from dataclasses import dataclass
from functools import partial
import struct

@dataclass
class IspTspInstructionWordMV:
    volume_instruction: int
    culling_mode: int

    def __init__(self, value):
        assert (value & 0x7ffffff) == 0
        self.volume_instruction = (value >> 29) & 0b111
        self.culling_mode = (value >> 27) & 0b11

@dataclass
class IspTspInstructionWord:
    depth_compare_mode: int
    culling_mode: int
    z_write_disable: int
    texture: int
    offset: int
    gouraud_shading: int
    _16bit_uv: int
    cache_bypass: int
    dcalc_ctrl: int

    def __init__(self, value):
        assert (value & 0xfffff) == 0, (value, hex(value))
        self.depth_compare_mode = (value >> 29) & 0b111
        self.culling_mode = (value >> 27) & 0b11
        self.z_write_disable = (value >> 26) & 1
        self.texture = (value >> 25) & 1
        self.offset = (value >> 24) & 1
        self.gouraud_shading = (value >> 23) & 1
        self._16bit_uv = (value >> 22) & 1
        self.cache_bypass = (value >> 21) & 1
        self.dcalc_ctrl = (value >> 20) & 1

@dataclass
class TspInstructionWord:
    src_alpha_instr: int
    dst_alpha_instr: int
    src_select: int
    dst_select: int
    fog_control: int
    color_clamp: int
    use_alpha: int
    ignore_texture_alpha: int
    flip_uv: int
    clamp_uv: int
    filter_mode: int
    super_sample_texture: int
    mip_map_d_adjust: int
    texture_shading_instruction: int
    texture_u_size: int
    texture_v_size: int

    def __init__(self, value):
        self.src_alpha_instr = (value >> 29) & 0b111
        self.dst_alpha_instr = (value >> 26) & 0b111
        self.src_select = (value >> 25) & 1
        self.dst_select = (value >> 24) & 1
        self.fog_control = (value >> 22) & 0b11
        self.color_clamp = (value >> 21) & 1
        self.use_alpha = (value >> 20) & 1
        self.ignore_texture_alpha = (value >> 19) & 1
        self.flip_uv = (value >> 17) & 0b11
        self.clamp_uv = (value >> 15) & 0b11
        self.filter_mode = (value >> 13) & 0b11
        self.super_sample_texture = (value >> 12) & 1
        self.mip_map_d_adjust = (value >> 8) & 0b1111
        self.texture_shading_instruction = (value >> 6) & 0b11
        self.texture_u_size = (value >> 3) & 0b111
        self.texture_v_size = (value >> 0) & 0b111

@dataclass
class TextureControlWord:
    mip_mapped: int
    vq_compressed: int
    pixel_format: int
    scan_order: int
    stride_select: int
    texture_address: int

    def __init__(self, value):
        assert (value >> 21) & 0b1111 == 0

        self.mip_mapped = (value >> 31) & 1
        self.vq_compressed = (value >> 30) & 1
        self.pixel_format = (value >> 27) & 0b111
        self.scan_order = (value >> 26) & 1
        self.stride_select = (value >> 25) & 1
        self.texture_address = ((value >> 0) & 0x1fffff) * 8

@dataclass
class Vertex:
    x: float
    y: float
    z: float
    attributes: list

@dataclass
class ISPTSPParameter:
    isp_tsp_instruction_word: IspTspInstructionWord
    tsp_instruction_word: TspInstructionWord
    texture_control_word: TextureControlWord
    vertices: list[Vertex]

@dataclass
class ISPTSPParameterMV:
    isp_tsp_instruction_word: IspTspInstructionWord
    vertices: list[Vertex]

def expected_skip_size(isp_tsp):
    pass

def parse_parameter(mem, offset, skip, shadow, tag_offset, vertex_count, modifier_volume):
    assert skip >= 0, skip
    assert shadow in {True, False}
    if shadow:
        skip = (skip * 2 + 3)
    else:
        skip = (skip + 3) # size of one vertex

    params = []

    def unpack(i, t):
        i_offset = offset + i * 4
        #print("I_OFFSET:", i_offset)
        value, = struct.unpack("<" + t, mem[i_offset:i_offset + 4])
        return value

    unpack_int = partial(unpack, t="I")
    unpack_float = partial(unpack, t="f")

    if modifier_volume:
        assert skip == 3, skip
        parameter = ISPTSPParameterMV(
            IspTspInstructionWordMV(unpack_int(0)),
            vertices=[]
        )
        value1 = unpack_int(1)
        assert value1 == 0, value1
        value2 = unpack_int(2)
        assert value2 == 0, value2
    else:
        parameter = ISPTSPParameter(
            IspTspInstructionWord(unpack_int(0)),
            TspInstructionWord(unpack_int(1)),
            TextureControlWord(unpack_int(2)),
            vertices=[]
        )


    assert tag_offset == 0, tag_offset # FIXME

    i = 3
    for _ in range(vertex_count):
        vertex = Vertex(
            x = unpack_float(i + 0),
            y = unpack_float(i + 1),
            z = unpack_float(i + 2),
            attributes=[]
        )

        j = 3
        while j < skip:
            vertex.attributes.append(unpack_int(i + j))
            j += 1

        parameter.vertices.append(vertex)

        i += skip

    return offset + i * 4, parameter