"""Build O Image Depth Cutout."""
import bpy
from anyimage.operators.cutout_tool.shape import NORMAL_REDUCTION_ATTRIBUTE_NAME
from ..common.nodes import (
    interface_socket, group_input, float_input, read_float_attribute, read_vector_attribute,
    store_float_attribute, store_vector_attribute, remove_attribute_pattern,
    prepare_node_group, evaluate_field, compare_node,
)
from ..common.boundary_smoothing import smooth_cut_boundary
from ..common.cutout import _position_field, _shade_output
from ..common.depth_surface import _math, project_depth_surface, build_surface_camera, split_depth_surface, sample_face_camera
from ..common.smoothing import edge_boundary_field
from ..common.cutout_boundary import original_boundary_field, remove_boundary_triangles, taper_split_profile


NODE_GROUP_NAME = "O Image Depth Cutout"
SOLID_NORMAL_ATTRIBUTE = "_o_solid_normal"
BALLOON_THICKNESS_SCALE = 2.0
FRONT_INFLATION_SCALE = 0.5


def build_normal_weight(group, is_shell):
    """Use full shell smoothing and thickness-weighted balloon smoothing."""
    control = group_input(group.nodes, {"Thickness"})
    amount = group.nodes.new("GeometryNodeSwitch")
    amount.input_type = "FLOAT"
    group.links.new(is_shell, amount.inputs["Switch"])
    group.links.new(control.outputs["Thickness"], amount.inputs["False"])
    amount.inputs["True"].default_value = 1
    ramp = group.nodes.new("ShaderNodeMapRange")
    ramp.interpolation_type = "SMOOTHSTEP"
    ramp.clamp = True
    group.links.new(amount.outputs[0], ramp.inputs["Value"])
    return ramp.outputs["Result"]


def blend_normal(group, original, smoothed, weight):
    """Normalize the thickness-weighted blend on the consumer geometry."""
    mix = group.nodes.new("ShaderNodeMix")
    mix.data_type = "VECTOR"
    if isinstance(weight, (int, float)):
        mix.inputs[0].default_value = weight
    else:
        group.links.new(weight, mix.inputs[0])
    group.links.new(original, mix.inputs[4])
    group.links.new(smoothed, mix.inputs[5])
    normalize = group.nodes.new("ShaderNodeVectorMath")
    normalize.operation = "NORMALIZE"
    group.links.new(mix.outputs["Result"], normalize.inputs[0])
    return normalize.outputs[0]


def build_front_normal(group, normal_weight):
    """Smooth the projected surface normals that drive the inflation."""
    links = group.links
    normal = group.nodes.new("GeometryNodeInputNormal")
    blur = group.nodes.new("GeometryNodeBlurAttribute")
    blur.data_type = "FLOAT_VECTOR"
    links.new(normal.outputs[0], blur.inputs["Value"])
    links.new(group_input(group.nodes, {"Normal Smooth"}).outputs["Normal Smooth"], blur.inputs["Iterations"])
    return blend_normal(group, normal.outputs[0], blur.outputs[0], normal_weight)


def build_inflation_amount(group, controls, is_shell):
    """Balloon scales the profile, Shell moves a fixed distance."""
    nodes, links = group.nodes, group.links
    thickness = _math(
        group, "MULTIPLY", controls.outputs["Thickness"], BALLOON_THICKNESS_SCALE,
    )
    balloon = _math(
        group, "MULTIPLY", read_float_attribute(group, "o_balloon"), thickness,
    )
    amount = nodes.new("GeometryNodeSwitch")
    amount.input_type = "FLOAT"
    links.new(is_shell, amount.inputs["Switch"])
    links.new(balloon, amount.inputs["False"])
    links.new(controls.outputs["Shell Thickness"], amount.inputs["True"])
    return amount.outputs[0]


def build_solid(group, surface, amount, normal, is_shell, controls, weld_distance):
    """Inflate the projected surface into a front leaf, wall and rear leaf."""
    nodes, links = group.nodes, group.links

    def offset(distance):
        result = nodes.new("ShaderNodeVectorMath")
        result.operation = "SCALE"
        links.new(normal, result.inputs[0])
        links.new(distance, result.inputs[3])
        return result.outputs[0]

    inflation = _math(
        group, "MULTIPLY", amount,
        _math(group, "MULTIPLY", controls.outputs["Front Inflation"], FRONT_INFLATION_SCALE),
    )
    front_amount = nodes.new("GeometryNodeSwitch")
    front_amount.input_type = "FLOAT"
    links.new(is_shell, front_amount.inputs["Switch"])
    links.new(inflation, front_amount.inputs["False"])
    front_amount.inputs["True"].default_value = 0.0

