from pylab import *
from direct_linear import curve_editing_1d
from myarray import *


# for a mouse click at (xdata, ydata)
# determine the closest curve sample point on the x axis 
# if the click is outside the plot area, return None
def get_index(event):
    global h,steps
    if event.xdata != None and event.ydata != None:
        fixed_index = int(round(event.xdata/h))
        fixed_index = max(1, min(steps,fixed_index))
    else:
        fixed_index = None
    return fixed_index

# on mouse button down, enable mouse motion callback
# and update the curve
def on_press(event):
    global motion_id, deformed
    fixed_index = get_index(event)
    if fixed_index != None and fabs(event.ydata - deformed[fixed_index]) < h:
        # enable callback for dragging
        motion_id = connect('motion_notify_event', on_motion)
        print('press', event.xdata, event.ydata,deformed[fixed_index])
        # change fixed point
        fixed = {fixed_index:event.ydata}
        # recompute the curve, and update curve data in the plot object
        deformed = curve_editing_1d(fixed, undeformed, h)
        plt.set_ydata(deformed)
        draw()

# on mouse button release, desable motion callback
def on_release(event):
    global motion_id
    disconnect(motion_id)

# mouse motion callback: update fixed point position,
# recompute the curve and redraw the plot
def on_motion(event):
    global deformed
    fixed_index = get_index(event)
    if fixed_index != None:
        fixed = {fixed_index:event.ydata}
        deformed = curve_editing_1d(fixed, undeformed, h)
        plt.set_ydata(deformed)
        draw()

# number of sample points on the curve
steps = 100
# initial positions of curve points: all zeros
# in this version of the code, only the first and the last 2 are used
undeformed = zerosf(steps+1)
# step
h = 1
# intial position for a fixed point in the center
fixed = {steps//2: 1.0}
# solve for positions satisfying this constraint
deformed = curve_editing_1d(fixed, undeformed, h)
# plot returns a list of plot handles, in our case, just one
plt = plot(deformed)[0]
# initially, no callback for mouse motion
motion_id = 0
# callback for mouse button press and release
press_id = connect('button_press_event', on_press)
release_id = connect('button_release_event', on_release)
show()