Refactor: rename module and class names.

* Module: Graph -> Network
* Class: JsonBuilder -> Graph

app/models/network/commit.rb

@@ -0,0 +1,39 @@
+require "grit"
+
+module Network
+  class Commit
+    include ActionView::Helpers::TagHelper
+
+    attr_accessor :time, :spaces, :refs, :parent_spaces
+
+    def initialize(commit)
+      @_commit = commit
+      @time = -1
+      @spaces = []
+      @parent_spaces = []
+    end
+
+    def method_missing(m, *args, &block)
+      @_commit.send(m, *args, &block)
+    end
+
+    def add_refs(ref_cache, repo)
+      if ref_cache.empty?
+        repo.refs.each do |ref|
+          ref_cache[ref.commit.id] ||= []
+          ref_cache[ref.commit.id] << ref
+        end
+      end
+      @refs = ref_cache[@_commit.id] if ref_cache.include?(@_commit.id)
+      @refs ||= []
+    end
+
+    def space
+      if @spaces.size > 0
+        @spaces.first
+      else
+        0
+      end
+    end
+  end
+end

app/models/network/graph.rb

@@ -0,0 +1,284 @@
+require "grit"
+
+module Network
+  class Graph
+    attr_accessor :days, :commits, :ref_cache, :repo
+
+    def self.max_count
+      @max_count ||= 650
+    end
+
+    def initialize project, ref, commit
+      @project = project
+      @ref = ref
+      @commit = commit
+      @repo = project.repo
+      @ref_cache = {}
+
+      @commits = collect_commits
+      @days = index_commits
+    end
+
+    protected
+
+    # Get commits from repository
+    #
+    def collect_commits
+
+      @commits = Grit::Commit.find_all(repo, nil, {date_order: true, max_count: self.class.max_count, skip: to_commit}).dup
+
+      # Decorate with app/models/commit.rb
+      @commits.map! { |commit| Commit.new(commit) }
+
+      # Decorate with app/model/network/commit.rb
+      @commits.map! { |commit| Network::Commit.new(commit) }
+
+      # add refs to each commit
+      @commits.each { |commit| commit.add_refs(ref_cache, repo) }
+
+      @commits
+    end
+
+    # Method is adding time and space on the
+    # list of commits. As well as returns date list
+    # corelated with time set on commits.
+    #
+    # @param [Array<Graph::Commit>] commits to index
+    #
+    # @return [Array<TimeDate>] list of commit dates corelated with time on commits
+    def index_commits
+      days, times = [], []
+      map = {}
+
+      commits.reverse.each_with_index do |c,i|
+        c.time = i
+        days[i] = c.committed_date
+        map[c.id] = c
+        times[i] = c
+      end
+
+      @_reserved = {}
+      days.each_index do |i|
+        @_reserved[i] = []
+      end
+
+      commits_sort_by_ref.each do |commit|
+        if map.include? commit.id then
+          place_chain(map[commit.id], map)
+        end
+      end
+
+      # find parent spaces for not overlap lines
+      times.each do |c|
+        c.parent_spaces.concat(find_free_parent_spaces(c, map, times))
+      end
+
+      days
+    end
+
+    # Skip count that the target commit is displayed in center.
+    def to_commit
+      commits = Grit::Commit.find_all(repo, nil, {date_order: true})
+      commit_index = commits.index do |c|
+        c.id == @commit.id
+      end
+
+      if commit_index && (self.class.max_count / 2 < commit_index) then
+        # get max index that commit is displayed in the center.
+        commit_index - self.class.max_count / 2
+      else
+        0
+      end
+    end
+
+    def commits_sort_by_ref
+      commits.sort do |a,b|
+        if include_ref?(a)
+          -1
+        elsif include_ref?(b)
+          1
+        else
+          b.committed_date <=> a.committed_date
+        end
+      end
+    end
+
+    def include_ref?(commit)
+      heads = commit.refs.select do |ref|
+        ref.is_a?(Grit::Head) or ref.is_a?(Grit::Remote) or ref.is_a?(Grit::Tag)
+      end
+
+      heads.map! do |head|
+        head.name
+      end
+
+      heads.include?(@ref)
+    end
+
+    def find_free_parent_spaces(commit, map, times)
+      spaces = []
+
+      commit.parents.each do |p|
+        if map.include?(p.id) then
+          parent = map[p.id]
+
+          range = if commit.time < parent.time then
+                    commit.time..parent.time
+                  else