    front = nodes.new("GeometryNodeSetPosition")
    links.new(surface, front.inputs["Geometry"])
    links.new(offset(front_amount.outputs[0]), front.inputs["Offset"])

    span = _math(group, "ADD", amount, front_amount.outputs[0])
    span = _math(group, "MULTIPLY", span, -1.0)
    extrude = nodes.new("GeometryNodeExtrudeMesh")
    extrude.mode = "FACES"
    extrude.inputs["Individual"].default_value = False
    links.new(front.outputs["Geometry"], extrude.inputs["Mesh"])
    links.new(offset(span), extrude.inputs["Offset"])

    # Extruding against the normal leaves the rear leaf and wall facing inward.
    flipped = nodes.new("GeometryNodeFlipFaces")
    links.new(extrude.outputs["Mesh"], flipped.inputs["Mesh"])
    rear = store_float_attribute(
        group, flipped.outputs["Mesh"], NORMAL_REDUCTION_ATTRIBUTE_NAME, 1.0,
    )
    join = nodes.new("GeometryNodeJoinGeometry")
    links.new(front.outputs["Geometry"], join.inputs["Geometry"])
    links.new(rear, join.inputs["Geometry"])
    merge = nodes.new("GeometryNodeMergeByDistance")
    merge.mode = "ALL"
    links.new(weld_distance, merge.inputs["Distance"])
    links.new(join.outputs["Geometry"], merge.inputs["Geometry"])
    return merge.outputs["Geometry"]


def _build_depth_surface(group, geometry, controls):
    """Project the depth image and inflate the projected surface into a solid."""
    links = group.links
    split = controls.outputs["Depth Split"]
    image = controls.outputs["Depth Image"]
    scale = controls.outputs["Uniform Scale"]
    original = geometry
    geometry, corner_camera, cut_vertex = split_depth_surface(
        group, geometry, sample_face_camera(group, image), split, controls.outputs["Reference Depth"],
        controls.outputs["Depth Scale"], triangles=True,
    )
    geometry = remove_boundary_triangles(group, geometry)
    boundary = edge_boundary_field(group.nodes, group.links)
    rim = evaluate_field(group, boundary, "FLOAT", "POINT")
    camera = build_surface_camera(
        group, _position_field(group, image), corner_camera, cut_vertex, split,
    )
    projection = project_depth_surface(
        group, geometry, camera, scale, controls.outputs["Reference Depth"], controls.outputs["Depth Scale"],
    )
    projection = smooth_cut_boundary(group, projection, cut_vertex, boundary=rim)
    # Clamped depth pixels can collapse adjacent outline samples after projection.
    edge = group.nodes.new("GeometryNodeInputMeshEdgeVertices")
    length = group.nodes.new("ShaderNodeVectorMath")
    length.operation = "DISTANCE"
    links.new(edge.outputs["Position 1"], length.inputs[0])
    links.new(edge.outputs["Position 2"], length.inputs[1])
    typical = group.nodes.new("GeometryNodeAttributeStatistic")
    typical.data_type, typical.domain = "FLOAT", "EDGE"
    links.new(projection, typical.inputs["Geometry"])
    links.new(length.outputs["Value"], typical.inputs["Attribute"])
    merge = group.nodes.new("GeometryNodeMergeByDistance")
    merge.mode = "CONNECTED"
    links.new(projection, merge.inputs["Geometry"])
    links.new(_math(group, "MULTIPLY", typical.outputs["Mean"], 1e-6), merge.inputs["Distance"])
    projection = merge.outputs["Geometry"]
    projection = taper_split_profile(group, projection, original_boundary_field(group, original, rim))
    # The mode field is shared by the geometry and thickness choices.
    mode = group.nodes.new("GeometryNodeMenuSwitch")
    mode.data_type = "BOOLEAN"
    for item, name in zip(mode.enum_items, ("Balloon", "Shell")):
        item.name = name
    links.new(controls.outputs["Mode"], mode.inputs["Menu"])
    mode.inputs["Balloon"].default_value = False
    mode.inputs["Shell"].default_value = True
    is_shell = mode.outputs[0]
    amount = build_inflation_amount(group, controls, is_shell)
    statistics = group.nodes.new("GeometryNodeAttributeStatistic")
    statistics.data_type, statistics.domain = "FLOAT", "POINT"
    links.new(projection, statistics.inputs["Geometry"])
    links.new(amount, statistics.inputs["Attribute"])
    has_thickness = compare_node(group, "GREATER_THAN", statistics.outputs["Max"], 1e-6)
    zero_shell = group.nodes.new("GeometryNodeSwitch")
    zero_shell.input_type = "GEOMETRY"
    links.new(has_thickness, zero_shell.inputs["Switch"])
    links.new(projection, zero_shell.inputs["False"])
    normal = build_front_normal(group, build_normal_weight(group, is_shell))
    # Both leaves must inflate along one normal, so it is carried across the
    # extrusion instead of being evaluated again on the moved surface.
    projection = store_vector_attribute(
        group, projection, SOLID_NORMAL_ATTRIBUTE, normal,
    )
    solid = build_solid(
        group, projection, amount, read_vector_attribute(group, SOLID_NORMAL_ATTRIBUTE),
        is_shell, controls,
        _math(group, "MULTIPLY", typical.outputs["Mean"], 1e-3),
    )
    links.new(solid, zero_shell.inputs["True"])
    return remove_attribute_pattern(group, zero_shell.outputs[0], "_o_*")


