# Copyright 2013 The Flutter Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

_skia_root = "//flutter/third_party/skia"

import("$_skia_root/gn/skia.gni")
import("$_skia_root/gn/toolchain/wasm.gni")
import("$_skia_root/modules/canvaskit/canvaskit.gni")

# Defines a WASM library target.
template("canvaskit_wasm_lib") {
  _vars_to_forward = [
    "cflags",
    "check_includes",
    "ldflags",
    "defines",
    "deps",
    "includes",
    "sources",
    "include_dirs",
    "public_configs",
    "testonly",
    "visibility",
  ]

  _lib_name = target_name

  executable("${_lib_name}_js") {
    forward_variables_from(invoker, _vars_to_forward)
    output_extension = "js"
    output_name = "${_lib_name}"
  }

  group("$_lib_name") {
    public_deps = [ ":${_lib_name}_js" ]
  }
}

canvaskit_wasm_lib("canvaskit") {
  # Opted out of check_includes, due to (logically) being part of skia.
  check_includes = false
  deps = [ "../..:skia" ]
  if (skia_canvaskit_enable_paragraph) {
    deps += [
      "../../modules/skparagraph",
      "../../modules/skunicode",
    ]
  }
  if (skia_canvaskit_enable_bidi) {
    deps += [ "../../modules/skunicode" ]
  }

  sources = [
    "$_skia_root/modules/canvaskit/WasmCommon.h",
    "$_skia_root/modules/canvaskit/canvaskit_bindings.cpp",
  ]
  if (skia_canvaskit_enable_paragraph) {
    sources += [
      "$_skia_root/modules/canvaskit/paragraph_bindings.cpp",
      "$_skia_root/modules/canvaskit/paragraph_bindings_gen.cpp",
    ]
  }

  if (skia_canvaskit_enable_bidi) {
    sources += [
      "$_skia_root/modules/canvaskit/bidi_bindings.cpp",
      "$_skia_root/modules/canvaskit/bidi_bindings_gen.cpp",
    ]
  }

  ldflags = []
  if (is_debug) {
    ldflags += [
      "-O1",
      "-sASSERTIONS=1",
      "-sGL_ASSERTIONS=1",
      "-g3",
      "--pre-js",
      rebase_path("$_skia_root/modules/canvaskit/debug.js"),
    ]
  } else {
    externs_path = rebase_path("$_skia_root/modules/canvaskit/externs.js")
    ldflags += [
      "-Oz",
      "--closure=1",
      "--pre-js",
      rebase_path("$_skia_root/modules/canvaskit/release.js"),
      "--closure-args=--externs=$externs_path",
    ]
  }
  if (skia_canvaskit_profile_build) {
    ldflags += [
      "--profiling-funcs",
      "--closure=0",
    ]
  }
  ldflags += [ "-fno-rtti" ]

  if (skia_canvaskit_enable_webgl) {
    ldflags += [
      "-lGL",
      "--pre-js",
      rebase_path("$_skia_root/modules/canvaskit/cpu.js"),
      "--pre-js",
      rebase_path("$_skia_root/modules/canvaskit/webgl.js"),
      "-sUSE_WEBGL2=1",
      "-sMAX_WEBGL_VERSION=2",
    ]
  } else {
    ldflags += [
      "--pre-js",
      rebase_path("$_skia_root/modules/canvaskit/cpu.js"),
      "-sUSE_WEBGL2=0",
    ]
  }

  ldflags += [
    "-std=c++17",
    "--bind",
    "--no-entry",
    "--pre-js",
    rebase_path("$_skia_root/modules/canvaskit/util.js"),
    "--pre-js",
    rebase_path("$_skia_root/modules/canvaskit/preamble.js"),
    "--pre-js",
    rebase_path("$_skia_root/modules/canvaskit/color.js"),
    "--pre-js",
    rebase_path("$_skia_root/modules/canvaskit/memory.js"),
    "--pre-js",
    rebase_path("$_skia_root/modules/canvaskit/interface.js"),
  ]

  if (skia_canvaskit_enable_paragraph) {
    ldflags += [
      "--pre-js",
      rebase_path("$_skia_root/modules/canvaskit/paragraph.js"),
    ]
  }

