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# Copyright 2004-2008 Nanorex, Inc.  See LICENSE file for details.
"""
Ui_PartWindow.py provides the part window class.

@version: $Id$
@copyright: 2004-2008 Nanorex, Inc.  See LICENSE file for details.

To Do:
- Reorder widget and layout creation so that the code is easier to follow
and understand. Also will make it more obvious were to insert future widgets
and layouts post Rattlesnake.
- Add "Right Area" frame (pwRightArea) containing the glpane.
- More attr renaming.
- Review/refine layouts one last time.
- Remove any unused methods I missed.
- Fix window title(s) when MDI is enabled (after Rattlesnake release)

History:

Mark 2007-06-27: PartWindow and GridPosition classes moved here from MWSemantics.py.
Mark 2008-01-05: Implemented the new U{B{NE1 Part Window Framework (SDI)}
<http://www.nanoengineer-1.net/mediawiki/index.php?title=NE1_Main_Window_Framework>}
which includes moving the history widget to the new reportDockWidget, renaming
key attrs and widgets (i.e. pwLeftArea and pwBottomArea)
"""

import os

from PyQt4.Qt import Qt, QWidget, QFrame, QVBoxLayout, QSplitter, QTimer
from PyQt4.Qt import QTabWidget, QScrollArea, QSizePolicy, SIGNAL
from graphics.widgets.GLPane import GLPane
from PM.PM_Constants import PM_DEFAULT_WIDTH, PM_MAXIMUM_WIDTH, PM_MINIMUM_WIDTH
from utilities.icon_utilities import geticon
from modelTree.ModelTree import ModelTree
from utilities.qt4transition import qt4warnDestruction
from utilities import debug_flags
import foundation.env as env
from utilities.debug import print_compact_traceback

from utilities.prefs_constants import captionFullPath_prefs_key
from ne1_ui.SelectNodeByNameDockWidget import SelectNodeByNameDockWidget

_DEBUG = False # Do not commit with True

class _pwProjectTabWidget(QTabWidget):
    """
    A helper class for the Project Tab Widget (a QTabWidget).
    It was created to help fix bug 2522.

    @note: [bruce 070829] to fix bug 2522 I need to intercept removeTab(),
    so I made this subclass. It needs to know the GLPane, which is set using
    KLUGE_setGLPane().

    @see: U{B{Bug 2522}
    <https://mirror2.cvsdude.com/bugz/polosims_svn/show_bug.cgi?id=2540>}
    """
    #bruce 070829 made this subclass re bug 2522
    def KLUGE_setGLPane(self, glpane):
        self._glpane = glpane
        return
    def removeTab(self, index):
        res = QTabWidget.removeTab(self, index)
            # note: AFAIK, res is always None
        if index != -1: # -1 happens!
            glpane = self._glpane
            glpane.gl_update_confcorner() # fix bug 2522 (try 2)
        return res
    pass

class LeftFrame(QFrame):
    """
    The left area frame that contains the model tree and property manager.

    This subclass of QFrame was written exclusively to deal with the undersired
    behavior of the spitter moving while resizing the part window.
    """
    def __init__(self, parent):
        QFrame.__init__(self, parent)
        self.parent = parent
        return

    def resizeEvent(self, event):
        """
        Reimplementation of the resizeEvent handler. It determines if the
        frame is being resized by the splitter (allowed) or programmably
        via a resize of the part window (not allowed).
        """
        if self.parent.resizeTimer.isActive():
            # LeftFrame is being resized (programmably) by the part window
            # as the user drags the resize handle.
            # We don't want that, so don't change the splitter position.
            return

