#!/usr/bin/env ruby
require 'gtk2'
require 'gtruby'
require 'etc'

TMPFILENAME = "/tmp/tmp.png"
RCFILENAME = "#{Etc.getpwuid.dir}/.quickgtkrc"

(stylefile, gff3file) = ARGV

def save_position(seqid, from, to)
  File.open(RCFILENAME, "w+") do |f|
    f.write("#{seqid}\t#{from}\t#{to}")
  end
end
def get_position
  begin
    File.open(RCFILENAME) do |f|
      vals = f.read.split("\t")
      return [vals[0], vals[1].to_f, vals[2].to_f]
    end
  rescue
    return [nil, 0, 10000]
  end
end

# load style file
style = GT::Style.new()
style.load_file(stylefile)
# create feature index
feature_index = GT::FeatureIndexMemory.new()
# add GFF3 file to index
feature_index.add_gff3file(gff3file)

@trackselector = Proc.new { |block, data|
  if block.get_type == "LTRHit"
    "LTR retrotransposon from Ensembl"
  elsif block.get_type == "RR_tract"
    "PPT"
  elsif block.get_type == "primer_binding_site"
    "PBS"
  else
    block.get_type
  end
}

def refresh_pic(seqid, from, to, feature_index, style)
  if seqid.nil? then
    seqid = feature_index.get_first_seqid()
  end
  if from.nil? or to.nil? then
    range = feature_index.get_range_for_seqid(seqid)
  else
    range = GT::Range.malloc
    range.start = from
    range.end = to
  end
  diagram = GT::Diagram.from_index(feature_index, seqid, range, style)
  diagram.set_track_selector_func(@trackselector)
  layout = GT::Layout.new(diagram, 1000, style)
  diagram.release_track_selector_func
  canvas = GT::CanvasCairoFile.new(style, 1000, layout.get_height, nil)
  layout.sketch(canvas)
  canvas.to_file(TMPFILENAME)
end

window = Gtk::Window.new
window.set_size_request(1000, -1)

window.title = "quick gtk browser"
window.signal_connect('delete_event') { false }
window.border_width = 10

startseqid, startfrom, startto = get_position
seqids = feature_index.get_seqids
if startseqid.nil? then
  startseqid = seqids[0]
end
refresh_pic(startseqid, startfrom, startto, feature_index, style)
image = Gtk::Image.new(TMPFILENAME)

vbox = Gtk::VBox.new(false, 0)
hbox = Gtk::HBox.new(false, 0)
vbox.pack_start(hbox, false, false, 0)
vbox.pack_start_defaults(image)

seqidbox = Gtk::ComboBox.new
seqids.each do |seqid|
  seqidbox.append_text(seqid)
end
seqidbox.active=seqids.index(startseqid)

frombox = Gtk::SpinButton.new(0.0, 100000000.0, 1.0)
tobox = Gtk::SpinButton.new(0.0, 100000000.0, 1.0)
frombox.value = startfrom.to_f
tobox.value = startto.to_f
back_button = Gtk::Button.new(Gtk::Stock::GO_BACK)
fwd_button = Gtk::Button.new(Gtk::Stock::GO_FORWARD)
go_button = Gtk::Button.new("Go")
[seqidbox, back_button, frombox, tobox, fwd_button, go_button].each do |i|
  hbox.pack_start_defaults(i)
end
go_button.signal_connect('clicked') do
  refresh_pic(seqidbox.active_text, frombox.text.to_i, tobox.text.to_i, feature_index, style)
  image.set(TMPFILENAME)
end
back_button.signal_connect('clicked') do
  displacement = tobox.text.to_i - frombox.text.to_i
  frombox.value = (frombox.text.to_i - displacement).to_f
  tobox.value = (tobox.text.to_i - displacement).to_f
  refresh_pic(seqidbox.active_text, frombox.text.to_i, tobox.text.to_i, \
              feature_index, style)
  image.set(TMPFILENAME)
end
fwd_button.signal_connect('clicked') do
  displacement = tobox.text.to_i - frombox.text.to_i
  frombox.value = (frombox.text.to_i + displacement).to_f
  tobox.value = (tobox.text.to_i + displacement).to_f
  refresh_pic(seqidbox.active_text, frombox.value.to_i, tobox.value.to_i, \
              feature_index, style)
  image.set(TMPFILENAME)
end

window.add(vbox)
window.show_all
window.signal_connect('destroy') do
  save_position(seqidbox.active_text, frombox.value.to_i, tobox.value.to_i)
  Gtk.main_quit
end

Gtk.main