gitg/libgitg/gitg-diff-view-hunk.vala

/*
 * This file is part of gitg
 *
 * Copyright (C) 2015 - Jesse van den Kieboom
 *
 * gitg is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * gitg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with gitg. If not, see <http://www.gnu.org/licenses/>.
 */

[GtkTemplate (ui = "/org/gnome/gitg/ui/gitg-diff-view-hunk.ui")]
class Gitg.DiffViewHunk : Gtk.Grid
{
	private Gtk.Label d_label_hunk;

	[GtkChild( name = "sourceview_hunk" )]
	private Gtk.SourceView d_sourceview_hunk;

	private string d_selection_category = "selection";

	public Ggit.DiffHunk hunk
	{
		get;
		construct set;
	}

	public Gee.ArrayList<Ggit.DiffLine> lines
	{
		get;
		construct set;
	}

	public bool handle_selection
	{
		get;
		construct set;
	}

	public DiffViewHunk(Ggit.DiffHunk hunk, Gee.ArrayList<Ggit.DiffLine> lines, bool handle_selection)
	{
		Object(hunk: hunk, lines: lines, handle_selection: handle_selection);
	}

	private uint d_added;

	public uint added
	{
		get { return d_added; }
	}

	private uint d_removed;

	public uint removed
	{
		get { return d_removed; }
	}

	public int maxlines
	{
		get; set;
	}

	public bool wrap
	{
		get { return d_sourceview_hunk.wrap_mode != Gtk.WrapMode.NONE; }
		set
		{
			if (value)
			{
				d_sourceview_hunk.wrap_mode = Gtk.WrapMode.WORD_CHAR;
			}
			else
			{
				d_sourceview_hunk.wrap_mode = Gtk.WrapMode.NONE;
			}
		}
	}

	public int tab_width
	{
		get { return (int)d_sourceview_hunk.tab_width; }
		set
		{
			if (value > 0)
			{
				d_sourceview_hunk.tab_width = (uint)value;
			}
		}
	}

	private bool d_has_selection;

	public bool has_selection
	{
		get { return d_has_selection; }
	}

	private DiffViewLinesRenderer d_old_lines;
	private DiffViewLinesRenderer d_new_lines;
	private DiffViewLinesRenderer d_sym_lines;

	construct
	{
		var gutter = d_sourceview_hunk.get_gutter(Gtk.TextWindowType.LEFT);

		d_old_lines = new DiffViewLinesRenderer(hunk, lines, DiffViewLinesRenderer.Style.OLD);
		d_new_lines = new DiffViewLinesRenderer(hunk, lines, DiffViewLinesRenderer.Style.NEW);
		d_sym_lines = new DiffViewLinesRenderer(hunk, lines, DiffViewLinesRenderer.Style.SYMBOL);

		this.bind_property("maxlines", d_old_lines, "maxlines", BindingFlags.DEFAULT | BindingFlags.SYNC_CREATE);
		this.bind_property("maxlines", d_new_lines, "maxlines", BindingFlags.DEFAULT | BindingFlags.SYNC_CREATE);

		d_old_lines.xpad = 8;
		d_new_lines.xpad = 8;
		d_sym_lines.xpad = 6;

		gutter.insert(d_old_lines, 0);
		gutter.insert(d_new_lines, 1);
		gutter.insert(d_sym_lines, 2);

		d_old_lines.notify["size"].connect(update_top_window_size);
		d_new_lines.notify["size"].connect(update_top_window_size);
		d_sym_lines.notify["size"].connect(update_top_window_size);

		if (handle_selection)
		{
			d_sourceview_hunk.button_press_event.connect(button_press_event_on_view);
			d_sourceview_hunk.motion_notify_event.connect(motion_notify_event_on_view);
			d_sourceview_hunk.button_release_event.connect(button_release_event_on_view);

			d_sourceview_hunk.get_style_context().add_class("handle-selection");

			d_sourceview_hunk.realize.connect(update_cursor);
			d_sourceview_hunk.notify["state-flags"].connect(update_cursor);
		}

		update_hunk_label();
		update_lines();

		d_sourceview_hunk.set_border_window_size(Gtk.TextWindowType.TOP, 1);
		d_sourceview_hunk.add_child_in_window(d_label_hunk, Gtk.TextWindowType.TOP, 0, 0);

		d_label_hunk.style_updated.connect(update_top_window_size);
		update_top_window_size();

		var settings = Gtk.Settings.get_default();
		settings.notify["gtk-application-prefer-dark-theme"].connect(update_theme);
		update_theme();
	}

	private void update_cursor()
	{
		var window = d_sourceview_hunk.get_window(Gtk.TextWindowType.TEXT);

		if (window == null)
		{
			return;
		}

 		var cursor = new Gdk.Cursor.for_display(d_sourceview_hunk.get_display(), Gdk.CursorType.LEFT_PTR);
		window.set_cursor(cursor);
	}

	private void update_theme()
	{
		var selection_attributes = new Gtk.SourceMarkAttributes();
		var added_attributes = new Gtk.SourceMarkAttributes();
		var removed_attributes = new Gtk.SourceMarkAttributes();

