import std;
import Crafter.Build;
namespace fs = std::filesystem;
using namespace Crafter;

extern "C" Configuration CrafterBuildProject(std::span<const std::string_view> args) {
    bool debug = false;
    for (std::string_view arg : args) {
        if (arg == "--debug") debug = true;
    }

    static auto crafterBuildLib = std::make_unique<Configuration>();
    crafterBuildLib->path = "./";
    crafterBuildLib->name = "crafter.build-lib";
    crafterBuildLib->outputName = "crafter-build";
    crafterBuildLib->target = "x86_64-pc-linux-gnu";
    crafterBuildLib->type = ConfigurationType::LibraryStatic;
    crafterBuildLib->debug = debug;
    {
        std::array<fs::path, 8> interfaces = {
            "interfaces/Crafter.Build",
            "interfaces/Crafter.Build-Shader",
            "interfaces/Crafter.Build-Platform",
            "interfaces/Crafter.Build-Interface",
            "interfaces/Crafter.Build-Implementation",
            "interfaces/Crafter.Build-External",
            "interfaces/Crafter.Build-Clang",
            "interfaces/Crafter.Build-Test",
        };
        std::array<fs::path, 7> implementations = {
            "implementations/Crafter.Build-Shader",
            "implementations/Crafter.Build-Platform",
            "implementations/Crafter.Build-Interface",
            "implementations/Crafter.Build-Implementation",
            "implementations/Crafter.Build-External",
            "implementations/Crafter.Build-Clang",
            "implementations/Crafter.Build-Test",
        };
        crafterBuildLib->GetInterfacesAndImplementations(interfaces, implementations);
    }
    ExternalDependency& glslang = crafterBuildLib->externalDependencies.emplace_back();
    glslang.name = "glslang";
    glslang.source.url = "https://github.com/KhronosGroup/glslang.git";
    glslang.source.branch = "main";
    glslang.builder = ExternalBuilder::CMake;
    glslang.options = { "-DENABLE_OPT=OFF" };
    glslang.includeDirs = { "" };
    glslang.libs = { "SPIRV", "GenericCodeGen", "glslang", "OSDependent", "MachineIndependent", "glslang-default-resource-limits" };

    Configuration cfg;
    cfg.path = "./";
    cfg.name = "crafter.build-exe";
    cfg.outputName = "crafter-build";
    cfg.target = "x86_64-pc-linux-gnu";
    cfg.type = ConfigurationType::Executable;
    cfg.debug = debug;
    cfg.dependencies = { crafterBuildLib.get() };
    {
        std::array<fs::path, 0> interfaces = {};
        std::array<fs::path, 1> implementations = { "implementations/main" };
        cfg.GetInterfacesAndImplementations(interfaces, implementations);
    }
    cfg.linkFlags.push_back("-Wl,--export-dynamic");
    cfg.linkFlags.push_back("-ldl");

    // ----- Single-driver, multi-target tests (each appears once per (target, runner)). -----

    // Lifetime holders for per-target lib Configurations referenced by Tests.
    static std::vector<std::unique_ptr<Configuration>> testLibPool;

    struct TargetRunner {
        std::string target;
        TestRunner runner;
        std::vector<std::string> extraLinkFlags;
    };
    std::vector<TargetRunner> targets = {
        { "x86_64-pc-linux-gnu", TestRunner::Local(), {} },
        { "x86_64-w64-mingw32",  TestRunner::SshWin("winvm", "C:/temp/crafter-tests"), {"-lstdc++exp"} },
    };

    auto addPerTarget = [&](std::string name, auto buildOne) {
        for (auto& tr : targets) {
            Test t;
            t.config.name = name;
            t.config.target = tr.target;
            t.config.type = ConfigurationType::Executable;
            t.config.linkFlags.push_back("-fuse-ld=lld");
            for (auto& f : tr.extraLinkFlags) t.config.linkFlags.push_back(f);
            buildOne(t, tr.target);
            t.runner = tr.runner;
            cfg.tests.push_back(std::move(t));
        }
    };

    addPerTarget("HelloWorld", [](Test& t, std::string_view) {
        t.config.path = "tests/fixtures/hello-world/";
        t.config.outputName = "hello";
        std::array<fs::path, 0> ifaces = {};
        std::array<fs::path, 1> impls = { "main" };
        t.config.GetInterfacesAndImplementations(ifaces, impls);
    });

