#include "assets/ppi_header.h"
#include "test_harness.h"

#include <array>
#include <bit>
#include <cstddef>
#include <cstdint>
#include <string_view>
#include <vector>

using pp::assets::parse_ppi_header;
using pp::assets::create_minimal_ppi_project;
using pp::assets::decode_ppi_project_images;
using pp::assets::parse_ppi_project_index;
using pp::assets::parse_ppi_project_summary;
using pp::assets::parse_ppi_project_layout;
using pp::assets::ppi_header_size;
using pp::assets::ppi_thumbnail_byte_size;
using pp::foundation::StatusCode;

namespace {

void append_u32(std::vector<std::byte>& bytes, std::uint32_t value)
{
    bytes.push_back(static_cast<std::byte>(value & 0xffU));
    bytes.push_back(static_cast<std::byte>((value >> 8U) & 0xffU));
    bytes.push_back(static_cast<std::byte>((value >> 16U) & 0xffU));
    bytes.push_back(static_cast<std::byte>((value >> 24U) & 0xffU));
}

void append_u32_be(std::vector<std::byte>& bytes, std::uint32_t value)
{
    bytes.push_back(static_cast<std::byte>((value >> 24U) & 0xffU));
    bytes.push_back(static_cast<std::byte>((value >> 16U) & 0xffU));
    bytes.push_back(static_cast<std::byte>((value >> 8U) & 0xffU));
    bytes.push_back(static_cast<std::byte>(value & 0xffU));
}

void append_f32(std::vector<std::byte>& bytes, float value)
{
    append_u32(bytes, std::bit_cast<std::uint32_t>(value));
}

void append_ascii(std::vector<std::byte>& bytes, std::string_view value)
{
    for (const auto ch : value) {
        bytes.push_back(static_cast<std::byte>(ch));
    }
}

std::vector<std::byte> valid_header()
{
    std::vector<std::byte> bytes {
        std::byte { 'P' },
        std::byte { 'P' },
        std::byte { 'I' },
        std::byte { 0 },
    };
    append_u32(bytes, 0);
    append_u32(bytes, 4);
    append_u32(bytes, 0);
    append_u32(bytes, 2);
    append_u32(bytes, 3);
    append_u32(bytes, 1024);
    append_u32(bytes, 128);
    append_u32(bytes, 128);
    append_u32(bytes, 4);
    return bytes;
}

void append_minimal_body(std::vector<std::byte>& bytes)
{
    append_u32(bytes, 64);
    append_u32(bytes, 32);
    append_u32(bytes, 1);
    append_u32(bytes, 1);
    append_u32(bytes, 0);
    append_f32(bytes, 1.0F);
    append_u32(bytes, 3);
    append_ascii(bytes, "Ink");
    append_u32(bytes, 0);
    bytes.push_back(std::byte { 0 });
    bytes.push_back(std::byte { 1 });
    append_u32(bytes, 1);
    append_u32(bytes, 100);
    for (std::uint32_t i = 0; i < 6U; ++i) {
        append_u32(bytes, 0);
    }
    append_u32(bytes, 0);
}

std::vector<std::byte> png_ihdr_payload(
    std::uint32_t width,
    std::uint32_t height,
    std::uint8_t bit_depth = 8U,
    std::uint8_t color_type = 6U)
{
    std::vector<std::byte> bytes {
        std::byte { 0x89 },
        std::byte { 0x50 },
        std::byte { 0x4e },
        std::byte { 0x47 },
        std::byte { 0x0d },
        std::byte { 0x0a },
        std::byte { 0x1a },
        std::byte { 0x0a },
    };
    append_u32_be(bytes, 13);
    bytes.push_back(std::byte { 'I' });
    bytes.push_back(std::byte { 'H' });
    bytes.push_back(std::byte { 'D' });
    bytes.push_back(std::byte { 'R' });
    append_u32_be(bytes, width);
    append_u32_be(bytes, height);
    bytes.push_back(static_cast<std::byte>(bit_depth));
    bytes.push_back(static_cast<std::byte>(color_type));
    bytes.push_back(std::byte { 0 });
    bytes.push_back(std::byte { 0 });
    bytes.push_back(std::byte { 0 });
    append_u32_be(bytes, 0);
    return bytes;
}

