import matplotlib
matplotlib.use("Agg")
import matplotlib.pyplot as plt
import numpy as np


def split_title_line(title_text, max_words=5):
	"""
	A function that splits any string based on specific character
	(returning it with the string), with maximum number of words on it
	"""
	seq = title_text.split()
	return "\n".join([" ".join(seq[i:i + max_words]) for i in range(0, len(seq), max_words)])

def plot_alignment(alignment, path, title=None, split_title=False, max_len=None):
	if max_len is not None:
		alignment = alignment[:, :max_len]

	fig = plt.figure(figsize=(8, 6))
	ax = fig.add_subplot(111)

	im = ax.imshow(
		alignment,
		aspect="auto",
		origin="lower",
		interpolation="none")
	fig.colorbar(im, ax=ax)
	xlabel = "Decoder timestep"

	if split_title:
		title = split_title_line(title)

	plt.xlabel(xlabel)
	plt.title(title)
	plt.ylabel("Encoder timestep")
	plt.tight_layout()
	plt.savefig(path, format="png")
	plt.close()


def plot_spectrogram(pred_spectrogram, path, title=None, split_title=False, target_spectrogram=None, max_len=None, auto_aspect=False):
	if max_len is not None:
		target_spectrogram = target_spectrogram[:max_len]
		pred_spectrogram = pred_spectrogram[:max_len]

	if split_title:
		title = split_title_line(title)

	fig = plt.figure(figsize=(10, 8))
	# Set common labels
	fig.text(0.5, 0.18, title, horizontalalignment="center", fontsize=16)

	#target spectrogram subplot
	if target_spectrogram is not None:
		ax1 = fig.add_subplot(311)
		ax2 = fig.add_subplot(312)

		if auto_aspect:
			im = ax1.imshow(np.rot90(target_spectrogram), aspect="auto", interpolation="none")
		else:
			im = ax1.imshow(np.rot90(target_spectrogram), interpolation="none")
		ax1.set_title("Target Mel-Spectrogram")
		fig.colorbar(mappable=im, shrink=0.65, orientation="horizontal", ax=ax1)
		ax2.set_title("Predicted Mel-Spectrogram")
	else:
		ax2 = fig.add_subplot(211)

	if auto_aspect:
		im = ax2.imshow(np.rot90(pred_spectrogram), aspect="auto", interpolation="none")
	else:
		im = ax2.imshow(np.rot90(pred_spectrogram), interpolation="none")
	fig.colorbar(mappable=im, shrink=0.65, orientation="horizontal", ax=ax2)

	plt.tight_layout()
	plt.savefig(path, format="png")
	plt.close()