        # LeftFrame is most likely being resized by the user via the splitter,
        # but it is also possible that the user clicked the maximize/restore
        # button. If the user did this, set the splitter position to the
        # "old" width (not the current width) since it has been changed
        # programmably (and we didn't want that).
        size = event.size()
        oldSize = event.oldSize()
        delta = abs(size.width() - oldSize.width())
        if delta < 10: # 10 pixels. Value chosen based on experimentation.
            self.parent.splitterPosition = size.width()
            if _DEBUG:
                print "New Size: ", self.parent.splitterPosition
        else:
            self.parent.splitterPosition = oldSize.width()
            if _DEBUG:
                print "Old Size: ", self.parent.splitterPosition
        QWidget.resizeEvent(self, event)
        return

class Ui_PartWindow(QWidget):
    """
    The Ui_PartWindow class provides a Part Window UI object composed of three
    primary areas:

    - The "left area" contains the Project TabWidget which contains
    the Model Tree and Property Manager (tabs). Other tabs (widgets)
    can be added as needed.

    - The "right area" contains the Graphics Area (i.e. glpane) displaying
    the current model.

    - The "bottom area" lives below the left and right areas, spanning
    the full width of the part window. It can be used whenever a landscape
    layout is needed (i.e. the Sequence Editor). Typically, this area is
    not used and is hidden by default.

    A "part window" splitter lives between the left and right areas that
    allow the user to resize the shared area occupied by them. There is no
    splitter between the top and bottom areas.

    This class supports and is limited to a B{Single Document Interface (SDI)}.
    In time, NE1 will migrate to and support a Multiple Document Interface (MDI)
    to allow multiple project documents (i.e. parts, assemblies,
    simulations, text files, graphs, tables, etc. documents) to be available
    within the common workspace of the NE1 main window.

    @see: U{B{NE1 Main Window Framework}
    <http://www.nanoengineer-1.net/mediawiki/index.php?title=NE1_Main_Window_Framework>}
    """
    widgets = [] # For debugging purposes.
    splitterPosition = PM_DEFAULT_WIDTH
    _previous_splitterPosition = PM_DEFAULT_WIDTH
        # Used for restoring the splitter position when collapsing/expanding
        # the left area.

    def __init__(self, assy, parent):
        """
        Constructor for the part window.

        @param assy: The assembly (part)
        @type  assy: Assembly

        @param parent: The parent widget.
        @type  parent: U{B{QMainWindow}
                       <http://doc.trolltech.com/4/qmainwindow.html>}
        """
        QWidget.__init__(self, parent)
        self.parent = parent
        self.assy = assy
            # note: to support MDI, self.assy would probably need to be a
            # different assembly for each PartWindow.
            # [bruce 080216 comment]
        self.setWindowIcon(geticon("ui/border/Part.png"))
        self.updateWindowTitle()

        # The main layout for the part window is a VBoxLayout <pwVBoxLayout>.
        self.pwVBoxLayout = QVBoxLayout(self)
        pwVBoxLayout = self.pwVBoxLayout
        pwVBoxLayout.setMargin(0)
        pwVBoxLayout.setSpacing(0)

        # ################################################################
        # <pwSplitter> is the horizontal splitter b/w the
        # pwLeftArea (mt and pm) and the glpane.
        self.pwSplitter = QSplitter(Qt.Horizontal)
        pwSplitter = self.pwSplitter
        pwSplitter.setObjectName("pwSplitter")
        pwSplitter.setHandleWidth(3) # 3 pixels wide.
        pwVBoxLayout.addWidget(pwSplitter)

        # ##################################################################
        # <pwLeftArea> is the container holding the pwProjectTabWidget.
        # Note: Making pwLeftArea (and pwRightArea and pwBottomArea) QFrame
        # widgets has the benefit of making it easy to draw a border around
        # each area. One purpose of this would be to help developers understand
        # (visually) how the part window is laid out. I intend to add a debug
        # pref to draw part window area borders and add "What's This" text to
        # them. Mark 2008-01-05.
        self.pwLeftArea = LeftFrame(self)
        pwLeftArea = self.pwLeftArea
        pwLeftArea.setObjectName("pwLeftArea")
        pwLeftArea.setMinimumWidth(PM_MINIMUM_WIDTH)
        pwLeftArea.setMaximumWidth(PM_MAXIMUM_WIDTH)