std::vector<std::byte> transparent_png_1x1()
{
    return {
        std::byte { 0x89 }, std::byte { 0x50 }, std::byte { 0x4e }, std::byte { 0x47 },
        std::byte { 0x0d }, std::byte { 0x0a }, std::byte { 0x1a }, std::byte { 0x0a },
        std::byte { 0x00 }, std::byte { 0x00 }, std::byte { 0x00 }, std::byte { 0x0d },
        std::byte { 0x49 }, std::byte { 0x48 }, std::byte { 0x44 }, std::byte { 0x52 },
        std::byte { 0x00 }, std::byte { 0x00 }, std::byte { 0x00 }, std::byte { 0x01 },
        std::byte { 0x00 }, std::byte { 0x00 }, std::byte { 0x00 }, std::byte { 0x01 },
        std::byte { 0x08 }, std::byte { 0x06 }, std::byte { 0x00 }, std::byte { 0x00 },
        std::byte { 0x00 }, std::byte { 0x1f }, std::byte { 0x15 }, std::byte { 0xc4 },
        std::byte { 0x89 }, std::byte { 0x00 }, std::byte { 0x00 }, std::byte { 0x00 },
        std::byte { 0x0b }, std::byte { 0x49 }, std::byte { 0x44 }, std::byte { 0x41 },
        std::byte { 0x54 }, std::byte { 0x78 }, std::byte { 0x9c }, std::byte { 0x63 },
        std::byte { 0x60 }, std::byte { 0x00 }, std::byte { 0x02 }, std::byte { 0x00 },
        std::byte { 0x00 }, std::byte { 0x05 }, std::byte { 0x00 }, std::byte { 0x01 },
        std::byte { 0x7a }, std::byte { 0x5e }, std::byte { 0xab }, std::byte { 0x3f },
        std::byte { 0x00 }, std::byte { 0x00 }, std::byte { 0x00 }, std::byte { 0x00 },
        std::byte { 0x49 }, std::byte { 0x45 }, std::byte { 0x4e }, std::byte { 0x44 },
        std::byte { 0xae }, std::byte { 0x42 }, std::byte { 0x60 }, std::byte { 0x82 },
    };
}

std::vector<std::byte> minimal_project()
{
    auto bytes = valid_header();
    bytes.resize(ppi_header_size + (128U * 128U * 4U), std::byte { 0 });
    append_minimal_body(bytes);
    return bytes;
}

std::vector<std::byte> project_with_single_face_payload(
    std::vector<std::byte> payload,
    std::uint32_t dirty_width = 8,
    std::uint32_t dirty_height = 4)
{
    auto bytes = valid_header();
    bytes.resize(ppi_header_size + (128U * 128U * 4U), std::byte { 0 });

    append_u32(bytes, 64);
    append_u32(bytes, 32);
    append_u32(bytes, 1);
    append_u32(bytes, 1);
    append_u32(bytes, 0);
    append_f32(bytes, 1.0F);
    append_u32(bytes, 3);
    append_ascii(bytes, "Ink");
    append_u32(bytes, 0);
    bytes.push_back(std::byte { 0 });
    bytes.push_back(std::byte { 1 });
    append_u32(bytes, 1);
    append_u32(bytes, 100);

    append_u32(bytes, 1);
    append_u32(bytes, 2);
    append_u32(bytes, 3);
    append_u32(bytes, 2 + dirty_width);
    append_u32(bytes, 3 + dirty_height);
    append_u32(bytes, static_cast<std::uint32_t>(payload.size()));
    bytes.insert(bytes.end(), payload.begin(), payload.end());

    for (std::uint32_t i = 1; i < 6U; ++i) {
        append_u32(bytes, 0);
    }
    append_u32(bytes, 0);
    return bytes;
}

void parses_legacy_ppi_header(pp::tests::Harness& h)
{
    const auto bytes = valid_header();
    const auto header = parse_ppi_header(bytes);

    PP_EXPECT(h, bytes.size() == ppi_header_size);
    PP_EXPECT(h, header.ok());
    PP_EXPECT(h, header.value().document_version.major == 0U);
    PP_EXPECT(h, header.value().document_version.minor == 4U);
    PP_EXPECT(h, header.value().software_version.fix == 3U);
    PP_EXPECT(h, header.value().software_version.build == 1024U);
    PP_EXPECT(h, header.value().thumbnail.width == 128U);
    PP_EXPECT(h, header.value().thumbnail.height == 128U);
    PP_EXPECT(h, header.value().thumbnail.components == 4U);
}

void rejects_truncated_invalid_magic_and_bad_thumbnail(pp::tests::Harness& h)
{
    auto truncated = valid_header();
    truncated.pop_back();

    auto bad_magic = valid_header();
    bad_magic[0] = std::byte { 'X' };

    auto bad_thumb = valid_header();
    bad_thumb[32] = std::byte { 64 };

    const auto truncated_result = parse_ppi_header(truncated);
    const auto magic_result = parse_ppi_header(bad_magic);
    const auto thumb_result = parse_ppi_header(bad_thumb);

