import scipy

matplotlib.interactive(True)

matplotlib.use('TkAgg')

class draw_fft_c:

    def __init__(self, filename, options):

        self.hfile = open(filename, "r")

        self.block_length = options.block

        self.start = options.start

        self.sample_rate = options.sample_rate

        self.axis_font_size = 16

        self.label_font_size = 18

        self.title_font_size = 20

        self.text_size = 22

        # Setup PLOT

        self.fig = figure(1, figsize=(16, 9), facecolor='w')

        rcParams['xtick.labelsize'] = self.axis_font_size

        rcParams['ytick.labelsize'] = self.axis_font_size

        self.text_file     = figtext(0.10, 0.94, ("File: %s" % filename), weight="heavy", size=self.text_size)

        self.text_file_pos = figtext(0.10, 0.88, "File Position: ", weight="heavy", size=self.text_size)

        self.text_block    = figtext(0.40, 0.88, ("Block Size: %d" % self.block_length),

                                     weight="heavy", size=self.text_size)

        self.text_sr       = figtext(0.60, 0.88, ("Sample Rate: %.2f" % self.sample_rate),

                                     weight="heavy", size=self.text_size)

        self.make_plots()

        self.button_left_axes = self.fig.add_axes([0.45, 0.01, 0.05, 0.05], frameon=True)

        self.button_left = Button(self.button_left_axes, "<")

        self.button_left_callback = self.button_left.on_clicked(self.button_left_click)

        self.button_right_axes = self.fig.add_axes([0.50, 0.01, 0.05, 0.05], frameon=True)

        self.button_right = Button(self.button_right_axes, ">")

        self.button_right_callback = self.button_right.on_clicked(self.button_right_click)

        self.xlim = self.sp_f.get_xlim()

        self.manager = get_current_fig_manager()

        connect('key_press_event', self.click)

        show()

    def get_data(self):

        self.text_file_pos.set_text("File Position: %d" % (self.hfile.tell()//4))

        f = scipy.fromfile(self.hfile, dtype=scipy.float32, count=self.block_length)

        #print "Read in %d items" % len(self.f)

        if(len(f) == 0):

            print "End of File"

        else:

            self.f = f

            self.time = [i*(1/self.sample_rate) for i in range(len(self.f))]

    def make_plots(self):

        # if specified on the command-line, set file pointer

        self.hfile.seek(8*self.start, 1)

        self.get_data()

        # Subplot for real and imaginary parts of signal

        self.sp_f = self.fig.add_subplot(2,1,1, position=[0.075, 0.2, 0.875, 0.6])

        self.sp_f.set_title(("Amplitude"), fontsize=self.title_font_size, fontweight="bold")

        self.sp_f.set_xlabel("Time (s)", fontsize=self.label_font_size, fontweight="bold")

        self.sp_f.set_ylabel("Amplitude (V)", fontsize=self.label_font_size, fontweight="bold")

        self.plot_f = plot(self.time, self.f, 'bo-')

        self.sp_f.set_ylim([1.5*min(self.f),

                            1.5*max(self.f)])

        draw()

    def update_plots(self):

        self.plot_f[0].set_data([self.time, self.f])

        self.sp_f.set_ylim([1.5*min(self.f),

                            1.5*max(self.f)])

        draw()

    def click(self, event):

        forward_valid_keys = [" ", "down", "right"]

        backward_valid_keys = ["up", "left"]

        if(find(event.key, forward_valid_keys)):

            self.step_forward()

        elif(find(event.key, backward_valid_keys)):

            self.step_backward()

    def button_left_click(self, event):

        self.step_backward()

    def button_right_click(self, event):

        self.step_forward()

    def step_forward(self):

        self.get_data()

        self.update_plots()

    def step_backward(self):

        # Step back in file position

        if(self.hfile.tell() >= 8*self.block_length ):

            self.hfile.seek(-8*self.block_length, 1)

        else:

            self.hfile.seek(-self.hfile.tell(),1)

        self.get_data()

        self.update_plots()

#FIXME: there must be a way to do this with a Python builtin

def find(item_in, list_search):

    for l in list_search:

        if item_in == l:

            return True

    return False

    usage="%prog: [options] input_filename"

    description = "Takes a GNU Radio floating point binary file and displays the samples versus time. You can set the block size to specify how many points to read in at a time and the start position in the file. By default, the system assumes a sample rate of 1, so in time, each sample is plotted versus the sample number. To set a true time axis, set the sample rate (-R or --sample-rate) to the sample rate used when capturing the samples."

    parser = OptionParser(conflict_handler="resolve", usage=usage, description=description)

    parser.add_option("-B", "--block", type="int", default=1000,

                      help="Specify the block size [default=%default]")

    parser.add_option("-s", "--start", type="int", default=0,

                      help="Specify where to start in the file [default=%default]")

    parser.add_option("-R", "--sample-rate", type="float", default=1.0,

                      help="Set the sampler rate of the data [default=%default]")

    dc = draw_fft_c(filename, options)