Class Gitlab::Graph::JsonBuilder < Object

# File lib/gitlab/graph/json_builder.rb, line 8
def self.max_count
  @max_count ||= 650
end

# File lib/gitlab/graph/json_builder.rb, line 12
def initialize project
  @project = project
  @repo = project.repo
  @ref_cache = {}

  @commits = collect_commits
  @days = index_commits
end

# File lib/gitlab/graph/json_builder.rb, line 21
def to_json(*args)
  {
    days: @days.compact.map { |d| [d.day, d.strftime("%b")] },
    commits: @commits.map(&:to_graph_hash)
  }.to_json(*args)
end

# File lib/gitlab/graph/json_builder.rb, line 148
def base_space(leaves, map)
  parents = []
  leaves.each do |l|
    parents.concat l.parents.collect.select{|p| map.include? p.id and map[p.id].space.nonzero?}
  end

  space = parents.map{|p| map[p.id].space}.max || 0
  space += 1
end

# File lib/gitlab/graph/json_builder.rb, line 32
def collect_commits
  @commits = Grit::Commit.find_all(repo, nil, {max_count: self.class.max_count}).dup

  # Decorate with app/models/commit.rb
  @commits.map! { |commit| ::Commit.new(commit) }

  # Decorate with lib/gitlab/graph/commit.rb
  @commits.map! { |commit| Gitlab::Graph::Commit.new(commit) }

  # add refs to each commit
  @commits.each { |commit| commit.add_refs(ref_cache, repo) }

  @commits
end

# File lib/gitlab/graph/json_builder.rb, line 135
def find_free_space(leaves, map)
  time_range = leaves.last.time..leaves.first.time
  reserved = []
  for day in time_range
    reserved += @_reserved[day]
  end
  space = base_space(leaves, map)
  while reserved.include? space do
    space += 1
  end
  space
end

# File lib/gitlab/graph/json_builder.rb, line 54
def index_commits
  days, heads = [], []
  map = {}

  commits.reverse.each_with_index do |c,i|
    c.time = i
    days[i] = c.committed_date
    map[c.id] = c
    heads += c.refs unless c.refs.nil?
  end

  heads.select!{|h| h.is_a? Grit::Head or h.is_a? Grit::Remote}
  # sort heads so the master is top and current branches are closer
  heads.sort! do |a,b|
    if a.name == "master"
      -1
    elsif b.name == "master"
      1
    else
      b.commit.committed_date <=> a.commit.committed_date
    end
  end

  @_reserved = {}
  days.each_index do |i|
    @_reserved[i] = []
  end

  heads.each do |h|
    if map.include? h.commit.id then
      place_chain(map[h.commit.id], map)
    end
  end

  days
end

# File lib/gitlab/graph/json_builder.rb, line 129
def mark_reserved(time_range, space)
  for day in time_range
    @_reserved[day].push(space)
  end
end

# File lib/gitlab/graph/json_builder.rb, line 95
def place_chain(commit, map, parent_time = nil)
  leaves = take_left_leaves(commit, map)
  if leaves.empty?
    return
  end
  space = find_free_space(leaves, map)
  leaves.each{|l| l.space = space}
  # 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

# File lib/gitlab/graph/json_builder.rb, line 165
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