main_window.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""B-ASIC Scheduler-gui Module.

Contains the scheduler-gui MainWindow class for scheduling operations in an SFG.

Start main-window with start_gui().
"""
import os
import sys
from typing                 import Union
from pprint                 import pprint
from copy                   import deepcopy
from importlib.machinery    import SourceFileLoader
import inspect


# Qt/qtpy
import qtpy
from qtpy           import uic, QtCore, QtGui, QtWidgets
from qtpy.QtCore    import QCoreApplication, Qt, Slot, Signal, QSettings, QStandardPaths
from qtpy.QtGui     import QCloseEvent
from qtpy.QtWidgets import (
    QApplication, QMainWindow, QMessageBox, QFileDialog, QInputDialog, QCheckBox, QAbstractButton,
    QTableWidgetItem)

# QGraphics and QPainter imports
from qtpy.QtCore    import QRectF, QByteArray
from qtpy.QtGui     import QIcon
from qtpy.QtWidgets import QGraphicsScene, QGraphicsItemGroup

# B-ASIC
import logger
from b_asic.schedule            import Schedule
from b_asic.graph_component     import GraphComponent
from graphics_graph_item        import GraphicsGraphItem
from graphics_axes_item         import GraphicsAxesItem
from graphics_component_item    import GraphicsComponentItem

# if sys.version_info >= (3, 9):
#     List = list
#     #Dict = dict

log = logger.getLogger()
sys.excepthook = logger.handle_exceptions


# Debug struff
if __debug__:
    log.setLevel('DEBUG')

if __debug__:
    # Print some system version information
    QT_API = os.environ.get('QT_API')
    log.debug('Qt version (runtime):     {}'.format(QtCore.qVersion()))
    log.debug('Qt version (compiletime): {}'.format(QtCore.__version__))
    log.debug('QT_API:                   {}'.format(QT_API))
    if QT_API.lower().startswith('pyside'):
        import PySide2
        log.debug('PySide version:           {}'.format(PySide2.__version__))
    if QT_API.lower().startswith('pyqt'):
        from qtpy.QtCore import PYQT_VERSION_STR
        log.debug('PyQt version:             {}'.format(PYQT_VERSION_STR))
    log.debug('QtPy version:             {}'.format(qtpy.__version__))
    
    # Autocompile the .ui form to a python file.
    try:                                        # PyQt5, try autocompile
        from qtpy.uic import compileUiDir
        uic.compileUiDir('.', map=(lambda dir,file: (dir, 'ui_' + file)))
    except:
        try:                                    # PySide2, try manual compile
            import subprocess
            os_ = sys.platform
            if os_.startswith('linux'):
                cmds = ['pyside2-uic -o ui_main_window.py main_window.ui']
                for cmd in cmds:
                    subprocess.call(cmd.split())
            else:
                #TODO: Implement (startswith) 'win32', 'darwin' (MacOs)
                raise SystemExit
        except:                                 # Compile failed, look for pre-compiled file
            try:
                from ui_main_window import Ui_MainWindow
            except:                             # Everything failed, exit
                log.exception("Could not import 'Ui_MainWindow'.")
                log.exception("Can't autocompile under", QT_API, "eviroment. Try to manual compile 'main_window.ui' to 'ui/main_window_ui.py'")
                os._exit(1)


sys.path.insert(0, 'icons/')                # Needed for the compiled '*_rc.py' files in 'ui_*.py' files
from ui_main_window import Ui_MainWindow    # Only availible when the form (.ui) is compiled


# The following QCoreApplication values is used for QSettings among others
QCoreApplication.setOrganizationName('Linöping University')
QCoreApplication.setOrganizationDomain('liu.se')
QCoreApplication.setApplicationName('B-ASIC Scheduler')
#QCoreApplication.setApplicationVersion(__version__)     # TODO: read from packet __version__




class MainWindow(QMainWindow, Ui_MainWindow):
    """Schedule of an SFG with scheduled Operations."""
    _scene: QGraphicsScene
    _schedule: Union[Schedule, None]
    _graph: Union[GraphicsGraphItem, None]
    _scale: float
    _debug_rects: QGraphicsItemGroup
    _splitter_pos: int
    _splitter_min: int

    
    def __init__(self):
        """Initialize Scheduler-gui."""
        super().__init__()
        self._schedule = None
        self._graph = None
        self._scale = 75.0
        self._debug_rects = None
        