    addPerTarget("WithModule", [](Test& t, std::string_view) {
        t.config.path = "tests/fixtures/with-module/";
        t.config.outputName = "hello-mod";
        std::array<fs::path, 1> ifaces = { "interfaces/Greeter" };
        std::array<fs::path, 1> impls = { "main" };
        t.config.GetInterfacesAndImplementations(ifaces, impls);
    });

    addPerTarget("Defines", [](Test& t, std::string_view) {
        t.config.path = "tests/fixtures/defines/";
        t.config.outputName = "defines-app";
        std::array<fs::path, 0> ifaces = {};
        std::array<fs::path, 1> impls = { "main" };
        t.config.GetInterfacesAndImplementations(ifaces, impls);
        t.config.defines.push_back({"CRAFTER_TEST_FOO", "42"});
    });

    addPerTarget("CrossProjectModule", [&](Test& t, std::string_view target) {
        auto fooLib = std::make_unique<Configuration>();
        fooLib->path = "tests/fixtures/cross-project/lib/";
        fooLib->name = std::format("Foo-cross-project-{}", target);
        fooLib->outputName = "Foo";
        fooLib->target = std::string(target);
        fooLib->type = ConfigurationType::LibraryStatic;
        std::array<fs::path, 1> libIfaces = { "Foo" };
        std::array<fs::path, 0> libImpls = {};
        fooLib->GetInterfacesAndImplementations(libIfaces, libImpls);
        Configuration* fooLibPtr = fooLib.get();
        testLibPool.push_back(std::move(fooLib));

        t.config.path = "tests/fixtures/cross-project/";
        t.config.outputName = "cross-app";
        t.config.dependencies = { fooLibPtr };
        std::array<fs::path, 0> mainIfaces = {};
        std::array<fs::path, 1> mainImpls = { "main" };
        t.config.GetInterfacesAndImplementations(mainIfaces, mainImpls);
    });

    auto makeDiamondLib = [&](std::string_view dir, std::string_view modName,
                              std::string_view target, std::span<Configuration*> deps) {
        auto lib = std::make_unique<Configuration>();
        lib->path = std::format("tests/fixtures/diamond/{}/", dir);
        lib->name = std::format("{}-diamond-{}", modName, target);
        lib->outputName = std::string(modName);
        lib->target = std::string(target);
        lib->type = ConfigurationType::LibraryStatic;
        lib->dependencies.assign(deps.begin(), deps.end());
        std::array<fs::path, 1> ifaces = { fs::path(modName) };
        std::array<fs::path, 0> impls = {};
        lib->GetInterfacesAndImplementations(ifaces, impls);
        return lib;
    };

    addPerTarget("Diamond", [&](Test& t, std::string_view target) {
        auto X = makeDiamondLib("X", "X", target, {});
        Configuration* xDeps[] = { X.get() };
        auto B = makeDiamondLib("B", "B", target, xDeps);
        auto C = makeDiamondLib("C", "C", target, xDeps);
        Configuration* mainDeps[] = { B.get(), C.get() };

        t.config.path = "tests/fixtures/diamond/";
        t.config.outputName = "diamond-app";
        t.config.dependencies.assign(mainDeps, mainDeps + 2);
        std::array<fs::path, 0> ifaces = {};
        std::array<fs::path, 1> impls = { "main" };
        t.config.GetInterfacesAndImplementations(ifaces, impls);

        testLibPool.push_back(std::move(X));
        testLibPool.push_back(std::move(B));
        testLibPool.push_back(std::move(C));
    });

    // ----- Outer-driver tests (still need their own driver source for multi-step
    // logic or meta-runner behavior). -----

    auto addOuterDriverTest = [&](std::string name) {
        Test t;
        t.config.path = "./";
        t.config.name = name;
        t.config.outputName = name;
        t.config.target = "x86_64-pc-linux-gnu";
        t.config.type = ConfigurationType::Executable;
        std::array<fs::path, 0> empty = {};
        std::array<fs::path, 1> impls = { fs::path("tests") / name };
        t.config.GetInterfacesAndImplementations(empty, impls);
        cfg.tests.push_back(std::move(t));
    };

    addOuterDriverTest("Incremental");
    addOuterDriverTest("BuildError");
    addOuterDriverTest("Libraries");
    addOuterDriverTest("RunnerClassification");
    addOuterDriverTest("QemuUser");
    addOuterDriverTest("SshRunner");
    addOuterDriverTest("CrossArchAarch64");
    addOuterDriverTest("WindowsViaSsh");

    return cfg;
}