    PP_EXPECT(h, !truncated_result.ok());
    PP_EXPECT(h, truncated_result.status().code == StatusCode::out_of_range);
    PP_EXPECT(h, !magic_result.ok());
    PP_EXPECT(h, magic_result.status().code == StatusCode::invalid_argument);
    PP_EXPECT(h, !thumb_result.ok());
    PP_EXPECT(h, thumb_result.status().code == StatusCode::invalid_argument);
}

void rejects_unsupported_document_versions(pp::tests::Harness& h)
{
    auto bad_major = valid_header();
    bad_major[4] = std::byte { 1 };

    auto bad_minor = valid_header();
    bad_minor[8] = std::byte { 0 };

    const auto major_result = parse_ppi_header(bad_major);
    const auto minor_result = parse_ppi_header(bad_minor);

    PP_EXPECT(h, !major_result.ok());
    PP_EXPECT(h, major_result.status().code == StatusCode::invalid_argument);
    PP_EXPECT(h, !minor_result.ok());
    PP_EXPECT(h, minor_result.status().code == StatusCode::invalid_argument);
}

void parses_project_layout_with_thumbnail_and_body(pp::tests::Harness& h)
{
    const auto bytes = minimal_project();

    const auto layout = parse_ppi_project_layout(bytes);

    PP_EXPECT(h, layout.ok());
    PP_EXPECT(h, layout.value().thumbnail_offset == ppi_header_size);
    PP_EXPECT(h, layout.value().thumbnail_bytes == 128U * 128U * 4U);
    PP_EXPECT(h, layout.value().body_offset == ppi_header_size + (128U * 128U * 4U));
    PP_EXPECT(h, layout.value().body_bytes == 73U);
}

void rejects_project_layout_with_truncated_thumbnail(pp::tests::Harness& h)
{
    auto bytes = valid_header();
    bytes.resize(ppi_header_size + (128U * 128U * 4U) - 1U, std::byte { 0 });

    const auto layout = parse_ppi_project_layout(bytes);

    PP_EXPECT(h, !layout.ok());
    PP_EXPECT(h, layout.status().code == StatusCode::out_of_range);
}

void parses_minimal_project_body_summary(pp::tests::Harness& h)
{
    const auto project = minimal_project();
    const auto summary = parse_ppi_project_summary(project);

    PP_EXPECT(h, summary.ok());
    PP_EXPECT(h, summary.value().body.width == 64U);
    PP_EXPECT(h, summary.value().body.height == 32U);
    PP_EXPECT(h, summary.value().body.layer_count == 1U);
    PP_EXPECT(h, summary.value().body.declared_frame_count == 1U);
    PP_EXPECT(h, summary.value().body.total_layer_frames == 1U);
    PP_EXPECT(h, summary.value().body.dirty_face_count == 0U);
    PP_EXPECT(h, summary.value().body.rgba_face_payload_count == 0U);
    PP_EXPECT(h, summary.value().body.compressed_face_bytes == 0U);
    PP_EXPECT(h, summary.value().body.info_bytes == 0U);
}

void indexes_project_layers_frames_and_faces(pp::tests::Harness& h)
{
    const auto project = project_with_single_face_payload(png_ihdr_payload(8, 4));
    const auto index = parse_ppi_project_index(project);

    PP_EXPECT(h, index.ok());
    PP_EXPECT(h, index.value().body.layers.size() == 1U);
    PP_EXPECT(h, index.value().body.layers[0].stored_order == 0U);
    PP_EXPECT(h, index.value().body.layers[0].name == "Ink");
    PP_EXPECT(h, index.value().body.layers[0].visible);
    PP_EXPECT(h, index.value().body.layers[0].frames.size() == 1U);
    PP_EXPECT(h, index.value().body.layers[0].frames[0].duration_ms == 100U);
    PP_EXPECT(h, index.value().body.layers[0].frames[0].faces[0].has_data);
    PP_EXPECT(h, index.value().body.layers[0].frames[0].faces[0].x0 == 2U);
    PP_EXPECT(h, index.value().body.layers[0].frames[0].faces[0].x1 == 10U);
    PP_EXPECT(h, index.value().body.layers[0].frames[0].faces[0].payload_bytes == 33U);
    PP_EXPECT(h, index.value().body.layers[0].frames[0].faces[0].png_width == 8U);
    PP_EXPECT(h, !index.value().body.layers[0].frames[0].faces[1].has_data);
}

