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#
#  This program is free software; you can redistribute it and/or
#  modify it under the terms of the GNU General Public License
#  as published by the Free Software Foundation; either version 2
#  of the License, or (at your option) any later version.
#
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#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
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#  along with this program; if not, write to the Free Software Foundation,
#  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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# ##### END GPL LICENSE BLOCK #####

# <pep8 compliant>

# Script copyright (C) Campbell Barton

import math
from math import radians

import bpy
import mathutils
from mathutils import Vector, Euler, Matrix


class bvh_node_class(object):
    __slots__ = (
    'name',# bvh joint name
    'parent',# bvh_node_class type or None for no parent
    'children',# a list of children of this type.
    'rest_head_world',# worldspace rest location for the head of this node
    'rest_head_local',# localspace rest location for the head of this node
    'rest_tail_world',# # worldspace rest location for the tail of this node
    'rest_tail_local',# # worldspace rest location for the tail of this node
    'channels',# list of 6 ints, -1 for an unused channel, otherwise an index for the BVH motion data lines, lock triple then rot triple
    'rot_order',# a triple of indicies as to the order rotation is applied. [0,1,2] is x/y/z - [None, None, None] if no rotation.
    'anim_data',# a list one tuple's one for each frame. (locx, locy, locz, rotx, roty, rotz)
    'has_loc',# Conveinience function, bool, same as (channels[0]!=-1 or channels[1]!=-1 channels[2]!=-1)
    'has_rot',# Conveinience function, bool, same as (channels[3]!=-1 or channels[4]!=-1 channels[5]!=-1)
    'temp')# use this for whatever you want

    def __init__(self, name, rest_head_world, rest_head_local, parent, channels, rot_order):
        self.name = name
        self.rest_head_world = rest_head_world
        self.rest_head_local = rest_head_local
        self.rest_tail_world = None
        self.rest_tail_local = None
        self.parent = parent
        self.channels = channels
        self.rot_order = rot_order

        # convenience functions
        self.has_loc = channels[0] != -1 or channels[1] != -1 or channels[2] != -1
        self.has_rot = channels[3] != -1 or channels[4] != -1 or channels[5] != -1


        self.children = []

        # list of 6 length tuples: (lx,ly,lz, rx,ry,rz)
        # even if the channels arnt used they will just be zero
        #
        self.anim_data = [(0, 0, 0, 0, 0, 0)]

    def __repr__(self):
        return 'BVH name:"%s", rest_loc:(%.3f,%.3f,%.3f), rest_tail:(%.3f,%.3f,%.3f)' %\
        (self.name,\
        self.rest_head_world.x, self.rest_head_world.y, self.rest_head_world.z,\
        self.rest_head_world.x, self.rest_head_world.y, self.rest_head_world.z)


# Change the order rotation is applied.
MATRIX_IDENTITY_3x3 = Matrix([1, 0, 0], [0, 1, 0], [0, 0, 1])
MATRIX_IDENTITY_4x4 = Matrix([1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 1, 0], [0, 0, 0, 1])


def eulerRotate(x, y, z, rot_order):
    # Clamp all values between 0 and 360, values outside this raise an error.
    mats = [Matrix.Rotation(x, 3, 'X'), Matrix.Rotation(y, 3, 'Y'), Matrix.Rotation(z, 3, 'Z')]
    return (MATRIX_IDENTITY_3x3 * mats[rot_order[0]] * (mats[rot_order[1]] * (mats[rot_order[2]]))).to_euler()

    # Should work but doesnt!
    '''
    eul = Euler((x, y, z))
    eul.order = "XYZ"[rot_order[0]] + "XYZ"[rot_order[1]] + "XYZ"[rot_order[2]]
    return tuple(eul.to_matrix().to_euler())
    '''


def read_bvh(context, file_path, ROT_MODE='XYZ', GLOBAL_SCALE=1.0):
    # File loading stuff
    # Open the file for importing
    file = open(file_path, 'rU')

    # Seperate into a list of lists, each line a list of words.
    file_lines = file.readlines()
    # Non standard carrage returns?
    if len(file_lines) == 1:
        file_lines = file_lines[0].split('\r')

    # Split by whitespace.
    file_lines = [ll for ll in [l.split() for l in file_lines] if ll]


    # Create Hirachy as empties

    if file_lines[0][0].lower() == 'hierarchy':
        #print 'Importing the BVH Hierarchy for:', file_path
        pass
    else:
        raise 'ERROR: This is not a BVH file'

    bvh_nodes = {None: None}
    bvh_nodes_serial = [None]

    channelIndex = -1


    lineIdx = 0 # An index for the file.
    while lineIdx < len(file_lines) -1:
        #...
        if file_lines[lineIdx][0].lower() == 'root' or file_lines[lineIdx][0].lower() == 'joint':