        QIcon.setThemeName('breeze')
        log.debug('themeName: \'{}\''.format(QIcon.themeName()))
        log.debug('themeSearchPaths: {}'.format(QIcon.themeSearchPaths()))
        self.setupUi(self)
        self._read_settings()
        self._init_ui()
        self._init_graphics()
        

    def _init_ui(self) -> None:
        """Initialize the ui"""
        
        # Connect signals to slots
        self.menu_load_from_file.triggered      .connect(self._load_schedule_from_pyfile)
        self.menu_close_schedule.triggered      .connect(self.close_schedule)
        self.menu_save          .triggered      .connect(self.save)
        self.menu_save_as       .triggered      .connect(self.save_as)
        self.menu_quit          .triggered      .connect(self.close)
        self.menu_node_info     .triggered      .connect(self.show_info_table)
        self.menu_exit_dialog   .triggered      .connect(self.hide_exit_dialog)
        self.actionT            .triggered      .connect(self._actionTbtn)
        self.splitter           .splitterMoved  .connect(self._splitter_moved)

        # Setup event member functions
        self.closeEvent = self._close_event
        
        # Setup info table
        self.info_table.setSpan(0, 0, 1, 2)                         # Span 'Schedule' over 2 columns
        self.info_table.setSpan(1, 0, 1, 2)                         # Span 'Operator' over 2 columns

        # Init central-widget splitter
        self._splitter_min = self.splitter.minimumSizeHint().height()
        self.splitter.setStretchFactor(0, 1)
        self.splitter.setStretchFactor(1, 0)
        self.splitter.setCollapsible(0, False)
        self.splitter.setCollapsible(1, True)

    def _init_graphics(self) -> None:
        """Initialize the QGraphics framework"""
        self._scene = QGraphicsScene()
        self._scene.addRect(0, 0, 0, 0)             # dummy rect to be able to setPos() graph
        self.view.setScene(self._scene)
        self.view.scale(self._scale, self._scale)
        GraphicsComponentItem._scale = self._scale
        GraphicsAxesItem._scale = self._scale
        self._scene.sceneRectChanged.connect(self.shrink_scene_to_min_size)

   
    @property
    def schedule(self) -> Schedule:
        """Get the current schedule."""
        return self._schedule
    

    ###############
    #### Slots ####
    ###############
    @Slot()
    def _actionTbtn(self) -> None:
        # TODO: remove
        self.schedule.plot_schedule()
        print(f'filtersChildEvents(): {self._graph.filtersChildEvents()}')
        # self._printButtonPressed('callback_pushButton()')
    
    @Slot()
    def _load_schedule_from_pyfile(self) -> None:
        """SLOT() for SIGNAL(menu_load_from_file.triggered)
        Load a python script as a module and search for a Schedule object. If
        found, opens it."""
        settings = QSettings()
        last_file = settings.value('mainwindow/last_opened_file', QStandardPaths.standardLocations(QStandardPaths.HomeLocation)[0], str)
        if not os.path.exists(last_file):               # if filename does not exist
            last_file = os.path.dirname(last_file) + '/'
            if not os.path.exists(last_file):           # if path does not exist
                last_file = QStandardPaths.standardLocations(QStandardPaths.HomeLocation)[0]

        abs_path_filename, _ = QFileDialog.getOpenFileName(self,
                                                        self.tr("Open python file"),
                                                        last_file,
                                                        self.tr("Python Files (*.py *.py3)"))
        
        if not abs_path_filename:       # return if empty filename (QFileDialog was canceled)
            return
        log.debug('abs_path_filename = {}.'.format(abs_path_filename))

        module_name = inspect.getmodulename(abs_path_filename)
        if not module_name:             # return if empty module name
            log.error('Could not load module from file \'{}\'.'.format(abs_path_filename))
            return 
        
        try:
            module = SourceFileLoader(module_name, abs_path_filename).load_module()
        except:
            log.exception('Exception occurred. Could not load module from file \'{}\'.'.format(abs_path_filename))
            return