		var settings = Gtk.Settings.get_default();

		if (settings.gtk_application_prefer_dark_theme)
		{
			selection_attributes.background = Gdk.RGBA() { red = 52.0 / 255.0, green = 101.0 / 255.0, blue = 164.0 / 255.0, alpha = 1.0 };
			added_attributes.background = Gdk.RGBA() { red = 164.0 / 255.0, green = 0.0, blue = 0.0, alpha = 1.0 };
			removed_attributes.background = Gdk.RGBA() { red = 78.0 / 255.0, green = 154.0 / 255.0, blue = 6.0 / 255.0, alpha = 1.0 };
		}
		else
		{
			selection_attributes.background = Gdk.RGBA() { red = 168.0 / 255.0, green = 207.0 / 255.0, blue = 214.0 / 255.0, alpha = 1.0 };
			added_attributes.background = Gdk.RGBA() { red = 220.0 / 255.0, green = 1.0, blue = 220.0 / 255.0, alpha = 1.0 };
			removed_attributes.background = Gdk.RGBA() { red = 1.0, green = 220.0 / 255.0, blue = 220.0 / 255.0, alpha = 1.0 };
		}

		d_sourceview_hunk.set_mark_attributes(d_selection_category, selection_attributes, 0);
		d_sourceview_hunk.set_mark_attributes("added", added_attributes, 0);
		d_sourceview_hunk.set_mark_attributes("removed", removed_attributes, 0);
	}

	private bool get_line_selected(Gtk.TextIter iter)
	{
		var text_view = d_sourceview_hunk as Gtk.TextView;
		Gtk.TextIter start = iter;

		start.set_line_offset(0);
		var buffer = text_view.get_buffer() as Gtk.SourceBuffer;

		return buffer.get_source_marks_at_iter(start, d_selection_category) != null;
	}

	private bool get_line_is_diff(Gtk.TextIter iter)
	{
		var text_view = d_sourceview_hunk as Gtk.TextView;
		Gtk.TextIter start = iter;

		start.set_line_offset(0);
		var buffer = text_view.get_buffer() as Gtk.SourceBuffer;

		return (buffer.get_source_marks_at_iter(start, "added") != null) ||
		       (buffer.get_source_marks_at_iter(start, "removed") != null);
	}

	private bool get_iter_from_pointer_position(out Gtk.TextIter iter)
	{
		var text_view = d_sourceview_hunk as Gtk.TextView;
		var win = text_view.get_window(Gtk.TextWindowType.TEXT);
		int x, y, width, height;

		width = win.get_width();
		height = win.get_height();

		var pointer = Gdk.Display.get_default().get_device_manager().get_client_pointer();
		win.get_device_position(pointer, out x, out y, null);

		if (x < 0 || y < 0 || x > width || y > height)
		{
			return false;
		}

		int win_x, win_y;
		text_view.window_to_buffer_coords(Gtk.TextWindowType.TEXT, x, y, out win_x, out win_y);

		text_view.get_iter_at_location(out iter, win_x, win_y);

		return true;
	}

	private void select_range(Gtk.TextIter start, Gtk.TextIter end)
	{
		var text_view = d_sourceview_hunk as Gtk.TextView;
		var buffer = text_view.get_buffer() as Gtk.SourceBuffer;

		start.order(end);

		while (start.get_line() <= end.get_line())
		{
			start.set_line_offset(0);

			if (get_line_is_diff(start))
			{
				buffer.create_source_mark(null, d_selection_category, start);
			}

			if (!start.forward_line())
			{
				break;
			}
		}
	}

	private void deselect_range(Gtk.TextIter start, Gtk.TextIter end)
	{
		var text_view = d_sourceview_hunk as Gtk.TextView;
		var buffer = text_view.get_buffer() as Gtk.SourceBuffer;

		Gtk.TextIter real_start, real_end;

		real_start = start;
		real_start.set_line_offset(0);

		real_end = end;
		real_end.forward_to_line_end();

		buffer.remove_source_marks(real_start, real_end, d_selection_category);
	}

	private bool d_is_selecting;
	private bool d_is_deselecting;
	private Gtk.TextMark d_start_selection_mark;
	private Gtk.TextMark d_end_selection_mark;

	private bool button_press_event_on_view(Gdk.EventButton event)
	{
		if (event.button != 1)
		{
			return false;
		}

		Gtk.TextIter iter;
		if (!get_iter_from_pointer_position(out iter))
		{
			return false;
		}

		if (get_line_selected(iter))
		{
			d_is_deselecting = true;
			deselect_range(iter, iter);
		}
		else
		{
			d_is_selecting = true;
			select_range(iter, iter);
		}

		var text_view = d_sourceview_hunk as Gtk.TextView;
		var buffer = text_view.get_buffer();

		d_start_selection_mark = buffer.create_mark(null, iter, false);
		d_end_selection_mark = buffer.create_mark(null, iter, false);

		return false;
	}

	private bool motion_notify_event_on_view(Gdk.EventMotion event)
	{
		if (!d_is_selecting && !d_is_deselecting)
		{
			return false;
		}

