#!/usr/bin/env python

"""PyQt4 port of the xml/dombookmarks example from Qt v4.x"""

import sys
from PyQt4 import QtCore, QtGui, QtXml


class MainWindow(QtGui.QMainWindow):
    def __init__(self, parent=None):
        QtGui.QMainWindow.__init__(self, parent)
        
        self.xbelTree = XbelTree()
        self.setCentralWidget(self.xbelTree)
    
        self.createActions()
        self.createMenus()
    
        self.statusBar().showMessage(self.tr("Ready"))
    
        self.setWindowTitle(self.tr("DOM Bookmarks"))
        self.resize(480, 320)

    def open(self):
        fileName = QtGui.QFileDialog.getOpenFileName(self, self.tr("Open Bookmark File"),
                                                     QtCore.QDir.currentPath(),
                                                     self.tr("XBEL Files (*.xbel *.xml)"))
        if fileName.isEmpty():
            return
    
        inFile = QtCore.QFile(fileName)
        if not inFile.open(QtCore.QFile.ReadOnly | QtCore.QFile.Text):
            QtGui.QMessageBox.warning(self, self.tr("SAX Bookmarks"),
                                      self.tr("Cannot read file %1:\n%2.")
                                      .arg(fileName)
                                      .arg(inFile.errorString()))
            return

        if self.xbelTree.read(inFile):
            self.statusBar().showMessage(self.tr("File loaded"), 2000)

    def saveAs(self):
        fileName = QtGui.QFileDialog.getSaveFileName(self, self.tr("Save Bookmark File"),
                                                     QtCore.QDir.currentPath(),
                                                     self.tr("XBEL Files (*.xbel *.xml)"))
        if fileName.isEmpty():
            return
    
        outFile = QtCore.QFile(fileName)
        if not outFile.open(QtCore.QFile.WriteOnly | QtCore.QFile.Text):
            QtGui.QMessageBox.warning(self, self.tr("SAX Bookmarks"),
                                      self.tr("Cannot write file %1:\n%2.")
                                      .arg(fileName)
                                      .arg(outFile.errorString()))
            return

        if self.xbelTree.write(outFile):
            self.statusBar().showMessage(self.tr("File saved"), 2000)

    def about(self):
       QtGui.QMessageBox.about(self, self.tr("About DOM Bookmarks"), self.tr(
                               "The <b>DOM Bookmarks</b> example demonstrates how to "
                               "use Qt's DOM classes to read and write XML documents."))

    def createActions(self):
        self.openAct = QtGui.QAction(self.tr("&Open..."), self)
        self.openAct.setShortcut(self.tr("Ctrl+O"))
        self.connect(self.openAct, QtCore.SIGNAL("triggered()"), self.open)
    
        self.saveAsAct = QtGui.QAction(self.tr("&Save As..."), self)
        self.saveAsAct.setShortcut(self.tr("Ctrl+S"))
        self.connect(self.saveAsAct, QtCore.SIGNAL("triggered()"), self.saveAs)
    
        self.exitAct = QtGui.QAction(self.tr("E&xit"), self)
        self.exitAct.setShortcut(self.tr("Ctrl+Q"))
        self.connect(self.exitAct, QtCore.SIGNAL("triggered()"), self, QtCore.SLOT("close()"))
    
        self.aboutAct = QtGui.QAction(self.tr("&About"), self)
        self.connect(self.aboutAct, QtCore.SIGNAL("triggered()"), self.about)
    
        self.aboutQtAct = QtGui.QAction(self.tr("About &Qt"), self)
        self.connect(self.aboutQtAct, QtCore.SIGNAL("triggered()"), QtGui.qApp, QtCore.SLOT("aboutQt()"))

    def createMenus(self):
        self.fileMenu = self.menuBar().addMenu(self.tr("&File"))
        self.fileMenu.addAction(self.openAct)
        self.fileMenu.addAction(self.saveAsAct)
        self.fileMenu.addAction(self.exitAct)
    
        self.menuBar().addSeparator()
    
        self.helpMenu = self.menuBar().addMenu(self.tr("&Help"))
        self.helpMenu.addAction(self.aboutAct)
        self.helpMenu.addAction(self.aboutQtAct)


class XbelTree(QtGui.QTreeWidget):
    def __init__(self, parent=None):
        QtGui.QTreeWidget.__init__(self, parent)

        labels = QtCore.QStringList()
        labels << self.tr("Title") << self.tr("Location")
    
        self.header().setResizeMode(QtGui.QHeaderView.Stretch)
        self.setHeaderLabels(labels)
        
