import math
import gtk
import gtk.gtkgl

from OpenGL.GL import *

from Line import Line
from Circle import Circle

class SketchWidget:
    def __init__(self, sketch):
        self.sketch = sketch
        try:
            # try double-buffered
            self.glconfig = gtk.gdkgl.Config(mode = (gtk.gdkgl.MODE_RGB |
                                              gtk.gdkgl.MODE_DOUBLE |
                                              gtk.gdkgl.MODE_DEPTH))
        except gtk.gdkgl.NoMatches:
            # try single-buffered
            self.glconfig = gtk.gdkgl.Config(mode = (gtk.gdkgl.MODE_RGB |
                                              gtk.gdkgl.MODE_DEPTH))

        self.widget = gtk.gtkgl.DrawingArea(self.glconfig)

        self.widget.connect_after('realize', self.init)
        self.widget.connect('configure_event', self.reshape)
        self.widget.connect('expose_event', self.draw)

    def init(self, glarea):
        # get GLContext and GLDrawable
        glcontext = glarea.get_gl_context()
        gldrawable = glarea.get_gl_drawable()

        # GL calls
        if not gldrawable.gl_begin(glcontext): return

        glLightfv(GL_LIGHT0, GL_POSITION, (1, 1, 1, 0))
        glEnable(GL_CULL_FACE)
        glEnable(GL_LIGHTING)
        glEnable(GL_LIGHT0)
        glEnable(GL_DEPTH_TEST)

        gldrawable.gl_end()

    def reshape(self, glarea, event):
        # get GLContext and GLDrawable
        glcontext = glarea.get_gl_context()
        gldrawable = glarea.get_gl_drawable()

        # GL calls
        if not gldrawable.gl_begin(glcontext): return

        x, y, width, height = glarea.get_allocation()

        glViewport(0, 0, width, height)
        glMatrixMode(GL_PROJECTION)
        glOrtho(-2, 2, -1.5, 1.5, 1.0, -1.0)

        glMatrixMode(GL_MODELVIEW)
        glLoadIdentity()

        gldrawable.gl_end()

        return True

    def draw(self, glarea, event):
        # get GLContext and GLDrawable
        glcontext = glarea.get_gl_context()
        gldrawable = glarea.get_gl_drawable()

        # GL calls
        if not gldrawable.gl_begin(glcontext): return

        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)

        for shape in self.sketch:
            if isinstance(shape, Line):
                self.drawLine(shape)
            elif isinstance(shape, Circle):
                self.drawCircle(shape)

        if gldrawable.is_double_buffered():
            gldrawable.swap_buffers()
        else:
            glFlush()

        gldrawable.gl_end()

        return True

    def drawLine(self, shape):
        self.drawFilledLine(shape.vars[0], shape.vars[1],
                shape.vars[2], shape.vars[3], 0.03)

    def drawCircle(self, shape):
        glBegin(GL_LINE_LOOP)
        for i in range(24):
            glVertex(shape.vars[0] +
                    shape.vars[2] * math.sin(i * 2 * math.pi / 24.0),
                    shape.vars[1] +
                    shape.vars[2] * math.cos(i * 2 * math.pi / 24.0))
        glEnd()

    def drawFilledLine(self, x0, y0, x1, y1, size):
        glBegin(GL_QUADS)
        angle = math.atan2(y1 - y0, x1 - x0)
        ninety = math.pi / 2
        glVertex(x0 + size * math.cos(angle + ninety),
                y0 + size * math.sin(angle + ninety))
        glVertex(x0 + size * math.cos(angle - ninety),
                y0 + size * math.sin(angle - ninety))
        glVertex(x1 + size * math.cos(angle - ninety),
                y1 + size * math.sin(angle - ninety))
        glVertex(x1 + size * math.cos(angle + ninety),
                y1 + size * math.sin(angle + ninety))
        glEnd()

    def drawFilledCircle(self, x, y, radius, steps):
        pass