#include "vcpkg_Commands.h"
#include "vcpkg.h"
#include <fstream>
#include "vcpkg_Environment.h"
#include "metrics.h"
#include "vcpkg_Files.h"
#include "post_build_lint.h"
#include "vcpkg_System.h"
#include "vcpkg_Dependencies.h"
#include "vcpkg_Input.h"
#include "vcpkg_Maps.h"
#include "vcpkg_info.h"

namespace vcpkg
{
    using Dependencies::package_spec_with_install_plan;
    using Dependencies::install_plan_type;

    static const std::string OPTION_CHECKS_ONLY = "--checks-only";

    static void create_binary_control_file(const vcpkg_paths& paths, const SourceParagraph& source_paragraph, const triplet& target_triplet)
    {
        const BinaryParagraph bpgh = BinaryParagraph(source_paragraph, target_triplet);
        const fs::path binary_control_file = paths.packages / bpgh.dir() / "CONTROL";
        std::ofstream(binary_control_file) << bpgh;
    }

    static void build_internal(const SourceParagraph& source_paragraph, const package_spec& spec, const vcpkg_paths& paths, const fs::path& port_dir)
    {
        Checks::check_exit(spec.name() == source_paragraph.name, "inconsistent arguments to build_internal()");
        const triplet& target_triplet = spec.target_triplet();

        const fs::path ports_cmake_script_path = paths.ports_cmake;
        const std::wstring command = Strings::wformat(LR"("%%VS140COMNTOOLS%%..\..\VC\vcvarsall.bat" %s && cmake -DCMD=BUILD -DPORT=%s -DTARGET_TRIPLET=%s "-DCURRENT_PORT_DIR=%s/." -P "%s")",
                                                      Strings::utf8_to_utf16(target_triplet.architecture()),
                                                      Strings::utf8_to_utf16(source_paragraph.name),
                                                      Strings::utf8_to_utf16(target_triplet.canonical_name()),
                                                      port_dir.generic_wstring(),
                                                      ports_cmake_script_path.generic_wstring());

        System::Stopwatch2 timer;
        timer.start();
        int return_code = System::cmd_execute(command);
        timer.stop();
        TrackMetric("buildtimeus-" + to_string(spec), timer.microseconds());

        if (return_code != 0)
        {
            System::println(System::color::error, "Error: building package %s failed", to_string(spec));
            System::println("Please ensure sure you're using the latest portfiles with `vcpkg update`, then\n"
                            "submit an issue at https://github.com/Microsoft/vcpkg/issues including:\n"
                            "  Package: %s\n"
                            "  Vcpkg version: %s\n"
                            "\n"
                            "Additionally, attach any relevant sections from the log files above."
                            , to_string(spec), Info::version());
            TrackProperty("error", "build failed");
            TrackProperty("build_error", to_string(spec));
            exit(EXIT_FAILURE);
        }

        PostBuildLint::perform_all_checks(spec, paths);

        create_binary_control_file(paths, source_paragraph, target_triplet);

        // const fs::path port_buildtrees_dir = paths.buildtrees / spec.name;
        // delete_directory(port_buildtrees_dir);
    }

    static void install_and_write_listfile(const vcpkg_paths& paths, const BinaryParagraph& bpgh)
    {
        std::fstream listfile(paths.listfile_path(bpgh), std::ios_base::out | std::ios_base::binary | std::ios_base::trunc);

        auto package_prefix_path = paths.package_dir(bpgh.spec);
        auto prefix_length = package_prefix_path.native().size();

        const triplet& target_triplet = bpgh.spec.target_triplet();
        const std::string& target_triplet_as_string = target_triplet.canonical_name();
        std::error_code ec;
        fs::create_directory(paths.installed / target_triplet_as_string, ec);
        listfile << target_triplet << "\n";

        for (auto it = fs::recursive_directory_iterator(package_prefix_path); it != fs::recursive_directory_iterator(); ++it)
        {
            const std::string filename = it->path().filename().generic_string();
            if (fs::is_regular_file(it->status()) && (_stricmp(filename.c_str(), "CONTROL") == 0 || _stricmp(filename.c_str(), "BUILD_INFO") == 0))
            {
                // Do not copy the control file
                continue;
            }

            auto suffix = it->path().generic_u8string().substr(prefix_length + 1);
            auto target = paths.installed / target_triplet_as_string / suffix;

            auto status = it->status(ec);
            if (ec)
            {
                System::println(System::color::error, "failed: %s: %s", it->path().u8string(), ec.message());
                continue;
            }
            if (fs::is_directory(status))
            {
                fs::create_directory(target, ec);
                if (ec)
                {
                    System::println(System::color::error, "failed: %s: %s", target.u8string(), ec.message());
                }

