#include "assets/image_format.h"
#include "document/document.h"
#include "foundation/parse.h"
#include "foundation/result.h"
#include "ui_core/layout_xml.h"

#include <cstdint>
#include <fstream>
#include <iostream>
#include <iterator>
#include <string>
#include <string_view>
#include <vector>

namespace {

struct DocumentArgs {
    std::uint32_t width = 0;
    std::uint32_t height = 0;
    std::uint32_t layers = 1;
};

struct InspectImageArgs {
    std::string path;
};

struct ParseLayoutArgs {
    std::string path;
};

void print_error(std::string_view command, std::string_view message)
{
    std::cout << "{\"ok\":false,\"command\":\"" << command
              << "\",\"error\":\"" << message << "\"}\n";
}

void print_help()
{
    std::cout
        << "pano_cli commands:\n"
        << "  create-document --width N --height N [--layers N]\n"
        << "  inspect-image --path FILE\n"
        << "  parse-layout --path FILE\n"
        << "  --help\n";
}

pp::foundation::Status parse_document_args(int argc, char** argv, DocumentArgs& args)
{
    for (int i = 2; i < argc; ++i) {
        const std::string_view key(argv[i]);
        if (key == "--width" || key == "--height" || key == "--layers") {
            if (i + 1 >= argc) {
                return pp::foundation::Status::invalid_argument("missing value for option");
            }

            const auto value = pp::foundation::parse_u32(argv[++i]);
            if (!value) {
                return value.status();
            }

            if (key == "--width") {
                args.width = value.value();
            } else if (key == "--height") {
                args.height = value.value();
            } else {
                args.layers = value.value();
            }
        } else {
            return pp::foundation::Status::invalid_argument("unknown option");
        }
    }

    if (args.width == 0 || args.height == 0) {
        return pp::foundation::Status::invalid_argument("width and height must be greater than zero");
    }

    if (args.layers == 0) {
        return pp::foundation::Status::invalid_argument("layer count must be greater than zero");
    }

    return pp::foundation::Status::success();
}

int create_document(int argc, char** argv)
{
    DocumentArgs args;
    const auto status = parse_document_args(argc, argv, args);
    if (!status.ok()) {
        print_error("create-document", status.message);
        return 2;
    }

    const auto document = pp::document::CanvasDocument::create(
        pp::document::DocumentConfig {
            .width = args.width,
            .height = args.height,
            .layer_count = args.layers,
        });
    if (!document) {
        print_error("create-document", document.status().message);
        return 2;
    }

    std::cout << "{\"ok\":true,\"command\":\"create-document\",\"document\":{"
              << "\"width\":" << document.value().width()
              << ",\"height\":" << document.value().height()
              << ",\"layers\":" << document.value().layers().size()
              << ",\"activeLayer\":" << document.value().active_layer_index()
              << ",\"frames\":" << document.value().frames().size()
              << ",\"activeFrame\":" << document.value().active_frame_index()
              << "}}\n";
    return 0;
}

pp::foundation::Status parse_inspect_image_args(int argc, char** argv, InspectImageArgs& args)
{
    for (int i = 2; i < argc; ++i) {
        const std::string_view key(argv[i]);
        if (key == "--path") {
            if (i + 1 >= argc) {
                return pp::foundation::Status::invalid_argument("missing value for option");
            }

            args.path = argv[++i];
        } else {
            return pp::foundation::Status::invalid_argument("unknown option");
        }
    }

    if (args.path.empty()) {
        return pp::foundation::Status::invalid_argument("path must not be empty");
    }

    return pp::foundation::Status::success();
}

int inspect_image(int argc, char** argv)
{
    InspectImageArgs args;
    const auto status = parse_inspect_image_args(argc, argv, args);
    if (!status.ok()) {
        print_error("inspect-image", status.message);
        return 2;
    }

    std::ifstream stream(args.path, std::ios::binary);
    if (!stream) {
        print_error("inspect-image", "image file could not be opened");
        return 2;
    }

    const std::vector<char> chars {
        std::istreambuf_iterator<char>(stream),
        std::istreambuf_iterator<char>()
    };
    const auto* data = reinterpret_cast<const std::byte*>(chars.data());
    const auto format = pp::assets::detect_image_format(std::span<const std::byte>(data, chars.size()));
    if (!format) {
        print_error("inspect-image", format.status().message);
        return 2;
    }

    std::cout << "{\"ok\":true,\"command\":\"inspect-image\",\"format\":\""
              << pp::assets::image_format_name(format.value())
              << "\",\"bytes\":" << chars.size() << "}\n";
    return 0;
}

pp::foundation::Status parse_layout_args(int argc, char** argv, ParseLayoutArgs& args)
{
    for (int i = 2; i < argc; ++i) {
        const std::string_view key(argv[i]);
        if (key == "--path") {
            if (i + 1 >= argc) {
                return pp::foundation::Status::invalid_argument("missing value for option");
            }

            args.path = argv[++i];
        } else {
            return pp::foundation::Status::invalid_argument("unknown option");
        }
    }

    if (args.path.empty()) {
        return pp::foundation::Status::invalid_argument("path must not be empty");
    }

    return pp::foundation::Status::success();
}

int parse_layout(int argc, char** argv)
{
    ParseLayoutArgs args;
    const auto status = parse_layout_args(argc, argv, args);
    if (!status.ok()) {
        print_error("parse-layout", status.message);
        return 2;
    }

    std::ifstream stream(args.path, std::ios::binary);
    if (!stream) {
        print_error("parse-layout", "layout file could not be opened");
        return 2;
    }

    const std::string xml {
        std::istreambuf_iterator<char>(stream),
        std::istreambuf_iterator<char>()
    };
    const auto summary = pp::ui::parse_layout_xml(xml);
    if (!summary) {
        print_error("parse-layout", summary.status().message);
        return 2;
    }

    std::cout << "{\"ok\":true,\"command\":\"parse-layout\""
              << ",\"nodes\":" << summary.value().node_count
              << ",\"lengthAttributes\":" << summary.value().length_attribute_count
              << "}\n";
    return 0;
}

}

int main(int argc, char** argv)
{
    if (argc < 2) {
        print_help();
        return 1;
    }

    const std::string_view command(argv[1]);
    if (command == "--help" || command == "-h") {
        print_help();
        return 0;
    }

    if (command == "create-document") {
        return create_document(argc, argv);
    }

    if (command == "inspect-image") {
        return inspect_image(argc, argv);
    }

    if (command == "parse-layout") {
        return parse_layout(argc, argv);
    }

    print_error(command, "unknown command");
    return 2;
}