"""
===========
Curved text
===========

This example shows how to draw text along a circular arc with mplsoccer's
CurvedText artist. Radar uses it for curved parameter labels
(``curved=True``, see the
:ref:`radar examples <sphx_glr_gallery_radar_plot_radar.py>`), and so does
PyPizza (``curved_params=True``, see the
:ref:`pizza examples <sphx_glr_gallery_pizza_plots_plot_pizza_basic.py>`),
but you can also use it on normal axes.
"""
import matplotlib.pyplot as plt
import numpy as np

from mplsoccer import CurvedText

##############################################################################
# Text around a circle
# --------------------
# CurvedText has a similar signature to matplotlib's text: you give it a
# position (x, y) and a string. The text curves along the circle that passes
# through (x, y) around the center point (by default the origin).
# Here the text starts at 30 degrees (the red dot) and flows clockwise.
fig, ax = plt.subplots(figsize=(6, 6))
ax.set_xlim(-1.5, 1.5)
ax.set_ylim(-1.5, 1.5)
ax.set_aspect('equal')

# draw the circle the text will follow, just for reference
ax.add_patch(plt.Circle((0, 0), 1, fill=False, color='#cccccc', linestyle='--'))

# start the text at 30 degrees (0 = top, increasing clockwise)
angle = np.radians(30)
x, y = np.sin(angle), np.cos(angle)
ax.plot(x, y, 'o', color='#fc5f5f')  # mark the start point

text = CurvedText(ax, x, y, 'The quick brown fox jumps over the lazy dog',
                  align='start', fontsize=14)
text_artist = ax.add_artist(text)

##############################################################################
# Alignment
# ---------
# The align argument controls how the text sits relative to (x, y):
# ``'start'`` begins the text at the point, ``'center'`` (the default)
# centers it on the point, and ``'end'`` finishes the text at the point.
# The names refer to the text's reading direction along the arc rather than
# left/right, because the direction can flip so the text stays readable
# (see the next section).
fig, ax = plt.subplots(figsize=(6, 6))
ax.set_xlim(-1.5, 1.5)
ax.set_ylim(-1.5, 1.5)
ax.set_aspect('equal')
ax.add_patch(plt.Circle((0, 0), 1, fill=False, color='#cccccc', linestyle='--'))

for angle_degrees, align in [(60, 'start'), (0, 'center'), (-60, 'end')]:
    angle = np.radians(angle_degrees)
    x, y = np.sin(angle), np.cos(angle)
    ax.plot(x, y, 'o', color='#fc5f5f')
    text = CurvedText(ax, x, y, f'align {align}', align=align, fontsize=14)
    ax.add_artist(text)

##############################################################################
# Direction
# ---------
# By default (``direction='auto'``), text in the lower half of the circle
# flips so it reads left to right rather than upside down. You can force a
# single direction with ``'clockwise'`` or ``'counterclockwise'``.
fig, ax = plt.subplots(figsize=(6, 6))
ax.set_xlim(-1.5, 1.5)
ax.set_ylim(-1.5, 1.5)
ax.set_aspect('equal')
ax.add_patch(plt.Circle((0, 0), 1, fill=False, color='#cccccc', linestyle='--'))

text_top = CurvedText(ax, 0, 1, 'automatic direction', fontsize=14)
text_bottom = CurvedText(ax, 0, -1, 'flips to stay readable', fontsize=14)
text_forced = CurvedText(ax, 0, -1.35, 'forced clockwise', fontsize=14,
                         direction='clockwise', color='#fc5f5f')
for text in (text_top, text_bottom, text_forced):
    ax.add_artist(text)

##############################################################################
# Multiline text
# --------------
# Newlines split the text into multiple arcs. The radial_anchor argument
# controls how the lines stack relative to the circle through (x, y):
# ``'inner'`` (the default) centers the innermost line on the circle with
# further lines stacking outward, while ``'center'`` centers the block of
# lines on the circle. The letter_spacing argument adds extra space
# (in points) between the characters.
fig, ax = plt.subplots(figsize=(6, 6))
ax.set_xlim(-1.5, 1.5)
ax.set_ylim(-1.5, 1.5)
ax.set_aspect('equal')
ax.add_patch(plt.Circle((0, 0), 1, fill=False, color='#cccccc', linestyle='--'))

text_inner = CurvedText(ax, -0.87, 0.5, 'stacked\noutward', fontsize=14)
text_center = CurvedText(ax, 0.87, 0.5, 'centered\non the circle', fontsize=14,
                         radial_anchor='center')
text_spaced = CurvedText(ax, 0, -1, 'spaced out', fontsize=14, letter_spacing=6)
for text in (text_inner, text_center, text_spaced):
    ax.add_artist(text)

##############################################################################
# Polar axes
# ----------
# CurvedText also works on polar axes, where (like matplotlib's text) x is
# the angle theta in radians and y is the radius. The text curves around the
# polar origin, respecting the axes' theta direction, theta offset and
# origin radius, so it works with the pizza charts. PyPizza uses this for
# curved parameter labels via ``curved_params=True``.
fig, ax = plt.subplots(figsize=(6, 6), subplot_kw={'projection': 'polar'})
ax.set_theta_zero_location('N')  # angle zero at the top
ax.set_theta_direction(-1)  # angles increase clockwise
ax.set_rmax(1)

text_polar = CurvedText(ax, np.radians(45), 0.9, 'curved on a polar axis',
                        fontsize=14)
ax.add_artist(text_polar)

plt.show()  # If you are using a Jupyter notebook you do not need this line