#!/usr/bin/env python

#
# bbb-fusion-animate-cursor.py
#
# Script meant to be executed from Fusion console to automatically import
# cursors.xml movements as XOffset/Yoffset on a Shape Transform node.
#
# Copyright (c) 2023 Sylvain Munaut <tnt@246tNt.com>
# SPDX-License-Identifier: MIT
#

import bbb


def gen_keyframes(cursor, framerate=24, res_x=1280, res_y=720):
	mr = max(res_x, res_y)
	kx = {}
	ky = {}
	hidden = None
	lf = None

	for t,x,y in cursor:
		# Frame number
		f = round(t * framerate)

		# Hide event ?
		if (x < 0) or (y < 0):
			if lf is not None:
				kx[f-1] = { 1: lx }
				ky[f-1] = { 1: ly }
			kx[f]   = { 1: -1 }
			ky[f]   = { 1: -1 }
			hidden = True
			continue

		# Coordinate mapping
		x =  ((x - 0.5) * res_x / mr)
		y = -((y - 0.5) * res_y / mr)

		# If there was no movement for 2 seconds, hide
		if (lf is not None) and ((f - lf) >= (2 * framerate)) and not hidden:
			kx[lf + framerate - 1] = { 1: lx }
			ky[lf + framerate - 1] = { 1: ly }
			kx[lf + framerate    ] = { 1: -1 }
			ky[lf + framerate    ] = { 1: -1 }
			kx[f  - framerate    ] = { 1: -1 }
			ky[f  - framerate    ] = { 1: -1 }
			kx[f  - framerate + 1] = { 1: lx }
			ky[f  - framerate + 1] = { 1: ly }

		# If we were hidden, add keyframe just before
		if hidden:
			kx[f-1] = { 1: -1 }
			ky[f-1] = { 1: -1 }
			hidden = False

		# Add keyframes
		kx[f] = { 1: x }
		ky[f] = { 1: y }

		# Save last coord
		lx = x
		ly = y
		lf = f

	return kx, ky


def animate_cursor(cursor_file, shape_xform, width=None, height=None, framerate=None):
	# Get data
	if width is None:
		width = comp.GetPrefs("Comp.FrameFormat.Width")

	if height is None:
		height = comp.GetPrefs("Comp.FrameFormat.Height")

	if framerate is None:
		framerate = comp.GetPrefs("Comp.FrameFormat.Rate")

	# Load cursor events
	ce = bbb.parse_cursor_xml(cursor_file)

	# Generate keyframes
	kx, ky = gen_keyframes(ce, res_x=width, res_y=height, framerate=framerate)

	# Get Shape Transform and apply keyframes
	tool = comp.FindTool(shape_xform)

	bx = comp.BezierSpline()
	bx.SetKeyFrames(kx)

	by = comp.BezierSpline()
	by.SetKeyFrames(ky)

	tool.XOffset = bx
	tool.YOffset = by


# Edit the following as needed and run using comp.RunScript in the Fusion console
print("Running ...")
animate_cursor("cursor.xml", "CursorPos")
print("Done")