#!/usr/bin/env python
# -*- coding: utf-8 -*-

"""Display an image on `psycopy.visual.Window`"""

# Part of the PsychoPy library
# Copyright (C) 2002-2018 Jonathan Peirce (C) 2019-2022 Open Science Tools Ltd.
# Distributed under the terms of the GNU General Public License (GPL).

# Ensure setting pyglet.options['debug_gl'] to False is done prior to any
# other calls to pyglet or pyglet submodules, otherwise it may not get picked
# up by the pyglet GL engine and have no effect.
# Shaders will work but require OpenGL2.0 drivers AND PyOpenGL3.0+
import pyglet

from psychopy.layout import Size

pyglet.options['debug_gl'] = False
import ctypes
GL = pyglet.gl

import numpy
from fractions import Fraction

import psychopy  # so we can get the __path__
from psychopy import logging, colors, layout

from psychopy.tools.attributetools import attributeSetter, setAttribute
from psychopy.visual.basevisual import (
    BaseVisualStim, DraggingMixin, ContainerMixin, ColorMixin, TextureMixin
)


class ImageStim(BaseVisualStim, DraggingMixin, ContainerMixin, ColorMixin,
                TextureMixin):
    """Display an image on a :class:`psychopy.visual.Window`
    """

    def __init__(self,
                 win,
                 image=None,
                 mask=None,
                 units="",
                 pos=(0.0, 0.0),
                 size=None,
                 anchor="center",
                 ori=0.0,
                 color=(1.0, 1.0, 1.0),
                 colorSpace='rgb',
                 contrast=1.0,
                 opacity=None,
                 depth=0,
                 interpolate=False,
                 draggable=False,
                 flipHoriz=False,
                 flipVert=False,
                 texRes=128,
                 name=None,
                 autoLog=None,
                 maskParams=None):
        """ """  # Empty docstring. All doc is in attributes
        # what local vars are defined (these are the init params) for use by
        # __repr__
        self._initParams = dir()
        self._initParams.remove('self')

        super(ImageStim, self).__init__(win, units=units, name=name,
                                        autoLog=False)  # set at end of init
        self.draggable = draggable
        # use shaders if available by default, this is a good thing
        self.__dict__['useShaders'] = win._haveShaders

        # initialise textures for stimulus
        self._texID = GL.GLuint()
        GL.glGenTextures(1, ctypes.byref(self._texID))
        self._maskID = GL.GLuint()
        GL.glGenTextures(1, ctypes.byref(self._maskID))
        self._pixbuffID = GL.GLuint()
        GL.glGenBuffers(1, ctypes.byref(self._pixbuffID))
        self.__dict__['maskParams'] = maskParams
        self.__dict__['mask'] = mask
        # Not pretty (redefined later) but it works!
        self.__dict__['texRes'] = texRes

        # Other stuff
        self._imName = image
        self.isLumImage = None
        self.interpolate = interpolate
        self.vertices = None
        self.anchor = anchor
        self.flipHoriz = flipHoriz
        self.flipVert = flipVert
        self._requestedSize = size
        self._origSize = None  # updated if an image texture gets loaded
        self.size = size
        self.pos = numpy.array(pos, float)
        self.ori = float(ori)
        self.depth = depth

        # color and contrast etc
        self.rgbPedestal = [0, 0, 0] # does an rgb pedestal make sense for an image?
        self.colorSpace = colorSpace  # omit decorator
        self.color = color
        self.contrast = float(contrast)
        self.opacity = opacity

        # Set the image and mask-
        self.setImage(image, log=False)
        self.texRes = texRes  # rebuilds the mask
        self.size = size

        # generate a displaylist ID
        self._listID = GL.glGenLists(1)
        self._updateList()  # ie refresh display list

        # set autoLog now that params have been initialised
        wantLog = autoLog is None and self.win.autoLog
        self.__dict__['autoLog'] = autoLog or wantLog
        if self.autoLog:
            logging.exp("Created %s = %s" % (self.name, str(self)))

    def _updateListShaders(self):
        """
        The user shouldn't need this method since it gets called
        after every call to .set() Basically it updates the OpenGL
        representation of your stimulus if some parameter of the
        stimulus changes. Call it if you change a property manually
        rather than using the .set() command
        """
        self._needUpdate = False
        GL.glNewList(self._listID, GL.GL_COMPILE)