        # Setting the frame style like this is nice since it clearly
        # defines the splitter at the top-left corner.
        pwLeftArea.setFrameStyle( QFrame.Panel | QFrame.Sunken )

        # This layout will contain splitter (above) and the pwBottomArea.
        leftChannelVBoxLayout = QVBoxLayout(pwLeftArea)
        leftChannelVBoxLayout.setMargin(0)
        leftChannelVBoxLayout.setSpacing(0)

        pwSplitter.addWidget(pwLeftArea)

        # Makes it so pwLeftArea is not collapsible.
        pwSplitter.setCollapsible (0, False)

        # ##################################################################
        # <pwProjectTabWidget> is a QTabWidget that contains the MT and PM
        # widgets. It lives in the "left area" of the part window.
        self.pwProjectTabWidget = _pwProjectTabWidget()
           # _pwProjectTabWidget subclasses QTabWidget
           # Note [bruce 070829]: to fix bug 2522 I need to intercept
           # self.pwProjectTabWidget.removeTab, so I made it a subclass of
           # QTabWidget. It needs to know the GLPane, but that's not created
           # yet, so we set it later using KLUGE_setGLPane (below).
           # Note: No parent supplied. Could this be the source of the
           # minor vsplitter resizing problem I was trying to resolve a few
           # months ago?  Try supplying a parent later. Mark 2008-01-01
        self.pwProjectTabWidget.setObjectName("pwProjectTabWidget")
        self.pwProjectTabWidget.setCurrentIndex(0)
        self.pwProjectTabWidget.setAutoFillBackground(True)

        # Create the model tree "tab" widget. It will contain the MT GUI widget.
        # Set the tab icon, too.
        self.modelTreeTab = QWidget()
        self.modelTreeTab.setObjectName("modelTreeTab")
        self.pwProjectTabWidget.addTab(
            self.modelTreeTab,
            geticon("ui/modeltree/Model_Tree.png"),
            "")

        modelTreeTabLayout = QVBoxLayout(self.modelTreeTab)
        modelTreeTabLayout.setMargin(0)
        modelTreeTabLayout.setSpacing(0)

        # Create the model tree (GUI) and add it to the tab layout.
        self.modelTree = ModelTree(self.modelTreeTab, parent)
        self.modelTree.modelTreeGui.setObjectName("modelTreeGui")
        modelTreeTabLayout.addWidget(self.modelTree.modelTreeGui)

        # Create the property manager "tab" widget. It will contain the PropMgr
        # scroll area, which will contain the property manager and all its
        # widgets.
        self.propertyManagerTab = QWidget()
        self.propertyManagerTab.setObjectName("propertyManagerTab")

        self.propertyManagerScrollArea = QScrollArea(self.pwProjectTabWidget)
        self.propertyManagerScrollArea.setObjectName("propertyManagerScrollArea")
        self.propertyManagerScrollArea.setWidget(self.propertyManagerTab)
        self.propertyManagerScrollArea.setWidgetResizable(True)
        # Eureka!
        # setWidgetResizable(True) will resize the Property Manager (and its
        # contents) correctly when the scrollbar appears/disappears.
        # It even accounts correctly for collapsed/expanded groupboxes!
        # Mark 2007-05-29

        # Add the property manager scroll area as a "tabbed" widget.
        # Set the tab icon, too.
        self.pwProjectTabWidget.addTab(
            self.propertyManagerScrollArea,
            geticon("ui/modeltree/Property_Manager.png"),
            "")

        # Finally, add the "pwProjectTabWidget" to the left channel layout.

        leftChannelVBoxLayout.addWidget(self.pwProjectTabWidget)


