const std = @import("std");

pub fn addShaderDefinition(
    b: *std.Build,
    comptime sdl3Path: []const u8,
    optimize: std.builtin.OptimizeMode,
    shaderName: []const u8,
    jsonPath: std.Build.LazyPath,
) *std.Build.Module {
    const reflectedZig = b.addSystemCommand(&[_][]const u8{"python"});
    reflectedZig.addArg(sdl3Path ++ "/spvreflect/spvreflect.py");
    reflectedZig.addFileArg(jsonPath);
    reflectedZig.addArg("--output");

    const reflectedZigOut = reflectedZig.addOutputFileArg(b.fmt("reflected/{s}.zig", .{shaderName}));
    const module = b.createModule(.{ .root_source_file = reflectedZigOut, .optimize = optimize });

    const dep = b.dependency("shaderTypes", .{
        .target = b.graph.host,
        .optimize = optimize,
    });
    module.addImport("shaderTypes", dep.module("shaderTypes"));

    return module;
}

pub fn shaderDefintion(
    b: *std.Build,
    module: *std.Build.Module,
    comptime sdl3Path: []const u8,
    optimize: std.builtin.OptimizeMode,
    shaderName: []const u8,
    jsonPath: std.Build.LazyPath,
) void {
    const mod = addShaderDefinition(b, sdl3Path, optimize, shaderName, jsonPath);
    module.addImport(shaderName, mod);
}

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

    const sdl_dep = b.dependency("sdl", .{
        .target = target,
        .optimize = optimize,
    });

    const sdl3_lib = sdl_dep.artifact("SDL3");

    const mod = b.addModule("sdl3", .{
        .target = target,
        .optimize = optimize,
        .root_source_file = b.path("src/sdl3.zig"),
    });

    mod.addIncludePath(b.path("SDL/include"));
    mod.linkLibrary(sdl3_lib);

    const test_step = b.step("test", "run unit tests for sdl3");
    const tests = b.addExecutable(.{
        .name = "hello-triangle",
        .target = target,
        .optimize = optimize,
        .root_source_file = b.path("src/samples/hello-triangle.zig"),
        .link_libc = true,
    });

    tests.root_module.addImport("sdl3", mod);

    const vertexDefinitions = addShaderDefinition(b, ".", optimize, "hello-triangle.vert", b.path("content/hello-triangle.vert.json"));
    tests.root_module.addImport("hello-triangle.vert", vertexDefinitions);

    const runArtifact = b.addRunArtifact(tests);
    test_step.dependOn(&runArtifact.step);

    b.installArtifact(tests);
}