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

import("//build/config/features.gni")
import("//build/config/ui.gni")
import("//testing/test.gni")
import("//third_party/skia/gn/shared_sources.gni")
import("//third_party/skia/modules/skcms/skcms.gni")
import("features.gni")

if (current_cpu == "arm") {
  import("//build/config/arm.gni")
}
if (current_cpu == "mipsel" || current_cpu == "mips64el") {
  import("//build/config/mips.gni")
}

skia_support_gpu = !is_ios
skia_support_pdf = false

# External-facing config for dependent code.
config("skia_config") {
  include_dirs = [ "//third_party/skia" ]

  defines = [
    "SK_ENCODE_PNG",
    "SK_USER_CONFIG_HEADER=\"../../skia/config/SkPdfiumUserConfig.h\"",
  ]

  if (is_win) {
    defines += [ "SK_FREETYPE_MINIMUM_RUNTIME_VERSION=(((FREETYPE_MAJOR) * 0x01000000) | ((FREETYPE_MINOR) * 0x00010000) | ((FREETYPE_PATCH) * 0x00000100))" ]
  }

  if (is_component_build) {
    defines += [
      "SKIA_DLL",
      "GR_GL_IGNORE_ES3_MSAA=0",
    ]
  }

  if (skia_support_gpu) {
    defines += [ "SK_SUPPORT_GPU=1" ]
  } else {
    defines += [ "SK_SUPPORT_GPU=0" ]
  }

  if (skia_use_gl) {
    defines += [ "SK_GL" ]
  }

  if (is_android) {
    defines += [
      "SK_BUILD_FOR_ANDROID",
      "USE_CHROMIUM_SKIA",
    ]
  }

  if (is_mac) {
    defines += [ "SK_BUILD_FOR_MAC" ]
  }

  if (is_win) {
    defines += [ "GR_GL_FUNCTION_TYPE=__stdcall" ]
  }
}

# Internal-facing config for Skia library code.
config("skia_library_config") {
  defines = []

  # Skia uses C++17 language features in its internal code. Previously Skia was built with
  # "-std=c++17". See http://crbug.com/1257145 for why this was a bad idea.
  cflags_cc = [ "-Wno-c++17-extensions" ]
  cflags_objcc = [ "-Wno-c++17-extensions" ]

  if (is_component_build) {
    defines += [ "SKIA_IMPLEMENTATION=1" ]
  }

  if (current_cpu == "arm") {
    if (arm_use_neon) {
      defines += [ "SK_ARM_HAS_NEON" ]
    } else if (arm_optionally_use_neon) {
      defines += [ "SK_ARM_HAS_OPTIONAL_NEON" ]
    }
  }

  # Settings for text blitting, chosen to approximate the system browser.
  if (is_linux || is_chromeos) {
    defines += [
      "SK_GAMMA_EXPONENT=1.2",
      "SK_GAMMA_CONTRAST=0.2",
    ]
  } else if (is_android) {
    defines += [
      "SK_GAMMA_APPLY_TO_A8",
      "SK_GAMMA_EXPONENT=1.4",
      "SK_GAMMA_CONTRAST=0.0",
    ]
  } else if (is_win) {
    defines += [
      "SK_GAMMA_SRGB",
      "SK_GAMMA_CONTRAST=0.5",
    ]
  } else if (is_mac) {
    defines += [
      "SK_GAMMA_SRGB",
      "SK_GAMMA_CONTRAST=0.0",
    ]
  }

  if (is_android) {
    defines += [
      # Android devices are typically more memory constrained, so default to a
      # smaller glyph cache (it may be overriden at runtime when the renderer
      # starts up, depending on the actual device memory).
      "SK_DEFAULT_FONT_CACHE_LIMIT=1048576",  # 1024 * 1024
    ]
  } else {
    defines += [ "SK_DEFAULT_FONT_CACHE_LIMIT=20971520" ]  # 20 * 1024 * 1024
  }

  if (is_win) {
    defines += [
      # On windows, GDI handles are a scarse system-wide resource so we have to
      # keep the glyph cache, which holds up to 4 GDI handles per entry, to a
      # fairly small size. http://crbug.com/314387
      "SK_DEFAULT_FONT_CACHE_COUNT_LIMIT=256",
    ]

    cflags = [
      "/wd4244",  # conversion from 'type1( __int64)' to 'type2 (unsigned int)'
      "/wd4341",  # signed value is out of range for enum constant.
      "/wd4345",  # Object is default-initialized if initialization is omitted.
      "/wd4390",  # ';'empty statement found in looping;is it what was intended?
      "/wd4554",  # 'operator' : check operator precedence for possible error
      "/wd4748",  # compiler will disable optimizations if a function has inline
                  # assembly code contains flow control(jmp or jcc) statements.

