jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2020, Itamar S. <itamar8910@gmail.com>
3 * Copyright (c) 2022, the SerenityOS developers.
4 *
5 * SPDX-License-Identifier: BSD-2-Clause
6 */
7
8#include "DiffViewer.h"
9#include <AK/Debug.h>
10#include <LibDiff/Hunks.h>
11#include <LibGUI/AbstractView.h>
12#include <LibGUI/Painter.h>
13#include <LibGUI/Scrollbar.h>
14#include <LibGfx/Color.h>
15#include <LibGfx/Font/FontDatabase.h>
16#include <LibGfx/Palette.h>
17
18namespace HackStudio {
19
20void DiffViewer::paint_event(GUI::PaintEvent& event)
21{
22 GUI::Painter painter(*this);
23 painter.add_clip_rect(widget_inner_rect());
24 painter.add_clip_rect(event.rect());
25 painter.fill_rect(event.rect(), palette().color(background_role()));
26 painter.translate(frame_thickness(), frame_thickness());
27 painter.translate(-horizontal_scrollbar().value(), -vertical_scrollbar().value());
28
29 // Why we need to translate here again? We've already translated the painter.
30 // Anyways, it paints correctly so I'll leave it like this.
31 painter.fill_rect_with_dither_pattern(
32 separator_rect().translated(horizontal_scrollbar().value(), vertical_scrollbar().value()),
33 Gfx::Color::LightGray,
34 Gfx::Color::White);
35
36 size_t y_offset = 10;
37 size_t current_original_line_index = 0;
38 for (auto const& hunk : m_hunks) {
39 for (size_t i = current_original_line_index; i < hunk.original_start_line; ++i) {
40 draw_line(painter, m_original_lines[i], y_offset, LinePosition::Both, LineType::Normal);
41 y_offset += line_height();
42 }
43 current_original_line_index = hunk.original_start_line + hunk.removed_lines.size();
44
45 size_t left_y_offset = y_offset;
46 for (auto const& removed_line : hunk.removed_lines) {
47 draw_line(painter, removed_line, left_y_offset, LinePosition::Left, LineType::Diff);
48 left_y_offset += line_height();
49 }
50 for (int i = 0; i < (int)hunk.added_lines.size() - (int)hunk.removed_lines.size(); ++i) {
51 draw_line(painter, "", left_y_offset, LinePosition::Left, LineType::Missing);
52 left_y_offset += line_height();
53 }
54
55 size_t right_y_offset = y_offset;
56 for (auto const& added_line : hunk.added_lines) {
57 draw_line(painter, added_line, right_y_offset, LinePosition::Right, LineType::Diff);
58 right_y_offset += line_height();
59 }
60 for (int i = 0; i < (int)hunk.removed_lines.size() - (int)hunk.added_lines.size(); ++i) {
61 draw_line(painter, "", right_y_offset, LinePosition::Right, LineType::Missing);
62 right_y_offset += line_height();
63 }
64
65 VERIFY(left_y_offset == right_y_offset);
66 y_offset = left_y_offset;
67 }
68 for (size_t i = current_original_line_index; i < m_original_lines.size(); ++i) {
69 draw_line(painter, m_original_lines[i], y_offset, LinePosition::Both, LineType::Normal);
70 y_offset += line_height();
71 }
72}
73
74void DiffViewer::draw_line(GUI::Painter& painter, DeprecatedString const& line, size_t y_offset, LinePosition line_position, LineType line_type)
75{
76 size_t line_width = font().width(line);
77
78 constexpr size_t padding = 10;
79 size_t left_side_x_offset = padding;
80 size_t right_side_x_offset = separator_rect().x() + padding;
81
82 // FIXME: Long lines will overflow out of their side of the diff view
83 Gfx::IntRect left_line_rect { (int)left_side_x_offset, (int)y_offset, (int)line_width, (int)line_height() };
84 Gfx::IntRect right_line_rect { (int)right_side_x_offset, (int)y_offset, (int)line_width, (int)line_height() };
85 auto color = palette().color(foreground_role());
86
87 if (line_position == LinePosition::Left || line_position == LinePosition::Both) {
88 painter.draw_text(left_line_rect, line, Gfx::TextAlignment::TopLeft, color);
89 if (line_type != LineType::Normal) {
90 Gfx::IntRect outline = { (int)left_side_x_offset, ((int)y_offset) - 2, separator_rect().x() - (int)(padding * 2), (int)line_height() };
91 if (line_type == LineType::Diff) {
