Show link on hover (#634)

ReText/editor.py

@@ -52,6 +52,9 @@
 	'restDirectives':       {'light': '#800080', 'dark': '#d070d0'},
 	'restRoles':            {'light': '#800000', 'dark': '#d07070'},
 	'whitespaceOnEnd':      {'light': '#80e1e1a5', 'dark': '#8096966e'},
+	# Preview
+	'urlPopupArea':         {'light': '#fafafafa', 'dark': '#fa323232'},
+	'urlPopupBorder':       {'light': '#64323232', 'dark': '#64fafafa'},
 }
 
 colorValues = {}

ReText/webenginepreview.py

@@ -17,9 +17,11 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 from ReText import globalSettings
+from ReText.editor import getColor
 from ReText.syncscroll import SyncScroll
 from PyQt6.QtCore import QEvent, Qt
-from PyQt6.QtGui import QDesktopServices, QFontInfo, QGuiApplication, QTextDocument
+from PyQt6.QtGui import QDesktopServices, QFontInfo, QGuiApplication, QTextDocument, QColor
+from PyQt6.QtWidgets import QLabel
 from PyQt6.QtWebEngineCore import (
     QWebEnginePage,
     QWebEngineSettings,
@@ -37,12 +39,53 @@ def interceptRequest(self, info):
             info.block(True)
 
 
+def str_rgba(color: QColor):
+    """ Todo: More elegant use of QColor with alpha in stylesheet """
+    return "rgba({r}, {g}, {b}, {a})".format(
+        r = color.red(),
+        g = color.green(),
+        b = color.blue(),
+        a = color.alpha())
+
+class UrlPopup(QLabel):
+    def __init__(self, window):
+        super().__init__(window)
+        self.window = window
+
+        self.setStyleSheet('''
+            border: 1px solid {:s};
+            border-radius: 3px;
+            background: {:s};
+            '''.format(str_rgba(getColor('urlPopupBorder')),
+                       str_rgba(getColor('urlPopupArea'))))
+        self.fontHeight = self.fontMetrics().height()
+        self.setVisible(False)
+
+    def pop(self, url: str):
+        """ Show link target on mouse hover
+
+        QWebEnginePage emits signal 'linkHovered' which provides
+        url: str -- target of link hovered (or empty on mouse-release)
+        """
+        if url:
+            self.setText(url)
+            windowBottom = self.window.rect().bottom()
+            textWidth = self.fontMetrics().horizontalAdvance(url)
+            self.setGeometry(-2, windowBottom-self.fontHeight-6,
+                    textWidth+10, self.fontHeight+10)
+            self.setVisible(True)
+        else:
+            self.setVisible(False)
+
+
 class ReTextWebEnginePage(QWebEnginePage):
     def __init__(self, parent, tab):
         QWebEnginePage.__init__(self, parent)
         self.tab = tab
         self.interceptor = ReTextWebEngineUrlRequestInterceptor(self)
         self.setUrlRequestInterceptor(self.interceptor)
+        self.urlPopup = UrlPopup(self.tab.p)
+        self.linkHovered.connect(self.urlPopup.pop)
 
     def setScrollPosition(self, pos):
         self.runJavaScript("window.scrollTo(%s, %s);" % (pos.x(), pos.y()))