        self.domDocument = QtXml.QDomDocument()
        
        self.domElementForItem = {}
        
        self.folderIcon = QtGui.QIcon()
        self.bookmarkIcon = QtGui.QIcon()
    
        self.folderIcon.addPixmap(self.style().standardPixmap(QtGui.QStyle.SP_DirClosedIcon),
                                  QtGui.QIcon.Normal, QtGui.QIcon.Off)
        self.folderIcon.addPixmap(self.style().standardPixmap(QtGui.QStyle.SP_DirOpenIcon),
                                  QtGui.QIcon.Normal, QtGui.QIcon.On)
        self.bookmarkIcon.addPixmap(self.style().standardPixmap(QtGui.QStyle.SP_FileIcon))

    def read(self, device):     
        ok, errorStr, errorLine, errorColumn = self.domDocument.setContent(device, True)
        if not ok:
            QtGui.QMessageBox.information(self.window(), self.tr("DOM Bookmarks"),
                                          self.tr("Parse error at line %1, column %2:\n%3")
                                          .arg(errorLine).arg(errorColumn).arg(errorStr))
            return False

        root = self.domDocument.documentElement()
        if root.tagName() != "xbel":
            QtGui.QMessageBox.information(self.window(), self.tr("DOM Bookmarks"),
                                          self.tr("The file is not an XBEL file."))
            return False
        elif root.hasAttribute("version") and root.attribute("version") != "1.0":
            QtGui.QMessageBox.information(self.window(), self.tr("DOM Bookmarks"),
                                          self.tr("The file is not an XBEL version 1.0 file."))
            return False

        self.clear()

        self.disconnect(self, QtCore.SIGNAL("itemChanged(QTreeWidgetItem *, int)"),
                        self.updateDomElement)

        child = root.firstChildElement("folder")
        while not child.isNull():
            self.parseFolderElement(child)
            child = child.nextSiblingElement("folder")

        self.connect(self, QtCore.SIGNAL("itemChanged(QTreeWidgetItem *, int)"),
                     self.updateDomElement)
    
        return True

    def write(self, device):
        indentSize = 4
        
        out = QtCore.QTextStream(device)
        self.domDocument.save(out, indentSize)
        return True

    def updateDomElement(self, item, column):
        element = self.domElementForItem.get(item)
        if not element.isNull():
            if column == 0:
                oldTitleElement = element.firstChildElement("title")
                newTitleElement = self.domDocument.createElement("title")
    
                newTitleText = self.domDocument.createTextNode(item.text(0))
                newTitleElement.appendChild(newTitleText)
    
                element.replaceChild(newTitleElement, oldTitleElement)
            else:
                if element.tagName() == "bookmark":
                    element.setAttribute("href", item.text(1))

    def parseFolderElement(self, element, parentItem=None):
        item = self.createItem(element, parentItem)
    
        title = element.firstChildElement("title").text()
        if title.isEmpty():
            title = QtCore.QObject.tr("Folder")
    
        item.setFlags(item.flags() | QtCore.Qt.ItemIsEditable)
        item.setIcon(0, self.folderIcon)
        item.setText(0, title)
    
        folded = (element.attribute("folded") != "no")
        self.setItemExpanded(item, not folded)
    
        child = element.firstChildElement()
        while not child.isNull():
            if child.tagName() == "folder":
                self.parseFolderElement(child, item)
            elif child.tagName() == "bookmark":
                childItem = self.createItem(child, item)
    
                title = child.firstChildElement("title").text()
                if title.isEmpty():
                    title = QtCore.QObject.tr("Folder")
    
                childItem.setFlags(item.flags() | QtCore.Qt.ItemIsEditable)
                childItem.setIcon(0, self.bookmarkIcon)
                childItem.setText(0, title)
                childItem.setText(1, child.attribute("href"))
            elif child.tagName() == "separator":
                childItem = self.createItem(child, item)
                childItem.setFlags(item.flags() & ~(QtCore.Qt.ItemIsSelectable | QtCore.Qt.ItemIsEditable))
                childItem.setText(0, QtCore.QString(30 * "\xB7"))
    
            child = child.nextSiblingElement()

    def createItem(self, element, parentItem=None):
        item = QtGui.QTreeWidgetItem()
        
        if parentItem is not None:
            item = QtGui.QTreeWidgetItem(parentItem)
        else:
            item = QtGui.QTreeWidgetItem(self)
    
        self.domElementForItem[item] = element
        return item


if __name__ == '__main__':
    app = QtGui.QApplication(sys.argv)
    mainWin = MainWindow()
    mainWin.show()
    sys.exit(app.exec_())