        # setup the shaderprogram
        if self.isLumImage:
            # for a luminance image do recoloring
            _prog = self.win._progSignedTexMask
            GL.glUseProgram(_prog)
            # set the texture to be texture unit 0
            GL.glUniform1i(GL.glGetUniformLocation(_prog, b"texture"), 0)
            # mask is texture unit 1
            GL.glUniform1i(GL.glGetUniformLocation(_prog, b"mask"), 1)
        else:
            # for an rgb image there is no recoloring
            _prog = self.win._progImageStim
            GL.glUseProgram(_prog)
            # set the texture to be texture unit 0
            GL.glUniform1i(GL.glGetUniformLocation(_prog, b"texture"), 0)
            # mask is texture unit 1
            GL.glUniform1i(GL.glGetUniformLocation(_prog, b"mask"), 1)

        # mask
        GL.glActiveTexture(GL.GL_TEXTURE1)
        GL.glBindTexture(GL.GL_TEXTURE_2D, self._maskID)
        GL.glEnable(GL.GL_TEXTURE_2D)  # implicitly disables 1D

        # main texture
        GL.glActiveTexture(GL.GL_TEXTURE0)
        GL.glBindTexture(GL.GL_TEXTURE_2D, self._texID)
        GL.glEnable(GL.GL_TEXTURE_2D)

        # access just once because it's slower than basic property
        vertsPix = self.verticesPix
        GL.glBegin(GL.GL_QUADS)  # draw a 4 sided polygon
        # right bottom
        GL.glMultiTexCoord2f(GL.GL_TEXTURE0, 1, 0)
        GL.glMultiTexCoord2f(GL.GL_TEXTURE1, 1, 0)
        GL.glVertex2f(vertsPix[0, 0], vertsPix[0, 1])
        # left bottom
        GL.glMultiTexCoord2f(GL.GL_TEXTURE0, 0, 0)
        GL.glMultiTexCoord2f(GL.GL_TEXTURE1, 0, 0)
        GL.glVertex2f(vertsPix[1, 0], vertsPix[1, 1])
        # left top
        GL.glMultiTexCoord2f(GL.GL_TEXTURE0, 0, 1)
        GL.glMultiTexCoord2f(GL.GL_TEXTURE1, 0, 1)
        GL.glVertex2f(vertsPix[2, 0], vertsPix[2, 1])
        # right top
        GL.glMultiTexCoord2f(GL.GL_TEXTURE0, 1, 1)
        GL.glMultiTexCoord2f(GL.GL_TEXTURE1, 1, 1)
        GL.glVertex2f(vertsPix[3, 0], vertsPix[3, 1])
        GL.glEnd()

        # unbind the textures
        GL.glActiveTexture(GL.GL_TEXTURE1)
        GL.glBindTexture(GL.GL_TEXTURE_2D, 0)
        GL.glDisable(GL.GL_TEXTURE_2D)  # implicitly disables 1D
        # main texture
        GL.glActiveTexture(GL.GL_TEXTURE0)
        GL.glBindTexture(GL.GL_TEXTURE_2D, 0)
        GL.glDisable(GL.GL_TEXTURE_2D)

        GL.glUseProgram(0)

        GL.glEndList()

    def __del__(self):
        """Remove textures from graphics card to prevent crash
        """
        try:
            if hasattr(self, '_listID'):
                GL.glDeleteLists(self._listID, 1)
            self.clearTextures()
        except (ImportError, ModuleNotFoundError, TypeError):
            pass  # has probably been garbage-collected already

    def draw(self, win=None):
        """Draw.
        """
        # check the type of image we're dealing with
        if (type(self.image) != numpy.ndarray and
                self.image in (None, "None", "none")):
            return

        # make the context for the window current
        if win is None:
            win = self.win
        self._selectWindow(win)

        # If our image is a movie stim object, pull pixel data from the most
        # recent frame and write it to the memory
        if hasattr(self.image, 'getVideoFrame'):
            videoFrame = self.image.getVideoFrame()
            if videoFrame is not None:
                self._movieFrameToTexture(videoFrame)

        GL.glPushMatrix()  # push before the list, pop after
        win.setScale('pix')
        GL.glColor4f(*self._foreColor.render('rgba1'))

        if self._needTextureUpdate:
            self.setImage(value=self._imName, log=False)
        if self._needUpdate:
            self._updateList()
        GL.glCallList(self._listID)