92 painter.fill_rect(
93 outline,
94 red_background());
95 }
96 if (line_type == LineType::Missing) {
97 painter.fill_rect(
98 outline,
99 gray_background());
100 }
101 }
102 }
103 if (line_position == LinePosition::Right || line_position == LinePosition::Both) {
104 painter.draw_text(right_line_rect, line, Gfx::TextAlignment::TopLeft, color);
105 if (line_type != LineType::Normal) {
106 Gfx::IntRect outline = { (int)right_side_x_offset, ((int)y_offset) - 2, frame_inner_rect().width() - separator_rect().x() - (int)(padding * 2) - 10, (int)line_height() };
107 if (line_type == LineType::Diff) {
108 painter.fill_rect(
109 outline,
110 green_background());
111 }
112 if (line_type == LineType::Missing) {
113 painter.fill_rect(
114 outline,
115 gray_background());
116 }
117 }
118 }
119}
120
121size_t DiffViewer::line_height() const
122{
123 return font().pixel_size_rounded_up() + 4;
124}
125
126Gfx::IntRect DiffViewer::separator_rect() const
127{
128 return Gfx::IntRect { frame_inner_rect().width() / 2 - 2,
129 0,
130 4,
131 frame_inner_rect().height() };
132}
133
134void DiffViewer::set_content(DeprecatedString const& original, DeprecatedString const& diff)
135{
136 m_original_lines = split_to_lines(original);
137 m_hunks = Diff::parse_hunks(diff);
138
139 if constexpr (DIFF_DEBUG) {
140 for (size_t i = 0; i < m_original_lines.size(); ++i)
141 dbgln("{}:{}", i, m_original_lines[i]);
142 }
143}
144
145DiffViewer::DiffViewer()
146{
147 setup_properties();
148}
149
150DiffViewer::DiffViewer(DeprecatedString const& original, DeprecatedString const& diff)
151 : m_original_lines(split_to_lines(original))
152 , m_hunks(Diff::parse_hunks(diff))
153{
154 setup_properties();
155}
156
157void DiffViewer::setup_properties()
158{
159 set_font(Gfx::FontDatabase::default_fixed_width_font());
160 set_background_role(ColorRole::Base);
161 set_foreground_role(ColorRole::BaseText);
162}
163
164Vector<DeprecatedString> DiffViewer::split_to_lines(DeprecatedString const& text)
165{
166 // NOTE: This is slightly different than text.split('\n')
167 Vector<DeprecatedString> lines;
168 size_t next_line_start_index = 0;
169 for (size_t i = 0; i < text.length(); ++i) {
170 if (text[i] == '\n') {
171 auto line_text = text.substring(next_line_start_index, i - next_line_start_index);
172 lines.append(move(line_text));
173 next_line_start_index = i + 1;
174 }
175 }
176 lines.append(text.substring(next_line_start_index, text.length() - next_line_start_index));
177 return lines;
178}
179
180Gfx::Color DiffViewer::red_background()
181{
182 static Gfx::Color color = Gfx::Color::from_argb(0x88ff0000);
183 return color;
184}
185
186Gfx::Color DiffViewer::green_background()
187{
188 static Gfx::Color color = Gfx::Color::from_argb(0x8800ff00);
189 return color;
190}
191
192Gfx::Color DiffViewer::gray_background()
193{
194 static Gfx::Color color = Gfx::Color::from_argb(0x88888888);
195 return color;
196}
197
198void DiffViewer::update_content_size()
199{
200 if (m_hunks.is_empty()) {
201 set_content_size({ 0, 0 });
202 return;
203 }
204
205 size_t num_lines = 0;
206 size_t current_original_line_index = 0;
207 for (auto const& hunk : m_hunks) {
208 num_lines += ((int)hunk.original_start_line - (int)current_original_line_index);
209
210 num_lines += hunk.removed_lines.size();
211 if (hunk.added_lines.size() > hunk.removed_lines.size()) {
212 num_lines += ((int)hunk.added_lines.size() - (int)hunk.removed_lines.size());
213 }
214 current_original_line_index = hunk.original_start_line + hunk.removed_lines.size();
215 }
216 num_lines += ((int)m_original_lines.size() - (int)current_original_line_index);
217
218 // TODO: Support Horizontal scrolling
219 set_content_size({ 0, (int)(num_lines * line_height()) });
220}
221
222void DiffViewer::resize_event(GUI::ResizeEvent& event)
223{
224 AbstractScrollableWidget::resize_event(event);
225 update_content_size();
226}
227
228}