#!/usr/bin/env python
""" Plot with scroll and pan-zoom interaction.

Draws some x-y line and scatter plots. On the plot:
 - Scroll by dragging the scrollbar above the plot
 - Left-drag pans the plot.
 - Mousewheel up and down zooms the plot in and out.
 - Pressing "z" brings up the Zoom Box, and you can click-drag a rectangular
   region to zoom.  If you use a sequence of zoom boxes, pressing alt-left-arrow
   and alt-right-arrow moves you forwards and backwards through the "zoom
   history".
"""

# Major library imports
from numpy import linspace
from scipy.special import jn

# Enthought library imports
from enable.api import Component, ComponentEditor
from traits.api import HasTraits, Instance
from traitsui.api import Item, Group, View

# Chaco imports
from chaco.api import ArrayPlotData, VPlotContainer, Plot
from chaco.plotscrollbar import PlotScrollBar
from chaco.tools.api import PanTool, ZoomTool

# ===============================================================================
# # Create the Chaco plot.
# ===============================================================================
def _create_plot_component():

    # Create some x-y data series to plot
    x = linspace(-2.0, 10.0, 100)
    pd = ArrayPlotData(index=x)
    for i in range(5):
        pd.set_data("y" + str(i), jn(i, x))

    # Create some line plots of some of the data
    plot1 = Plot(pd, padding=50)
    plot1.plot(("index", "y0", "y1", "y2"), name="j_n, n<3", color="red")
    plot1.plot(("index", "y3"), name="j_3", color="blue")

    # Attach some tools to the plot
    plot1.tools.append(PanTool(plot1))
    zoom = ZoomTool(component=plot1, tool_mode="box", always_on=False)
    plot1.overlays.append(zoom)

    # Add the scrollbar
    hscrollbar = PlotScrollBar(
        component=plot1, axis="index", resizable="h", height=15
    )
    plot1.padding_top = 0
    # NOTE: scrollbar fails to display with index_range covering full range
    plot1.index_range.high_setting = 1
    hscrollbar.force_data_update()

    # Create a container and add our plots
    container = VPlotContainer()
    container.add(plot1)
    container.add(hscrollbar)

    return container


# ===============================================================================
# Attributes to use for the plot view.
size = (900, 500)
title = "Scrollbar example"

# ===============================================================================
# # Demo class that is used by the demo.py application.
# ===============================================================================
class Demo(HasTraits):
    plot = Instance(Component)

    traits_view = View(
        Group(
            Item("plot", editor=ComponentEditor(size=size), show_label=False),
            orientation="vertical",
        ),
        resizable=True,
        title=title,
    )

    def _plot_default(self):
        return _create_plot_component()


demo = Demo()

if __name__ == "__main__":
    demo.configure_traits()