      "/wd4800",  # forcing value to bool 'true/false'(assigning int to bool).
      "/wd5041",  # out-of-line definition for constexpr static data member is
                  # not needed and is deprecated in C++17
    ]
  }
}

source_set("skcms") {
  cflags = []
  if (!is_win || is_clang) {
    cflags += [
      "-w",
      "-std=c11",
    ]
  }

  # LLVM automatically sets the equivalent of GCC's -mfp16-format=ieee on ARM
  # builds by default, while GCC itself does not. We need it to enable support
  # for half-precision floating point data types used by SKCMS on ARM.
  if ((is_linux || is_chromeos) && !is_clang && current_cpu == "arm") {
    cflags += [ "-mfp16-format=ieee" ]
  }

  public =
      rebase_path(skcms_public_headers, ".", "//third_party/skia/modules/skcms")
  sources = rebase_path(skcms_sources, ".", "//third_party/skia/modules/skcms")
}

component("skia") {
  sources = [
    # PDFium sources.
    "config/SkPdfiumUserConfig.h",
    "ext/google_logging.cc",
  ]

  # The skia sources values are relative to the skia_dir, so we need to rebase.
  sources += skia_core_public
  sources += skia_sksl_gpu_sources
  sources += skia_sksl_sources
  sources += skia_utils_sources
  sources += [
    "//third_party/skia/src/codec/SkBmpBaseCodec.cpp",
    "//third_party/skia/src/codec/SkBmpCodec.cpp",
    "//third_party/skia/src/codec/SkBmpMaskCodec.cpp",
    "//third_party/skia/src/codec/SkBmpRLECodec.cpp",
    "//third_party/skia/src/codec/SkBmpStandardCodec.cpp",
    "//third_party/skia/src/codec/SkCodec.cpp",
    "//third_party/skia/src/codec/SkCodecImageGenerator.cpp",
    "//third_party/skia/src/codec/SkColorTable.cpp",
    "//third_party/skia/src/codec/SkMaskSwizzler.cpp",
    "//third_party/skia/src/codec/SkMasks.cpp",
    "//third_party/skia/src/codec/SkSampler.cpp",
    "//third_party/skia/src/codec/SkSwizzler.cpp",
    "//third_party/skia/src/codec/SkWbmpCodec.cpp",
    "//third_party/skia/src/fonts/SkFontMgr_indirect.cpp",
    "//third_party/skia/src/fonts/SkRemotableFontMgr.cpp",
    "//third_party/skia/src/images/SkImageEncoder.cpp",
    "//third_party/skia/src/images/SkPngEncoder.cpp",
    "//third_party/skia/src/ports/SkGlobalInitialization_default.cpp",
    "//third_party/skia/src/ports/SkImageGenerator_none.cpp",
    "//third_party/skia/src/ports/SkOSFile_stdio.cpp",
    "//third_party/skia/src/sfnt/SkOTTable_name.cpp",
    "//third_party/skia/src/sfnt/SkOTUtils.cpp",

    #pdfium
    "//third_party/skia/src/ports/SkDiscardableMemory_none.cpp",
    "//third_party/skia/src/ports/SkMemory_malloc.cpp",
  ]

  # This and skia_opts are really the same conceptual target so share headers.
  allow_circular_includes_from = [ ":skia_opts" ]

  if (current_cpu == "arm") {
    sources += [ "//third_party/skia/src/core/SkUtilsArm.cpp" ]
  }

  # GPU
  if (skia_support_gpu) {
    sources += skia_gpu_sources
    sources += skia_null_gpu_sources
    sources += skia_shared_gpu_sources
    if (skia_use_gl) {
      sources += skia_gl_gpu_sources
    }
  }

  # Remove unused util files include in utils.gni
  sources -= [
    "//third_party/skia/src/utils/SkCamera.cpp",
    "//third_party/skia/src/utils/SkParsePath.cpp",
  ]

  # need separate win section to handle chromes auto gn filter
  # (build/config/BUILDCONFIG.gn)
  if (is_win) {
    sources -= [
      #windows
      "//third_party/skia/src/utils/win/SkAutoCoInitialize.cpp",
      "//third_party/skia/src/utils/win/SkIStream.cpp",
      "//third_party/skia/src/utils/win/SkWGL_win.cpp",
    ]
  }

  # Select Skia ports.

  # FreeType is needed everywhere (except on iOS), on Linux and Android as main
  # font backend, on Windows and Mac as fallback backend for Variations.
  if (!is_ios) {
    sources += [
      "//third_party/skia/src/ports/SkFontHost_FreeType.cpp",
      "//third_party/skia/src/ports/SkFontHost_FreeType_common.cpp",
    ]
  }

  if (is_win) {
    sources += [
      "//third_party/skia/src/ports/SkFontHost_win.cpp",

