const std = @import("std");

pub fn build(b: *std.Build) !void {
  const opengl = b.option(bool, "opengl", "Exposes OpenGL helper functions in RGFW.h and links OpenGL. Default: true") orelse true;
  const x11 = b.option(bool, "x11", "X11 backend. Default: true") orelse true;

  const target = b.standardTargetOptions(.{});
  const optimize = b.standardOptimizeOption(.{});
  var macros = std.ArrayList([2][]const u8).empty;
  defer macros.deinit(b.allocator);
  var syslibs = std.ArrayList(struct {[]const u8, std.Build.Module.LinkSystemLibraryOptions}).empty;
  defer syslibs.deinit(b.allocator);

  try macros.append(b.allocator, [2][]const u8{"RSGL_RFONT", ""});

  if (target.result.os.tag == std.Target.Os.Tag.linux or target.result.os.tag == std.Target.Os.Tag.macos)
    try macros.append(b.allocator, [2][]const u8{"RGFW_UNIX", ""});

  if (x11) {
    try macros.append(b.allocator, [2][]const u8{"RGFW_X11", ""});
    try	syslibs.append(b.allocator, struct {[]const u8, std.Build.Module.LinkSystemLibraryOptions}{"X11", .{}});
    try syslibs.append(b.allocator, struct {[]const u8, std.Build.Module.LinkSystemLibraryOptions}{"Xrandr", .{}});
  } else {
    try macros.append(b.allocator, [2][]const u8{"RGFW_NO_X11", ""});
  }
  if (opengl) {
    try macros.append(b.allocator, [2][]const u8{"RGFW_OPENGL", ""});
    try syslibs.append(b.allocator, struct {[]const u8, std.Build.Module.LinkSystemLibraryOptions}{"GL", .{}});
  } else {
    std.debug.panic("no backend other than OpenGL supported by RSGL.h", .{});
  }

  const rgfw_raw = b.addTranslateC(.{
    .root_source_file = b.path("include/RGFW.h"),
    .target = target,
    .optimize = optimize,
  });
  for (macros.items) |macro| {rgfw_raw.defineCMacro(macro[0], macro[1]);}
  const rgfw_raw_mod = rgfw_raw.addModule("rgfw_raw");

  const rsgl_raw = b.addTranslateC(.{
    .root_source_file = b.path("include/RSGL_gl.h"),
    .target = target,
    .optimize = optimize,
  });
  for (macros.items) |macro| {rsgl_raw.defineCMacro(macro[0], macro[1]);}
  const rsgl_raw_mod = rsgl_raw.addModule("rsgl");

  const rsgl_mod = b.createModule(.{
    .root_source_file = b.path("rsgl.zig"),
    .target = target,
    .optimize = optimize,
    .imports = &.{
      .{.name = "rsgl_raw", .module = rsgl_raw_mod},
    },
  });

  const term = b.createModule(.{
    .root_source_file = b.path("main.zig"),
    .target = target,
    .optimize = optimize,
    .imports = &.{
      .{.name = "rgfw_raw", .module = rgfw_raw_mod},
      .{.name = "rsgl_raw", .module = rsgl_raw_mod},
      .{.name = "rsgl", .module = rsgl_mod},
    },
  });

  term.addCMacro("RGFW_IMPLEMENTATION", "");
  term.addCMacro("RFONT_IMPLEMENTATION", "");
  term.addCMacro("RSGL_IMPLEMENTATION", "");
  for (macros.items) |macro| {term.addCMacro(macro[0], macro[1]);}
  term.addIncludePath(b.path("include"));
  term.addCSourceFile(.{.file = b.addWriteFiles().add("rgfw.c", "#include <RSGL_gl.h>\n#include <RGFW.h>"),});

  for (syslibs.items) |lib| {term.linkSystemLibrary(lib[0], lib[1]);}

  const exe = b.addExecutable(.{
    .name = "term",
    .root_module = term,
  });
  b.installArtifact(exe);

  const run_exe = b.addRunArtifact(exe);
  const run_step = b.step("run", "Run the application");
  run_step.dependOn(&run_exe.step);
}