def build_image_depth_cutout_group():
    name = NODE_GROUP_NAME
    existing = bpy.data.node_groups.get(name)
    if existing is not None:
        return existing
    group = bpy.data.node_groups.new(name, 'GeometryNodeTree')
    group.is_modifier, group.use_fake_user = (True, True)
    group.color_tag = 'GEOMETRY'
    interface_socket(group, 'Geometry', 'INPUT', 'NodeSocketGeometry')
    interface_socket(group, 'Mode', 'INPUT', 'NodeSocketMenu')
    float_input(group, 'Thickness', 0.0, maximum=2.0).description = 'Control how much the surface bulges in Balloon mode. Zero removes the bulge.'
    float_input(group, 'Shell Thickness', 0.0, maximum=1.0, subtype='DISTANCE').description = 'Add thickness behind the original surface while keeping the front surface in place.'
    float_input(group, 'Depth Scale', 1.0, maximum=2.0)
    float_input(group, 'Depth Split', 0.1, maximum=1, subtype='FACTOR').description = 'Split the mesh where depth changes abruptly. Scaled by Depth Scale: a flat projection stays whole, higher values detect smaller depth jumps.'
    options = group.interface.new_panel(name='Options', default_closed=True)
    boundary_smooth = interface_socket(group, 'Boundary Smooth', 'INPUT', 'NodeSocketInt', options)
    boundary_smooth.default_value, boundary_smooth.min_value, boundary_smooth.max_value = 4, 0, 16
    boundary_smooth.description = 'Smooth geometry near the original outline and Depth Split edges. Zero disables boundary smoothing.'
    normal_smooth = interface_socket(group, 'Normal Smooth', 'INPUT', 'NodeSocketInt', options)
    normal_smooth.default_value, normal_smooth.min_value, normal_smooth.max_value = 512, 16, 512
    normal_smooth.description = 'Control smoothing of front and rear displacement normals. Higher values produce smoother directions.'
    float_input(group, 'Front Inflation', 0.2, maximum=1, subtype='FACTOR', parent=options).description = 'Control how much the front surface bulges in Balloon mode, reaching half of the balloon thickness. Zero keeps the original front surface.'
    float_input(group, 'Reference Depth', 1.0, subtype='DISTANCE', parent=options)
    data = group.interface.new_panel(name='Data', default_closed=True)
    float_input(group, 'Uniform Scale', 1.0, parent=data).hide_in_modifier = True
    interface_socket(group, 'Depth Image', 'INPUT', 'NodeSocketImage', data).hide_in_modifier = True
    interface_socket(group, 'Geometry', 'OUTPUT', 'NodeSocketGeometry')
    controls = group_input(group.nodes, set())
    geometry = store_float_attribute(group, controls.outputs['Geometry'], NORMAL_REDUCTION_ATTRIBUTE_NAME, 0.0)
    geometry = _build_depth_surface(group, geometry, controls)
    _shade_output(group, geometry)
    prepare_node_group(group)
    for item in group.interface.items_tree:
        if item.item_type != 'SOCKET' or item.in_out != 'INPUT':
            continue
        if item.name == 'Mode':
            item.default_value = 'Balloon'
        elif item.name == 'Shell Thickness':
            item.name = 'Thickness'
    return group