Refactor transcript posting

lib/discourse_chat/provider/slack/slack_command_controller.rb

@@ -66,12 +66,17 @@ 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)
+      return error_message unless transcript.load_user_data
+      return error_message unless transcript.load_chat_history(slack_channel_id: slack_channel_id)
+
+      if first_message_ts
+        return error_message unless transcript.set_first_message_by_ts(first_message_ts)
+      else
+        return error_message unless transcript.set_first_message_by_index(-requested_messages)
+      end
 
       return transcript.build_slack_ui
 
@@ -92,16 +97,16 @@ 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]}")
+      return error_message unless transcript.load_user_data
+      return error_message unless transcript.load_chat_history(slack_channel_id: json[:channel][:id])
 
-      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?

lib/discourse_chat/provider/slack/slack_transcript_helper.rb

@@ -84,37 +84,50 @@ module DiscourseChat::Provider::SlackProvider
   class SlackTranscript
     attr_reader :users, :channel_id
 
-    def initialize(raw_history:, raw_users:, channel_id:, channel_name:, requested_messages: nil, first_message_ts: nil, last_message_ts: nil)
-
-      requested_messages ||= 10
-
-      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
-
-        # 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
-      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
-
-      @first_message_index = @messages.index(@first_message)
-      @last_message_index = @messages.index(@last_message)
-
-      @users = raw_users['members']
-      @channel_id = channel_id
+    def initialize(channel_name:)
       @channel_name = channel_name
+
+      @first_message_index = 0
+      @last_message_index = -1 # We can use negative array indicies to select the last message - fancy!
+    end
+
+    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
+
+    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
+
+    def first_message
+      return @messages[@first_message_index]
+    end
+
+    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 +175,41 @@ 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 +219,7 @@ 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 +229,12 @@ 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(slack_channel_id:, count: 500)
       http = Net::HTTP.new("slack.com", 443)
       http.use_ssl = true
 
@@ -236,21 +251,17 @@ 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