diff --git a/lib/github_changelog_generator/generator/generator.rb b/lib/github_changelog_generator/generator/generator.rb
index 95bc165..1799958 100644
--- a/lib/github_changelog_generator/generator/generator.rb
+++ b/lib/github_changelog_generator/generator/generator.rb
@@ -1,6 +1,7 @@
 require "github_changelog_generator/fetcher"
-require_relative "generator_processor"
+require_relative "generator_generation"
 require_relative "generator_fetcher"
+require_relative "generator_processor"
 
 module GitHubChangelogGenerator
   # Default error for ChangelogGenerator
@@ -33,30 +34,6 @@ module GitHubChangelogGenerator
       detect_actual_closed_dates
     end
 
-    # Parse issue and generate single line formatted issue line.
-    #
-    # Example output:
-    # - Add coveralls integration [\#223](https://github.com/skywinder/github-changelog-generator/pull/223) ([skywinder](https://github.com/skywinder))
-    #
-    # @param [Hash] issue Fetched issue from GitHub
-    # @return [String] Markdown-formatted single issue
-    def get_string_for_issue(issue)
-      encapsulated_title = encapsulate_string issue[:title]
-
-      title_with_number = "#{encapsulated_title} [\\##{issue[:number]}](#{issue.html_url})"
-
-      unless issue.pull_request.nil?
-        if @options[:author]
-          if issue.user.nil?
-            title_with_number += " ({Null user})"
-          else
-            title_with_number += " ([#{issue.user.login}](#{issue.user.html_url}))"
-          end
-        end
-      end
-      title_with_number
-    end
-
     # Encapsulate characters to make markdown look as expected.
     #
     # @param [String] string
@@ -72,278 +49,6 @@ module GitHubChangelogGenerator
       string
     end
 
