from PyQt4 import QtGui, QtCore
from PIL import Image


class Component(QtCore.QObject):
    '''A base class for components to inherit from'''

    # modified = QtCore.pyqtSignal(int, bool)

    def __init__(self, moduleIndex, compPos):
        super().__init__()
        self.currentPreset = None
        self.moduleIndex = moduleIndex
        self.compPos = compPos

    def __str__(self):
        return self.__doc__

    def version(self):
        # change this number to identify new versions of a component
        return 1

    def cancel(self):
        # please stop any lengthy process in response to this variable
        self.canceled = True

    def reset(self):
        self.canceled = False

    def update(self):
        self.modified.emit(self.compPos, self.savePreset())
        # read your widget values, then call super().update()

    def loadPreset(self, presetDict, presetName):
        '''Children should take (presetDict, presetName=None) as args'''

        # Use super().loadPreset(presetDict, presetName)
        # Then update your widgets using the preset dict
        self.currentPreset = presetName \
            if presetName != None else presetDict['preset']
    '''
    def savePreset(self):
        return {}
    '''
    def preFrameRender(self, **kwargs):
        for var, value in kwargs.items():
            exec('self.%s = value' % var)

    def blankFrame(self, width, height):
        return Image.new("RGBA", (width, height), (0, 0, 0, 0))

    def pickColor(self):
        dialog = QtGui.QColorDialog()
        dialog.setOption(QtGui.QColorDialog.ShowAlphaChannel, True)
        color = dialog.getColor()
        if color.isValid():
            RGBstring = '%s,%s,%s' % (
                str(color.red()), str(color.green()), str(color.blue()))
            btnStyle = "QPushButton{background-color: %s; outline: none;}" \
                % color.name()
            return RGBstring, btnStyle
        else:
            return None, None

    def RGBFromString(self, string):
        ''' turns an RGB string like "255, 255, 255" into a tuple '''
        try:
            tup = tuple([int(i) for i in string.split(',')])
            if len(tup) != 3:
                raise ValueError
            for i in tup:
                if i > 255 or i < 0:
                    raise ValueError
            return tup
        except:
            return (255, 255, 255)

    '''
    ### Reference methods for creating a new component
    ### (Inherit from this class and define these)

    def widget(self, parent):
        self.parent = parent
        page = uic.loadUi(os.path.join(
            os.path.dirname(os.path.realpath(__file__)), 'example.ui'))
        # connect widgets signals
        self.page = page
        return page

    def update(self):
        super().update()
        self.parent.drawPreview()

    def previewRender(self, previewWorker):
        width = int(previewWorker.core.settings.value('outputWidth'))
        height = int(previewWorker.core.settings.value('outputHeight'))
        image = Image.new("RGBA", (width, height), (0,0,0,0))
        return image

    def frameRender(self, moduleNo, frameNo):
        width = int(self.worker.core.settings.value('outputWidth'))
        height = int(self.worker.core.settings.value('outputHeight'))
        image = Image.new("RGBA", (width, height), (0,0,0,0))
        return image

    def cancel(self):
        self.canceled = True

    def reset(self):
        self.canceled = False
    '''

class BadComponentInit(Exception):
    def __init__(self, arg, name):
        string = \
'''################################
Mandatory argument "%s" not specified
  in %s instance initialization
###################################'''
        print(string % (arg, name))
        quit()