  if (skia_canvaskit_enable_bidi) {
    ldflags += [
      "--pre-js",
      rebase_path("$_skia_root/modules/canvaskit/bidi.js"),
    ]
  }

  if (skia_canvaskit_enable_pathops) {
    ldflags += [
      "--pre-js",
      rebase_path("$_skia_root/modules/canvaskit/pathops.js"),
    ]
  }

  if (skia_canvaskit_enable_font) {
    ldflags += [
      "--pre-js",
      rebase_path("$_skia_root/modules/canvaskit/font.js"),
    ]
  }

  if (skia_canvaskit_enable_skp_serialization) {
    ldflags += [
      "--pre-js",
      rebase_path("$_skia_root/modules/canvaskit/skp.js"),
    ]
  }

  if (skia_canvaskit_enable_rt_shader) {
    ldflags += [
      "--pre-js",
      rebase_path("$_skia_root/modules/canvaskit/rt_shader.js"),
    ]
  }

  ldflags += [
    "--pre-js",
    rebase_path("$_skia_root/modules/canvaskit/postamble.js"),
    "-sALLOW_MEMORY_GROWTH",
    "-sDISABLE_EXCEPTION_CATCHING",
    "-sNODEJS_CATCH_EXIT=0",
    "-sDYNAMIC_EXECUTION=0",
    "-sEXPORT_NAME=CanvasKitInit",
    "-sEXPORTED_FUNCTIONS=[_malloc,_free]",
    "-sEXPORTED_RUNTIME_METHODS=HEAP8,HEAPU8,HEAP16,HEAPU16,HEAP32,HEAPF32,HEAPU32,HEAPF64",
    "-sINCOMING_MODULE_JS_API=[instantiateWasm,onRuntimeInitialized,noExitRuntime]",
    "-sFORCE_FILESYSTEM=0",
    "-sFILESYSTEM=0",
    "-sMODULARIZE",
    "-sNO_EXIT_RUNTIME=1",
    "-sINITIAL_MEMORY=32MB",

    # Grow memory by +100% i.e. double the size each time we run out of memory.
    "-sMEMORY_GROWTH_GEOMETRIC_STEP=1.0",
    "-sWASM",
    "-sSTRICT=1",
  ]

  defines = []
  if (is_debug) {
    defines += [ "SK_DEBUG" ]
  } else {
    defines += [ "SK_RELEASE" ]
  }
  if (!is_debug && !skia_canvaskit_force_tracing) {
    defines += [ "SK_DISABLE_TRACING" ]
  }
  defines += [
    "SK_FORCE_AAA",
    "SK_FORCE_8_BYTE_ALIGNMENT",
    "EMSCRIPTEN_HAS_UNBOUND_TYPE_NAMES=0",
    "SK_SHAPER_HARFBUZZ_AVAILABLE",
  ]
  if (skia_canvaskit_enable_paragraph) {
    defines += [ "CK_INCLUDE_PARAGRAPH" ]
  }
  if (skia_canvaskit_enable_bidi) {
    defines += [ "CK_ENABLE_BIDI" ]
  }
  if (skia_canvaskit_enable_skp_serialization) {
    defines += [ "CK_SERIALIZE_SKP" ]
  }
  if (skia_enable_ganesh) {
    defines += [
      "SK_GANESH",
      "SK_DISABLE_LEGACY_SHADERCONTEXT",
    ]
    if (skia_canvaskit_enable_webgl) {
      defines += [
        "SK_GL",
        "CK_ENABLE_WEBGL",
      ]
    }
  }

  if (skia_canvaskit_enable_pathops) {
    defines += [ "CK_INCLUDE_PATHOPS" ]
  }
  if (skia_canvaskit_enable_rt_shader) {
    defines += [ "CK_INCLUDE_RUNTIME_EFFECT" ]
  }
  if (!skia_canvaskit_enable_alias_font) {
    defines += [ "CK_NO_ALIAS_FONT" ]
  }
  if (!skia_canvaskit_enable_font) {
    defines += [ "CK_NO_FONTS" ]
  }
}