/*
Crafter® Build
Copyright (C) 2026 Catcrafts®
Catcrafts.net

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License version 3.0 as published by the Free Software Foundation;

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
*/

export module Crafter.Build:Platform_impl;
import std;
import :Platform;
import :Clang;
namespace fs = std::filesystem;
using namespace Crafter;


#if defined(CRAFTER_BUILD_CONFIGURATION_TARGET_x86_64_pc_windows_msvc) || defined(CRAFTER_BUILD_CONFIGURATION_TARGET_x86_64_w64_mingw32)
std::string RunCommand(const std::string_view cmd) {
    std::array<char, 128> buffer;
    std::string result;

    // Use cmd.exe to interpret redirection
    std::string with = "cmd /C \"" + std::string(cmd) + " 2>&1\"";

    FILE* pipe = _popen(with.c_str(), "r");
    if (!pipe) {
        throw std::runtime_error("_popen() failed!");
    }

    while (fgets(buffer.data(), static_cast<int>(buffer.size()), pipe) != nullptr) {
        result += buffer.data();
    }

    _pclose(pipe);
    return result;
}

fs::path BuildStdPcm(Configuration& config, fs::path stdPcm) {
    std::string libcxx = std::getenv("LIBCXX_DIR");
    std::string stdPcm = std::format("{}\\{}{}\\std.pcm", exeDir.string(), config.target, config.march);
    std::string stdcppm = std::format("{}\\modules\\c++\\v1\\std.cppm", libcxx);

    if(!fs::exists(stdPcm) || fs::last_write_time(stdPcm) < fs::last_write_time(stdcppm)) {
        return RunCommand(std::format("clang++ --target={} -march={} -mtune={} -isystem %LIBCXX_DIR%\\include\\c++\\v1 -nostdinc++ -nostdlib++ -std=c++26 -Wno-reserved-identifier -Wno-reserved-module-identifier --precompile %LIBCXX_DIR%\\modules\\c++\\v1\\std.cppm -o {}", config.target, config.march, config.mtune, stdPcm));
    }
}

fs::path GetCacheDir() {
    if (const char* local = std::getenv("LOCALAPPDATA")) {
        return fs::path(local) / "crafter.build";
    }

    throw std::runtime_error("LOCALAPPDATA not set");
}

std::string GetBaseCommand(Configuration& config) {
    return std::format("clang++ -nostdinc++ -nostdlib++ -isystem %LIBCXX_DIR%\\include\\c++\\v1");
}
#endif

#ifdef CRAFTER_BUILD_CONFIGURATION_TARGET_x86_64_pc_linux_gnu

std::string RunCommand(const std::string_view cmd) {
    std::array<char, 128> buffer;
    std::string result;

    std::string with = std::string(cmd) + " 2>&1";
    // Open pipe to file
    FILE* pipe = popen(with.c_str(), "r");
    if (!pipe) throw std::runtime_error("popen() failed!");

    // Read till end of process:
    while (fgets(buffer.data(), buffer.size(), pipe) != nullptr) {
        result += buffer.data();
    }

    // Close pipe
    pclose(pipe);
    return result;
}

fs::path BuildStdPcm(Configuration& config, fs::path stdPcm) {
    if(config.target == "x86_64-w64-mingw32") {
        std::vector<std::string> folders;

        // Iterate through the directory and collect all subdirectories
        for (const auto& entry : fs::directory_iterator("/usr/x86_64-w64-mingw32/include/c++")) {
            if (entry.is_directory()) {
                folders.push_back(entry.path().filename().string());
            }
        }

        // Sort the folders by version in descending order
        std::sort(folders.begin(), folders.end(), [](const std::string& a, const std::string& b) {
            return std::lexicographical_compare(b.begin(), b.end(), a.begin(), a.end());
        });

        std::string mingWversion = folders.front();

        fs::path stdCc = fs::path(std::format("/usr/x86_64-w64-mingw32/include/c++/{}/bits/std.cc", mingWversion));

        if(!fs::exists(stdPcm) || fs::last_write_time(stdPcm) < fs::last_write_time(stdCc)) {
            std::string result = RunCommand(std::format("cp {} {}/{}{}/std.cppm\nclang++ --target={} -march={} -mtune={} -O3 -std=c++26 -Wno-reserved-identifier -Wno-reserved-module-identifier --precompile {}/{}{}/std.cppm -o {}", stdCc.string(), exeDir.string(), config.target, config.march, config.target, config.march, config.mtune, exeDir.string(), config.target, config.march, stdPcm));
            if(!result.empty()) {
                return result;
            }
        }

        try {
            // Iterate over the source directory
            for (const auto& entry : fs::directory_iterator("/usr/x86_64-w64-mingw32/bin/")) {
                // Check if the file is a regular file and ends with ".dll"
                if (fs::is_regular_file(entry) && entry.path().extension() == ".dll") {
                    // Construct the destination file path
                    fs::path dest_file = project.binDir / config.name / entry.path().filename();

                    // Check if the destination file exists and if it is older than the source file
                    if (!fs::exists(dest_file) || fs::last_write_time(entry.path()) > fs::last_write_time(dest_file)) {
                        // Copy the file if it doesn't exist or is older
                        fs::copy(entry.path(), dest_file, fs::copy_options::overwrite_existing);
                    }
                }
            }
        } catch (const fs::filesystem_error& e) {
            return e.what();
        }
    } else {
        if(!fs::exists(stdPcm) || fs::last_write_time(stdPcm) < fs::last_write_time("/usr/share/libc++/v1/std.cppm")) {
            return RunCommand(std::format("clang++ --target={} -std=c++26 -stdlib=libc++ -march={} -mtune={} -O3 -Wno-reserved-identifier -Wno-reserved-module-identifier --precompile /usr/share/libc++/v1/std.cppm -o {}", config.target, config.march, config.mtune, stdPcm));
        }
    }
}

fs::path GetCacheDir() {
    if (const char* xdg = std::getenv("XDG_CACHE_HOME"); xdg && *xdg) {
        return fs::path(xdg) / "crafter.build";
    }
        
    if (const char* home = std::getenv("HOME")) {
        return fs::path(home) / ".cache" / "crafter.build";
    }
        
    throw std::runtime_error("Neither XDG_CACHE_HOME nor HOME set");
}

std::string GetBaseCommand(Configuration& config) {
    std::string stdlib;
    if(config.target == "x86_64-w64-mingw32") {
        stdlib = "";
    } else {
        stdlib = "-stdlib=libc++";
    }
    std::string command = std::format("clang++ {}", stdlib);
}

#endif