                listfile << target_triplet << "/" << suffix << "\n";
            }
            else if (fs::is_regular_file(status))
            {
                fs::copy_file(*it, target, ec);
                if (ec)
                {
                    System::println(System::color::error, "failed: %s: %s", target.u8string(), ec.message());
                }
                listfile << target_triplet << "/" << suffix << "\n";
            }
            else if (!fs::status_known(status))
            {
                System::println(System::color::error, "failed: %s: unknown status", it->path().u8string());
            }
            else
                System::println(System::color::error, "failed: %s: cannot handle file type", it->path().u8string());
        }

        listfile.close();
    }

    static std::map<std::string, fs::path> remove_first_n_chars_and_map(const std::vector<fs::path> absolute_paths, const size_t n)
    {
        std::map<std::string, fs::path> output;

        for (const fs::path& absolute_path : absolute_paths)
        {
            std::string suffix = absolute_path.generic_string();
            suffix.erase(0, n);
            output.emplace(suffix, absolute_path);
        }

        return output;
    }

    static void print_map_values(const std::vector<std::string> keys, const std::map<std::string, fs::path>& map)
    {
        System::println("");
        for (const std::string& key : keys)
        {
            System::println("    %s", map.at(key).generic_string());
        }
        System::println("");
    }

    static void install_package(const vcpkg_paths& paths, const BinaryParagraph& binary_paragraph, StatusParagraphs& status_db)
    {
        const fs::path package_dir = paths.package_dir(binary_paragraph.spec);
        const std::vector<fs::path> package_files = Files::recursive_find_all_files_in_dir(package_dir);

        const fs::path installed_dir = paths.installed / binary_paragraph.spec.target_triplet().canonical_name();
        const std::vector<fs::path> installed_files = Files::recursive_find_all_files_in_dir(installed_dir);

        const std::map<std::string, fs::path> package_files_relative_paths_to_absolute_paths = remove_first_n_chars_and_map(package_files, package_dir.generic_string().size() + 1);
        const std::map<std::string, fs::path> installed_files_relative_paths_to_absolute_paths = remove_first_n_chars_and_map(installed_files, installed_dir.generic_string().size() + 1);

        const std::vector<std::string> package_files_set = Maps::extract_keys(package_files_relative_paths_to_absolute_paths);
        const std::vector<std::string> installed_files_set = Maps::extract_keys(installed_files_relative_paths_to_absolute_paths);

        std::vector<std::string> intersection;
        std::set_intersection(package_files_set.cbegin(), package_files_set.cend(),
                              installed_files_set.cbegin(), installed_files_set.cend(),
                              std::back_inserter(intersection));

        if (!intersection.empty())
        {
            System::println(System::color::error, "The following files are already installed and are in conflict with %s:", binary_paragraph.spec);
            print_map_values(intersection, installed_files_relative_paths_to_absolute_paths);
            exit(EXIT_FAILURE);
        }

        StatusParagraph spgh;
        spgh.package = binary_paragraph;
        spgh.want = want_t::install;
        spgh.state = install_state_t::half_installed;
        for (auto&& dep : spgh.package.depends)
        {
            if (status_db.find_installed(dep, spgh.package.spec.target_triplet()) == status_db.end())
            {
                Checks::unreachable();
            }
        }
        write_update(paths, spgh);
        status_db.insert(std::make_unique<StatusParagraph>(spgh));

        install_and_write_listfile(paths, spgh.package);

        spgh.state = install_state_t::installed;
        write_update(paths, spgh);
        status_db.insert(std::make_unique<StatusParagraph>(spgh));
    }

    void install_command(const vcpkg_cmd_arguments& args, const vcpkg_paths& paths, const triplet& default_target_triplet)
    {
        static const std::string example = create_example_string("install zlib zlib:x64-windows curl boost");
        args.check_min_arg_count(1, example.c_str());
        StatusParagraphs status_db = database_load_check(paths);

        std::vector<package_spec> specs = Input::check_and_get_package_specs(args.command_arguments, default_target_triplet, example.c_str());
        Input::check_triplets(specs, paths);
        std::vector<package_spec_with_install_plan> install_plan = Dependencies::create_install_plan(paths, specs, status_db);
        Checks::check_exit(!install_plan.empty(), "Install plan cannot be empty");

        std::string specs_string = to_string(install_plan[0].spec);
        for (size_t i = 1; i < install_plan.size(); ++i)
        {
            specs_string.push_back(',');
            specs_string.append(to_string(install_plan[i].spec));
        }
        TrackProperty("installplan", specs_string);
        Environment::ensure_utilities_on_path(paths);

