--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/python/ide/codeedit.py	Sun Nov 24 11:24:15 2013 +0100
@@ -0,0 +1,291 @@
+#!/usr/bin/python
+
+import sys
+import os
+from PyQt4.QtCore import *
+from PyQt4.QtGui import *
+import inspect
+
+GAP = 5
+
+def clipVal(v, mn, mx):
+   if v < mn: return mn
+   if v > mx: return mx
+   return v
+
+class InnerCode(QWidget):
+    textChanged = pyqtSignal()
+    def __init__(self, scrollArea):
+      super().__init__(scrollArea)
+      self.scrollArea = scrollArea
+      self.setFont(QFont('Courier', 12))
+      self.setFocusPolicy(Qt.StrongFocus)
+      # TODO: only beam cursor in text area..
+      self.setCursor(Qt.IBeamCursor)
+      h = QFontMetrics(self.font()).height()
+      self.errorPixmap = QPixmap('icons/error.png').scaled(h, h)
+      self.arrowPixmap = QPixmap('icons/arrow.png').scaled(h, h)
+      self.blinkcursor = False
+      self.errorlist = []
+      self.arrow = None
+      # Initial values:
+      self.setSource('')
+      self.CursorPosition = 0
+      self.t = QTimer(self)
+      self.t.timeout.connect(self.updateCursor)
+      self.t.setInterval(500)
+      self.t.start()
+
+    def updateCursor(self):
+        self.blinkcursor = not self.blinkcursor
+        self.update()
+        #self.update(self.cursorX, self.cursorY, self.charWidth, self.charHeight)
+
+    def setSource(self, src):
+        self.src = src
+        self.adjust()
+
+    def getSource(self):
+        return self.src
+
+    def setErrors(self, el):
+        self.errorlist = el
+        self.update()
+
+    def setCursorPosition(self, c):
+        self.cursorPosition = clipVal(c, 0, len(self.src))
+        self.update()
+
+    CursorPosition = property(lambda self: self.cursorPosition, setCursorPosition)
+
+    @property
+    def Rows(self):
+        # Make this nicer:
+        return self.src.split('\n')
+
+    @property
+    def CursorRow(self):
+        # TODO: make this nice.
+        txt = self.src[0:self.cursorPosition]
+        return len(txt.split('\n'))
+
+    @property
+    def CursorCol(self):
+        txt = self.src[0:self.cursorPosition]
+        curLine = txt.split('\n')[-1]
+        return len(curLine) + 1
+
+    @property
+    def CurrentLine(self):
+        return self.getRow(self.CursorRow)
+
+    def setRowCol(self, r, c):
+      prevRows = self.Rows[:r-1]
+      txt = '\n'.join(prevRows)
+      c = clipVal(c, 1, len(self.getRow(r)))
+      self.CursorPosition = len(txt) + c + 1
+      self.showRow(self.CursorRow)
+
+    def getRow(self, r):
+      rows = self.Rows
+      r = r - 1
+      if r < 0 or r > len(rows) - 1:
+         return ''
+      else:
+         return rows[r]
+
+    def showRow(self, r):
+      self.scrollArea.ensureVisible(self.xposTXT, r * self.charHeight, 4, self.charHeight)
+
+    # Annotations:
+    def addAnnotation(self, row, col, ln, msg):
+      pass
+
+    # Text modification:
+    def getChar(self, pos):
+      pass
+
+    def insertText(self, txt):
+        self.setSource(self.src[0:self.CursorPosition] + txt + self.src[self.CursorPosition:])
+        self.CursorPosition += len(txt)
+        self.textChanged.emit()
+
+    def deleteChar(self):
+        self.setSource(self.src[0:self.CursorPosition] + self.src[self.CursorPosition+1:])
+        self.textChanged.emit()
+
+    def GotoNextChar(self):
+        if self.src[self.CursorPosition] != '\n':
+            self.CursorPosition += 1
+
+    def GotoPrevChar(self):
+        if self.src[self.CursorPosition - 1] != '\n':
+            self.CursorPosition -= 1
+
+    def GotoNextLine(self):
+        curLine = self.CurrentLine
+        c = self.CursorCol - 1 # go to zero based
+        self.CursorPosition += len(curLine) - c + 1 # line break char!
+        curLine = self.CurrentLine
+        if len(curLine) < c:
+            self.CursorPosition += len(curLine)
+        else:
+            self.CursorPosition += c
+        self.showRow(self.CursorRow)
+
+    def GotoPrevLine(self):
+        c = self.CursorCol - 1 # go to zero based
+        self.CursorPosition -= c + 1 # line break char!
