changed_val : constant_val
       last_message = (action_name == 'first_message') ? constant_val : changed_val
 
-      transcript = SlackTranscript.load_transcript(slack_channel_id: json[:channel][:id],
-                                                   channel_name: "##{json[:channel][:name]}",
-                                                   first_message_ts: first_message,
-                                                   last_message_ts: last_message)
+      error_message = { text: I18n.t("chat_integration.provider.slack.transcript.error") }
 
-      return { text: I18n.t("chat_integration.provider.slack.transcript.error") } unless transcript
+      return error_message unless transcript = SlackTranscript.new(channel_name: "##{json[:channel][:name]}", channel_id: json[:channel][:id])
+      return error_message unless transcript.load_user_data
+      return error_message unless transcript.load_chat_history
 
-      message = transcript.build_slack_ui
+      return error_message unless transcript.set_first_message_by_ts(first_message)
+      return error_message unless transcript.set_last_message_by_ts(last_message)
 
-      return message
+      return transcript.build_slack_ui
     end
 
     def slack_token_valid?
diff --git a/lib/discourse_chat/provider/slack/slack_provider.rb b/lib/discourse_chat/provider/slack/slack_provider.rb
index 1e1496c..9e08c75 100644
--- a/lib/discourse_chat/provider/slack/slack_provider.rb
+++ b/lib/discourse_chat/provider/slack/slack_provider.rb
@@ -151,5 +151,5 @@ module DiscourseChat::Provider::SlackProvider
 end
 
 require_relative "slack_message_formatter.rb"
-require_relative "slack_transcript_helper.rb"
+require_relative "slack_transcript.rb"
 require_relative "slack_command_controller.rb"
diff --git a/lib/discourse_chat/provider/slack/slack_transcript_helper.rb b/lib/discourse_chat/provider/slack/slack_transcript.rb
similarity index 61%
rename from lib/discourse_chat/provider/slack/slack_transcript_helper.rb
rename to lib/discourse_chat/provider/slack/slack_transcript.rb
index 77074b8..82025fc 100644
--- a/lib/discourse_chat/provider/slack/slack_transcript_helper.rb
+++ b/lib/discourse_chat/provider/slack/slack_transcript.rb
@@ -10,6 +10,8 @@ module DiscourseChat::Provider::SlackProvider
         return user['name']
       elsif @raw.key?("username")
         return @raw["username"]
+      else
+        return nil
       end
     end
 
@@ -82,39 +84,83 @@ module DiscourseChat::Provider::SlackProvider
   end
 
   class SlackTranscript
-    attr_reader :users, :channel_id
+    attr_reader :users, :channel_id, :messages
 
-    def initialize(raw_history:, raw_users:, channel_id:, channel_name:, requested_messages: nil, first_message_ts: nil, last_message_ts: nil)
+    def initialize(channel_name:, channel_id:)
+      @channel_name = channel_name
+      @channel_id = channel_id
 
-      requested_messages ||= 10
+      @first_message_index = 0
+      @last_message_index = -1 # We can use negative array indicies to select the last message - fancy!
+    end
 
-      raw_messages = raw_history['messages'].reverse
-      # Build some message objects
-      @messages = []
-      raw_messages.each_with_index do |message, index|
-        next unless message["type"] == "message"
-        this_message = SlackMessage.new(message, self)
-        @messages << this_message
+    def set_first_message_by_ts(ts)
+      message_index = @messages.find_index { |m| m.ts == ts }
+      @first_message_index = message_index if message_index
+    end
 
-        # Auto set first and last based on requested_messages
-        @first_message = this_message if index == raw_messages.length - requested_messages
-        @last_message = this_message if index == raw_messages.length - 1
+    def set_last_message_by_ts(ts)
+      message_index = @messages.find_index { |m| m.ts == ts }
+      @last_message_index = message_index if message_index
+    end
+
+    def set_first_message_by_index(val)
+      @first_message_index = val if @messages[val]
+    end
+
+    def set_last_message_by_index(val)
+      @last_message_index = val if @messages[val]
+    end
+
+    # Apply a heuristic to decide which is the first message in the current conversation
+    def guess_first_message(skip_messages: 5) # Can skip the last n messages
+
+      possible_first_messages = @messages[0..-skip_messages]
+
+      # Work through the messages in order. If a gap is found, this could be the first message
+      new_first_message_index = nil
+      previous_message_ts = @messages[-skip_messages].ts.split('.').first.to_i
+      possible_first_messages.each_with_index do |message, index|
+
+        # Calculate the time since the last message
+        this_ts = message.ts.split('.').first.to_i
+        time_since_previous_message = this_ts - previous_message_ts
+
+        # If greater than 3 minutes, this could be the first message
+        if time_since_previous_message > 3.minutes
+          new_first_message_index = index
+        end
+
+        previous_message_ts = this_ts
       end
 