      # TODO(crbug.com/pdfium/1830)  Consider using SkFontMgr_win_dw_factory
      # instead of SkFontMgr_custom_empty (which is what the embedder test
      # hashes are based upon).
      "//third_party/skia/src/ports/SkFontMgr_custom.cpp",
      "//third_party/skia/src/ports/SkFontMgr_custom_empty.cpp",
      "//third_party/skia/src/ports/SkFontMgr_custom_empty_factory.cpp",
      "//third_party/skia/src/ports/SkFontMgr_win_dw.cpp",
      "//third_party/skia/src/ports/SkOSFile_win.cpp",
      "//third_party/skia/src/ports/SkRemotableFontMgr_win_dw.cpp",
      "//third_party/skia/src/ports/SkScalerContext_win_dw.cpp",
      "//third_party/skia/src/ports/SkTypeface_win_dw.cpp",
    ]
  } else {
    sources += [ "//third_party/skia/src/ports/SkOSFile_posix.cpp" ]
  }

  frameworks = []
  if (is_apple) {
    sources += [
      # TODO(crbug.com/pdfium/1830)  Consider using SkFontMgr_mac_ct instead of
      # SkFontMgr_custom_empty (which is what the embedder test hashes are
      # based upon).
      "//third_party/skia/src/ports/SkFontMgr_custom.cpp",
      "//third_party/skia/src/ports/SkFontMgr_custom_empty.cpp",
      "//third_party/skia/src/ports/SkFontMgr_custom_empty_factory.cpp",
      "//third_party/skia/src/ports/SkScalerContext_mac_ct.cpp",
      "//third_party/skia/src/ports/SkScalerContext_mac_ct.h",
      "//third_party/skia/src/ports/SkTypeface_mac_ct.cpp",
      "//third_party/skia/src/ports/SkTypeface_mac_ct.h",
    ]
    frameworks += [
      "CoreFoundation.framework",
      "CoreGraphics.framework",
      "CoreText.framework",
    ]
  }

  if (is_linux || is_chromeos) {
    sources += [
      "//third_party/skia/src/ports/SkFontConfigInterface.cpp",
      "//third_party/skia/src/ports/SkFontConfigInterface_direct.cpp",
      "//third_party/skia/src/ports/SkFontConfigInterface_direct_factory.cpp",
      "//third_party/skia/src/ports/SkFontMgr_FontConfigInterface.cpp",
      "//third_party/skia/src/ports/SkFontMgr_custom.cpp",
      "//third_party/skia/src/ports/SkFontMgr_custom_empty.cpp",
      "//third_party/skia/src/ports/SkFontMgr_custom_empty_factory.cpp",
    ]
  }

  if (is_android) {
    sources += [
      # Unlike Chromium, standalone PDFium on Linux and Chrome OS does not
      # require these files, since PDFium does not perform Android emulation.
      # Note that this requires expat.
      "//third_party/skia/src/ports/SkFontMgr_android.cpp",
      "//third_party/skia/src/ports/SkFontMgr_android_factory.cpp",
      "//third_party/skia/src/ports/SkFontMgr_android_parser.cpp",
    ]
  }

  if (is_clang && !is_nacl) {
    # Skia won't compile with some of the more strict clang warnings.
    # e.g. it does:
    #  SkASSERT(!"sk_out_of_memory");
    configs -= [ "//build/config/clang:extra_warnings" ]
  }

  configs -= [ "//build/config/compiler:chromium_code" ]
  configs += [
    ":skia_config",
    ":skia_library_config",
    "//build/config/compiler:no_chromium_code",
  ]
  public_configs = [ ":skia_config" ]

  deps = [
    ":skcms",
    ":skia_opts",
    "../third_party:png",
    "../third_party:zlib",
    "//:freetype_common",
  ]
  public_deps = [ ":skia_core_and_effects" ]

  if (is_linux || is_chromeos) {
    deps += [
      "//third_party:fontconfig",
      "//third_party/icu:icuuc",
    ]
  }

  if (is_android) {
    deps += [
      "//third_party/android_ndk:cpu_features",
      "//third_party/expat",
    ]
  }

  if (is_android && !is_debug) {
    configs -= [ "//build/config/compiler:default_optimization" ]
    configs += [ "//build/config/compiler:optimize_max" ]
  }

  if (is_ios) {
    frameworks += [ "ImageIO.framework" ]
    sources += [ "//third_party/skia/src/utils/mac/SkCreateCGImageRef.cpp" ]
  }

  if (skia_support_pdf) {
    deps += [ "//third_party/sfntly" ]
    sources += skia_pdf_sources
  } else {
    sources += [ "//third_party/skia/src/pdf/SkDocument_PDF_None.cpp" ]
  }
}