-    # Main function to start change log generation
-    #
-    # @return [String] Generated change log file
-    def compound_changelog
-      log = "# Change Log\n\n"
-
-      if @options[:unreleased_only]
-        log += generate_log_between_tags(all_tags[0], nil)
-      elsif @options[:tag1] && @options[:tag2]
-        tag1 = @options[:tag1]
-        tag2 = @options[:tag2]
-        tags_strings = []
-        all_tags.each { |x| tags_strings.push(x["name"]) }
-
-        if tags_strings.include?(tag1)
-          if tags_strings.include?(tag2)
-            to_a = tags_strings.map.with_index.to_a
-            hash = Hash[to_a]
-            index1 = hash[tag1]
-            index2 = hash[tag2]
-            log += generate_log_between_tags(all_tags[index1], all_tags[index2])
-          else
-            fail ChangelogGeneratorError, "Can't find tag #{tag2} -> exit".red
-          end
-        else
-          fail ChangelogGeneratorError, "Can't find tag #{tag1} -> exit".red
-        end
-      else
-        log += generate_log_for_all_tags
-      end
-
-      log += "\n\n\\* *This Change Log was automatically generated by [github_changelog_generator](https://github.com/skywinder/Github-Changelog-Generator)*"
-      @log = log
-      @log = log
-    end
-
-    # Async fetching of all tags dates
-    def fetch_tags_dates
-      print "Fetching tag dates...\r" if @options[:verbose]
-
-      # Async fetching tags:
-      threads = []
-      i = 0
-      all = @all_tags.count
-      @all_tags.each do |tag|
-        threads << Thread.new do
-          @fetcher.get_time_of_tag(tag)
-          if @options[:verbose]
-            print "Fetching tags dates: #{i + 1}/#{all}\r"
-            i += 1
-          end
-        end
-      end
-
-      print "                                 \r"
-
-      threads.each(&:join)
-
-      puts "Fetching tags dates: #{i}" if @options[:verbose]
-    end
-
-    # Return tags after filtering tags in lists provided by option: --between-tags & --exclude-tags
-    #
-    # @return [Array]
-    def get_filtered_tags
-      all_tags = @fetcher.get_all_tags
-      filtered_tags = []
-      if @options[:between_tags]
-        @options[:between_tags].each do |tag|
-          unless all_tags.include? tag
-            puts "Warning: can't find tag #{tag}, specified with --between-tags option.".yellow
-          end
-        end
-        filtered_tags = all_tags.select { |tag| @options[:between_tags].include? tag }
-      end
-      filtered_tags
-    end
-
-    def detect_actual_closed_dates
-      print "Fetching closed dates for issues...\r" if @options[:verbose]
-
-      threads = []
-
-      @issues.each do |issue|
-        threads << Thread.new do
-          find_closed_date_by_commit(issue)
-        end
-      end
-
-      @pull_requests.each do |pull_request|
-        threads << Thread.new do
-          find_closed_date_by_commit(pull_request)
-        end
-      end
-      threads.each(&:join)
-
-      puts "Fetching closed dates for issues: Done!" if @options[:verbose]
-    end
-
-    # Fill :actual_date parameter of specified issue by closed date of the commit, it it was closed by commit.
-    # @param [Hash] issue
-    def find_closed_date_by_commit(issue)
-      unless issue["events"].nil?
-        # if it's PR -> then find "merged event", in case of usual issue -> fond closed date
-        compare_string = issue[:merged_at].nil? ? "closed" : "merged"
-        # reverse! - to find latest closed event. (event goes in date order)
-        issue["events"].reverse!.each do |event|
-          if event[:event].eql? compare_string
-            if event[:commit_id].nil?
-              issue[:actual_date] = issue[:closed_at]
-            else
-              begin
-                commit = @fetcher.fetch_commit(event)
-                issue[:actual_date] = commit[:author][:date]
-              rescue
-                puts "Warning: Can't fetch commit #{event[:commit_id]}. It is probably referenced from another repo.".yellow
-                issue[:actual_date] = issue[:closed_at]
-              end
-            end
-            break
-          end
-        end
-      end
-      # TODO: assert issues, that remain without 'actual_date' hash for some reason.
-    end
-
-    def print_json(json)
-      puts JSON.pretty_generate(json)
-    end
-
-    # This method fetches missing params for PR and filter them by specified options
-    # It include add all PR's with labels from @options[:include_labels] array
-    # And exclude all from :exclude_labels array.
-    # @return [Array] filtered PR's
-    def get_filtered_pull_requests
-      filter_merged_pull_requests
-
-      filtered_pull_requests = include_issues_by_labels(@pull_requests)
-
-      filtered_pull_requests = exclude_issues_by_labels(filtered_pull_requests)
-
-      if @options[:verbose]
-        puts "Filtered pull requests: #{filtered_pull_requests.count}"
-      end
-
-      filtered_pull_requests
-    end
-
-    # This method filter only merged PR and
-    # fetch missing required attributes for pull requests
-    # :merged_at - is a date, when issue PR was merged.
-    # More correct to use merged date, rather than closed date.
-    def filter_merged_pull_requests
-      print "Fetching merged dates...\r" if @options[:verbose]
-      pull_requests = @fetcher.fetch_closed_pull_requests
-
-      @pull_requests.each do |pr|
-        fetched_pr = pull_requests.find do |fpr|
-          fpr.number == pr.number
-        end
-        pr[:merged_at] = fetched_pr[:merged_at]
-        pull_requests.delete(fetched_pr)
-      end
-
-      @pull_requests.select! do |pr|
-        !pr[:merged_at].nil?
-      end
-    end
-
-    # Include issues with labels, specified in :include_labels
-    # @param [Array] issues to filter
-    # @return [Array] filtered array of issues
-    def include_issues_by_labels(issues)
-      filtered_issues = @options[:include_labels].nil? ? issues : issues.select do |issue|
-        labels = issue.labels.map(&:name) & @options[:include_labels]
-        (labels).any?
-      end
-
-      if @options[:add_issues_wo_labels]
-        issues_wo_labels = issues.select do |issue|
-          !issue.labels.map(&:name).any?
-        end
-        filtered_issues |= issues_wo_labels
-      end
-      filtered_issues
-    end
-
-    # delete all labels with labels from @options[:exclude_labels] array
-    # @param [Array] issues
-    # @return [Array] filtered array
-    def exclude_issues_by_labels(issues)
-      unless @options[:exclude_labels].nil?
-        issues = issues.select do |issue|
-          var = issue.labels.map(&:name) & @options[:exclude_labels]
-          !(var).any?
-        end
-      end
-      issues
-    end
-