		Gtk.TextIter iter;
		if (!get_iter_from_pointer_position(out iter))
		{
			return false;
		}

		var text_view = d_sourceview_hunk as Gtk.TextView;
		var buffer = text_view.get_buffer();

		Gtk.TextIter start, end, current;

		current = iter;

		buffer.get_iter_at_mark(out start, d_start_selection_mark);
		start.order(current);

		if (d_is_selecting)
		{
			select_range(start, current);
		}
		else
		{
			deselect_range(start, current);
		}

		buffer.get_iter_at_mark(out end, d_end_selection_mark);
		if (!end.in_range(start, current))
		{
			start = end;
			current = iter;

			start.order(current);

			if (d_is_selecting)
			{
				deselect_range(start, current);
			}
			else
			{
				select_range(start, current);
			}
		}

		buffer.move_mark(d_end_selection_mark, iter);

		return false;
	}

	private void update_has_selection()
	{
		var text_view = d_sourceview_hunk as Gtk.TextView;
		var buffer = text_view.get_buffer();

		Gtk.TextIter iter;
		buffer.get_start_iter(out iter);

		bool something_selected = false;

		if (get_line_selected(iter))
		{
			something_selected = true;
		}
		else
		{
			something_selected = (buffer as Gtk.SourceBuffer).forward_iter_to_source_mark(iter, d_selection_category);
		}

		if (something_selected != d_has_selection)
		{
			d_has_selection = something_selected;
			notify_property("has-selection");
		}
	}

	private bool button_release_event_on_view(Gdk.EventButton event)
	{
		if (event.button != 1)
		{
			return false;
		}

		d_is_selecting = false;
		d_is_deselecting = false;

		var text_view = d_sourceview_hunk as Gtk.TextView;
		var buffer = text_view.get_buffer();

		buffer.delete_mark(d_start_selection_mark);
		d_start_selection_mark = null;

		buffer.delete_mark(d_end_selection_mark);
		d_end_selection_mark = null;

		update_has_selection();

		return false;
	}

	private void update_top_window_size()
	{
		int minheight, natheight;
		d_label_hunk.get_preferred_height(out minheight, out natheight);

		if (natheight > 0)
		{
			d_sourceview_hunk.set_border_window_size(Gtk.TextWindowType.TOP, natheight);
		}

		var wx = d_new_lines.size +
		         d_new_lines.xpad * 2 +
		         d_old_lines.size +
		         d_old_lines.xpad * 2 +
		         d_sym_lines.size +
		         d_sym_lines.xpad * 2;

		d_sourceview_hunk.move_child(d_label_hunk, -wx + 6, 0);
	}

	protected override bool map_event(Gdk.EventAny event)
	{
		var ret = base.map_event(event);
		update_top_window_size();
		return ret;
	}

	private void update_hunk_label()
	{
		var h = hunk.get_header();
		var pos = h.last_index_of("@@");

		if (pos >= 0)
		{
			h = h.substring(pos + 2).chug();
		}

		h = h.chomp();
		d_label_hunk = new Gtk.Label(@"@@ -$(hunk.get_old_start()),$(hunk.get_old_lines()) +$(hunk.get_new_start()),$(hunk.get_new_lines()) @@ $h");
		d_label_hunk.halign = Gtk.Align.START;
		d_label_hunk.xalign = 0;
		d_label_hunk.selectable = false;
		d_label_hunk.can_focus = false;
		d_label_hunk.margin_top = 6;
		d_label_hunk.margin_bottom = 6;
		d_label_hunk.show();
	}

	private void update_lines()
	{
		var content = new StringBuilder();

		for (var i = 0; i < lines.size; i++)
		{
			var line = lines[i];
			var text = line.get_text();

			switch (line.get_origin())
			{
				case Ggit.DiffLineType.ADDITION:
					++d_added;
				break;
				case Ggit.DiffLineType.DELETION:
					++d_removed;
				break;
				case Ggit.DiffLineType.CONTEXT_EOFNL:
				case Ggit.DiffLineType.ADD_EOFNL:
				case Ggit.DiffLineType.DEL_EOFNL:
					text = text.substring(1);
				break;
			}

			if (i == lines.size - 1 && text.length > 0 && text[text.length - 1] == '\n')
			{
				text = text.slice(0, text.length - 1);
			}

			content.append(text);
		}

		var buffer = d_sourceview_hunk.buffer as Gtk.SourceBuffer;

		buffer.set_text((string)content.data);

		for (var i = 0; i < lines.size; i++)
		{
			var line = lines[i];
			string? category = null;

			switch (line.get_origin())
			{
				case Ggit.DiffLineType.ADDITION:
					category = "added";
				break;
				case Ggit.DiffLineType.DELETION:
					category = "removed";
				break;
			}

			if (category != null)
			{
				Gtk.TextIter iter;

				buffer.get_iter_at_line(out iter, i);
				buffer.create_source_mark(null, category, iter);
			}
		}

		notify_property("added");
		notify_property("removed");
	}
}

// ex:ts=4 noet