# Template for things that are logically part of :skia, but need to be split out
# so custom compile flags can be applied.
#
# These are all opted out of check_includes, due to (logically) being part of
# skia.
template("skia_source_set") {
  source_set(target_name) {
    forward_variables_from(invoker, "*")

    check_includes = false

    if (!is_debug) {
      configs -= [ "//build/config/compiler:default_optimization" ]
      configs += [ "//build/config/compiler:optimize_max" ]
    }

    configs -= [ "//build/config/compiler:chromium_code" ]
    configs += [
      ":skia_config",
      ":skia_library_config",
      "//build/config/compiler:no_chromium_code",
    ]
    public_configs = [ ":skia_config" ]

    if (is_win) {
      cflags_cc = [
        "/std:c++17",
        "/wd5041",  # out-of-line definition for constexpr static data member is
                    # not needed and is deprecated in C++17
      ]
    } else {
      cflags_cc = [ "-std=c++17" ]
    }
  }
}

skia_source_set("skia_core_and_effects") {
  defines = []
  sources = skia_core_sources
  sources += skia_effects_sources
  sources += skia_effects_imagefilter_sources

  visibility = [ ":skia" ]
}

# Bits that involve special vector-y hardware.
if (current_cpu == "arm64") {
  skia_source_set("skia_opts_crc32") {
    sources = skia_opts.crc32_sources
    cflags = [ "-march=armv8-a+crc" ]
    visibility = [ ":skia_opts" ]
  }
}
if (current_cpu == "x86" || current_cpu == "x64") {
  skia_source_set("skia_opts_sse3") {
    sources = skia_opts.ssse3_sources
    if (!is_win || is_clang) {
      cflags = [ "-mssse3" ]
    }
    if (is_win) {
      defines = [ "SK_CPU_SSE_LEVEL=31" ]
    }
    visibility = [ ":skia_opts" ]
  }
  skia_source_set("skia_opts_sse42") {
    sources = skia_opts.sse42_sources
    if (!is_win || is_clang) {
      cflags = [ "-msse4.2" ]
    }
    if (is_win) {
      defines = [ "SK_CPU_SSE_LEVEL=42" ]
    }
    visibility = [ ":skia_opts" ]
  }
  skia_source_set("skia_opts_avx") {
    sources = skia_opts.avx_sources
    if (!is_win) {
      cflags = [ "-mavx" ]
    }
    if (is_win) {
      cflags = [ "/arch:AVX" ]
    }
    visibility = [ ":skia_opts" ]
  }
  skia_source_set("skia_opts_hsw") {
    sources = skia_opts.hsw_sources
    if (!is_win) {
      cflags = [
        "-mavx2",
        "-mbmi",
        "-mbmi2",
        "-mf16c",
        "-mfma",
      ]
    }
    if (is_win) {
      cflags = [ "/arch:AVX2" ]
    }
    visibility = [ ":skia_opts" ]
  }
  skia_source_set("skia_opts_skx") {
    sources = skia_opts.skx_sources
    if (!is_win) {
      cflags = [ "-march=skylake-avx512" ]
    }
    if (is_win) {
      cflags = [ "/arch:AVX512" ]
    }
    visibility = [ ":skia_opts" ]
  }
}

skia_source_set("skia_opts") {
  cflags = []
  defines = []

  if (current_cpu == "x86" || current_cpu == "x64") {
    deps = [
      ":skia_opts_avx",
      ":skia_opts_hsw",
      ":skia_opts_skx",
      ":skia_opts_sse3",
      ":skia_opts_sse42",
    ]
  } else if (current_cpu == "arm") {
    # The assembly uses the frame pointer register (r7 in Thumb/r11 in
    # ARM), the compiler doesn't like that.
    cflags += [ "-fomit-frame-pointer" ]

    if (arm_version >= 7) {
      if (arm_use_neon || arm_optionally_use_neon) {
        # Root build config sets -mfpu=$arm_fpu, which we expect to be neon
        # when running this.
        if (!arm_use_neon) {
          configs -= [ "//build/config/compiler:compiler_arm_fpu" ]
          cflags += [ "-mfpu=neon" ]
        }
      }
    }
  } else if (current_cpu == "arm64") {
    deps = [ ":skia_opts_crc32" ]
  } else if (current_cpu == "mipsel" || current_cpu == "mips64el") {
    cflags += [ "-fomit-frame-pointer" ]
  } else {
    assert(false, "Unsupported target CPU " + current_cpu)
  }

  if (is_android && !is_debug) {
    configs -= [ "//build/config/compiler:default_optimization" ]
    configs += [ "//build/config/compiler:optimize_max" ]
  }

  visibility = [ ":skia" ]
}