-    def filter_by_milestone(filtered_issues, newer_tag_name, src_array)
-      filtered_issues.select! do |issue|
-        # leave issues without milestones
-        if issue.milestone.nil?
-          true
-        else
-          # check, that this milestone in tag list:
-          @all_tags.find { |tag| tag.name == issue.milestone.title }.nil?
-        end
-      end
-      unless newer_tag_name.nil?
-
-        # add missed issues (according milestones)
-        issues_to_add = src_array.select do |issue|
-          if issue.milestone.nil?
-            false
-          else
-            # check, that this milestone in tag list:
-            milestone_is_tag = @all_tags.find do |tag|
-              tag.name == issue.milestone.title
-            end
-
-            if milestone_is_tag.nil?
-              false
-            else
-              issue.milestone.title == newer_tag_name
-            end
-          end
-        end
-
-        filtered_issues |= issues_to_add
-      end
-      filtered_issues
-    end
-
-    # Method filter issues, that belong only specified tag range
-    # @param [Array] array of issues to filter
-    # @param [Symbol] hash_key key of date value default is :actual_date
-    # @param [String] older_tag all issues before this tag date will be excluded. May be nil, if it's first tag
-    # @param [String] newer_tag all issue after this tag will be excluded. May be nil for unreleased section
-    # @return [Array] filtered issues
-    def delete_by_time(array, hash_key = :actual_date, older_tag = nil, newer_tag = nil)
-      fail ChangelogGeneratorError, "At least one of the tags should be not nil!".red if older_tag.nil? && newer_tag.nil?
-
-      newer_tag_time = newer_tag && @fetcher.get_time_of_tag(newer_tag)
-      older_tag_time = older_tag && @fetcher.get_time_of_tag(older_tag)
-
-      array.select do |req|
-        if req[hash_key]
-          t = Time.parse(req[hash_key]).utc
-
-          if older_tag_time.nil?
-            tag_in_range_old = true
-          else
-            tag_in_range_old = t > older_tag_time
-          end
-
-          if newer_tag_time.nil?
-            tag_in_range_new = true
-          else
-            tag_in_range_new = t <= newer_tag_time
-          end
-
-          tag_in_range = (tag_in_range_old) && (tag_in_range_new)
-
-          tag_in_range
-        else
-          false
-        end
-      end
-    end
-
     # Generates log for section with header and body
     #
     # @param [Array] pull_requests List or PR's in new section
@@ -411,17 +116,5 @@ module GitHubChangelogGenerator
       end
       [bugs_a, enhancement_a, issues_a]
     end
-
-    # Filter issues according labels
-    # @return [Array] Filtered issues
-    def get_filtered_issues
-      filtered_issues = include_issues_by_labels(@issues)
-
-      filtered_issues = exclude_issues_by_labels(filtered_issues)
-
-      puts "Filtered issues: #{filtered_issues.count}" if @options[:verbose]
-
-      filtered_issues
-    end
   end
 end
diff --git a/lib/github_changelog_generator/generator/generator_fetcher.rb b/lib/github_changelog_generator/generator/generator_fetcher.rb
index 45ec1a2..bf7a2ef 100644
--- a/lib/github_changelog_generator/generator/generator_fetcher.rb
+++ b/lib/github_changelog_generator/generator/generator_fetcher.rb
@@ -10,5 +10,79 @@ module GitHubChangelogGenerator
       # Async fetching events:
       @fetcher.fetch_events_async(@issues + @pull_requests)
     end
+
+    # Async fetching of all tags dates
+    def fetch_tags_dates
+      print "Fetching tag dates...\r" if @options[:verbose]
+
+      # Async fetching tags:
+      threads = []
+      i = 0
+      all = @all_tags.count
+      @all_tags.each do |tag|
+        threads << Thread.new do
+          @fetcher.get_time_of_tag(tag)
+          if @options[:verbose]
+            print "Fetching tags dates: #{i + 1}/#{all}\r"
+            i += 1
+          end
+        end
+      end
+
+      print "                                 \r"
+
+      threads.each(&:join)
+
+      puts "Fetching tags dates: #{i}" if @options[:verbose]
+    end
+
+    # Find correct closed dates, if issues was closed by commits
+    def detect_actual_closed_dates
+      print "Fetching closed dates for issues...\r" if @options[:verbose]
+
+      threads = []
+
+      @issues.each do |issue|
+        threads << Thread.new do
+          find_closed_date_by_commit(issue)
+        end
+      end
+
+      @pull_requests.each do |pull_request|
+        threads << Thread.new do
+          find_closed_date_by_commit(pull_request)
+        end
+      end
+      threads.each(&:join)
+
+      puts "Fetching closed dates for issues: Done!" if @options[:verbose]
+    end
+
+    # Fill :actual_date parameter of specified issue by closed date of the commit, it it was closed by commit.
+    # @param [Hash] issue
+    def find_closed_date_by_commit(issue)
+      unless issue["events"].nil?
+        # if it's PR -> then find "merged event", in case of usual issue -> fond closed date
+        compare_string = issue[:merged_at].nil? ? "closed" : "merged"
+        # reverse! - to find latest closed event. (event goes in date order)
+        issue["events"].reverse!.each do |event|
+          if event[:event].eql? compare_string
+            if event[:commit_id].nil?
+              issue[:actual_date] = issue[:closed_at]
+            else
+              begin
+                commit = @fetcher.fetch_commit(event)
+                issue[:actual_date] = commit[:author][:date]
+              rescue
+                puts "Warning: Can't fetch commit #{event[:commit_id]}. It is probably referenced from another repo.".yellow
+                issue[:actual_date] = issue[:closed_at]
+              end
+            end
+            break
+          end
+        end
+      end
+      # TODO: assert issues, that remain without 'actual_date' hash for some reason.
+    end
   end
 end
diff --git a/lib/github_changelog_generator/generator/generator_generation.rb b/lib/github_changelog_generator/generator/generator_generation.rb
new file mode 100644
index 0000000..c5227d9
--- /dev/null
+++ b/lib/github_changelog_generator/generator/generator_generation.rb
@@ -0,0 +1,161 @@
+module GitHubChangelogGenerator
+  class Generator
+    # Main function to start change log generation
+    #
+    # @return [String] Generated change log file
+    def compound_changelog
+      log = "# Change Log\n\n"
+
+      if @options[:unreleased_only]
+        log += generate_log_between_tags(all_tags[0], nil)
+      elsif @options[:tag1] && @options[:tag2]
+        tag1 = @options[:tag1]
+        tag2 = @options[:tag2]
+        tags_strings = []
+        all_tags.each { |x| tags_strings.push(x["name"]) }
+
+        if tags_strings.include?(tag1)