        # Create the glpane and make it a child of the part splitter.
        self.glpane = GLPane(assy, self, 'glpane name', parent)
            # note: our owner (MWsemantics) assumes
            # there is just this one GLPane for assy, and stores it
            # into assy as assy.o and assy.glpane. [bruce 080216 comment]

        # Add what's this text to self.glpane.
        # [bruce 080912 moved this here from part of a method in class GLPane.
        #  In this code's old location, Mark wrote [2007-06-01]: "Problem -
        #  I don't believe this text is processed by fix_whatsthis_text_and_links()
        #  in whatsthis_utilities.py." Now that this code is here, I don't know
        #  whether that's still true. ]
        from ne1_ui.WhatsThisText_for_MainWindow import whats_this_text_for_glpane
        self.glpane.setWhatsThis( whats_this_text_for_glpane() )

        # update [re the above comment], bruce 081209:
        # I added the following explicit call of fix_whatsthis_text_and_links,
        # but it doesn't work to replace Ctrl with Cmd on Mac;
        # see today's comment in fix_whatsthis_text_and_links for likely reason.
        # So I will leave this here, but also leave in place the kluges
        # in whats_this_text_for_glpane to do that replacement itself.
        # The wiki help link in this whatsthis text doesn't work,
        # but I guess that is an independent issue, related to lack
        # of use of class QToolBar_WikiHelp or similar code, for GLPane
        # or this class or the main window class.
        from foundation.whatsthis_utilities import fix_whatsthis_text_and_links
        fix_whatsthis_text_and_links(self.glpane) # doesn't yet work

        self.pwProjectTabWidget.KLUGE_setGLPane(self.glpane)
            # help fix bug 2522 [bruce 070829]
        qt4warnDestruction(self.glpane, 'GLPane of PartWindow')
        pwSplitter.addWidget(self.glpane)

        # ##################################################################
        # <pwBottomArea> is a container at the bottom of the part window
        # spanning its entire width. It is intended to be used as an extra
        # area for use by Property Managers (or anything else) that needs
        # a landscape oriented layout.
        # An example is the Sequence Editor, which is part of the
        # Strand Properties PM.
        self.pwBottomArea = QFrame()
            # IMHO, self is not a good parent. Mark 2008-01-04.
        pwBottomArea = self.pwBottomArea
        pwBottomArea.setObjectName("pwBottomArea")
        pwBottomArea.setMaximumHeight(50)

        # Add a frame border to see what it looks like.
        pwBottomArea.setFrameStyle( QFrame.Panel | QFrame.Sunken )

        self.pwVBoxLayout.addWidget(pwBottomArea)

        # Hide the bottom frame for now. Later this might be used for the
        # sequence editor.
        pwBottomArea.hide()

        #This widget implementation is subject to heavy revision. The purpose
        #is to implement a NFR that Mark urgently needs : The NFR is: Need a
        #way to quickly find a node in the MT by entering its name.
        #-- Ninad 2008-11-06
        self.pwSpecialDockWidgetInLeftChannel = SelectNodeByNameDockWidget(self.glpane.win)
        leftChannelVBoxLayout.addWidget(self.pwSpecialDockWidgetInLeftChannel)

        # See the resizeEvent() docstring for more information about
        # resizeTimer.
        self.resizeTimer = QTimer(self)
        self.resizeTimer.setSingleShot(True)
        return

    def getLeftChannelDockWidget(self):
        return self.pwSpecialDockWidgetInLeftChannel

    def updateWindowTitle(self, changed = False):
        #by mark; bruce 050810 revised this in several ways, fixed bug 785
        """
        Update the window title (caption) at the top of the part window.
        Example:  "partname.mmp"

        This implements the standard way most applications indicate that a
        document has unsaved changes. On Mac OS X the close button will have
        a modified look; on other platforms the window title will have
        an '*' (asterisk).

