#!/usr/bin/python
# Copyright 2017 The ANGLE Project Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
#
# gen_uniform_type_table.py:
#  Code generation for OpenGL uniform type info tables.
#  NOTE: don't run this script directly. Run scripts/run_code_generation.py.

from datetime import date

import sys

all_uniform_types = [
    "GL_NONE", "GL_BOOL", "GL_BOOL_VEC2", "GL_BOOL_VEC3", "GL_BOOL_VEC4", "GL_FLOAT",
    "GL_FLOAT_MAT2", "GL_FLOAT_MAT2x3", "GL_FLOAT_MAT2x4", "GL_FLOAT_MAT3", "GL_FLOAT_MAT3x2",
    "GL_FLOAT_MAT3x4", "GL_FLOAT_MAT4", "GL_FLOAT_MAT4x2", "GL_FLOAT_MAT4x3", "GL_FLOAT_VEC2",
    "GL_FLOAT_VEC3", "GL_FLOAT_VEC4", "GL_IMAGE_2D", "GL_IMAGE_2D_ARRAY", "GL_IMAGE_3D",
    "GL_IMAGE_CUBE", "GL_INT", "GL_INT_IMAGE_2D", "GL_INT_IMAGE_2D_ARRAY", "GL_INT_IMAGE_3D",
    "GL_INT_IMAGE_CUBE", "GL_INT_SAMPLER_2D", "GL_INT_SAMPLER_2D_ARRAY",
    "GL_INT_SAMPLER_2D_MULTISAMPLE", "GL_INT_SAMPLER_2D_MULTISAMPLE_ARRAY", "GL_INT_SAMPLER_3D",
    "GL_INT_SAMPLER_CUBE", "GL_INT_VEC2", "GL_INT_VEC3", "GL_INT_VEC4", "GL_SAMPLER_2D",
    "GL_SAMPLER_2D_ARRAY", "GL_SAMPLER_2D_ARRAY_SHADOW", "GL_SAMPLER_2D_MULTISAMPLE",
    "GL_SAMPLER_2D_MULTISAMPLE_ARRAY", "GL_SAMPLER_2D_RECT_ANGLE", "GL_SAMPLER_2D_SHADOW",
    "GL_SAMPLER_3D", "GL_SAMPLER_CUBE", "GL_SAMPLER_CUBE_SHADOW", "GL_SAMPLER_EXTERNAL_OES",
    "GL_UNSIGNED_INT", "GL_UNSIGNED_INT_ATOMIC_COUNTER", "GL_UNSIGNED_INT_IMAGE_2D",
    "GL_UNSIGNED_INT_IMAGE_2D_ARRAY", "GL_UNSIGNED_INT_IMAGE_3D", "GL_UNSIGNED_INT_IMAGE_CUBE",
    "GL_UNSIGNED_INT_SAMPLER_2D", "GL_UNSIGNED_INT_SAMPLER_2D_ARRAY",
    "GL_UNSIGNED_INT_SAMPLER_2D_MULTISAMPLE", "GL_UNSIGNED_INT_SAMPLER_2D_MULTISAMPLE_ARRAY",
    "GL_UNSIGNED_INT_SAMPLER_3D", "GL_UNSIGNED_INT_SAMPLER_CUBE", "GL_UNSIGNED_INT_VEC2",
    "GL_UNSIGNED_INT_VEC3", "GL_UNSIGNED_INT_VEC4", "GL_SAMPLER_VIDEO_IMAGE_WEBGL"
]

