import bpy
from mathutils import Vector
from mathutils.geometry import intersect_line_line_2d


def get_mat(ob):
    for sl in ob.material_slots:
        if sl.material:
            return sl.material

def link_mat_to_object(ob):
    for sl in ob.material_slots:
        m = sl.material
        sl.link = 'OBJECT'
        sl.material = m

def get_operator_from_id(idname):
    if not '.' in idname:
        return

    m, o = idname.split(".")
    try:
        op = getattr(getattr(bpy.ops, m), o)
        op.get_rna_type()
    except Exception:
        return
    
    return op
'''
def canvas_space(point,scale,offset):
    return scale*Vector(point)+Vector(offset)
'''

def get_object_color(ob):
    if not ob.data.materials:
        return
    
    mat = get_mat(ob)
    if not mat or not mat.node_tree or not mat.node_tree.nodes:
        return

    emit_node = mat.node_tree.nodes.get('Emission')
    if not emit_node:
        return
    
    return emit_node.inputs['Color'].default_value

def intersect_rectangles(bound, border):  # returns None if rectangles don't intersect
    dx = min(border[1][0],bound[1][0]) - max(border[0][0],bound[0][0])
    dy = min(border[0][1],bound[0][1]) - max(border[2][1],bound[2][1])

    if (dx>=0) and (dy>=0):
        return dx*dy

def point_inside_rectangle(point, rect):
    return rect[0][0]< point[0]< rect[1][0] and rect[2][1]< point[1]< rect[0][1]

def point_over_shape(point,verts,loops,outside_point=(-1,-1)):
    out = Vector(outside_point)
    pt = Vector(point)

    intersections = 0
    for loop in loops:
        for i,p in enumerate(loop):
            a = Vector(verts[loop[i-1]])
            b = Vector(verts[p])

            if intersect_line_line_2d(pt,out,a,b):
                intersections += 1

    if intersections%2 == 1: #chek if the nb of intersection is odd
        return True


def border_over_shape(border,verts,loops):
    for loop in loops:
        for i,p in enumerate(loop):
            a = Vector(verts[loop[i-1]])
            b = Vector(verts[p])

            for j in range(0,4):
                c = border[j-1]
                d = border[j]
                if intersect_line_line_2d(a,b,c,d):
                    return True

    for point in verts:
        if point_inside_rectangle(point,border):
            return True

    for point in border:
        if point_over_shape(point,verts,loops):
            return True



def border_loop(vert, loop):
    border_edge =[e for e in vert.link_edges if e.is_boundary]

    if border_edge:
        for edge in border_edge:
            other_vert = edge.other_vert(vert)

            if not other_vert in loop:
                loop.append(other_vert)
                border_loop(other_vert, loop)

        return loop
    else:
        return [vert]


def contour_loops(bm, vert_index=0, loops=None, vert_indices=None):
    loops = loops or []
    vert_indices = vert_indices or [v.index for v in bm.verts]

    bm.verts.ensure_lookup_table()

    loop = border_loop(bm.verts[vert_index], [bm.verts[vert_index]])
    if len(loop) >1:
        loops.append(loop)

    for v in loop:
        vert_indices.remove(v.index)

    if len(vert_indices):
        contour_loops(bm, vert_indices[0], loops, vert_indices)

    return loops


def get_IK_bones(IK_last):
    ik_chain = IK_last.parent_recursive
    ik_len = 0

    #Get IK len:
    for c in IK_last.constraints:
        if c.type == 'IK':
            ik_len = c.chain_count -2
            break

    IK_root = ik_chain[ik_len]

    IK_mid= ik_chain[:ik_len]

    IK_mid.reverse()
    IK_mid.append(IK_last)

    return IK_root,IK_mid

def find_mirror(name):
    mirror = None
    prop= False

    if name:

        if name.startswith('[')and name.endswith(']'):
            prop = True
            name= name[:-2][2:]

        match={
        'R': 'L',
        'r': 'l',
        'L': 'R',
        'l': 'r',
        }

        separator=['.','_']

        if name.startswith(tuple(match.keys())):
            if name[1] in separator:
                mirror = match[name[0]]+name[1:]

        if name.endswith(tuple(match.keys())):
            if name[-2] in separator:
                mirror = name[:-1]+match[name[-1]]

        if mirror and prop == True:
            mirror='["%s"]'%mirror

        return mirror

    else:
        return None


def is_shape(ob):
    shape = False

    if ob.hide_render:
        return shape

    if ob.type in ('MESH', 'CURVE', 'FONT'):
        if ob.rig_picker.shape_type == 'BONE':
            if ob.rig_picker.name:
                shape = True
        else:
            shape = True
    return shape

def is_over_region(self,context,event):
    inside = 2 < event.mouse_region_x < context.region.width -2 and \
    2 < event.mouse_region_y < context.region.height -2 and \
    [a for a in context.screen.areas if a.as_pointer()==self.adress] and \
    not context.screen.show_fullscreen

    return inside

def bound_box_center(ob):
    points = [ob.matrix_world@Vector(p) for p in ob.bound_box]

    x = [v[0] for v in points]
    y = [v[1] for v in points]
    z = [v[2] for v in points]

    return (sum(x) / len(points), sum(y) / len(points),sum(z) / len(points))