void validates_dirty_face_png_payload_metadata(pp::tests::Harness& h)
{
    const auto project = project_with_single_face_payload(png_ihdr_payload(8, 4));
    const auto summary = parse_ppi_project_summary(project);

    PP_EXPECT(h, summary.ok());
    PP_EXPECT(h, summary.value().body.dirty_face_count == 1U);
    PP_EXPECT(h, summary.value().body.rgba_face_payload_count == 1U);
    PP_EXPECT(h, summary.value().body.compressed_face_bytes == 33U);
}

void decodes_dirty_face_png_payloads(pp::tests::Harness& h)
{
    const auto project = project_with_single_face_payload(transparent_png_1x1(), 1, 1);
    const auto decoded = decode_ppi_project_images(project);

    PP_EXPECT(h, decoded.ok());
    PP_EXPECT(h, decoded.value().faces.size() == 1U);
    PP_EXPECT(h, decoded.value().faces[0].layer_index == 0U);
    PP_EXPECT(h, decoded.value().faces[0].frame_index == 0U);
    PP_EXPECT(h, decoded.value().faces[0].face_index == 0U);
    PP_EXPECT(h, decoded.value().faces[0].image.width == 1U);
    PP_EXPECT(h, decoded.value().faces[0].image.height == 1U);
    PP_EXPECT(h, decoded.value().faces[0].image.pixels.size() == 4U);
    PP_EXPECT(h, decoded.value().faces[0].image.pixels[3] == 0U);
}

void rejects_metadata_only_payload_when_decoding_pixels(pp::tests::Harness& h)
{
    const auto project = project_with_single_face_payload(png_ihdr_payload(8, 4));
    const auto decoded = decode_ppi_project_images(project);

    PP_EXPECT(h, !decoded.ok());
    PP_EXPECT(h, decoded.status().code == StatusCode::invalid_argument);
}

void rejects_invalid_dirty_face_png_payloads(pp::tests::Harness& h)
{
    auto mismatched_dimensions = project_with_single_face_payload(png_ihdr_payload(7, 4));
    auto non_rgba = project_with_single_face_payload(png_ihdr_payload(8, 4, 8, 2));
    auto bad_signature_payload = png_ihdr_payload(8, 4);
    bad_signature_payload[0] = std::byte { 0 };
    auto bad_signature = project_with_single_face_payload(bad_signature_payload);

    const auto mismatched_result = parse_ppi_project_summary(mismatched_dimensions);
    const auto non_rgba_result = parse_ppi_project_summary(non_rgba);
    const auto bad_signature_result = parse_ppi_project_summary(bad_signature);

    PP_EXPECT(h, !mismatched_result.ok());
    PP_EXPECT(h, mismatched_result.status().code == StatusCode::invalid_argument);
    PP_EXPECT(h, !non_rgba_result.ok());
    PP_EXPECT(h, non_rgba_result.status().code == StatusCode::invalid_argument);
    PP_EXPECT(h, !bad_signature_result.ok());
    PP_EXPECT(h, bad_signature_result.status().code == StatusCode::invalid_argument);
}

void rejects_invalid_project_body_summaries(pp::tests::Harness& h)
{
    auto truncated = minimal_project();
    truncated.pop_back();

    auto mismatched_frames = minimal_project();
    mismatched_frames[ppi_header_size + (128U * 128U * 4U) + 12U] = std::byte { 2 };

    auto bad_layer_name = minimal_project();
    bad_layer_name[ppi_header_size + (128U * 128U * 4U) + 24U] = std::byte { 255 };

    const auto truncated_result = parse_ppi_project_summary(truncated);
    const auto mismatched_frames_result = parse_ppi_project_summary(mismatched_frames);
    const auto bad_layer_name_result = parse_ppi_project_summary(bad_layer_name);