            # Join spaces into 1 word with underscores joining it.
            if len(file_lines[lineIdx]) > 2:
                file_lines[lineIdx][1] = '_'.join(file_lines[lineIdx][1:])
                file_lines[lineIdx] = file_lines[lineIdx][:2]

            # MAY NEED TO SUPPORT MULTIPLE ROOT's HERE!!!, Still unsure weather multiple roots are possible.??

            # Make sure the names are unique- Object names will match joint names exactly and both will be unique.
            name = file_lines[lineIdx][1]

            #print '%snode: %s, parent: %s' % (len(bvh_nodes_serial) * '  ', name,  bvh_nodes_serial[-1])

            lineIdx += 2 # Incriment to the next line (Offset)
            rest_head_local = Vector((float(file_lines[lineIdx][1]), float(file_lines[lineIdx][2]), float(file_lines[lineIdx][3]))) * GLOBAL_SCALE
            lineIdx += 1 # Incriment to the next line (Channels)

            # newChannel[Xposition, Yposition, Zposition, Xrotation, Yrotation, Zrotation]
            # newChannel references indecies to the motiondata,
            # if not assigned then -1 refers to the last value that will be added on loading at a value of zero, this is appended
            # We'll add a zero value onto the end of the MotionDATA so this is always refers to a value.
            my_channel = [-1, -1, -1, -1, -1, -1]
            my_rot_order = [None, None, None]
            rot_count = 0
            for channel in file_lines[lineIdx][2:]:
                channel = channel.lower()
                channelIndex += 1 # So the index points to the right channel
                if channel == 'xposition':
                    my_channel[0] = channelIndex
                elif channel == 'yposition':
                    my_channel[1] = channelIndex
                elif channel == 'zposition':
                    my_channel[2] = channelIndex

                elif channel == 'xrotation':
                    my_channel[3] = channelIndex
                    my_rot_order[rot_count] = 0
                    rot_count += 1
                elif channel == 'yrotation':
                    my_channel[4] = channelIndex
                    my_rot_order[rot_count] = 1
                    rot_count += 1
                elif channel == 'zrotation':
                    my_channel[5] = channelIndex
                    my_rot_order[rot_count] = 2
                    rot_count += 1

            channels = file_lines[lineIdx][2:]

            my_parent = bvh_nodes_serial[-1] # account for none


            # Apply the parents offset accumletivly
            if my_parent == None:
                rest_head_world = Vector(rest_head_local)
            else:
                rest_head_world = my_parent.rest_head_world + rest_head_local

            bvh_node = bvh_nodes[name] = bvh_node_class(name, rest_head_world, rest_head_local, my_parent, my_channel, my_rot_order)

            # If we have another child then we can call ourselves a parent, else
            bvh_nodes_serial.append(bvh_node)

        # Account for an end node
        if file_lines[lineIdx][0].lower() == 'end' and file_lines[lineIdx][1].lower() == 'site': # There is somtimes a name after 'End Site' but we will ignore it.
            lineIdx += 2 # Incriment to the next line (Offset)
            rest_tail = Vector((float(file_lines[lineIdx][1]), float(file_lines[lineIdx][2]), float(file_lines[lineIdx][3]))) * GLOBAL_SCALE

            bvh_nodes_serial[-1].rest_tail_world = bvh_nodes_serial[-1].rest_head_world + rest_tail
            bvh_nodes_serial[-1].rest_tail_local = bvh_nodes_serial[-1].rest_head_local + rest_tail


            # Just so we can remove the Parents in a uniform way- End end never has kids
            # so this is a placeholder
            bvh_nodes_serial.append(None)

        if len(file_lines[lineIdx]) == 1 and file_lines[lineIdx][0] == '}': # == ['}']
            bvh_nodes_serial.pop() # Remove the last item

        if len(file_lines[lineIdx]) == 1 and file_lines[lineIdx][0].lower() == 'motion':
            #print '\nImporting motion data'
            lineIdx += 3 # Set the cursor to the first frame
            break

        lineIdx += 1


    # Remove the None value used for easy parent reference
    del bvh_nodes[None]
    # Dont use anymore
    del bvh_nodes_serial

    bvh_nodes_list = bvh_nodes.values()