+          if tags_strings.include?(tag2)
+            to_a = tags_strings.map.with_index.to_a
+            hash = Hash[to_a]
+            index1 = hash[tag1]
+            index2 = hash[tag2]
+            log += generate_log_between_tags(all_tags[index1], all_tags[index2])
+          else
+            fail ChangelogGeneratorError, "Can't find tag #{tag2} -> exit".red
+          end
+        else
+          fail ChangelogGeneratorError, "Can't find tag #{tag1} -> exit".red
+        end
+      else
+        log += generate_log_for_all_tags
+      end
+
+      log += "\n\n\\* *This Change Log was automatically generated by [github_changelog_generator](https://github.com/skywinder/Github-Changelog-Generator)*"
+      @log = log
+      @log = log
+    end
+
+    # @param [Array] issues List of issues on sub-section
+    # @param [String] prefix Nae of sub-section
+    # @return [String] Generate ready-to-go sub-section
+    def generate_sub_section(issues, prefix)
+      log = ""
+
+      log += "#{prefix}\n\n" if options[:simple_list] != true && issues.any?
+
+      if issues.any?
+        issues.each do |issue|
+          merge_string = get_string_for_issue(issue)
+          log += "- #{merge_string}\n\n"
+        end
+      end
+      log
+    end
+
+    # It generate one header for section with specific parameters.
+    #
+    # @param [String] newer_tag_name - name of newer tag
+    # @param [String] newer_tag_link - used for links. Could be same as #newer_tag_name or some specific value, like HEAD
+    # @param [Time] newer_tag_time - time, when newer tag created
+    # @param [String] older_tag_link - tag name, used for links.
+    # @param [String] project_url - url for current project.
+    # @return [String] - Generate one ready-to-add section.
+    def generate_header(newer_tag_name, newer_tag_link, newer_tag_time, older_tag_link, project_url)
+      log = ""
+
+      # Generate date string:
+      time_string = newer_tag_time.strftime @options[:dateformat]
+
+      # Generate tag name and link
+      if newer_tag_name.equal? @options[:unreleased_label]
+        log += "## [#{newer_tag_name}](#{project_url}/tree/#{newer_tag_link})\n\n"
+      else
+        log += "## [#{newer_tag_name}](#{project_url}/tree/#{newer_tag_link}) (#{time_string})\n\n"
+      end
+
+      if @options[:compare_link] && older_tag_link
+        # Generate compare link
+        log += "[Full Changelog](#{project_url}/compare/#{older_tag_link}...#{newer_tag_link})\n\n"
+      end
+
+      log
+    end
+
+    # Generate log only between 2 specified tags
+    # @param [String] older_tag all issues before this tag date will be excluded. May be nil, if it's first tag
+    # @param [String] newer_tag all issue after this tag will be excluded. May be nil for unreleased section
+    def generate_log_between_tags(older_tag, newer_tag)
+      filtered_pull_requests = delete_by_time(@pull_requests, :actual_date, older_tag, newer_tag)
+      filtered_issues = delete_by_time(@issues, :actual_date, older_tag, newer_tag)
+
+      newer_tag_name = newer_tag.nil? ? nil : newer_tag["name"]
+      older_tag_name = older_tag.nil? ? nil : older_tag["name"]
+
+      if @options[:filter_issues_by_milestone]
+        # delete excess irrelevant issues (according milestones). Issue #22.
+        filtered_issues = filter_by_milestone(filtered_issues, newer_tag_name, @issues)
+        filtered_pull_requests = filter_by_milestone(filtered_pull_requests, newer_tag_name, @pull_requests)
+      end
+
+      if newer_tag.nil? && filtered_issues.empty? && filtered_pull_requests.empty?
+        # do not generate empty unreleased section
+        return ""
+      end
+
+      create_log(filtered_pull_requests, filtered_issues, newer_tag, older_tag_name)
+    end
+
+    # The full cycle of generation for whole project
+    # @return [String] The complete change log
+    def generate_log_for_all_tags
+      fetch_tags_dates
+
+      puts "Sorting tags..." if @options[:verbose]
+
+      @all_tags.sort_by! { |x| @fetcher.get_time_of_tag(x) }.reverse!
+
+      puts "Generating log..." if @options[:verbose]
+
+      log = ""
+
+      if @options[:unreleased] && @all_tags.count != 0
+        unreleased_log = generate_log_between_tags(all_tags[0], nil)
+        log += unreleased_log if unreleased_log
+      end
+
+      (1...all_tags.size).each do |index|
+        log += generate_log_between_tags(all_tags[index], all_tags[index - 1])
+      end
+      if @all_tags.count != 0
+        log += generate_log_between_tags(nil, all_tags.last)
+      end
+
+      log
+    end
+
+    # Parse issue and generate single line formatted issue line.
+    #
+    # Example output:
+    # - Add coveralls integration [\#223](https://github.com/skywinder/github-changelog-generator/pull/223) ([skywinder](https://github.com/skywinder))
+    #
+    # @param [Hash] issue Fetched issue from GitHub
+    # @return [String] Markdown-formatted single issue
+    def get_string_for_issue(issue)
+      encapsulated_title = encapsulate_string issue[:title]
+
+      title_with_number = "#{encapsulated_title} [\\##{issue[:number]}](#{issue.html_url})"
+
+      unless issue.pull_request.nil?
+        if @options[:author]
+          if issue.user.nil?
+            title_with_number += " ({Null user})"
+          else
+            title_with_number += " ([#{issue.user.login}](#{issue.user.html_url}))"
+          end
+        end
+      end
+      title_with_number
+    end
+  end
+end
diff --git a/lib/github_changelog_generator/generator/generator_processor.rb b/lib/github_changelog_generator/generator/generator_processor.rb
index 62a8747..55e736c 100644
--- a/lib/github_changelog_generator/generator/generator_processor.rb
+++ b/lib/github_changelog_generator/generator/generator_processor.rb
@@ -1,101 +1,174 @@
 module GitHubChangelogGenerator
   class Generator
-    # @param [Array] issues List of issues on sub-section
-    # @param [String] prefix Nae of sub-section
-    # @return [String] Generate ready-to-go sub-section
-    def generate_sub_section(issues, prefix)
-      log = ""
-
-      log += "#{prefix}\n\n" if options[:simple_list] != true && issues.any?
-
-      if issues.any?
-        issues.each do |issue|
-          merge_string = get_string_for_issue(issue)
-          log += "- #{merge_string}\n\n"
+    # delete all labels with labels from @options[:exclude_labels] array
+    # @param [Array] issues
+    # @return [Array] filtered array
+    def exclude_issues_by_labels(issues)
+      unless @options[:exclude_labels].nil?
+        issues = issues.select do |issue|
+          var = issue.labels.map(&:name) & @options[:exclude_labels]
+          !(var).any?
         end
       end
-      log
+      issues
     end
 
