const std = @import("std");

///
/// Builds the engine, tools, and dependencies of all.
///
pub fn build(builder: *std.build.Builder) void {
    const target = builder.standardTargetOptions(.{});
    const mode = builder.standardReleaseOptions();
    const ona_pkg = projectPkg("ona", &.{});

    // Engine executable.
    {
        const engine_exe = builder.addExecutable("ona", "./src/engine/main.zig");
        const oar_pkg = projectPkg("oar", &.{ona_pkg});

        engine_exe.addPackage(oar_pkg);
        engine_exe.addPackage(ona_pkg);
        engine_exe.setTarget(target);
        engine_exe.setBuildMode(mode);
        engine_exe.install();
        engine_exe.addIncludeDir("./ext");
        engine_exe.linkSystemLibrary("SDL2");
        engine_exe.linkLibC();

        const run_cmd = engine_exe.run();

        run_cmd.step.dependOn(builder.getInstallStep());

        if (builder.args) |args| run_cmd.addArgs(args);

        builder.step("run", "Run Ona application").dependOn(&run_cmd.step);
    }

    // Oar executable.
    {

    }

    // Ona tests.
    {
        const ona_tests = builder.addTestExe("test", "./src/main.zig");

        ona_tests.setTarget(target);
        ona_tests.setBuildMode(mode);
        builder.step("test", "Run Ona unit tests").dependOn(&ona_tests.step);
    }
}

///
/// Returns a [std.build.Pkg] within the project codebase path at `name` with `dependencies` as its
/// dependencies.
///
fn projectPkg(comptime name: []const u8, dependencies: []const std.build.Pkg) std.build.Pkg {
    return std.build.Pkg{
        .name = name,
        .path = .{.path = "./src/" ++ name ++ "/main.zig"},
        .dependencies = dependencies,
    };
}