-      @first_message = @messages.find { |m| m.ts == first_message_ts } || @first_message if first_message_ts
-      @last_message = @messages.find { |m| m.ts == last_message_ts } || @last_message if last_message_ts
+      if new_first_message_index
+        @first_message_index = new_first_message_index
+        return true
+      else
+        return false
+      end
+    end
 
-      @first_message_index = @messages.index(@first_message)
-      @last_message_index = @messages.index(@last_message)
+    def first_message
+      return @messages[@first_message_index]
+    end
 
-      @users = raw_users['members']
-      @channel_id = channel_id
-      @channel_name = channel_name
+    def last_message
+      return @messages[@last_message_index]
+    end
+
+    # These two methods convert potentially negative array indices into positive ones
+    def first_message_number
+      return @first_message_index < 0 ? @messages.length + @first_message_index : @first_message_index
+    end
+    def last_message_number
+      return @last_message_index < 0 ? @messages.length + @last_message_index : @last_message_index
     end
 
     def build_transcript
       post_content = "[quote]\n"
-      post_content << "[**#{I18n.t('chat_integration.provider.slack.transcript.view_on_slack', name: @channel_name)}**](#{@first_message.url})\n"
+      post_content << "[**#{I18n.t('chat_integration.provider.slack.transcript.view_on_slack', name: @channel_name)}**](#{first_message.url})\n"
 
       all_avatars = {}
 
@@ -162,41 +208,41 @@ module DiscourseChat::Provider::SlackProvider
       return { text: "<#{link}|#{I18n.t("chat_integration.provider.slack.transcript.post_to_discourse")}>",
                attachments: [
                 {
-                  pretext: I18n.t("chat_integration.provider.slack.transcript.first_message_pretext", n: @messages.length - @first_message_index),
-                  fallback: "#{@first_message.username} - #{@first_message.raw_text}",
+                  pretext: I18n.t("chat_integration.provider.slack.transcript.first_message_pretext", n: @messages.length - first_message_number),
+                  fallback: "#{first_message.username} - #{first_message.raw_text}",
                   color: "#007AB8",
-                  author_name: @first_message.username,
-                  author_icon: @first_message.avatar,
-                  text: @first_message.raw_text,
+                  author_name: first_message.username,
+                  author_icon: first_message.avatar,
+                  text: first_message.raw_text,
                   footer: I18n.t("chat_integration.provider.slack.transcript.posted_in", name: @channel_name),
-                  ts: @first_message.ts,
-                  callback_id: @last_message.ts,
+                  ts: first_message.ts,
+                  callback_id: last_message.ts,
                   actions: [
                     {
                         name: "first_message",
                         text: I18n.t("chat_integration.provider.slack.transcript.change_first_message"),
                         type: "select",
-                        options: first_message_options = @messages[ [(@first_message_index - 20), 0].max .. @last_message_index]
+                        options: first_message_options = @messages[ [(first_message_number - 20), 0].max .. last_message_number]
                             .map { |m| { text: "#{m.username}: #{m.text}", value: m.ts } }
                     }
                   ],
                 },
                 {
-                  pretext: I18n.t("chat_integration.provider.slack.transcript.last_message_pretext", n: @messages.length - @last_message_index),
-                  fallback: "#{@last_message.username} - #{@last_message.raw_text}",
+                  pretext: I18n.t("chat_integration.provider.slack.transcript.last_message_pretext", n: @messages.length - last_message_number),
+                  fallback: "#{last_message.username} - #{last_message.raw_text}",
                   color: "#007AB8",
-                  author_name: @last_message.username,
-                  author_icon: @last_message.avatar,
-                  text: @last_message.raw_text,
+                  author_name: last_message.username,
+                  author_icon: last_message.avatar,
+                  text: last_message.raw_text,
                   footer: I18n.t("chat_integration.provider.slack.transcript.posted_in", name: @channel_name),
-                  ts: @last_message.ts,
-                  callback_id: @first_message.ts,
+                  ts: last_message.ts,
+                  callback_id: first_message.ts,
                   actions: [
                     {
                         name: "last_message",
                         text: I18n.t("chat_integration.provider.slack.transcript.change_last_message"),
                         type: "select",
-                        options: @messages[@first_message_index..(@last_message_index + 20)]
+                        options: @messages[first_message_number..(last_message_number + 20)]
                             .map { |m| { text: "#{m.username}: #{m.text}", value: m.ts } }
                     }
                   ],
@@ -206,7 +252,7 @@ module DiscourseChat::Provider::SlackProvider
              }
     end
 