        # return the view to previous state
        GL.glPopMatrix()

    # overload ColorMixin methods so that they refresh the image after being called
    @property
    def foreColor(self):
        # Call setter of parent mixin
        return ColorMixin.foreColor.fget(self)

    @foreColor.setter
    def foreColor(self, value):
        # Call setter of parent mixin
        ColorMixin.foreColor.fset(self, value)
        # Reset the image and mask-
        self.setImage(self._imName, log=False)
        self.texRes = self.__dict__['texRes']  # rebuilds the mask

    @property
    def contrast(self):
        # Call setter of parent mixin
        return ColorMixin.contrast.fget(self)

    @contrast.setter
    def contrast(self, value):
        # Call setter of parent mixin
        ColorMixin.contrast.fset(self, value)
        # Reset the image and mask-
        self.setImage(self._imName, log=False)
        self.texRes = self.__dict__['texRes']  # rebuilds the mask

    @property
    def opacity(self):
        # Call setter of parent mixin
        return BaseVisualStim.opacity.fget(self)

    @opacity.setter
    def opacity(self, value):
        # Call setter of parent mixin
        BaseVisualStim.opacity.fset(self, value)
        # Reset the image and mask-
        self.setImage(self._imName, log=False)
        self.texRes = self.__dict__['texRes']  # rebuilds the mask

    def _movieFrameToTexture(self, movieSrc):
        """Convert a movie frame to a texture and use it.

        This method is used internally to copy pixel data from a camera object
        into a texture. This enables the `ImageStim` to be used as a
        'viewfinder' of sorts for the camera to view a live video stream on a
        window.

        Parameters
        ----------
        movieSrc : `~psychopy.hardware.camera.Camera`
            Movie source object.

        """
        # get the most recent video frame and extract color data
        colorData = movieSrc.colorData

        # get the size of the movie frame and compute the buffer size
        vidWidth, vidHeight = movieSrc.size
        nBufferBytes = vidWidth * vidHeight * 3

        # bind pixel unpack buffer
        GL.glBindBuffer(GL.GL_PIXEL_UNPACK_BUFFER, self._pixbuffID)

        # Free last storage buffer before mapping and writing new frame
        # data. This allows the GPU to process the extant buffer in VRAM
        # uploaded last cycle without being stalled by the CPU accessing it.
        GL.glBufferData(
            GL.GL_PIXEL_UNPACK_BUFFER,
            nBufferBytes * ctypes.sizeof(GL.GLubyte),
            None,
            GL.GL_STREAM_DRAW)

        # Map the buffer to client memory, `GL_WRITE_ONLY` to tell the
        # driver to optimize for a one-way write operation if it can.
        bufferPtr = GL.glMapBuffer(
            GL.GL_PIXEL_UNPACK_BUFFER,
            GL.GL_WRITE_ONLY)

        bufferArray = numpy.ctypeslib.as_array(
            ctypes.cast(bufferPtr, ctypes.POINTER(GL.GLubyte)),
            shape=(nBufferBytes,))

        # copy data
        bufferArray[:] = colorData[:]

        # Very important that we unmap the buffer data after copying, but
        # keep the buffer bound for setting the texture.
        GL.glUnmapBuffer(GL.GL_PIXEL_UNPACK_BUFFER)

        # bind the texture in OpenGL
        GL.glEnable(GL.GL_TEXTURE_2D)
        GL.glActiveTexture(GL.GL_TEXTURE0)
        GL.glBindTexture(GL.GL_TEXTURE_2D, self._texID)

        # copy the PBO to the texture
        GL.glPixelStorei(GL.GL_UNPACK_ALIGNMENT, 1)
        GL.glTexSubImage2D(
            GL.GL_TEXTURE_2D, 0, 0, 0,
            vidWidth, vidHeight,
            GL.GL_RGB,
            GL.GL_UNSIGNED_BYTE,
            0)  # point to the presently bound buffer

        # update texture filtering only if needed
        if self.interpolate:
            texFilter = GL.GL_LINEAR
        else:
            texFilter = GL.GL_NEAREST

        GL.glTexParameteri(
            GL.GL_TEXTURE_2D,
            GL.GL_TEXTURE_MAG_FILTER,
            texFilter)
        GL.glTexParameteri(
            GL.GL_TEXTURE_2D,
            GL.GL_TEXTURE_MIN_FILTER,
            texFilter)

        # important to unbind the PBO
        GL.glBindBuffer(GL.GL_PIXEL_UNPACK_BUFFER, 0)
        GL.glBindTexture(GL.GL_TEXTURE_2D, 0)
        GL.glDisable(GL.GL_TEXTURE_2D)

    @attributeSetter
    def image(self, value):
        """The image file to be presented (most formats supported).

