Add Text tool

closes #11
Add an initial version of the text tool.
This commit adds:
- Basic text tool.
- On demand thickness and color update.
- Generalized logic for future widget based tools.

src/tools/text/texttool.cpp

@@ -0,0 +1,151 @@
+// Copyright(c) 2017-2018 Alejandro Sirgo Rica & Contributors
+//
+// This file is part of Flameshot.
+//
+//     Flameshot 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 3 of the License, or
+//     (at your option) any later version.
+//
+//     Flameshot 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 Flameshot.  If not, see <http://www.gnu.org/licenses/>.
+
+#include "texttool.h"
+#include "textwidget.h"
+#include "textconfig.h"
+
+#define BASE_POINT_SIZE 8
+
+TextTool::TextTool(QObject *parent) : CaptureTool(parent) {
+
+}
+
+bool TextTool::isValid() const {
+    return !m_text.isEmpty();
+}
+
+bool TextTool::closeOnButtonPressed() const {
+    return false;
+}
+
+bool TextTool::isSelectable() const {
+    return true;
+}
+
+bool TextTool::showMousePreview() const {
+    return false;
+}
+
+QIcon TextTool::icon(const QColor &background, bool inEditor) const {
+    Q_UNUSED(inEditor);
+    return QIcon(iconPath(background) + "text.png");
+}
+
+QString TextTool::name() const {
+    return tr("Text");
+}
+
+QString TextTool::nameID() {
+    return "";
+}
+
+QString TextTool::description() const {
+    return tr("Add text to your capture");
+}
+
+QWidget *TextTool::widget() {
+    TextWidget *w = new TextWidget();
+    w->setTextColor(m_color);
+    m_font.setPointSize(m_size + BASE_POINT_SIZE);
+    w->setFont(m_font);
+    connect(w, &TextWidget::textUpdated,
+            this, &TextTool::updateText);
+    m_widget = w;
+      return w;
+}
+
+QWidget *TextTool::configurationWidget() {
+    TextConfig *w = nullptr;//new TextConfig();
+    // TODO CONNECT
+    return w;
+}
+
+CaptureTool *TextTool::copy(QObject *parent) {
+    return new TextTool(parent);
+}
+
+void TextTool::undo(QPixmap &pixmap) {
+    QPainter p(&pixmap);
+    p.drawPixmap(m_backupArea.topLeft(), m_pixmapBackup);
+}
+
+void TextTool::process(QPainter &painter, const QPixmap &pixmap, bool recordUndo) {
+    // TODO updateBackup() of others
+    if (m_text.isEmpty()) {
+        return;
+    }
+    QFontMetrics fm(m_font);
+    QSize size(fm.boundingRect(QRect(), 0, m_text).size());
+    m_backupArea.setSize(size);
+    if (recordUndo) {
+        m_pixmapBackup = pixmap.copy(m_backupArea + QMargins(0, 0, 5, 5));
+    }
+    // draw text
+    painter.setFont(m_font);
+    painter.setPen(m_color);
+    painter.drawText(m_backupArea + QMargins(-5, -5, 5, 5), m_text);
+}
+
+void TextTool::paintMousePreview(QPainter &painter, const CaptureContext &context) {
+    Q_UNUSED(painter);
+    Q_UNUSED(context);
+}
+
+void TextTool::drawEnd(const QPoint &p) {
+    m_backupArea.moveTo(p);
+}
+
+void TextTool::drawMove(const QPoint &p) {
+    m_widget->move(p);
+}
+
+void TextTool::drawStart(const CaptureContext &context) {
+    m_color = context.color;
+    m_size = context.thickness;
+    emit requestAction(REQ_ADD_CHILD_WIDGET);
+}
+
+void TextTool::pressed(const CaptureContext &context) {
+    Q_UNUSED(context);
+}
+
+void TextTool::colorChanged(const QColor &c) {
+    m_color = c;
+    if (m_widget) {
+        m_widget->setTextColor(c);
+    }
+}
+
+void TextTool::thicknessChanged(const int th) {
+    m_size = th;
+    m_font.setPointSize(m_size + BASE_POINT_SIZE);
+    if (m_widget) {
+        m_widget->setFont(m_font);
+    }
+}
+
+void TextTool::updateText(const QString &s) {
+    m_text = s;
+}
+
+void TextTool::setFont(const QFont &f) {
+    m_font = f;
+    if (m_widget) {
+        m_widget->setFont(f);
+    }
+}