-    # It generate one header for section with specific parameters.
-    #
-    # @param [String] newer_tag_name - name of newer tag
-    # @param [String] newer_tag_link - used for links. Could be same as #newer_tag_name or some specific value, like HEAD
-    # @param [Time] newer_tag_time - time, when newer tag created
-    # @param [String] older_tag_link - tag name, used for links.
-    # @param [String] project_url - url for current project.
-    # @return [String] - Generate one ready-to-add section.
-    def generate_header(newer_tag_name, newer_tag_link, newer_tag_time, older_tag_link, project_url)
-      log = ""
-
-      # Generate date string:
-      time_string = newer_tag_time.strftime @options[:dateformat]
-
-      # Generate tag name and link
-      if newer_tag_name.equal? @options[:unreleased_label]
-        log += "## [#{newer_tag_name}](#{project_url}/tree/#{newer_tag_link})\n\n"
-      else
-        log += "## [#{newer_tag_name}](#{project_url}/tree/#{newer_tag_link}) (#{time_string})\n\n"
+    def filter_by_milestone(filtered_issues, newer_tag_name, src_array)
+      filtered_issues.select! do |issue|
+        # leave issues without milestones
+        if issue.milestone.nil?
+          true
+        else
+          # check, that this milestone in tag list:
+          @all_tags.find { |tag| tag.name == issue.milestone.title }.nil?
+        end
       end
+      unless newer_tag_name.nil?
 