    PP_EXPECT(h, !truncated_result.ok());
    PP_EXPECT(h, truncated_result.status().code == StatusCode::out_of_range);
    PP_EXPECT(h, !mismatched_frames_result.ok());
    PP_EXPECT(h, mismatched_frames_result.status().code == StatusCode::invalid_argument);
    PP_EXPECT(h, !bad_layer_name_result.ok());
    PP_EXPECT(h, bad_layer_name_result.status().code == StatusCode::out_of_range);
}

void creates_minimal_project_for_roundtrip_load(pp::tests::Harness& h)
{
    const auto project = create_minimal_ppi_project(pp::assets::PpiMinimalProjectConfig {
        .width = 256,
        .height = 128,
        .layer_name = "Roundtrip",
        .frame_duration_ms = 333,
    });

    PP_EXPECT(h, project.ok());
    const auto index = parse_ppi_project_index(project.value());
    PP_EXPECT(h, index.ok());
    PP_EXPECT(h, index.value().layout.thumbnail_bytes == 128U * 128U * 4U);
    PP_EXPECT(h, index.value().body.summary.width == 256U);
    PP_EXPECT(h, index.value().body.summary.height == 128U);
    PP_EXPECT(h, index.value().body.summary.layer_count == 1U);
    PP_EXPECT(h, index.value().body.summary.declared_frame_count == 1U);
    PP_EXPECT(h, index.value().body.summary.dirty_face_count == 0U);
    PP_EXPECT(h, index.value().body.layers[0].name == "Roundtrip");
    PP_EXPECT(h, index.value().body.layers[0].opacity == 1.0F);
    PP_EXPECT(h, index.value().body.layers[0].visible);
    PP_EXPECT(h, index.value().body.layers[0].frames[0].duration_ms == 333U);
}

void rejects_invalid_minimal_project_writer_inputs(pp::tests::Harness& h)
{
    const auto no_size = create_minimal_ppi_project(pp::assets::PpiMinimalProjectConfig {
        .width = 0,
        .height = 128,
        .layer_name = "Ink",
        .frame_duration_ms = 100,
    });
    const auto no_name = create_minimal_ppi_project(pp::assets::PpiMinimalProjectConfig {
        .width = 128,
        .height = 128,
        .layer_name = "",
        .frame_duration_ms = 100,
    });
    const auto no_duration = create_minimal_ppi_project(pp::assets::PpiMinimalProjectConfig {
        .width = 128,
        .height = 128,
        .layer_name = "Ink",
        .frame_duration_ms = 0,
    });

    PP_EXPECT(h, !no_size.ok());
    PP_EXPECT(h, no_size.status().code == StatusCode::invalid_argument);
    PP_EXPECT(h, !no_name.ok());
    PP_EXPECT(h, no_name.status().code == StatusCode::invalid_argument);
    PP_EXPECT(h, !no_duration.ok());
    PP_EXPECT(h, no_duration.status().code == StatusCode::invalid_argument);
}

}

int main()
{
    pp::tests::Harness harness;
    harness.run("parses_legacy_ppi_header", parses_legacy_ppi_header);
    harness.run("rejects_truncated_invalid_magic_and_bad_thumbnail", rejects_truncated_invalid_magic_and_bad_thumbnail);
    harness.run("rejects_unsupported_document_versions", rejects_unsupported_document_versions);
    harness.run("parses_project_layout_with_thumbnail_and_body", parses_project_layout_with_thumbnail_and_body);
    harness.run("rejects_project_layout_with_truncated_thumbnail", rejects_project_layout_with_truncated_thumbnail);
    harness.run("parses_minimal_project_body_summary", parses_minimal_project_body_summary);
    harness.run("indexes_project_layers_frames_and_faces", indexes_project_layers_frames_and_faces);
    harness.run("validates_dirty_face_png_payload_metadata", validates_dirty_face_png_payload_metadata);
    harness.run("decodes_dirty_face_png_payloads", decodes_dirty_face_png_payloads);
    harness.run("rejects_metadata_only_payload_when_decoding_pixels", rejects_metadata_only_payload_when_decoding_pixels);
    harness.run("rejects_invalid_dirty_face_png_payloads", rejects_invalid_dirty_face_png_payloads);
    harness.run("rejects_invalid_project_body_summaries", rejects_invalid_project_body_summaries);
    harness.run("creates_minimal_project_for_roundtrip_load", creates_minimal_project_for_roundtrip_load);
    harness.run("rejects_invalid_minimal_project_writer_inputs", rejects_invalid_minimal_project_writer_inputs);
    return harness.finish();
}