#include "clang/Tooling/Tooling.h"
#include "clang/Tooling/CompilationDatabase.h"

#include "llvm/Support/Signals.h"

#include <iostream>
#include <string>

#include "interface.h"

using namespace clang::tooling;

void print_usage(const char* program_name) {
    std::cerr << "Usage: " << program_name << " <filename> <libname> <gen_target> <output_filename> -- <clang_flags>\n";
}

int main(int argc, char* argv[]) {
    llvm::sys::PrintStackTraceOnErrorSignal(argv[0]);

    if (argc < 6) {
        print_usage(argv[0]);
        return EXIT_FAILURE;
    }

    // Parse compile flags after "--" (this updates argc to the index of the "--" separator)
    std::string error;
    auto compile_db = FixedCompilationDatabase::loadFromCommandLine(argc, argv, error);
    if (!compile_db) {
        print_usage(argv[0]);
        std::cerr << "\nError: " << error << "\n";
        return EXIT_FAILURE;
    }

    // Process arguments before the "--" separator
    if (argc != 5) {
        print_usage(argv[0]);
        return EXIT_FAILURE;
    }

    char** arg = argv + 1;
    const auto filename = *arg++;
    const std::string libname = *arg++;
    const std::string target_abi = *arg++;
    const std::string output_filename = *arg++;

    OutputFilenames output_filenames;
    if (target_abi == "-host") {
        output_filenames.host = output_filename;
    } else if (target_abi == "-guest") {
        output_filenames.guest = output_filename;
    } else {
        std::cerr << "Unrecognized generator target ABI \"" << target_abi << "\"\n";
        return EXIT_FAILURE;
    }

    ClangTool Tool(*compile_db, { filename });
    if (CLANG_RESOURCE_DIR[0] != 0) {
        auto set_resource_directory = [](const clang::tooling::CommandLineArguments &Args, clang::StringRef) {
            clang::tooling::CommandLineArguments AdjustedArgs = Args;
            AdjustedArgs.push_back(std::string { "-resource-dir=" } + CLANG_RESOURCE_DIR);
            return AdjustedArgs;
        };
        Tool.appendArgumentsAdjuster(set_resource_directory);
    }
    return Tool.run(std::make_unique<GenerateThunkLibsActionFactory>(std::move(libname), std::move(output_filenames)).get());
}