-    def self.load_user_data
+    def load_user_data
       http = Net::HTTP.new("slack.com", 443)
       http.use_ssl = true
 
@@ -216,10 +262,12 @@ module DiscourseChat::Provider::SlackProvider
       return false unless response.kind_of? Net::HTTPSuccess
       json = JSON.parse(response.body)
       return false unless json['ok']
-      return json
+
+      @users = json['members']
+
     end
 
-    def self.load_chat_history(slack_channel_id:, count: 500)
+    def load_chat_history(count: 500)
       http = Net::HTTP.new("slack.com", 443)
       http.use_ssl = true
 
@@ -227,7 +275,7 @@ module DiscourseChat::Provider::SlackProvider
 
       data = {
         token: SiteSetting.chat_integration_slack_access_token,
-        channel: slack_channel_id,
+        channel: @channel_id,
         count: count
       }
 
@@ -236,21 +284,17 @@ module DiscourseChat::Provider::SlackProvider
       return false unless response.kind_of? Net::HTTPSuccess
       json = JSON.parse(response.body)
       return false unless json['ok']
-      return json
-    end
 
-    def self.load_transcript(slack_channel_id:, channel_name:, requested_messages: nil, first_message_ts: nil, last_message_ts: nil)
-      return false unless raw_users = self.load_user_data
+      raw_messages = json['messages'].reverse
 
-      return false unless raw_history = self.load_chat_history(slack_channel_id: slack_channel_id)
+      # Build some message objects
+      @messages = []
+      raw_messages.each_with_index do |message, index|
+        next unless message["type"] == "message"
+        this_message = SlackMessage.new(message, self)
+        @messages << this_message
+      end
 
-      self.new(raw_history: raw_history,
-               raw_users: raw_users,
-               channel_id: slack_channel_id,
-               channel_name: channel_name,
-               requested_messages: requested_messages,
-               first_message_ts: first_message_ts,
-               last_message_ts: last_message_ts)
     end
   end
 
diff --git a/spec/lib/discourse_chat/provider/slack/slack_command_controller_spec.rb b/spec/lib/discourse_chat/provider/slack/slack_command_controller_spec.rb
index f2690bf..a11b502 100644
--- a/spec/lib/discourse_chat/provider/slack/slack_command_controller_spec.rb
+++ b/spec/lib/discourse_chat/provider/slack/slack_command_controller_spec.rb
@@ -111,23 +111,120 @@ describe 'Slack Command Controller', type: :request do
       end
 
       describe 'post transcript' do
+        let(:messages_fixture) {
+          [
+            {
+              "type": "message",
+              "user": "U6JSSESES",
+              "text": "Yeah, should make posting slack transcripts much easier",
+              "ts": "1501801665.062694"
+            },
+            {
+                "type": "message",
+                "user": "U5Z773QLS",
+                "text": "Oooh a new discourse plugin???",
+                "ts": "1501801643.056375"
+            },
+            {
+                "type": "message",
+                "user": "U6E2W7R8C",
+                "text": "Which one?",
+                "ts": "1501801634.053761"
+            },
+            {
+                "type": "message",
+                "user": "U6JSSESES",
+                "text": "So, who's interested in the new <https://meta.discourse.org|discourse plugin>?",
+                "ts": "1501801629.052212"
+            },
+            {
+                  "text": "",
+                  "username": "Test Community",
+                  "bot_id": "B6C6JNUDN",
+                  "attachments": [
+                      {
+                          "author_name": "@david",
+                          "fallback": "Discourse can now be integrated with Mattermost! - @david",
+                          "text": "Hey <http://localhost/groups/team|@team>, what do you think about this?",
+                          "title": "Discourse can now be integrated with Mattermost! [Announcements] ",
+                          "id": 1,
+                          "title_link": "http://localhost:3000/t/discourse-can-now-be-integrated-with-mattermost/51/4",
+                          "color": "283890",
+                          "mrkdwn_in": [
+                              "text"
+                          ]
+                      }
+                  ],
+                  "type": "message",
+                  "subtype": "bot_message",
+                  "ts": "1501615820.949638"
+              },
+              {
+                  "type": "message",
+                  "user": "U5Z773QLS",
+                  "text": "Let’s try some *bold text*",
+                  "ts": "1501093331.439776"
+              },
+
+          ]
+        }
+
         before do
           SiteSetting.chat_integration_slack_access_token = 'abcde'
         end
 