+        curLine = self.CurrentLine
+        if len(curLine) > c:
+            self.CursorPosition -= len(curLine) - c
+        self.showRow(self.CursorRow)
+
+    def paintEvent(self, event):
+      # Helper variables:
+      er = event.rect()
+      chw, chh = self.charWidth, self.charHeight
+      painter = QPainter(self)
+      # Background:
+      painter.fillRect(er, self.palette().color(QPalette.Base))
+      painter.fillRect(QRect(self.xposLNA, er.top(), 4 * chw, er.bottom() + 1), Qt.gray)
+      errorPen = QPen(Qt.red, 3)
+      # first and last row:
+      row1 = max(int(er.top() / chh) - 1, 1)
+      row2 = max(int(er.bottom() / chh) + 1, 1)
+      # Draw contents:
+      ypos = row1 * chh - self.charDescent
+      curRow = self.CursorRow
+      ydt = -chh + self.charDescent
+      for row in range(row1, row2 + 1):
+         if curRow == row and self.hasFocus():
+            painter.fillRect(self.xposTXT, ypos + ydt, er.width(), chh, Qt.yellow)
+            # cursor
+            if self.blinkcursor:
+               cursorX = self.CursorCol * self.charWidth + self.xposTXT - self.charWidth
+               cursorY = ypos + ydt
+               painter.fillRect(cursorX, cursorY, 2, chh, Qt.black)
+         painter.setPen(Qt.black)
+         painter.drawText(self.xposLNA, ypos, '{0}'.format(row))
+         xpos = self.xposTXT
+         painter.drawText(xpos, ypos, self.getRow(row))
+         if self.arrow and self.arrow.row == row:
+                painter.drawPixmap(self.xposERR, ypos + ydt, self.arrowPixmap)
+         curErrors = [e for e in self.errorlist if e.loc and e.loc.row == row]
+         for e in curErrors:
+               painter.drawPixmap(self.xposERR, ypos + ydt, self.errorPixmap)
+               painter.setPen(errorPen)
+               x = self.xposTXT + (e.loc.col - 1) * chw - 2
+               wt = e.loc.length * chw + 4
+               dy = self.charDescent
+               painter.drawLine(x, ypos + dy, x + wt, ypos + dy)
+               #painter.drawRoundedRect(x, ypos + ydt, wt, chh, 7, 7)
+               # print error balloon
+               #painter.drawText(x, ypos + chh, e.msg)
+         #if len(curErrors) > 0:
+         #   ypos += chh
+         ypos += chh
+
+    def keyPressEvent(self, event):
+      if event.matches(QKeySequence.MoveToNextChar):
+         self.GotoNextChar()
+      elif event.matches(QKeySequence.MoveToPreviousChar):
+         self.GotoPrevChar()
+      elif event.matches(QKeySequence.MoveToNextLine):
+         self.GotoNextLine()
+      elif event.matches(QKeySequence.MoveToPreviousLine):
+         self.GotoPrevLine()
+      elif event.matches(QKeySequence.MoveToNextPage):
+         for i in range(5):
+            self.GotoNextLine()
+      elif event.matches(QKeySequence.MoveToPreviousPage):
+         for i in range(5):
+            self.GotoPrevLine()
+      elif event.matches(QKeySequence.MoveToEndOfLine):
+         self.CursorPosition += len(self.CurrentLine) - self.CursorCol + 1
+      elif event.matches(QKeySequence.MoveToStartOfLine):
+         self.CursorPosition -= self.CursorCol - 1
+      elif event.matches(QKeySequence.Delete):
+         self.deleteChar()
+      elif event.matches(QKeySequence.InsertParagraphSeparator):
+         self.insertText('\n')
+      elif event.key() == Qt.Key_Backspace:
+         self.CursorPosition -= 1
+         self.deleteChar()
+      else:
+         char = event.text()
+         if char:
+            self.insertText(char)
+      self.update()
+
+    def mousePressEvent(self, event):
+        pos = event.pos()
+        if pos.x() > self.xposTXT and pos.x():
+            c = round((pos.x() - self.xposTXT) / self.charWidth)
+            r = int(pos.y() / self.charHeight) + 1
+            self.setRowCol(r, c)
+        super().mousePressEvent(event)
+
+    def adjust(self):
+        metrics = self.fontMetrics()
+        self.charHeight = metrics.height()
+        self.charWidth = metrics.width('x')
+        self.charDescent = metrics.descent()
+        self.xposERR = GAP
+        self.xposLNA = self.xposERR + GAP + self.errorPixmap.width()
+        self.xposTXT = self.xposLNA + 4 * self.charWidth + GAP
+        self.xposEnd = self.xposTXT + self.charWidth * 80
+        self.setMinimumWidth(self.xposEnd)
+        txt = self.src.split('\n')
+        self.setMinimumHeight(self.charHeight * len(txt))
+        self.update()
+
+class CodeEdit(QScrollArea):
+    def __init__(self):
+        super().__init__()
+        self.ic = InnerCode(self)
+        self.textChanged = self.ic.textChanged
+        self.setWidget(self.ic)
+        self.setWidgetResizable(True)
+        self.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOn)
+        self.setFocusPolicy(Qt.NoFocus)
+        self.showRow = self.ic.showRow
+        self.setRowCol = self.ic.setRowCol
+        self.FileName = None
+    Source = property(lambda s: s.ic.getSource(), lambda s, v: s.ic.setSource(v))
+
+    def setErrors(self, el):
+        self.ic.setErrors(el)
+
+    def setFocus(self):
+        self.ic.setFocus()
+        super().setFocus()
+
+    def setFileName(self, fn):
+        self.filename = fn
+        if fn:
+            fn = os.path.basename(fn)
+        else:
+            fn = 'Untitled'
+        self.setWindowTitle(fn)
+
+    def getFileName(self):
+        return self.filename
+    FileName = property(getFileName, setFileName)
+
+    def save(self):
+        if self.FileName:
+            s = self.Source
+            with open(self.FileName, 'w') as f:
+                f.write(s)
+
+
+if __name__ == '__main__':
+    app = QApplication(sys.argv)
+    ce = CodeEdit()
+    ce.show()
+    src = ''.join(inspect.getsourcelines(InnerCode)[0])
+    ce.Source = src
+    ce.resize(600, 800)
+    app.exec()
+