        @note: We'll want to experiment with this to make sure it

        @param changed: If True, the document has unsaved changes.
        @type  changed: boolean

        @see: U{B{windowTitle}<http://doc.trolltech.com/4/qwidget.html#windowTitle-prop>},
              U{B{windowModified}<http://doc.trolltech.com/4/qwidget.html#windowModified-prop>}
        """
        # WARNING: there is mostly-duplicated code in this method and in
        # MWsemantics.update_mainwindow_caption. See the comment in that
        # method for more info and todos. [bruce 081227 comment]
        caption_fullpath = env.prefs[captionFullPath_prefs_key]

        partname = "Untitled" # fallback value if no file yet
        if self.assy.filename: #bruce 081227 cleanup: try -> if, etc
            # self.assy.filename is always an empty string, even after a
            # file has been opened with a complete name. Need to ask Bruce
            # about this problem, resulting in a bug (i.e. the window title
            # is always "Untitled". Mark 2008-01-02.
            junk, basename = os.path.split(self.assy.filename)
            if basename:
                if caption_fullpath:
                    partname = os.path.normpath(self.assy.filename)
                        #fixed bug 453-1 ninad060721
                else:
                    partname = basename

        # WARNING: the following code differs in the two versions
        # of this routine.
        # The "[*]" placeholder below is modified or removed by Qt; see:
        # http://doc.trolltech.com/4/qwidget.html#windowModified-prop
        self.setWindowTitle(self.trUtf8(partname + '[*]'))
        self.setWindowModified(changed) # replaces '[*]' by '' or '*'
        return

    def collapseLeftArea(self, hideLeftArea = True):
        """
        Make the left area collapsible (via the splitter). The left area
        will be hidden (collapsed,actually) if I{hideLeftArea} is True
        (the default).
        """
        self._previous_splitterPosition = self.pwLeftArea.width()
        if hideLeftArea:
            self.pwSplitter.setCollapsible(0, True)
            self.setSplitterPosition(pos = 0)
        return

    def expandLeftArea(self):
        """
        Expand the left area.

        @see: L{MWsemantics._showFullScreenCommonCode()} for an example
        showing how it is used.
        """
        self.setSplitterPosition(pos = self._previous_splitterPosition)
        self.pwSplitter.setCollapsible(0, False)
        self.pwLeftArea.setMinimumWidth(PM_MINIMUM_WIDTH)
        self.pwLeftArea.setMaximumWidth(PM_MAXIMUM_WIDTH)
        return

    def updatePropertyManagerTab(self, tab): #Ninad 061207
        "Update the Properties Manager tab with 'tab' "

        self.parent.glpane.gl_update_confcorner()
            #bruce 070627, since PM affects confcorner appearance

        if self.propertyManagerScrollArea.widget():
            # The following is necessary to get rid of those C object
            # deleted errors (and the resulting bugs)
            lastwidgetobject = self.propertyManagerScrollArea.takeWidget()
            if lastwidgetobject:
                # bruce 071018 revised this code; see my comment on same
                # code in PM_Dialog
                try:
                    lastwidgetobject.update_props_if_needed_before_closing
                except AttributeError:
                    if 1 or debug_flags.atom_debug:
                        msg1 = "Last PropMgr %r doesn't have method" % lastwidgetobject
                        msg2 =" update_props_if_needed_before_closing. That's"
                        msg3 = " OK (for now, only implemented for Plane PM). "
                        msg4 = "Ignoring Exception: "
                        print_compact_traceback(msg1 + msg2 + msg3 + msg4)
                else:
                    lastwidgetobject.update_props_if_needed_before_closing()

            lastwidgetobject.hide()
            # @ ninad 061212 perhaps hiding the widget is not needed

        self.pwProjectTabWidget.removeTab(
            self.pwProjectTabWidget.indexOf(self.propertyManagerScrollArea))

        # Set the PropertyManager tab scroll area to the appropriate widget.
        self.propertyManagerScrollArea.setWidget(tab)

        self.pwProjectTabWidget.addTab(
            self.propertyManagerScrollArea,
            geticon("ui/modeltree/Property_Manager.png"),
            "")

        self.pwProjectTabWidget.setCurrentIndex(
            self.pwProjectTabWidget.indexOf(self.propertyManagerScrollArea))
        return

    def KLUGE_current_PropertyManager(self):
        #bruce 070627; revised 070829 as part of fixing bug 2523
        """
        Return the current Property Manager widget (whether or not its tab is
        chosen, but only if it has a tab), or None if there is not one.