        schedule_obj_list = dict(inspect.getmembers(module, (lambda x: isinstance(x, Schedule))))
        
        if not schedule_obj_list:       # return if no Schedule objects in script
            QMessageBox.warning(self,
                                self.tr('File not found'),
                                self.tr('Could not find any Schedule object in file \'{}\'.')
                                .format(os.path.basename(abs_path_filename)))
            log.info('Could not find any Schedule object in file \'{}\'.'
                     .format(os.path.basename(abs_path_filename)))
            del module
            return
        
        ret_tuple = QInputDialog.getItem(self,
                                         self.tr('Load object'),
                                         self.tr('Found the following Schedule object(s) in file.\n\n'
                                                 'Select an object to proceed:'),
                                         schedule_obj_list.keys(), 0, False)

        if not ret_tuple[1]:                  # User canceled the operation
            log.debug('Load schedule operation: user canceled')
            del module
            return
        
        self.open(schedule_obj_list[ret_tuple[0]])
        del module
        settings.setValue("mainwindow/last_opened_file", abs_path_filename)

    @Slot()
    def close_schedule(self) -> None:
        """SLOT() for SIGNAL(menu_close_schedule.triggered)
        Closes current schedule."""
        if self._graph:
            self._graph.signals.component_selected.disconnect(self.info_table_update_component)
            self._graph.signals.schedule_time_changed.disconnect(self.info_table_update_schedule)
            self._graph.removeSceneEventFilters(self._graph.event_items)
            self._scene.removeItem(self._graph)
            self.menu_close_schedule.setEnabled(False)
            del self._graph
            self._graph = None
            del self._schedule
            self._schedule = None
            self.info_table_clear()
        
    @Slot()
    def save(self) -> None:
        """SLOT() for SIGNAL(menu_save.triggered)
        This method save an schedule."""
        #TODO: all
        self._printButtonPressed('save_schedule()')
        self.update_statusbar(self.tr('Schedule saved successfully'))

    @Slot()
    def save_as(self) -> None:
        """SLOT() for SIGNAL(menu_save_as.triggered)
        This method save as an schedule."""
        #TODO: all
        self._printButtonPressed('save_schedule()')
        self.update_statusbar(self.tr('Schedule saved successfully'))
    
    @Slot(bool)
    def show_info_table(self, checked: bool) -> None:
        """SLOT(bool) for SIGNAL(menu_node_info.triggered)
        Takes in a boolean and hide or show the info table accordingly with
        'checked'."""
        # Note: splitter handler index 0 is a hidden splitter handle far most left, use index 1
        # settings = QSettings()
        _, max = self.splitter.getRange(1)    # tuple(min, max)
        
        if checked:
            if self._splitter_pos < self._splitter_min:
                self.splitter.moveSplitter(max - self._splitter_min, 1)
            else:
                self.splitter.moveSplitter(max - self._splitter_pos, 1)
        else:
            self.splitter.moveSplitter(max, 1)
            
    @Slot(bool)
    def hide_exit_dialog(self, checked: bool) -> None:
        """SLOT(bool) for SIGNAL(menu_exit_dialog.triggered)
        Takes in a boolean and stores 'checked' in 'hide_exit_dialog' item in
        settings."""
        s = QSettings()
        s.setValue("mainwindow/hide_exit_dialog", checked)

    @Slot(int, int)
    def _splitter_moved(self, pos: int, index: int) -> None:
        """SLOT(int, int) for SIGNAL(splitter.splitterMoved)
        Callback method used to check if the right widget (info window) 
        has collapsed. Update the checkbutton accordingly."""
        width = self.splitter.sizes()[1]
        
        if width == 0:
            if self.menu_node_info.isChecked() is True:
                self.menu_node_info.setChecked(False)
        else:
            if self.menu_node_info.isChecked() is False:
                self.menu_node_info.setChecked(True)
            self._splitter_pos = width

