const std = @import("std");

// Although this function looks imperative, note that its job is to
// declaratively construct a build graph that will be executed by an external
// runner.
pub fn build(b: *std.Build) void {
    // Standard target options allows the person running `zig build` to choose
    // what target to build for. Here we do not override the defaults, which
    // means any target is allowed, and the default is native. Other options
    // for restricting supported target set are available.
    const target = b.standardTargetOptions(.{});

    // Standard optimization options allow the person running `zig build` to select
    // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall. Here we do not
    // set a preferred release mode, allowing the user to decide how to optimize.
    const optimize = b.standardOptimizeOption(.{});

    const opt_elf64 = b.option(bool, "elf64", "ELF 64 bit").?;
    const opt_file = b.option(bool, "file", "Get auxiliary vectors from /proc/self/auxv") orelse false;

    const lib = b.addStaticLibrary(.{
        .name = "getauxval-backport",
        .target = target,
        .optimize = optimize,
    });

    lib.linkLibC();

    lib.addCSourceFile(.{
        .file = b.path("src/getauxval_backport.c"),
        .flags = &.{
            if (!opt_elf64) "-DGETAUXVAL_BACKPORT_ELF32" else "",
            if (opt_file) "-DGETAUXVAL_BACKPORT_FILE" else "",
        },
    });

    b.installArtifact(lib);

    // const exe = b.addExecutable(.{
    //     .name = "getauxval-backport",
    //     .root_source_file = b.path("src/main.zig"),
    //     .target = target,
    //     .optimize = optimize,
    // });

    // // This declares intent for the executable to be installed into the
    // // standard location when the user invokes the "install" step (the default
    // // step when running `zig build`).
    // b.installArtifact(exe);

    // // This *creates* a Run step in the build graph, to be executed when another
    // // step is evaluated that depends on it. The next line below will establish
    // // such a dependency.
    // const run_cmd = b.addRunArtifact(exe);

    // // By making the run step depend on the install step, it will be run from the
    // // installation directory rather than directly from within the cache directory.
    // // This is not necessary, however, if the application depends on other installed
    // // files, this ensures they will be present and in the expected location.
    // run_cmd.step.dependOn(b.getInstallStep());

    // // This allows the user to pass arguments to the application in the build
    // // command itself, like this: `zig build run -- arg1 arg2 etc`
    // if (b.args) |args| {
    //     run_cmd.addArgs(args);
    // }

    // // This creates a build step. It will be visible in the `zig build --help` menu,
    // // and can be selected like this: `zig build run`
    // // This will evaluate the `run` step rather than the default, which is "install".
    // const run_step = b.step("run", "Run the app");
    // run_step.dependOn(&run_cmd.step);

    // // Creates a step for unit testing. This only builds the test executable
    // // but does not run it.
    // const lib_unit_tests = b.addTest(.{
    //     .root_source_file = b.path("src/root.zig"),
    //     .target = target,
    //     .optimize = optimize,
    // });

    // const run_lib_unit_tests = b.addRunArtifact(lib_unit_tests);

    // const exe_unit_tests = b.addTest(.{
    //     .root_source_file = b.path("src/main.zig"),
    //     .target = target,
    //     .optimize = optimize,
    // });

    // const run_exe_unit_tests = b.addRunArtifact(exe_unit_tests);

    // // Similar to creating the run step earlier, this exposes a `test` step to
    // // the `zig build --help` menu, providing a way for the user to request
    // // running the unit tests.
    // const test_step = b.step("test", "Run unit tests");
    // test_step.dependOn(&run_lib_unit_tests.step);
    // test_step.dependOn(&run_exe_unit_tests.step);
}