    while lineIdx < len(file_lines):
        line = file_lines[lineIdx]
        for bvh_node in bvh_nodes_list:
            #for bvh_node in bvh_nodes_serial:
            lx = ly = lz = rx = ry = rz = 0.0
            channels = bvh_node.channels
            anim_data = bvh_node.anim_data
            if channels[0] != -1:
                lx = GLOBAL_SCALE * float(line[channels[0]])

            if channels[1] != -1:
                ly = GLOBAL_SCALE * float(line[channels[1]])

            if channels[2] != -1:
                lz = GLOBAL_SCALE * float(line[channels[2]])

            if channels[3] != -1 or channels[4] != -1 or channels[5] != -1:
                rx, ry, rz = float(line[channels[3]]), float(line[channels[4]]), float(line[channels[5]])

                if ROT_MODE != 'NATIVE':
                    rx, ry, rz = eulerRotate(radians(rx), radians(ry), radians(rz), bvh_node.rot_order)
                else:
                    rx, ry, rz = radians(rx), radians(ry), radians(rz)

            # Done importing motion data #
            anim_data.append((lx, ly, lz, rx, ry, rz))
        lineIdx += 1

    # Assign children
    for bvh_node in bvh_nodes.values():
        bvh_node_parent = bvh_node.parent
        if bvh_node_parent:
            bvh_node_parent.children.append(bvh_node)

    # Now set the tip of each bvh_node
    for bvh_node in bvh_nodes.values():

        if not bvh_node.rest_tail_world:
            if len(bvh_node.children) == 0:
                # could just fail here, but rare BVH files have childless nodes
                bvh_node.rest_tail_world = Vector(bvh_node.rest_head_world)
                bvh_node.rest_tail_local = Vector(bvh_node.rest_head_local)
            elif len(bvh_node.children) == 1:
                bvh_node.rest_tail_world = Vector(bvh_node.children[0].rest_head_world)
                bvh_node.rest_tail_local = bvh_node.rest_head_local + bvh_node.children[0].rest_head_local
            else:
                # allow this, see above
                #if not bvh_node.children:
                #	raise 'error, bvh node has no end and no children. bad file'

                # Removed temp for now
                rest_tail_world = Vector((0.0, 0.0, 0.0))
                rest_tail_local = Vector((0.0, 0.0, 0.0))
                for bvh_node_child in bvh_node.children:
                    rest_tail_world += bvh_node_child.rest_head_world
                    rest_tail_local += bvh_node_child.rest_head_local

                bvh_node.rest_tail_world = rest_tail_world * (1.0 / len(bvh_node.children))
                bvh_node.rest_tail_local = rest_tail_local * (1.0 / len(bvh_node.children))

        # Make sure tail isnt the same location as the head.
        if (bvh_node.rest_tail_local - bvh_node.rest_head_local).length <= 0.001 * GLOBAL_SCALE:
            bvh_node.rest_tail_local.y = bvh_node.rest_tail_local.y + GLOBAL_SCALE / 10
            bvh_node.rest_tail_world.y = bvh_node.rest_tail_world.y + GLOBAL_SCALE / 10

    return bvh_nodes


def bvh_node_dict2objects(context, bvh_nodes, IMPORT_START_FRAME=1, IMPORT_LOOP=False):

    if IMPORT_START_FRAME < 1:
        IMPORT_START_FRAME = 1

    scn = context.scene
    scn.objects.selected = []

    objects = []

    def add_ob(name):
        ob = scn.objects.new('Empty', None)
        objects.append(ob)
        return ob

    # Add objects
    for name, bvh_node in bvh_nodes.items():
        bvh_node.temp = add_ob(name)

    # Parent the objects
    for bvh_node in bvh_nodes.values():
        bvh_node.temp.makeParent([bvh_node_child.temp for bvh_node_child in bvh_node.children], 1, 0) # ojbs, noninverse, 1 = not fast.

    # Offset
    for bvh_node in bvh_nodes.values():
        # Make relative to parents offset
        bvh_node.temp.loc = bvh_node.rest_head_local

    # Add tail objects
    for name, bvh_node in bvh_nodes.items():
        if not bvh_node.children:
            ob_end = add_ob(name + '_end')
            bvh_node.temp.makeParent([ob_end], 1, 0) # ojbs, noninverse, 1 = not fast.
            ob_end.loc = bvh_node.rest_tail_local