-        it 'generates a transcript properly' do
-          stub1 = stub_request(:post, "https://slack.com/api/users.list").to_return(body: '{"ok":true,"members":[{"id":"U5Z773QLS","name":"david","profile":{"icon_24":"https://example.com/avatar"}}]}')
-          stub2 = stub_request(:post, "https://slack.com/api/channels.history").to_return(body: '{"ok":true,"messages":[{"type":"message","user":"U5Z773QLS","text":"And this is a slack message with an attachment: <https:\/\/meta.discourse.org>","attachments":[{"title":"Discourse Meta","title_link":"https:\/\/meta.discourse.org","text":"Discussion about the next-generation open source Discourse forum software","fallback":"Discourse Meta","thumb_url":"https:\/\/discourse-meta.s3-us-west-1.amazonaws.com\/original\/3X\/c\/b\/cb4bec8901221d4a646e45e1fa03db3a65e17f59.png","from_url":"https:\/\/meta.discourse.org","thumb_width":350,"thumb_height":349,"service_icon":"https:\/\/discourse-meta.s3-us-west-1.amazonaws.com\/original\/3X\/c\/b\/cb4bec8901221d4a646e45e1fa03db3a65e17f59.png","service_name":"meta.discourse.org","id":1}],"ts":"1500910064.045243"},{"type":"message","user":"U5Z773QLS","text":"Hello world, this is a slack message","ts":"1500910051.036792"}],"has_more":true}')
+        context "with valid slack responses" do
+          before do
+            stub1 = stub_request(:post, "https://slack.com/api/users.list").to_return(body: '{"ok":true,"members":[{"id":"U5Z773QLS","name":"david","profile":{"icon_24":"https://example.com/avatar"}}]}')
+            stub2 = stub_request(:post, "https://slack.com/api/channels.history").to_return(body: { ok: true, messages: messages_fixture }.to_json)
+          end
 
-          post "/chat-integration/slack/command.json",
-            text: "post 2",
-            channel_name: 'general',
-            channel_id: 'C6029G78F',
-            token: token
+          it 'generates the transcript UI properly' do
+            post "/chat-integration/slack/command.json",
+              text: "post",
+              channel_name: 'general',
+              channel_id: 'C6029G78F',
+              token: token
 
-          json = JSON.parse(response.body)
+            json = JSON.parse(response.body)
+            expect(json["attachments"].length).to eq(2)
+          end
 
-          # expect(json["text"]).to include(I18n.t("chat_integration.provider.slack.post_to_discourse"))
+          it 'can select by url' do
+            post "/chat-integration/slack/command.json",
+              text: "post https://sometestslack.slack.com/archives/C6029G78F/p1501801629052212",
+              channel_name: 'general',
+              channel_id: 'C6029G78F',
+              token: token
+
+            json = JSON.parse(response.body)
+            expect(json["attachments"].length).to eq(2)
+            expect(json["attachments"][0]["ts"]).to eq("1501801629.052212")
+          end
+
+          it 'can select by count' do
+            post "/chat-integration/slack/command.json",
+              text: "post 4",
+              channel_name: 'general',
+              channel_id: 'C6029G78F',
+              token: token
+
+            json = JSON.parse(response.body)
+            expect(json["attachments"].length).to eq(2)
+            expect(json["attachments"][0]["ts"]).to eq("1501801629.052212")
+          end
+
+          it 'can auto select' do
+            post "/chat-integration/slack/command.json",
+              text: "post",
+              channel_name: 'general',
+              channel_id: 'C6029G78F',
+              token: token
+
+            json = JSON.parse(response.body)
+            expect(json["attachments"].length).to eq(2)
+            expect(json["attachments"][0]["ts"]).to eq("1501615820.949638")
+          end
         end
 