-      if @options[:compare_link] && older_tag_link
-        # Generate compare link
-        log += "[Full Changelog](#{project_url}/compare/#{older_tag_link}...#{newer_tag_link})\n\n"
+        # add missed issues (according milestones)
+        issues_to_add = src_array.select do |issue|
+          if issue.milestone.nil?
+            false
+          else
+            # check, that this milestone in tag list:
+            milestone_is_tag = @all_tags.find do |tag|
+              tag.name == issue.milestone.title
+            end
+
+            if milestone_is_tag.nil?
+              false
+            else
+              issue.milestone.title == newer_tag_name
+            end
+          end
+        end
+
+        filtered_issues |= issues_to_add
       end
-
-      log
+      filtered_issues
     end
 
-    # Generate log only between 2 specified tags
+    # Method filter issues, that belong only specified tag range
+    # @param [Array] array of issues to filter
+    # @param [Symbol] hash_key key of date value default is :actual_date
     # @param [String] older_tag all issues before this tag date will be excluded. May be nil, if it's first tag
     # @param [String] newer_tag all issue after this tag will be excluded. May be nil for unreleased section
-    def generate_log_between_tags(older_tag, newer_tag)
-      filtered_pull_requests = delete_by_time(@pull_requests, :actual_date, older_tag, newer_tag)
-      filtered_issues = delete_by_time(@issues, :actual_date, older_tag, newer_tag)
+    # @return [Array] filtered issues
+    def delete_by_time(array, hash_key = :actual_date, older_tag = nil, newer_tag = nil)
+      fail ChangelogGeneratorError, "At least one of the tags should be not nil!".red if older_tag.nil? && newer_tag.nil?
 
