[components] Add a basic component for a Python script editor

meshroom/ui/components/scriptEditor.py

@@ -0,0 +1,60 @@
+from PySide2.QtCore import QObject, Slot
+
+from io import StringIO
+from contextlib import redirect_stdout
+
+class ScriptEditorManager(QObject):
+
+    def __init__(self, parent=None):
+        super(ScriptEditorManager, self).__init__(parent=parent)
+        self._history = []
+        self._index = -1
+
+        self._globals = {}
+        self._locals = {}
+
+
+    @Slot(str, result=str)
+    def process(self, script):
+        """ Execute the provided input script, capture the output from the standard output, and return it. """
+        stdout = StringIO()
+        with redirect_stdout(stdout):
+            try:
+                exec(script, self._globals, self._locals)
+            except Exception as exception:
+                # Format and print the exception to stdout, which will be captured
+                print("{}: {}".format(type(exception).__name__, exception))
+
+        result = stdout.getvalue().strip()
+
+        # Add the script to the history and move up the index
+        self._history.append(script)
+        self._index = self._index + 1
+
+        return result
+
+    @Slot()
+    def clearHistory(self):
+        """ Clear the list of executed scripts and reset the index. """
+        self._history = []
+        self._index = -1
+
+    @Slot(result=str)
+    def getNextScript(self):
+        """ Get the next entry in the history of executed scripts and update the index adequately.
+            If there is no next entry, return an empty string. """
+        if self._index + 1 < len(self._history) and len(self._history) > 0:
+            self._index = self._index + 1
+            return self._history[self._index]
+        return ""
+
+    @Slot(result=str)
+    def getPreviousScript(self):
+        """ Get the previous entry in the history of executed scripts and update the index adequately.
+            If there is no previous entry, return an empty string. """
+        if self._index - 1 >= 0 and self._index - 1 < len(self._history):
+            self._index = self._index - 1
+            return self._history[self._index]
+        elif self._index == 0 and len(self._history):
+            return self._history[self._index]
+        return ""