        @warning: This method's existence (not only its implementation)
        is a kluge, since the right way to access that would be by asking
        the "command sequencer";
        but that's not yet implemented, so this is the best we can do for now.
        Also, it would be better to get the top command and talk to it, not
        its PM (a QWidget). Also, whatever calls this will be making
        assumptions about that PM which are really only the command's business.
        So in short, every call of this is in need of cleanup once we have a
        working "command sequencer". (That's true of many things related to
        PMs, not only this method.)

        @warning: The return values are (presumably) widgets, but they can
        also be mode objects and generator objects, due to excessive use of
        multiple inheritance in the current PM code. So be careful what you
        do with them -- they might have lots of extra methods/attrs,
        and setting your own attrs in them might mess things up.
        """
        res = self.propertyManagerScrollArea.widget()
        if not hasattr(res, 'done_btn'):
            # not sure what widget this is otherwise, but it is a widget
            # (not None) for the default mode, at least on startup, so just
            # return None in this case
            return None
        # Sometimes this PM remains present from a prior command, even when
        # there is no longer a tab for the PM. As part of fixing bug 2523
        # we have to avoid returning it in that case. How we do that is a kluge,
        # but hopefully this entire kluge function can be dispensed with soon.
        # This change also fixes bug 2522 on the Mac (but not on Windows --
        # for that, we needed to intercept removeTab in separate code above).
        index = self.pwProjectTabWidget.indexOf(
            self.propertyManagerScrollArea)
        if index == -1:
            return None
        # Due to bugs in other code, sometimes the PM tab is left in place,
        # though the PM itself is hidden. To avoid finding the PM in that case,
        # also check whether it's hidden. This will fix the CC part of a new bug
        # just reported by Keith in email (when hitting Ok in DNA Gen).
        if res.isHidden(): # probably a QWidget method [bruce 080205 comment]
            return None
        return res

    def dismiss(self):
        self.parent.removePartWindow(self)
        return

    def setSplitterPosition(self, pos = PM_DEFAULT_WIDTH, setDefault = True):
        """
        Set the position of the splitter between the left area and graphics area
        so that the width of the container holding the model tree (and
        property manager) is I{pos} pixels wide.

        @param pos: The splitter position (in pixel units).
        @type  pos: int

        @param setDefault: If True (the default), I{pos} becomes the new default
                           position.
        @type  setDefault: boolean
        """
        self.pwSplitter.moveSplitter(pos, 1)
        if _DEBUG:
            print "New Splitter Position: %d (setDefault=%d)" \
                  % (pos, setDefault)
        if setDefault:
            self.splitterPosition = pos
        return

    def resizeEvent(self, event):
        """
        This reimplementation of QWidget.resizeEvent is here to deal with the
        undesired behavior of the splitter while resizing the part window.
        Normally, the splitter will drift back and forth while resizing
        the part window. This forces the splitter to stay fixed during
        resize operations.
        """
        # When self.resizeTimer.isActive() = True, the partwindow is being
        # resized. This is checked by the resizeEvent handler in LeftFrame
        # to determine if the splitter is being moved by the user or
        # programmably by self's resizeEvent.
        if self.resizeTimer.isActive():
            self.resizeTimer.stop() # Stop the timer.
        self.resizeTimer.start( 500 )  # (Re)strand a .5 second singleshot timer.
        self.setSplitterPosition(self.splitterPosition, setDefault = False)
        QWidget.resizeEvent(self, event)
        return