-      newer_tag_name = newer_tag.nil? ? nil : newer_tag["name"]
-      older_tag_name = older_tag.nil? ? nil : older_tag["name"]
+      newer_tag_time = newer_tag && @fetcher.get_time_of_tag(newer_tag)
+      older_tag_time = older_tag && @fetcher.get_time_of_tag(older_tag)
 
-      if @options[:filter_issues_by_milestone]
-        # delete excess irrelevant issues (according milestones). Issue #22.
-        filtered_issues = filter_by_milestone(filtered_issues, newer_tag_name, @issues)
-        filtered_pull_requests = filter_by_milestone(filtered_pull_requests, newer_tag_name, @pull_requests)
+      array.select do |req|
+        if req[hash_key]
+          t = Time.parse(req[hash_key]).utc
+
+          if older_tag_time.nil?
+            tag_in_range_old = true
+          else
+            tag_in_range_old = t > older_tag_time
+          end
+
+          if newer_tag_time.nil?
+            tag_in_range_new = true
+          else
+            tag_in_range_new = t <= newer_tag_time
+          end
+
+          tag_in_range = (tag_in_range_old) && (tag_in_range_new)
+
+          tag_in_range
+        else
+          false
+        end
       end
-
-      if newer_tag.nil? && filtered_issues.empty? && filtered_pull_requests.empty?
-        # do not generate empty unreleased section
-        return ""
-      end
-
-      create_log(filtered_pull_requests, filtered_issues, newer_tag, older_tag_name)
     end
 
-    # The full cycle of generation for whole project
-    # @return [String] The complete change log
-    def generate_log_for_all_tags
-      fetch_tags_dates
+    # This method fetches missing params for PR and filter them by specified options
+    # It include add all PR's with labels from @options[:include_labels] array
+    # And exclude all from :exclude_labels array.
+    # @return [Array] filtered PR's
+    def get_filtered_pull_requests
+      filter_merged_pull_requests
 
-      puts "Sorting tags..." if @options[:verbose]
+      filtered_pull_requests = include_issues_by_labels(@pull_requests)
 
-      @all_tags.sort_by! { |x| @fetcher.get_time_of_tag(x) }.reverse!
+      filtered_pull_requests = exclude_issues_by_labels(filtered_pull_requests)
 
-      puts "Generating log..." if @options[:verbose]
-
-      log = ""
-
-      if @options[:unreleased] && @all_tags.count != 0
-        unreleased_log = generate_log_between_tags(all_tags[0], nil)
-        log += unreleased_log if unreleased_log
+      if @options[:verbose]
+        puts "Filtered pull requests: #{filtered_pull_requests.count}"
       end
 
-      (1...all_tags.size).each do |index|
-        log += generate_log_between_tags(all_tags[index], all_tags[index - 1])
-      end
-      if @all_tags.count != 0
-        log += generate_log_between_tags(nil, all_tags.last)
+      filtered_pull_requests
+    end
+
+    # This method filter only merged PR and
+    # fetch missing required attributes for pull requests
+    # :merged_at - is a date, when issue PR was merged.
+    # More correct to use merged date, rather than closed date.
+    def filter_merged_pull_requests
+      print "Fetching merged dates...\r" if @options[:verbose]
+      pull_requests = @fetcher.fetch_closed_pull_requests
+
+      @pull_requests.each do |pr|
+        fetched_pr = pull_requests.find do |fpr|
+          fpr.number == pr.number
+        end
+        pr[:merged_at] = fetched_pr[:merged_at]
+        pull_requests.delete(fetched_pr)
       end
 
-      log
+      @pull_requests.select! do |pr|
+        !pr[:merged_at].nil?
+      end
+    end
+
+    # Include issues with labels, specified in :include_labels
+    # @param [Array] issues to filter
+    # @return [Array] filtered array of issues
+    def include_issues_by_labels(issues)
+      filtered_issues = @options[:include_labels].nil? ? issues : issues.select do |issue|
+        labels = issue.labels.map(&:name) & @options[:include_labels]
+        (labels).any?
+      end
+
+      if @options[:add_issues_wo_labels]
+        issues_wo_labels = issues.select do |issue|
+          !issue.labels.map(&:name).any?
+        end
+        filtered_issues |= issues_wo_labels
+      end
+      filtered_issues
+    end
+
+    # Return tags after filtering tags in lists provided by option: --between-tags & --exclude-tags
+    #
+    # @return [Array]
+    def get_filtered_tags
+      all_tags = @fetcher.get_all_tags
+      filtered_tags = []
+      if @options[:between_tags]
+        @options[:between_tags].each do |tag|
+          unless all_tags.include? tag
+            puts "Warning: can't find tag #{tag}, specified with --between-tags option.".yellow
+          end
+        end
+        filtered_tags = all_tags.select { |tag| @options[:between_tags].include? tag }
+      end
+      filtered_tags
+    end
+
+    # Filter issues according labels
+    # @return [Array] Filtered issues
+    def get_filtered_issues
+      filtered_issues = include_issues_by_labels(@issues)
+
+      filtered_issues = exclude_issues_by_labels(filtered_issues)
+
+      puts "Filtered issues: #{filtered_issues.count}" if @options[:verbose]
+
+      filtered_issues
     end
   end
 end