        This can be a path-like object to an image file, or a numpy array of
        shape [H, W, C] where C are channels. The third dim will usually have
        length 1 (defining an intensity-only image), 3 (defining an RGB image)
        or 4 (defining an RGBA image).

        If passing a numpy array to the image attribute, the size attribute of
        ImageStim must be set explicitly.
        """
        self.__dict__['image'] = self._imName = value

        # If given a color array, get it in rgb1
        if isinstance(value, colors.Color):
            value = value.render('rgb1')

        wasLumImage = self.isLumImage
        if type(value) != numpy.ndarray and value == "color":
            datatype = GL.GL_FLOAT
        else:
            datatype = GL.GL_UNSIGNED_BYTE

        if type(value) != numpy.ndarray and value in (None, "None", "none"):
            self.isLumImage = True
        else:
            self.isLumImage = self._createTexture(
                value, id=self._texID,
                stim=self,
                pixFormat=GL.GL_RGB,
                dataType=datatype,
                maskParams=self.maskParams,
                forcePOW2=False,
                wrapping=False)

        # update size
        self.size = self._requestedSize

        if hasattr(value, 'getVideoFrame'):  # make sure we invert vertices
            self.flipVert = True

        # if we switched to/from lum image then need to update shader rule
        if wasLumImage != self.isLumImage:
            self._needUpdate = True

        self._needTextureUpdate = False

    def setImage(self, value, log=None):
        """Usually you can use 'stim.attribute = value' syntax instead,
        but use this method if you need to suppress the log message.
        """
        setAttribute(self, 'image', value, log)

    @property
    def aspectRatio(self):
        """
        Aspect ratio of original image, before taking into account the `.size` attribute of this object.

        returns :
            Aspect ratio as a (w, h) tuple, simplified using the smallest common denominator (e.g. 1080x720 pixels
            becomes (3, 2))
        """
        # Return None if we don't have a texture yet
        if (not hasattr(self, "_origSize")) or self._origSize is None:
            return
        # Work out aspect ratio (w/h)
        frac = Fraction(*self._origSize)
        return frac.numerator, frac.denominator

    @property
    def size(self):
        return BaseVisualStim.size.fget(self)

    @size.setter
    def size(self, value):
        # store requested size
        self._requestedSize = value
        isNone = numpy.asarray(value) == None
        if (self.aspectRatio is not None) and (isNone.any()) and (not isNone.all()):
            # If only one value is None, replace it with a value which maintains aspect ratio
            pix = layout.Size(value, units=self.units, win=self.win).pix
            # Replace None value with scaled pix value
            i = isNone.argmax()
            ni = isNone.argmin()
            pix[i] = pix[ni] * self.aspectRatio[i] / self.aspectRatio[ni]
            # Recreate layout object from pix
            value = layout.Size(pix, units="pix", win=self.win)
        elif (self.aspectRatio is not None) and (isNone.all()):
            # If both values are None, use pixel size
            value = layout.Size(self._origSize, units="pix", win=self.win)

        # Do base setting
        BaseVisualStim.size.fset(self, value)

    @attributeSetter
    def mask(self, value):
        """The alpha mask that can be used to control the outer
        shape of the stimulus

                + **None**, 'circle', 'gauss', 'raisedCos'
                + or the name of an image file (most formats supported)
                + or a numpy array (1xN or NxN) ranging -1:1
        """
        self.__dict__['mask'] = value
        self._createTexture(value, id=self._maskID,
                            pixFormat=GL.GL_ALPHA,
                            dataType=GL.GL_UNSIGNED_BYTE,
                            stim=self,
                            res=self.texRes,
                            maskParams=self.maskParams,
                            forcePOW2=False,
                            wrapping=True)

    def setMask(self, value, log=None):
        """Usually you can use 'stim.attribute = value' syntax instead,
        but use this method if you need to suppress the log message.
        """
        setAttribute(self, 'mask', value, log)