    # Animate the data, the last used bvh_node will do since they all have the same number of frames
    for frame_current in range(len(bvh_node.anim_data)):
        Blender.Set('curframe', frame_current + IMPORT_START_FRAME)

        for bvh_node in bvh_nodes.values():
            lx, ly, lz, rx, ry, rz = bvh_node.anim_data[frame_current]

            rest_head_local = bvh_node.rest_head_local
            bvh_node.temp.loc = rest_head_local + Vector((lx, ly, lz))

            bvh_node.temp.rot = rx, ry, rz

            bvh_node.temp.insertIpoKey(Blender.Object.IpoKeyTypes.LOCROT) # XXX invalid

    scn.update(1)
    return objects


def bvh_node_dict2armature(context, bvh_nodes, ROT_MODE='XYZ', IMPORT_START_FRAME=1, IMPORT_LOOP=False):

    if IMPORT_START_FRAME < 1:
        IMPORT_START_FRAME = 1

    # Add the new armature,
    scn = context.scene
#XXX	scn.objects.selected = []
    for ob in scn.objects:
        ob.select = False

    scn.frame_set(IMPORT_START_FRAME)

    arm_data = bpy.data.armatures.new("MyBVH")
    arm_ob = bpy.data.objects.new("MyBVH", arm_data)

    scn.objects.link(arm_ob)

    arm_ob.select = True
    scn.objects.active = arm_ob
    print(scn.objects.active)

    bpy.ops.object.mode_set(mode='OBJECT', toggle=False)
    bpy.ops.object.mode_set(mode='EDIT', toggle=False)


    # Get the average bone length for zero length bones, we may not use this.
    average_bone_length = 0.0
    nonzero_count = 0
    for bvh_node in bvh_nodes.values():
        l = (bvh_node.rest_head_local - bvh_node.rest_tail_local).length
        if l:
            average_bone_length += l
            nonzero_count += 1

    # Very rare cases all bones couldbe zero length???
    if not average_bone_length:
        average_bone_length = 0.1
    else:
        # Normal operation
        average_bone_length = average_bone_length / nonzero_count


#XXX - sloppy operator code

    bpy.ops.armature.delete()
    bpy.ops.armature.select_all()
    bpy.ops.armature.delete()

    ZERO_AREA_BONES = []
    for name, bvh_node in bvh_nodes.items():
        # New editbone
        bpy.ops.armature.bone_primitive_add(name="Bone")

        bone = bvh_node.temp = arm_data.edit_bones[-1]

        bone.name = name
#		arm_data.bones[name]= bone

        bone.head = bvh_node.rest_head_world
        bone.tail = bvh_node.rest_tail_world

        # ZERO AREA BONES.
        if (bone.head - bone.tail).length < 0.001:
            if bvh_node.parent:
                ofs = bvh_node.parent.rest_head_local - bvh_node.parent.rest_tail_local
                if ofs.length: # is our parent zero length also?? unlikely
                    bone.tail = bone.tail + ofs
                else:
                    bone.tail.y = bone.tail.y + average_bone_length
            else:
                bone.tail.y = bone.tail.y + average_bone_length

            ZERO_AREA_BONES.append(bone.name)


    for bvh_node in bvh_nodes.values():
        if bvh_node.parent:
            # bvh_node.temp is the Editbone

            # Set the bone parent
            bvh_node.temp.parent = bvh_node.parent.temp

            # Set the connection state
            if not bvh_node.has_loc and\
            bvh_node.parent and\
            bvh_node.parent.temp.name not in ZERO_AREA_BONES and\
            bvh_node.parent.rest_tail_local == bvh_node.rest_head_local:
                bvh_node.temp.use_connect = True

    # Replace the editbone with the editbone name,
    # to avoid memory errors accessing the editbone outside editmode
    for bvh_node in bvh_nodes.values():
        bvh_node.temp = bvh_node.temp.name

#XXX	arm_data.update()

    # Now Apply the animation to the armature

    # Get armature animation data
    bpy.ops.object.mode_set(mode='OBJECT', toggle=False)
    bpy.ops.object.mode_set(mode='POSE', toggle=False)

    pose = arm_ob.pose
    pose_bones = pose.bones

    if ROT_MODE == 'NATIVE':
        eul_order_lookup = {\
            (0, 1, 2): 'XYZ',
            (0, 2, 1): 'XZY',
            (1, 0, 2): 'YXZ',
            (1, 2, 0): 'YZX',
            (2, 0, 1): 'ZXY',
            (2, 1, 0): 'ZYX'}

        for bvh_node in bvh_nodes.values():
            bone_name = bvh_node.temp # may not be the same name as the bvh_node, could have been shortened.
            pose_bone = pose_bones[bone_name]
            pose_bone.rotation_mode = eul_order_lookup[tuple(bvh_node.rot_order)]

    elif ROT_MODE != 'QUATERNION':
        for pose_bone in pose_bones:
            pose_bone.rotation_mode = ROT_MODE
    else:
        # Quats default
        pass

    context.scene.update()

    bpy.ops.pose.select_all() # set
    bpy.ops.anim.keyframe_insert_menu(type=-4) # XXX -     -4 ???


