const std = @import("std");

pub fn build(b: *std.Build) void {
    const target = b.standardTargetOptions(.{});
    const optimize = b.standardOptimizeOption(.{});

    const mod = b.addModule("danos", .{
        .root_source_file = b.path("src/root.zig"),
        .target = target,
    });

    const exe = b.addExecutable(.{
        .name = "danos",
        .root_module = b.createModule(.{
            .root_source_file = b.path("src/main.zig"),
            .target = target,
            .optimize = optimize,
            .imports = &.{
                .{ .name = "danos", .module = mod },
            },
        }),
    });

    b.installArtifact(exe);

    const efiexe = b.addExecutable(.{
        .name = "BOOTX64",
        .root_module = b.createModule(.{
            .root_source_file = b.path("src/efi.zig"),
            .target = b.resolveTargetQuery(.{
                .cpu_arch = .x86_64,
                .os_tag = .uefi,
            }),
            .optimize = optimize,
        }),
    });

    b.installArtifact(efiexe);

    // --- run-efi: boot BOOTX64.efi in QEMU with OVMF firmware ---
    // OVMF paths follow the Arch (edk2-ovmf) layout; override with -Dovmf-code
    // and -Dovmf-vars if your distro installs them elsewhere.
    const ovmf_code = b.option(
        []const u8,
        "ovmf-code",
        "Path to the OVMF_CODE firmware image",
    ) orelse "/usr/share/edk2/x64/OVMF_CODE.4m.fd";
    const ovmf_vars = b.option(
        []const u8,
        "ovmf-vars",
        "Path to the OVMF_VARS firmware image (a writable copy is made)",
    ) orelse "/usr/share/edk2/x64/OVMF_VARS.4m.fd";

    // Assemble an EFI System Partition layout: esp/EFI/BOOT/BOOTX64.efi
    const efi_install = b.addInstallArtifact(efiexe, .{
        .dest_dir = .{ .override = .{ .custom = "esp/EFI/BOOT" } },
    });

    // The firmware needs to write NVRAM, so give it a writable copy of the vars.
    const vars_copy = b.addSystemCommand(&.{ "cp", "-f", ovmf_vars });
    const vars_out = vars_copy.addOutputFileArg("OVMF_VARS.4m.fd");

    const run_efi = b.addSystemCommand(&.{
        "qemu-system-x86_64",
        "-machine",
        "q35",
        "-m",
        "128M",
        "-drive",
        b.fmt("if=pflash,format=raw,readonly=on,file={s}", .{ovmf_code}),
    });
    run_efi.addArg("-drive");
    run_efi.addPrefixedFileArg("if=pflash,format=raw,file=", vars_out);
    // Present the ESP directory to the guest as a FAT drive.
    run_efi.addArgs(&.{
        "-drive",
        b.fmt("format=raw,file=fat:rw:{s}/esp", .{b.install_path}),
        "-net",
        "none",
    });
    run_efi.step.dependOn(&efi_install.step);

    const run_efi_step = b.step("run-efi", "Boot the EFI app in QEMU (OVMF)");
    run_efi_step.dependOn(&run_efi.step);

    // const run_cmd = b.addRunArtifact(exe);
    // const run_step = b.step("run", "Run the app");
    // run_step.dependOn(&run_cmd.step);
    // run_cmd.step.dependOn(b.getInstallStep());
    //
    // if (b.args) |args| {
    //     run_cmd.addArgs(args);
    // }

    const mod_tests = b.addTest(.{
        .root_module = mod,
    });

    const run_mod_tests = b.addRunArtifact(mod_tests);

    const exe_tests = b.addTest(.{
        .root_module = exe.root_module,
    });

    const run_exe_tests = b.addRunArtifact(exe_tests);

    const test_step = b.step("test", "Run tests");
    test_step.dependOn(&run_mod_tests.step);
    test_step.dependOn(&run_exe_tests.step);
}