#!/usr/bin/env python

"""
A test of some simple animation

this is very old-style code: don't imitate it!

"""

import wx
import numpy as np

## import local version:
import sys

#ver = 'local'
ver = 'installed'

if ver == 'installed': ## import the installed version
    from wx.lib.floatcanvas import NavCanvas
    from wx.lib.floatcanvas import FloatCanvas
    print("using installed version:", wx.lib.floatcanvas.__version__)
elif ver == 'local':
    ## import a local version
    import sys
    sys.path.append("..")
    from floatcanvas import NavCanvas
    from floatcanvas import FloatCanvas

FC = FloatCanvas

class MovingObjectMixin: # Borrowed from MovingElements.py
    """
    Methods required for a Moving object

    """

    def GetOutlinePoints(self):
        BB = self.BoundingBox
        OutlinePoints = np.array( ( (BB[0,0], BB[0,1]),
                                    (BB[0,0], BB[1,1]),
                                    (BB[1,0], BB[1,1]),
                                    (BB[1,0], BB[0,1]),
                                 )
                               )

        return OutlinePoints


class Ball(MovingObjectMixin, FloatCanvas.Circle):
    def __init__(self, XY, Velocity, Radius=2.0, **kwargs):
        self.Velocity = np.asarray(Velocity, float).reshape((2,))
        self.Radius = Radius
        self.Moving = False
        FloatCanvas.Circle.__init__(self, XY, Diameter=Radius*2, FillColor="red", **kwargs)

class DrawFrame(wx.Frame):
    def __init__(self, *args, **kwargs):
        wx.Frame.__init__(self, *args, **kwargs)

        ## Set up the MenuBar

        MenuBar = wx.MenuBar()

        file_menu = wx.Menu()
        item = file_menu.Append(wx.ID_EXIT, "","Terminate the program")
        self.Bind(wx.EVT_MENU, self.OnQuit, item)
        MenuBar.Append(file_menu, "&File")


        self.SetMenuBar(MenuBar)

        self.CreateStatusBar()
        self.SetStatusText("")

        self.Bind(wx.EVT_CLOSE, self.OnCloseWindow)

        # Add the  buttons
        ResetButton = wx.Button(self, label="Reset")
        ResetButton.Bind(wx.EVT_BUTTON, self.OnReset)

        StartButton = wx.Button(self, label="Start")
        StartButton.Bind(wx.EVT_BUTTON, self.OnStart)

        StopButton = wx.Button(self, label="Stop")
        StopButton.Bind(wx.EVT_BUTTON, self.OnStop)

        butSizer = wx.BoxSizer(wx.HORIZONTAL)
        butSizer.Add(StartButton, 0, wx.RIGHT, 5 )
        butSizer.Add(ResetButton, 0, wx.RIGHT, 5)
        butSizer.Add(StopButton, 0, )
        # Add the Canvas
        NC = NavCanvas.NavCanvas(self, -1, (500,500),
                                      Debug = False,
                                      BackgroundColor = "BLUE")

        self.Canvas = NC.Canvas
        self.Initialize(None)

        # lay it out:
        S = wx.BoxSizer(wx.VERTICAL)
        S.Add(butSizer, 0, wx.ALIGN_CENTER | wx.ALL, 5)
        S.Add(NC, 1, wx.EXPAND)
        self.SetSizer(S)

        self.timer = wx.Timer(self)
        self.Bind(wx.EVT_TIMER, self.MoveBall, self.timer)

        self.Show(True)

    def OnQuit(self,event):
        self.timer.Stop()
        self.Close(True)

    def OnCloseWindow(self, event):
        self.Destroy()

    def Initialize(self, event=None):
        Canvas = self.Canvas

        #Add the floor
        Canvas.AddLine(( (0, 0), (100, 0) ), LineWidth=4, LineColor="Black")
        # add the wall:
        Canvas.AddRectangle( (0,0), (10,50), FillColor='green')

        # add the ball:
        self.Ball = Ball( (5, 52), (2, 0), InForeground=True )
        Canvas.AddObject( self.Ball )
        # to capture the mouse to move the ball
        self.Ball.Bind(FC.EVT_FC_LEFT_DOWN, self.BallHit)
        Canvas.Bind(FC.EVT_MOTION, self.OnMove )
        Canvas.Bind(FC.EVT_LEFT_UP, self.OnLeftUp )

        wx.CallAfter(Canvas.ZoomToBB)

    def BallHit(self, object):
        print("the ball was clicked")
        self.Ball.Moving = True

    def OnMove(self, event):
        """
        Updates the status bar with the world coordinates
        and moves the object it is clicked on

        """
        self.SetStatusText("%.4f, %.4f"%tuple(event.Coords))
        if self.Ball.Moving:
            self.Ball.SetPoint(event.Coords)
            self.Canvas.Draw(True)

    def OnLeftUp(self, event):
        self.Ball.Moving = False

    def OnReset(self, event=None):
        self.Ball.SetPoint( (5, 52) )
        self.Ball.Velocity = np.array((1.5, 0.0))
        self.Canvas.Draw(True)

    def OnStart(self, event=None):
        self.timer.Start(20)

    def OnStop(self, event=None):
        self.timer.Stop()

    def MoveBall(self, event=None):
        ball = self.Ball

        dt = .1
        g = 9.806
        m = 1
        A = np.pi*(ball.Radius/100)**2 # radius in cm
        Cd = 0.47
        rho = 1.3

        if not ball.Moving: # don't do this if the user is moving it
            vel = ball.Velocity
            pos = ball.XY

            # apply drag
            vel -= np.sign(vel) * ((0.5 * Cd * rho * A * vel**2) / m * dt)
            # apply gravity
            vel[1] -= g * dt
            # move the ball
            pos += dt * vel
            # check if it's on the wall
            if pos[1] <= 52. and pos[0] <= 10.:
                #reverse velocity
                vel[1] *= -1.0
                pos[1] = 52.
            # check if it's hit the floor
            elif pos[1] <= ball.Radius:
                #reverse velocity
                vel[1] *= -1.0
                pos[1] = ball.Radius

            self.Ball.SetPoint( pos )
            self.Canvas.Draw(True)
            wx.GetApp().Yield(onlyIfNeeded=True)

class DemoApp(wx.App):
    def OnInit(self):
        frame = DrawFrame(None, -1, "Simple Drawing Window",wx.DefaultPosition, (700,700) )

        self.SetTopWindow(frame)

        return True

if __name__ == "__main__":

    app = DemoApp(0)
    app.MainLoop()