    @Slot(str)
    def info_table_update_component(self, op_id: str) -> None:
        """SLOT(str) for SIGNAL(_graph.signals.component_selected)
        Taked in an operator-id, first clears the 'Operator' part of the info
        table and then fill in the table with new values from the operator
        associated with 'op_id'."""
        self.info_table_clear_component()
        self._info_table_fill_component(op_id)
    
    @Slot()
    def info_table_update_schedule(self) -> None:
        """SLOT() for SIGNAL(_graph.signals.schedule_time_changed)
        Updates the 'Schedule' part of the info table."""
        self.info_table.item(1, 1).setText(str(self.schedule.schedule_time))
        
    @Slot(QRectF)
    def shrink_scene_to_min_size(self, rect: QRectF) -> None:
        """SLOT(QRectF) for SIGNAL(_scene.sceneRectChanged)
        Takes in a QRectF (unused) and shrink the scene bounding rectangle to
        it's minimum size, when the bounding rectangle signals a change in
        geometry."""
        self._scene.setSceneRect(self._scene.itemsBoundingRect())
    


    ################
    #### Events ####
    ################
    def _close_event(self, event: QCloseEvent) -> None:
        """EVENT: Replaces QMainWindow default closeEvent(QCloseEvent) event. Takes
        in a QCloseEvent and display an exit dialog, depending on
        'hide_exit_dialog' in settings."""
        s = QSettings()
        hide_dialog = s.value('mainwindow/hide_exit_dialog', False, bool)
        ret = QMessageBox.StandardButton.Yes
        
        if not hide_dialog:
            box = QMessageBox(self)
            box.setWindowTitle(self.tr('Confirm Exit'))
            box.setText('<h3>' + self.tr('Confirm Exit') + '</h3><p><br>' +
                        self.tr('Are you sure you want to exit?') +
                        '&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br></p>')
            box.setIcon(QMessageBox.Question)
            box.setStandardButtons(QMessageBox.Yes | QMessageBox.No)
            buttons: list[QAbstractButton] = box.buttons()
            buttons[0].setText(self.tr('&Exit'))
            buttons[1].setText(self.tr('&Cancel'))
            checkbox = QCheckBox(self.tr('Don\'t ask again'))
            box.setCheckBox(checkbox)
            ret = box.exec_()
        
        if ret == QMessageBox.StandardButton.Yes:
            if not hide_dialog:
                s.setValue('mainwindow/hide_exit_dialog', checkbox.isChecked())
            self._write_settings()
            log.info('Exit: {}'.format(os.path.basename(__file__)))
            event.accept()
        else:
            event.ignore()
        


    #################################
    #### Helper member functions ####
    #################################
    def _printButtonPressed(self, func_name: str) -> None:
        #TODO: remove        

        alert = QMessageBox(self)
        alert.setText("Called from " + func_name + '!')
        alert.exec_()
    
    def open(self, schedule: Schedule) -> None:
        """Takes in an Schedule and creates a GraphicsGraphItem object."""
        self.close_schedule()
        self._schedule = deepcopy(schedule)
        self._graph = GraphicsGraphItem(self.schedule)
        self._graph.setPos(1/self._scale, 1/self._scale)
        self.menu_close_schedule.setEnabled(True)
        self._scene.addItem(self._graph)
        self._graph.installSceneEventFilters(self._graph.event_items)
        self._graph.signals.component_selected.connect(self.info_table_update_component)
        self._graph.signals.schedule_time_changed.connect(self.info_table_update_schedule)
        self.info_table_fill_schedule(self.schedule)
        self.update_statusbar(self.tr('Schedule loaded successfully'))

    def update_statusbar(self, msg: str) -> None:
        """Takes in an str and write 'msg' to the statusbar with temporarily policy."""
        self.statusbar.showMessage(msg)
        
    def _write_settings(self) -> None:
        """Write settings from MainWindow to Settings."""
        s = QSettings()
        s.setValue('mainwindow/maximized',      self.isMaximized())     # window: maximized, in X11 - alwas False
        s.setValue('mainwindow/pos',            self.pos())             # window: pos
        s.setValue('mainwindow/size',           self.size())            # window: size
        s.setValue('mainwindow/state',          self.saveState())       # toolbars, dockwidgets: pos, size
        s.setValue('mainwindow/menu/node_info', self.menu_node_info.isChecked())
        s.setValue('mainwindow/splitter/state', self.splitter.saveState())
        s.setValue('mainwindow/splitter/pos',   self.splitter.sizes()[1])

        if s.isWritable():
            log.debug('Settings written to \'{}\'.'.format(s.fileName()))
        else:
            log.warning('Settings cant be saved to file, read-only.')
    
