const std = @import("std");

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

    const c_flags = [_][]const u8{
        "-std=c99",
        "-Wall",
        "-Wextra",
        "-O2",
    };

    // RNG library
    const rng_lib = b.addLibrary(.{
        .name = "rng",
        .root_module = b.createModule(.{
            .target = target,
            .optimize = optimize,
            .link_libc = true,
        }),
    });
    rng_lib.addCSourceFiles(.{
        .files = &[_][]const u8{"libs/rng/rng.c"},
        .flags = &c_flags,
    });
    rng_lib.addIncludePath(b.path("libs/rng"));

    // Map library
    const map_lib = b.addLibrary(.{
        .name = "map",
        .root_module = b.createModule(.{
            .target = target,
            .optimize = optimize,
            .link_libc = true,
        }),
    });
    map_lib.addCSourceFiles(.{
        .files = &[_][]const u8{
            "libs/map/map.c",
            "libs/map/utils.c",
        },
        .flags = &c_flags,
    });
    // map.h includes common.h and settings.h which live in src/
    map_lib.addIncludePath(b.path("src"));
    // map.c includes rng/rng.h via libs/ root
    map_lib.addIncludePath(b.path("libs"));
    // utils.h is co-located with map.c
    map_lib.addIncludePath(b.path("libs/map"));

    // Zig combat library
    const combat_lib = b.addLibrary(.{
        .name = "combat",
        .root_module = b.createModule(.{
            .root_source_file = b.path("libs/combat/combat.zig"),
            .target = target,
            .optimize = optimize,
            .link_libc = true,
        }),
    });
    // common.h and settings.h live in src/; rng.h exposed bare from libs/rng
    combat_lib.addIncludePath(b.path("src"));
    combat_lib.addIncludePath(b.path("libs/rng"));

    // C sources remaining in src/
    const c_sources = [_][]const u8{
        "src/audio.c",
        "src/enemy.c",
        "src/items.c",
        "src/main.c",
        "src/movement.c",
        "src/player.c",
        "src/render.c",
        "src/settings.c",
    };

    // Main executable
    const exe = b.addExecutable(.{
        .name = "roguelike",
        .root_module = b.createModule(.{
            .target = target,
            .optimize = optimize,
            .link_libc = true,
        }),
    });

    exe.addCSourceFiles(.{
        .files = &c_sources,
        .flags = &c_flags,
    });

    // src/ for own headers; libs/ so "rng/rng.h" and "map/map.h" resolve
    exe.addIncludePath(b.path("src"));
    exe.addIncludePath(b.path("libs"));

    exe.linkLibrary(rng_lib);
    exe.linkLibrary(map_lib);
    exe.linkLibrary(combat_lib);
    exe.linkSystemLibrary("raylib");
    exe.linkSystemLibrary("m");
    exe.linkSystemLibrary("pthread");
    exe.linkSystemLibrary("dl");
    exe.linkSystemLibrary("rt");

    b.installArtifact(exe);

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