# Uniform texture types. Be wary of substrings finding the wrong types.
# e.g. with 2D_MULTISAMPLE/2D_ARRAY and 2D.
texture_types = {
    "2D": "2D",
    "2D_ARRAY": "2D_ARRAY",
    "2D_ARRAY_SHADOW": "2D_ARRAY",
    "2D_MULTISAMPLE": "2D_MULTISAMPLE",
    "2D_MULTISAMPLE_ARRAY": "2D_MULTISAMPLE_ARRAY",
    "2D_RECT_ANGLE": "2D",
    "2D_SHADOW": "2D",
    "3D": "3D",
    "CUBE": "CUBE_MAP",
    "CUBE_SHADOW": "CUBE_MAP",
    "EXTERNAL_OES": "EXTERNAL_OES",
    "RECT": "RECTANGLE",
    "VIDEO_IMAGE_WEBGL": "VIDEO_IMAGE_WEBGL",
}

template_cpp = """// GENERATED FILE - DO NOT EDIT.
// Generated by {script_name}.
//
// Copyright {copyright_year} The ANGLE Project Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//
// Uniform type info table:
//   Metadata about a particular uniform format, indexed by GL type.

#include <array>
#include "common/utilities.h"

using namespace angle;

namespace gl
{{

namespace
{{
constexpr std::array<UniformTypeInfo, {total_count}> kInfoTable =
{{{{
{uniform_type_info_data}
}}}};

size_t GetTypeInfoIndex(GLenum uniformType)
{{
    switch (uniformType)
    {{
{uniform_type_index_cases}
        default:
            UNREACHABLE();
            return 0;
    }}
}}
}}  // anonymous namespace

const UniformTypeInfo &GetUniformTypeInfo(GLenum uniformType)
{{
    ASSERT(kInfoTable[GetTypeInfoIndex(uniformType)].type == uniformType);
    return kInfoTable[GetTypeInfoIndex(uniformType)];
}}

}}  // namespace gl
"""

type_info_data_template = """{{{type}, {component_type}, {texture_type}, {transposed_type}, {bool_type}, {sampler_format}, {rows}, {columns}, {components}, {component_size}, {internal_size}, {external_size}, {is_sampler}, {is_matrix}, {is_image}, {glsl_asfloat} }}"""
type_index_case_template = """case {enum_value}: return {index_value};"""


def cpp_bool(value):
    return "true" if value else "false"


def get_component_type(uniform_type):
    if uniform_type.find("GL_BOOL") == 0:
        return "GL_BOOL"
    elif uniform_type.find("GL_FLOAT") == 0:
        return "GL_FLOAT"
    elif uniform_type.find("GL_INT") == 0:
        return "GL_INT"
    elif uniform_type.find("GL_UNSIGNED_INT") == 0:
        return "GL_UNSIGNED_INT"
    elif uniform_type == "GL_NONE":
        return "GL_NONE"
    else:
        return "GL_INT"


def get_texture_type(uniform_type):
    for sampler_type, tex_type in texture_types.items():
        if uniform_type.endswith(sampler_type):
            return "GL_TEXTURE_" + tex_type
    return "GL_NONE"


def get_transposed_type(uniform_type):
    if "_MAT" in uniform_type:
        if "x" in uniform_type:
            return "GL_FLOAT_MAT" + uniform_type[-1] + "x" + uniform_type[uniform_type.find("_MAT")
                                                                          + 4]
        else:
            return uniform_type
    else:
        return "GL_NONE"


def get_bool_type(uniform_type):
    if uniform_type == "GL_INT" or uniform_type == "GL_UNSIGNED_INT" or uniform_type == "GL_FLOAT":
        return "GL_BOOL"
    elif "_VEC" in uniform_type:
        return "GL_BOOL_VEC" + uniform_type[-1]
    else:
        return "GL_NONE"


def get_sampler_format(uniform_type):
    if not "_SAMPLER_" in uniform_type:
        return "SamplerFormat::InvalidEnum"
    elif "_SHADOW" in uniform_type:
        return "SamplerFormat::Shadow"
    elif "GL_UNSIGNED_INT_SAMPLER_" in uniform_type:
        return "SamplerFormat::Unsigned"
    elif "GL_INT_SAMPLER_" in uniform_type:
        return "SamplerFormat::Signed"
    else:
        return "SamplerFormat::Float"


def get_rows(uniform_type):
    if uniform_type == "GL_NONE":
        return "0"
    elif "_MAT" in uniform_type:
        return uniform_type[-1]
    else:
        return "1"