#XXX	action = Blender.Armature.NLA.NewAction("Action")
#XXX	action.setActive(arm_ob)

    #bpy.ops.action.new()
    #action = bpy.data.actions[-1]

    # arm_ob.animation_data.action = action
    action = arm_ob.animation_data.action

    # Replace the bvh_node.temp (currently an editbone)
    # With a tuple  (pose_bone, armature_bone, bone_rest_matrix, bone_rest_matrix_inv)
    for bvh_node in bvh_nodes.values():
        bone_name = bvh_node.temp # may not be the same name as the bvh_node, could have been shortened.
        pose_bone = pose_bones[bone_name]
        rest_bone = arm_data.bones[bone_name]
        bone_rest_matrix = rest_bone.matrix_local.rotation_part()


        bone_rest_matrix_inv = Matrix(bone_rest_matrix)
        bone_rest_matrix_inv.invert()

        bone_rest_matrix_inv.resize4x4()
        bone_rest_matrix.resize4x4()
        bvh_node.temp = (pose_bone, bone, bone_rest_matrix, bone_rest_matrix_inv)


    # Make a dict for fast access without rebuilding a list all the time.

    # KEYFRAME METHOD, SLOW, USE IPOS DIRECT
    # TODO: use f-point samples instead (Aligorith)

    if ROT_MODE != 'QUATERNION':
        prev_euler = [Euler() for i in range(len(bvh_nodes))]

    # Animate the data, the last used bvh_node will do since they all have the same number of frames
    for frame_current in range(len(bvh_node.anim_data)-1): # skip the first frame (rest frame)
        # print frame_current

        # if frame_current==40: # debugging
        # 	break

        # Dont neet to set the current frame
        for i, bvh_node in enumerate(bvh_nodes.values()):
            pose_bone, bone, bone_rest_matrix, bone_rest_matrix_inv = bvh_node.temp
            lx, ly, lz, rx, ry, rz = bvh_node.anim_data[frame_current + 1]

            if bvh_node.has_rot:
                bone_rotation_matrix = Euler((rx, ry, rz)).to_matrix().resize4x4()
                bone_rotation_matrix = bone_rest_matrix_inv * bone_rotation_matrix * bone_rest_matrix

                if ROT_MODE == 'QUATERNION':
                    pose_bone.rotation_quaternion = bone_rotation_matrix.to_quat()
                else:
                    euler = bone_rotation_matrix.to_euler(pose_bone.rotation_mode, prev_euler[i])
                    pose_bone.rotation_euler = euler
                    prev_euler[i] = euler

            if bvh_node.has_loc:
                pose_bone.location = (bone_rest_matrix_inv * Matrix.Translation(Vector((lx, ly, lz)) - bvh_node.rest_head_local)).translation_part()

            if bvh_node.has_loc:
                pose_bone.keyframe_insert("location")
            if bvh_node.has_rot:
                if ROT_MODE == 'QUATERNION':
                    pose_bone.keyframe_insert("rotation_quaternion")
                else:
                    pose_bone.keyframe_insert("rotation_euler")


        # bpy.ops.anim.keyframe_insert_menu(type=-4) # XXX -     -4 ???
        bpy.ops.screen.frame_offset(delta=1)

    for cu in action.fcurves:
        if IMPORT_LOOP:
            pass # 2.5 doenst have cyclic now?

        for bez in cu.keyframe_points:
            bez.interpolation = 'LINEAR'

    return arm_ob


def load(operator, context, filepath="", rotate_mode='NATIVE', scale=1.0, use_cyclic=False, frame_start=1):
    import time
    t1 = time.time()
    print('\tparsing bvh %r...' % filepath, end="")

    bvh_nodes = read_bvh(context, filepath,
            ROT_MODE=rotate_mode,
            GLOBAL_SCALE=scale)

    print('%.4f' % (time.time() - t1))
    t1 = time.time()
    print('\timporting to blender...', end="")

    bvh_node_dict2armature(context, bvh_nodes,
            ROT_MODE=rotate_mode,
            IMPORT_START_FRAME=frame_start,
            IMPORT_LOOP=use_cyclic)

    print('Done in %.4f\n' % (time.time() - t1))
    
    return {'FINISHED'}