         it 'deals with failed API calls correctly' do
diff --git a/spec/lib/discourse_chat/provider/slack/slack_transcript_spec.rb b/spec/lib/discourse_chat/provider/slack/slack_transcript_spec.rb
new file mode 100644
index 0000000..3492210
--- /dev/null
+++ b/spec/lib/discourse_chat/provider/slack/slack_transcript_spec.rb
@@ -0,0 +1,237 @@
+require 'rails_helper'
+
+RSpec.describe DiscourseChat::Provider::SlackProvider::SlackTranscript do
+
+  let(:messages_fixture) {
+    [
+      {
+        "type": "message",
+        "user": "U6JSSESES",
+        "text": "Yeah, should make posting slack transcripts much easier",
+        "ts": "1501801665.062694"
+      },
+      {
+          "type": "message",
+          "user": "U5Z773QLS",
+          "text": "Oooh a new discourse plugin???",
+          "ts": "1501801643.056375"
+      },
+      {
+          "type": "message",
+          "user": "U6E2W7R8C",
+          "text": "Which one?",
+          "ts": "1501801634.053761"
+      },
+      {
+          "type": "message",
+          "user": "U6JSSESES",
+          "text": "So, who's interested in the new <https://meta.discourse.org|discourse plugin>?",
+          "ts": "1501801629.052212"
+      },
+      {
+            "text": "",
+            "username": "Test Community",
+            "bot_id": "B6C6JNUDN",
+            "attachments": [
+                {
+                    "author_name": "@david",
+                    "fallback": "Discourse can now be integrated with Mattermost! - @david",
+                    "text": "Hey <http://localhost/groups/team|@team>, what do you think about this?",
+                    "title": "Discourse can now be integrated with Mattermost! [Announcements] ",
+                    "id": 1,
+                    "title_link": "http://localhost:3000/t/discourse-can-now-be-integrated-with-mattermost/51/4",
+                    "color": "283890",
+                    "mrkdwn_in": [
+                        "text"
+                    ]
+                }
+            ],
+            "type": "message",
+            "subtype": "bot_message",
+            "ts": "1501615820.949638"
+        },
+        {
+            "type": "message",
+            "user": "U5Z773QLS",
+            "text": "Let’s try some *bold text*",
+            "ts": "1501093331.439776"
+        },
+
+    ]
+  }
+
+  let(:transcript) { described_class.new(channel_name: "#general", channel_id: "G1234") }
+  before do
+    SiteSetting.chat_integration_slack_access_token = "abcde"
+  end
+
+  describe 'loading users' do
+    it 'loads users correctly' do
+      stub_request(:post, "https://slack.com/api/users.list")
+        .with(body: { token: "abcde" })
+        .to_return(status: 200, body: { ok: true, members: [{ id: "U5Z773QLS", name: "awesomeguy", profile: { image_24: "https://example.com/avatar" } }] }.to_json)
+
+      expect(transcript.load_user_data).to be_truthy
+    end
+
+    it 'handles failed connection' do
+      stub_request(:post, "https://slack.com/api/users.list")
+        .to_return(status: 500, body: '')
+
+      expect(transcript.load_user_data).to be_falsey
+    end
+
+    it 'handles slack failure' do
+      stub_request(:post, "https://slack.com/api/users.list")
+        .to_return(status: 200, body: { ok: false }.to_json)
+
+      expect(transcript.load_user_data).to be_falsey
+    end
+  end
+
+  context 'with loaded users' do
+    before do
+      stub_request(:post, "https://slack.com/api/users.list")
+        .to_return(status: 200, body: { ok: true, members: [{ id: "U5Z773QLS", name: "awesomeguy", profile: { image_24: "https://example.com/avatar" } }] }.to_json)
+      transcript.load_user_data
+    end
+
+    describe 'loading history' do
+      it 'loads messages correctly' do
+        stub_request(:post, "https://slack.com/api/channels.history")
+          .with(body: hash_including(token: "abcde", channel: 'G1234'))
+          .to_return(status: 200, body: { ok: true, messages: messages_fixture }.to_json)
+
+          expect(transcript.load_chat_history).to be_truthy
+      end
+
+      it 'handles failed connection' do
+        stub_request(:post, "https://slack.com/api/channels.history")
+          .to_return(status: 500, body: {}.to_json)
+
+          expect(transcript.load_chat_history).to be_falsey
+      end
+
+      it 'handles slack failure' do
+        stub_request(:post, "https://slack.com/api/channels.history")
+          .to_return(status: 200, body: { ok: false }.to_json)
+
+          expect(transcript.load_chat_history).to be_falsey
+      end