def get_columns(uniform_type):
    if uniform_type == "GL_NONE":
        return "0"
    elif "_VEC" in uniform_type:
        return uniform_type[-1]
    elif "_MAT" in uniform_type:
        return uniform_type[uniform_type.find("_MAT") + 4]
    else:
        return "1"


def get_components(uniform_type):
    return str(int(get_rows(uniform_type)) * int(get_columns(uniform_type)))


def get_component_size(uniform_type):
    component_type = get_component_type(uniform_type)
    if component_type == "GL_BOOL":
        return "sizeof(GLint)"
    elif component_type == "GL_FLOAT":
        return "sizeof(GLfloat)"
    elif component_type == "GL_INT":
        return "sizeof(GLint)"
    elif component_type == "GL_UNSIGNED_INT":
        return "sizeof(GLuint)"
    elif component_type == "GL_NONE":
        return "0"
    else:
        raise "Invalid component type: " + component_type


def get_internal_size(uniform_type):
    return get_component_size(uniform_type) + " * " + str(int(get_rows(uniform_type)) * 4)


def get_external_size(uniform_type):
    return get_component_size(uniform_type) + " * " + get_components(uniform_type)


def get_is_sampler(uniform_type):
    return cpp_bool("_SAMPLER_" in uniform_type)


def get_is_matrix(uniform_type):
    return cpp_bool("_MAT" in uniform_type)


def get_is_image(uniform_type):
    return cpp_bool("_VIDEO_" not in uniform_type and "_IMAGE_" in uniform_type)


def get_glsl_asfloat(uniform_type):
    component_type = get_component_type(uniform_type)
    if component_type == "GL_BOOL":
        return '""'
    elif component_type == "GL_FLOAT":
        return '""'
    elif component_type == "GL_INT":
        return '"intBitsToFloat"'
    elif component_type == "GL_UNSIGNED_INT":
        return '"uintBitsToFloat"'
    elif component_type == "GL_NONE":
        return '""'
    else:
        raise "Invalid component type: " + component_type


def gen_type_info(uniform_type):
    return type_info_data_template.format(
        type=uniform_type,
        component_type=get_component_type(uniform_type),
        texture_type=get_texture_type(uniform_type),
        transposed_type=get_transposed_type(uniform_type),
        bool_type=get_bool_type(uniform_type),
        sampler_format=get_sampler_format(uniform_type),
        rows=get_rows(uniform_type),
        columns=get_columns(uniform_type),
        components=get_components(uniform_type),
        component_size=get_component_size(uniform_type),
        internal_size=get_internal_size(uniform_type),
        external_size=get_external_size(uniform_type),
        is_sampler=get_is_sampler(uniform_type),
        is_matrix=get_is_matrix(uniform_type),
        is_image=get_is_image(uniform_type),
        glsl_asfloat=get_glsl_asfloat(uniform_type))


def gen_type_index_case(index, uniform_type):
    return "case " + uniform_type + ": return " + str(index) + ";"


def main():

    # auto_script parameters.
    if len(sys.argv) > 1:
        inputs = []
        outputs = ['uniform_type_info_autogen.cpp']

        if sys.argv[1] == 'inputs':
            print ','.join(inputs)
        elif sys.argv[1] == 'outputs':
            print ','.join(outputs)
        else:
            print('Invalid script parameters')
            return 1
        return 0

    uniform_type_info_data = ",\n".join(
        [gen_type_info(uniform_type) for uniform_type in all_uniform_types])
    uniform_type_index_cases = "\n".join([
        gen_type_index_case(index, uniform_type)
        for index, uniform_type in enumerate(all_uniform_types)
    ])

    with open('uniform_type_info_autogen.cpp', 'wt') as out_file:
        output_cpp = template_cpp.format(
            script_name=sys.argv[0],
            copyright_year=date.today().year,
            total_count=len(all_uniform_types),
            uniform_type_info_data=uniform_type_info_data,
            uniform_type_index_cases=uniform_type_index_cases)
        out_file.write(output_cpp)
        out_file.close()
    return 0


if __name__ == '__main__':
    sys.exit(main())