+                    parent.time..commit.time
+                  end
+
+          space = if commit.space >= parent.space then
+                    find_free_parent_space(range, parent.space, -1, commit.space, times)
+                  else
+                    find_free_parent_space(range, commit.space, -1, parent.space, times)
+                  end
+
+          mark_reserved(range, space)
+          spaces << space
+        end
+      end
+
+      spaces
+    end
+
+    def find_free_parent_space(range, space_base, space_step, space_default, times)
+      if is_overlap?(range, times, space_default) then
+        find_free_space(range, space_step, space_base, space_default)
+      else
+        space_default
+      end
+    end
+
+    def is_overlap?(range, times, overlap_space)
+      range.each do |i|
+        if i != range.first &&
+          i != range.last &&
+          times[i].spaces.include?(overlap_space) then
+
+          return true;
+        end
+      end
+
+      false
+    end
+
+    # Add space mark on commit and its parents
+    #
+    # @param [Graph::Commit] the commit object.
+    # @param [Hash<String,Graph::Commit>] map of commits
+    def place_chain(commit, map, parent_time = nil)
+      leaves = take_left_leaves(commit, map)
+      if leaves.empty?
+        return
+      end
+
+      time_range = leaves.last.time..leaves.first.time
+      space_base = get_space_base(leaves, map)
+      space = find_free_space(time_range, 2, space_base)
+      leaves.each do |l|
+        l.spaces << space
+        # Also add space to parent
+        l.parents.each do |p|
+          if map.include?(p.id)
+            parent = map[p.id]
+            if parent.space > 0
+              parent.spaces << space
+            end
+          end
+        end
+      end
+
+      # and mark it as reserved
+      min_time = leaves.last.time
+      parents = leaves.last.parents.collect
+      parents.each do |p|
+        if map.include? p.id
+          parent = map[p.id]
+          if parent.time < min_time
+            min_time = parent.time
+          end
+        end
+      end
+
+      if parent_time.nil?
+        max_time = leaves.first.time
+      else
+        max_time = parent_time - 1
+      end
+      mark_reserved(min_time..max_time, space)
+
+      # Visit branching chains
+      leaves.each do |l|
+        parents = l.parents.collect.select{|p| map.include? p.id and map[p.id].space.zero?}
+        for p in parents
+          place_chain(map[p.id], map, l.time)
+        end
+      end
+    end
+
+    def get_space_base(leaves, map)
+      space_base = 1
+      if leaves.last.parents.size > 0
+        first_parent = leaves.last.parents.first
+        if map.include?(first_parent.id)
+          first_p = map[first_parent.id]
+          if first_p.space > 0
+            space_base = first_p.space
+          end
+        end
+      end
+      space_base
+    end
+
+    def mark_reserved(time_range, space)
+      for day in time_range
+        @_reserved[day].push(space)
+      end
+    end
+
+    def find_free_space(time_range, space_step, space_base = 1, space_default = nil)
+      space_default ||= space_base
+
+      reserved = []
+      for day in time_range
+        reserved += @_reserved[day]
+      end
+      reserved.uniq!
+
+      space = space_default
+      while reserved.include?(space) do
+        space += space_step
+        if space < space_base then
+          space_step *= -1
+          space = space_base + space_step
+        end
+      end
+
+      space
+    end
+
+    # Takes most left subtree branch of commits
+    # which don't have space mark yet.
+    #
+    # @param [Graph::Commit] the commit object.
+    # @param [Hash<String,Graph::Commit>] map of commits
+    #
+    # @return [Array<Graph::Commit>] list of branch commits
+    def take_left_leaves(commit, map)
+      leaves = []
+      leaves.push(commit) if commit.space.zero?
+
+      while true
+        return leaves if commit.parents.count.zero?
+        return leaves unless map.include? commit.parents.first.id
+
+        commit = map[commit.parents.first.id]
+
+        return leaves unless commit.space.zero?
+
+        leaves.push(commit)
+      end
+    end
+  end
+end