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

// POSIX env helper — std::setenv is non-standard. Linux-only is fine here;
// project.cpp gates this test on x86_64-pc-linux-gnu.
extern "C" int setenv(const char* name, const char* value, int overwrite);

// EnableWasiBrowserRuntime stamps runtime.js, a generated index.html, and a
// files.json manifest onto cfg.files so the build step copies them next to
// the .wasm. We don't run the wasm build here (avoids requiring wasi-sdk +
// the wasi-libc++ PCM rebuild on top of every test); we just verify the
// helper produced the right artifacts and registered them on the config.
int main() {
    Configuration cfg;
    cfg.path = fs::temp_directory_path() / "crafter-build-wasi-runtime-test";
    cfg.name = "wasi-helper";
    cfg.outputName = "wasi-helper";
    cfg.target = "wasm32-wasip1";
    cfg.type = ConfigurationType::Executable;

    std::error_code ec;
    fs::remove_all(cfg.path, ec);
    fs::create_directories(cfg.path);

    // EnableWasiBrowserRuntime looks up runtime.js + index.html.in under
    // GetCrafterBuildHome()/wasi-runtime. The test binary lives in
    // bin/<variant>/, so the auto-detect walks parents and won't find a
    // share/crafter-build/Crafter.Build.cppm anchor — point CRAFTER_BUILD_HOME
    // at the repo root (cwd when crafter-build test runs) so it picks up
    // ./wasi-runtime/. Probe both repo root and the system-installed share
    // dir to also work from a packaged checkout.
    fs::path repoWasi = fs::current_path() / "wasi-runtime";
    fs::path systemHome = "/usr/local/share/crafter-build";
    if (fs::exists(repoWasi / "runtime.js")) {
        setenv("CRAFTER_BUILD_HOME", fs::current_path().c_str(), 1);
    } else if (fs::exists(systemHome / "wasi-runtime" / "runtime.js")) {
        setenv("CRAFTER_BUILD_HOME", systemHome.c_str(), 1);
    } else {
        std::println(std::cerr,
            "wasi-runtime assets not found near {} or {}",
            repoWasi.string(), systemHome.string());
        return 77;  // skipped — environmental, not a code defect
    }

    EnableWasiBrowserRuntime(cfg);

    // Three files registered: runtime.js, generated index.html, files.json.
    if (cfg.files.size() != 3) {
        std::println(std::cerr, "expected 3 cfg.files entries, got {}", cfg.files.size());
        for (const auto& f : cfg.files) std::println(std::cerr, "  - {}", f.string());
        return 1;
    }

    auto findByName = [&](std::string_view name) -> const fs::path* {
        for (const fs::path& f : cfg.files) {
            if (f.filename() == name) return &f;
        }
        return nullptr;
    };

    const fs::path* runtimeJs = findByName("runtime.js");
    const fs::path* indexHtml = findByName("index.html");
    const fs::path* manifest = findByName("files.json");

    if (!runtimeJs) { std::println(std::cerr, "runtime.js not registered"); return 1; }
    if (!indexHtml) { std::println(std::cerr, "index.html not registered"); return 1; }
    if (!manifest)  { std::println(std::cerr, "files.json not registered"); return 1; }

    // The generated index.html and manifest live under the project's build/
    // wasi-runtime/<name>/ directory and must actually exist on disk.
    if (!fs::exists(*indexHtml)) {
        std::println(std::cerr, "index.html not produced at {}", indexHtml->string());
        return 1;
    }
    if (!fs::exists(*manifest)) {
        std::println(std::cerr, "files.json not produced at {}", manifest->string());
        return 1;
    }

    // The template's {{WASM}} placeholder should have been replaced with
    // the configured outputName.
    std::ifstream in(*indexHtml);
    std::string html{std::istreambuf_iterator<char>(in), std::istreambuf_iterator<char>()};
    if (html.find("wasi-helper.wasm") == std::string::npos) {
        std::println(std::cerr, "index.html missing wasi-helper.wasm reference");
        return 1;
    }
    if (html.find("{{WASM}}") != std::string::npos) {
        std::println(std::cerr, "index.html still contains unreplaced {{WASM}} placeholder");
        return 1;
    }

    fs::remove_all(cfg.path, ec);
    return 0;
}