class NlmeansController():
    """
    s: double
    
    Denoising strength (from 1 to 30) (default 1)
    Trade-off between noise removal and detail retention. Comparable to gaussian sigma.

    p: int      patch size (from 0 to 99) (default 7)
    
    Catches larger areas reducing broader noise patterns, but costly

    pc: int     patch size for chroma planes (from 0 to 99) (default 0)
    
    r: int      research window (from 0 to 99) (default 15)
    
    Range to search for comparable patches.
    Better filtering but costly
    
    rc: int     research window for chroma planes (from 0 to 99) (default 0)

    Good values to denoise film grain that was subobtimally encoded:
    strength: float     = 2.8
    patchSize: int      = 12
    chromaPatchSize: int = 8
    researchWindow: int = 22
    chromaResearchWindow: int= 16
    """

    DEFAULT_STRENGTH: float = 2.8
    DEFAULT_PATCH_SIZE: int = 13
    DEFAULT_CHROMA_PATCH_SIZE: int = 9
    DEFAULT_RESEARCH_WINDOW: int = 23
    DEFAULT_CHROMA_RESEARCH_WINDOW: int= 17

    def __init__(self,
                parameters: str = "none",
                strength: str = "",
                patchSize: str = "",
                chromaPatchSize: str = "",
                researchWindow: str = "",
                chromaResearchWindow: str = "",
                useHardware: bool = False):

        self.__isActive = (parameters != "none"
                                or strength
                                or patchSize
                                or chromaPatchSize
                                or researchWindow
                                or chromaResearchWindow)
        self.__useHardware = useHardware

        parameterTokens = parameters.split(',')

        self.__strengthList = []
        if strength:
            strengthTokens = strength.split(',')
            for st in strengthTokens:
                try:
                    strengthValue = float(st)
                except:
                    raise ValueError('NlmeansController: Strength value has to be of type float')
                if strengthValue < 1.0 or strengthValue > 30.0:
                    raise ValueError('NlmeansController: Strength value has to be between 1.0 and 30.0')
                self.__strengthList.append(strengthValue)
        else:
            self.__strengthList = [NlmeansController.DEFAULT_STRENGTH]

        self.__patchSizeList = []
        if patchSize:
            patchSizeTokens = patchSize.split(',')
            for pst in patchSizeTokens:
                try:
                    patchSizeValue = int(pst)
                except:
                    raise ValueError('NlmeansController: Patch size value has to be of type int')
                if patchSizeValue < 0 or patchSizeValue > 99:
                    raise ValueError('NlmeansController: Patch size value has to be between 0 and 99')
                if patchSizeValue % 2 == 0:
                    raise ValueError('NlmeansController: Patch size value has to an odd number')
                self.__patchSizeList.append(patchSizeValue)
        else:
            self.__patchSizeList = [NlmeansController.DEFAULT_PATCH_SIZE]

        self.__chromaPatchSizeList = []
        if chromaPatchSize:
            chromaPatchSizeTokens = chromaPatchSize.split(',')
            for cpst in chromaPatchSizeTokens:
                try:
                    chromaPatchSizeValue = int(pst)
                except:
                    raise ValueError('NlmeansController: Chroma patch size value has to be of type int')
                if chromaPatchSizeValue < 0 or chromaPatchSizeValue > 99:
                    raise ValueError('NlmeansController: Chroma patch value has to be between 0 and 99')
                if chromaPatchSizeValue % 2 == 0:
                    raise ValueError('NlmeansController: Chroma patch value has to an odd number')
                self.__chromaPatchSizeList.append(chromaPatchSizeValue)
        else:
            self.__chromaPatchSizeList = [NlmeansController.DEFAULT_CHROMA_PATCH_SIZE]

        self.__researchWindowList = []
        if researchWindow:
            researchWindowTokens = researchWindow.split(',')
            for rwt in researchWindowTokens:
                try:
                    researchWindowValue = int(rwt)
                except:
                    raise ValueError('NlmeansController: Research window value has to be of type int')
                if researchWindowValue < 0 or researchWindowValue > 99:
                    raise ValueError('NlmeansController: Research window value has to be between 0 and 99')
                if researchWindowValue % 2 == 0:
                    raise ValueError('NlmeansController: Research window value has to an odd number')
                self.__researchWindowList.append(researchWindowValue)
        else:
            self.__researchWindowList = [NlmeansController.DEFAULT_RESEARCH_WINDOW]

        self.__chromaResearchWindowList = []
        if chromaResearchWindow:
            chromaResearchWindowTokens = chromaResearchWindow.split(',')
            for crwt in chromaResearchWindowTokens:
                try:
                    chromaResearchWindowValue = int(crwt)
                except:
                    raise ValueError('NlmeansController: Chroma research window value has to be of type int')
                if chromaResearchWindowValue < 0 or chromaResearchWindowValue > 99:
                    raise ValueError('NlmeansController: Chroma research window value has to be between 0 and 99')
                if chromaResearchWindowValue % 2 == 0:
                    raise ValueError('NlmeansController: Chroma research window value has to an odd number')
                self.__chromaResearchWindowList.append(chromaResearchWindowValue)
        else:
            self.__chromaResearchWindowList = [NlmeansController.DEFAULT_CHROMA_RESEARCH_WINDOW]

    def isActive(self):
        return self.__isActive

    def generateDenoiseTokens(self):
        filterName = 'nlmeans_opencl' if self.__useHardware else 'nlmeans'
        return ['-vf', f"{filterName}=s={self.__strengthList[0]}"
                + f":p={self.__patchSizeList[0]}"
                + f":pc={self.__chromaPatchSizeList[0]}"
                + f":r={self.__researchWindowList[0]}"
                + f":rc={self.__chromaResearchWindowList[0]}"] if self.__isActive else []