    def _read_settings(self) -> None:
        """Read settings from Settings to MainWindow."""
        s = QSettings()
        if s.value('mainwindow/maximized', defaultValue=False, type=bool):
            self.showMaximized()
        else:
            self.move(                      s.value('mainwindow/pos', self.pos()))
            self.resize(                    s.value('mainwindow/size', self.size()))
        self.restoreState(                  s.value('mainwindow/state', QByteArray()))
        self.menu_node_info.setChecked(     s.value('mainwindow/menu/node_info', True, bool))
        self.splitter.restoreState(         s.value('mainwindow/splitter/state', QByteArray()))
        self._splitter_pos = (              s.value('mainwindow/splitter/pos', 200, int))
        self.menu_exit_dialog.setChecked(   s.value('mainwindow/hide_exit_dialog', False, bool))

        log.debug('Settings read from \'{}\'.'.format(s.fileName()))
    
    def info_table_fill_schedule(self, schedule: Schedule) -> None:
        """Takes in a Schedule and fill in the 'Schedule' part of the info table
        with values from 'schedule'"""
        self.info_table.insertRow(1)
        self.info_table.insertRow(1)
        self.info_table.insertRow(1)
        self.info_table.setItem(1, 0, QTableWidgetItem('Schedule Time'))
        self.info_table.setItem(2, 0, QTableWidgetItem('Cyclic'))
        self.info_table.setItem(3, 0, QTableWidgetItem('Resolution'))
        self.info_table.setItem(1, 1, QTableWidgetItem(str(schedule.schedule_time)))
        self.info_table.setItem(2, 1, QTableWidgetItem(str(schedule.cyclic)))
        self.info_table.setItem(3, 1, QTableWidgetItem(str(schedule.resolution)))

    def _info_table_fill_component(self, op_id: str) -> None:
        """Taked in an operator-id and fill in the 'Operator' part of the info
        table with values from the operator associated with 'op_id'."""
        op: GraphComponent = self.schedule.sfg.find_by_id(op_id)
        si = self.info_table.rowCount()                                         # si = start index

        if op.graph_id:
            self.info_table.insertRow(si)
            self.info_table.setItem(si, 0, QTableWidgetItem('ID'))
            self.info_table.setItem(si, 1, QTableWidgetItem(str(op.graph_id)))
            si += 1
        if op.name:
            self.info_table.insertRow(si)
            self.info_table.setItem(si, 0, QTableWidgetItem('Name'))
            self.info_table.setItem(si, 1, QTableWidgetItem(str(op.name)))
            si += 1
        
        for key, value in op.params.items():
            self.info_table.insertRow(si)
            self.info_table.setItem(si, 0, QTableWidgetItem(key))
            self.info_table.setItem(si, 1, QTableWidgetItem(str(value)))
            si += 1
            
    
    def info_table_clear(self) -> None:
        """Clears the info table."""
        self.info_table_clear_component()
        self.info_table_clear_schedule()
    
    def info_table_clear_schedule(self) -> None:
        """Clears the schedule part of the info table."""
        row = self.info_table.findItems('Operator', Qt.MatchExactly)
        if row:
            row = row[0].row()
            if row > 2:
                for _ in range(3):
                    self.info_table.removeRow(1)
        else:
            log.error("'Operator' not found in info table. It may have been renamed.")
  
    def info_table_clear_component(self) -> None:
        """Clears the component part of the info table."""
        row = self.info_table.findItems('Operator', Qt.MatchExactly)
        if row:
            row = row[0].row()
            for _ in range(self.info_table.rowCount() - row + 1):
                    self.info_table.removeRow(row + 1)
        else:
            log.error("'Operator' not found in info table. It may have been renamed.")


def start_gui():
    app = QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec_())

if __name__ == "__main__":
    start_gui()