+    end
+
+    context 'with loaded messages' do
+      before do
+        stub_request(:post, "https://slack.com/api/channels.history")
+          .with(body: hash_including(token: "abcde", channel: 'G1234'))
+          .to_return(status: 200, body: { ok: true, messages: messages_fixture }.to_json)
+        transcript.load_chat_history
+      end
+
+      it 'loads in chronological order' do # API presents in reverse chronological
+        expect(transcript.messages.first.ts).to eq('1501093331.439776')
+      end
+
+      it 'handles bold text' do
+        expect(transcript.messages.first.text).to eq("Let’s try some **bold text**")
+      end
+
+      it 'handles links' do
+        expect(transcript.messages[2].text).to eq("So, who's interested in the new [discourse plugin](https://meta.discourse.org)?")
+      end
+
+      it 'includes attachments' do
+        expect(transcript.messages[1].attachments.first).to eq("Discourse can now be integrated with Mattermost! - @david")
+      end
+
+      it 'can generate URL' do
+        expect(transcript.messages.first.url).to eq("https://slack.com/archives/G1234/p1501093331439776")
+      end
+
+      it 'gives correct first and last messages' do
+        expect(transcript.first_message_number).to eq(0)
+        expect(transcript.last_message_number).to eq(transcript.messages.length - 1)
+
+        expect(transcript.first_message.ts).to eq('1501093331.439776')
+        expect(transcript.last_message.ts).to eq('1501801665.062694')
+      end
+
+      it 'can change first and last messages by index' do
+        expect(transcript.set_first_message_by_index(999)).to be_falsey
+        expect(transcript.set_first_message_by_index(1)).to be_truthy
+
+        expect(transcript.set_last_message_by_index(-2)).to be_truthy
+
+        expect(transcript.first_message.ts).to eq('1501615820.949638')
+        expect(transcript.last_message.ts).to eq('1501801643.056375')
+      end
+
+      it 'can change first and last messages by ts' do
+        expect(transcript.set_first_message_by_ts('blah')).to be_falsey
+        expect(transcript.set_first_message_by_ts('1501615820.949638')).to be_truthy
+
+        expect(transcript.set_last_message_by_ts('1501801629.052212')).to be_truthy
+
+        expect(transcript.first_message_number).to eq(1)
+        expect(transcript.last_message_number).to eq(2)
+      end
+
+      it 'can guess the first message' do
+        expect(transcript.guess_first_message(skip_messages: 1)).to eq(true)
+        expect(transcript.first_message.ts).to eq('1501801629.052212')
+      end
+
+      it 'handles usernames correctly' do
+        expect(transcript.first_message.username).to eq('awesomeguy') # Normal user
+        expect(transcript.messages[2].username).to eq(nil) # Unknown normal user
+        expect(transcript.messages[1].username).to eq('Test Community') # Bot user
+      end
+
+      it 'handles avatars correctly' do
+        expect(transcript.first_message.avatar).to eq("https://example.com/avatar") # Normal user
+        expect(transcript.messages[1].avatar).to eq(nil) # Bot user
+      end
+
+      it 'creates a transcript correctly' do
+        transcript.set_last_message_by_index(1)
+
+        text = transcript.build_transcript
+
+        # Rubocop doesn't like this, but we really do need trailing whitespace in the string
+        # rubocop:disable TrailingWhitespace
+        expected = <<~END
+        [quote]
+        [**View in #general on Slack**](https://slack.com/archives/G1234/p1501093331439776)
+
+        ![awesomeguy] **@awesomeguy:** Let’s try some **bold text**
+
+        **@Test Community:** 
+        > Discourse can now be integrated with Mattermost! - @david
+
+        [/quote]
+
+        [awesomeguy]: https://example.com/avatar
+        END
+        # rubocop:enable TrailingWhitespace
+
+        expect(text).to eq(expected)
+      end
+
+      it 'creates the slack UI correctly' do
+        transcript.set_last_message_by_index(1)
+        ui = transcript.build_slack_ui
+
+        first_ui = ui[:attachments][0]
+        last_ui = ui[:attachments][1]
+
+        # The callback IDs are used to keep track of what the other option is
+        expect(first_ui[:callback_id]).to eq(transcript.last_message.ts)
+        expect(last_ui[:callback_id]).to eq(transcript.first_message.ts)
+
+        # The timestamps should match up to the actual messages
+        expect(first_ui[:ts]).to eq(transcript.first_message.ts)
+        expect(last_ui[:ts]).to eq(transcript.last_message.ts)
+      end
+    end
+  end
+end