        for (const package_spec_with_install_plan& action : install_plan)
        {
            try
            {
                if (action.plan.type == install_plan_type::ALREADY_INSTALLED)
                {
                    if (std::find(specs.begin(), specs.end(), action.spec) != specs.end())
                    {
                        System::println(System::color::success, "Package %s is already installed", action.spec);
                    }
                }
                else if (action.plan.type == install_plan_type::BUILD_AND_INSTALL)
                {
                    build_internal(*action.plan.spgh, action.spec, paths, paths.port_dir(action.spec));
                    const BinaryParagraph bpgh = try_load_cached_package(paths, action.spec).get_or_throw();
                    install_package(paths, bpgh, status_db);
                    System::println(System::color::success, "Package %s is installed", action.spec);
                }
                else if (action.plan.type == install_plan_type::INSTALL)
                {
                    install_package(paths, *action.plan.bpgh, status_db);
                    System::println(System::color::success, "Package %s is installed", action.spec);
                }
                else
                    Checks::unreachable();
            }
            catch (const std::exception& e)
            {
                System::println(System::color::error, "Error: Could not install package %s: %s", action.spec, e.what());
                exit(EXIT_FAILURE);
            }
        }

        exit(EXIT_SUCCESS);
    }

    void build_command(const vcpkg_cmd_arguments& args, const vcpkg_paths& paths, const triplet& default_target_triplet)
    {
        static const std::string example = create_example_string("build zlib:x64-windows");

        // Installing multiple packages leads to unintuitive behavior if one of them depends on another.
        // Allowing only 1 package for now.

        args.check_exact_arg_count(1, example.c_str());

        StatusParagraphs status_db = database_load_check(paths);

        const package_spec spec = Input::check_and_get_package_spec(args.command_arguments.at(0), default_target_triplet, example.c_str());
        Input::check_triplet(spec.target_triplet(), paths);

        const std::unordered_set<std::string> options = args.check_and_get_optional_command_arguments({OPTION_CHECKS_ONLY});
        if (options.find(OPTION_CHECKS_ONLY) != options.end())
        {
            PostBuildLint::perform_all_checks(spec, paths);
            exit(EXIT_SUCCESS);
        }

        // Explicitly load and use the portfile's build dependencies when resolving the build command (instead of a cached package's dependencies).
        const expected<SourceParagraph> maybe_spgh = try_load_port(paths, spec.name());
        Checks::check_exit(!maybe_spgh.error_code(), "Could not find package named %s: %s", spec, maybe_spgh.error_code().message());
        const SourceParagraph& spgh = *maybe_spgh.get();

        const std::vector<std::string> first_level_deps = filter_dependencies(spgh.depends, spec.target_triplet());

        std::vector<package_spec> first_level_deps_specs;
        for (const std::string& dep : first_level_deps)
        {
            first_level_deps_specs.push_back(package_spec::from_name_and_triplet(dep, spec.target_triplet()).get_or_throw());
        }

        std::vector<package_spec_with_install_plan> unmet_dependencies = Dependencies::create_install_plan(paths, first_level_deps_specs, status_db);
        unmet_dependencies.erase(
            std::remove_if(unmet_dependencies.begin(), unmet_dependencies.end(), [](const package_spec_with_install_plan& p)
                           {
                               return p.plan.type == install_plan_type::ALREADY_INSTALLED;
                           }),
            unmet_dependencies.end());

        if (!unmet_dependencies.empty())
        {
            System::println(System::color::error, "The build command requires all dependencies to be already installed.");
            System::println("The following dependencies are missing:");
            System::println("");
            for (const package_spec_with_install_plan& p : unmet_dependencies)
            {
                System::println("    %s", to_string(p.spec));
            }
            System::println("");
            exit(EXIT_FAILURE);
        }

        Environment::ensure_utilities_on_path(paths);
        build_internal(spgh, spec, paths, paths.port_dir(spec));
        exit(EXIT_SUCCESS);
    }

    void build_external_command(const vcpkg_cmd_arguments& args, const vcpkg_paths& paths, const triplet& default_target_triplet)
    {
        static const std::string example = create_example_string(R"(build_external zlib2 C:\path\to\dir\with\controlfile\)");
        args.check_exact_arg_count(2, example.c_str());

        expected<package_spec> maybe_current_spec = package_spec::from_string(args.command_arguments[0], default_target_triplet);
        if (auto spec = maybe_current_spec.get())
        {
            Input::check_triplet(spec->target_triplet(), paths);
            Environment::ensure_utilities_on_path(paths);
            const fs::path port_dir = args.command_arguments.at(1);
            const expected<SourceParagraph> maybe_spgh = try_load_port(port_dir);
            if (auto spgh = maybe_spgh.get())
            {
                build_internal(*spgh, *spec, paths, port_dir);
                exit(EXIT_SUCCESS);
            }
        }

        System::println(System::color::error, "Error: %s: %s", maybe_current_spec.error_code().message(), args.command_arguments[0]);
        print_example(Strings::format("%s zlib:x64-windows", args.command).c_str());
        exit(EXIT_FAILURE);
    }
}