import bpy
from math import degrees


def get_local_orientation(pose_bone):
	local_orientation = pose_bone.matrix_channel.to_euler()

	if pose_bone.parent is None:
		return (local_orientation.x, local_orientation.y, local_orientation.z)
	else:
		my_orientation = pose_bone.matrix_channel.copy()
		parent_orientation = pose_bone.parent.matrix_channel.copy()

		my_orientation.invert()
		orientation = (my_orientation * parent_orientation).to_euler()

	return (orientation.x, orientation.y, orientation.z)

def get_joint_angles(context):
	arm = context.scene.objects['Armature']
	pose = arm.pose
	bones = pose.bones
	joint_names = ['Base','Shoulder','Elbow','Wrist1','Wrist2','Wrist3']
	axis_index = {
	   'Base': 2,
	   'Shoulder': 1,
	   'Elbow': 1,
	   'Wrist1': 1,
	   'Wrist2': 2,
	   'Wrist3': 1,
	  }
	axis_correction = {
	    'Base': (1, 0),
	    'Shoulder': (-1, -math.pi/2),
	    'Elbow': (-1, 0),
	    'Wrist1': (-1, -math.pi/2),
	    'Wrist2': (-1, 0),
	    'Wrist3': (-1, 0),
	  }
	joint_angles_by_name = {}
	for bone in bones:
		joint_angles_by_name[bone.name] = get_local_orientation(bone)

	joint_angles = []
	for name in joint_names:
		bl_angle = joint_angles_by_name[name][axis_index[name]]
		direction, offset = axis_correction[name]
		joint_angle = direction * bl_angle + offset
		joint_angles.append(joint_angle)

	return joint_angles


class SimpleBoneAnglesPanel(bpy.types.Panel):
	bl_label = "Joint Angles"
	bl_space_type = 'VIEW_3D'
	bl_region_type = 'UI'

	def draw(self, context):
		joint_names = ['Base','Shoulder','Elbow','Wrist1','Wrist2','Wrist3']
		joint_angles = joint_angles(context)
		row = self.layout.row()
		row.label(text='test')
		#for z in range(len(joint_angles)):
			#row = self.layout.row()
			#row.label(text = joint_names[z] + ': {:.3}'.format(degrees(joint_angles[z])))
bpy.utils.register_class(SimpleBoneAnglesPanel)