// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "content/renderer/renderer_font_platform_win.h"

#include <dwrite.h>
#include <string>
#include <vector>
#include <wrl/implements.h>
#include <wrl/wrappers/corewrappers.h>

#include "base/debug/alias.h"
#include "base/debug/crash_logging.h"
#include "base/files/file_enumerator.h"
#include "base/files/file_path.h"
#include "base/files/memory_mapped_file.h"
#include "base/memory/scoped_ptr.h"
#include "base/memory/scoped_vector.h"
#include "base/metrics/histogram.h"
#include "base/path_service.h"
#include "base/strings/utf_string_conversions.h"
#include "base/time/time.h"
#include "base/win/iat_patch_function.h"
#include "base/win/registry.h"
#include "base/win/scoped_comptr.h"

namespace {

namespace mswr = Microsoft::WRL;
namespace mswrw = Microsoft::WRL::Wrappers;

static const char kFontKeyName[] = "font_key_name";

class FontCollectionLoader
    : public mswr::RuntimeClass<mswr::RuntimeClassFlags<mswr::ClassicCom>,
                                IDWriteFontCollectionLoader> {
 public:
  // IDWriteFontCollectionLoader methods.
  virtual HRESULT STDMETHODCALLTYPE
      CreateEnumeratorFromKey(IDWriteFactory* factory,
                              void const* key,
                              UINT32 key_size,
                              IDWriteFontFileEnumerator** file_enumerator);

  static HRESULT Initialize(IDWriteFactory* factory);

  UINT32 GetFontMapSize();

  std::wstring GetFontNameFromKey(UINT32 idx);

  bool LoadFontListFromRegistry();
  bool LoadRestrictedFontList();

  FontCollectionLoader() {};
  virtual ~FontCollectionLoader() {};

 private:
  mswr::ComPtr<IDWriteFontFileLoader> file_loader_;

  std::vector<std::wstring> reg_fonts_;
};

mswr::ComPtr<FontCollectionLoader> g_font_loader;

class FontFileStream
    : public mswr::RuntimeClass<mswr::RuntimeClassFlags<mswr::ClassicCom>,
                                IDWriteFontFileStream> {
 public:
  // IDWriteFontFileStream methods.
  virtual HRESULT STDMETHODCALLTYPE
  ReadFileFragment(void const** fragment_start,
                   UINT64 file_offset,
                   UINT64 fragment_size,
                   void** context) {
    if (!memory_.get() || !memory_->IsValid() ||
        file_offset >= memory_->length() ||
        (file_offset + fragment_size) > memory_->length())
      return E_FAIL;

    *fragment_start = static_cast<BYTE const*>(memory_->data()) +
                      static_cast<size_t>(file_offset);
    *context = NULL;
    return S_OK;
  }

  virtual void STDMETHODCALLTYPE ReleaseFileFragment(void* context) {}

  virtual HRESULT STDMETHODCALLTYPE GetFileSize(UINT64* file_size) {
    if (!memory_.get() || !memory_->IsValid())
      return E_FAIL;

    *file_size = memory_->length();
    return S_OK;
  }

  virtual HRESULT STDMETHODCALLTYPE GetLastWriteTime(UINT64* last_write_time) {
    if (!memory_.get() || !memory_->IsValid())
      return E_FAIL;

    // According to MSDN article http://goo.gl/rrSYzi the "last modified time"
    // is used by DirectWrite font selection algorithms to determine whether
    // one font resource is more up to date than another one.
    // So by returning 0 we are assuming that it will treat all fonts to be
    // equally up to date.
    // TODO(shrikant): We should further investigate this.
    *last_write_time = 0;
    return S_OK;
  }

  FontFileStream::FontFileStream() : font_key_(0) {
  };

  HRESULT RuntimeClassInitialize(UINT32 font_key) {
    base::FilePath path;
    PathService::Get(base::DIR_WINDOWS_FONTS, &path);
    std::wstring font_key_name(g_font_loader->GetFontNameFromKey(font_key));
    path = path.Append(font_key_name.c_str());
    memory_.reset(new base::MemoryMappedFile());

    // Put some debug information on stack.
    WCHAR font_name[256];
    path.value().copy(font_name, arraysize(font_name));
    base::debug::Alias(font_name);

    if (!memory_->Initialize(path)) {
      memory_.reset();
      return E_FAIL;
    }

    font_key_ = font_key;

    base::debug::SetCrashKeyValue(kFontKeyName,
                                  base::WideToUTF8(font_key_name));
    return S_OK;
  }

  virtual ~FontFileStream() {}

  UINT32 font_key_;
  scoped_ptr<base::MemoryMappedFile> memory_;
};

class FontFileLoader
    : public mswr::RuntimeClass<mswr::RuntimeClassFlags<mswr::ClassicCom>,
                                IDWriteFontFileLoader> {
 public:
  // IDWriteFontFileLoader methods.
  virtual HRESULT STDMETHODCALLTYPE
  CreateStreamFromKey(void const* ref_key,
                      UINT32 ref_key_size,
                      IDWriteFontFileStream** stream) {
    if (ref_key_size != sizeof(UINT32))
      return E_FAIL;

    UINT32 font_key = *static_cast<const UINT32*>(ref_key);
    mswr::ComPtr<FontFileStream> font_stream;
    HRESULT hr = mswr::MakeAndInitialize<FontFileStream>(&font_stream,
                                                         font_key);
    if (SUCCEEDED(hr)) {
      *stream = font_stream.Detach();
      return S_OK;
    }
    return E_FAIL;
  }

  FontFileLoader() {}
  virtual ~FontFileLoader() {}
};

class FontFileEnumerator
    : public mswr::RuntimeClass<mswr::RuntimeClassFlags<mswr::ClassicCom>,
                                IDWriteFontFileEnumerator> {
 public:
  // IDWriteFontFileEnumerator methods.
  virtual HRESULT STDMETHODCALLTYPE MoveNext(BOOL* has_current_file) {
    *has_current_file = FALSE;

    if (current_file_)
      current_file_.ReleaseAndGetAddressOf();

    if (font_idx_ < g_font_loader->GetFontMapSize()) {
      HRESULT hr =
          factory_->CreateCustomFontFileReference(&font_idx_,
                                                  sizeof(UINT32),
                                                  file_loader_.Get(),
                                                  current_file_.GetAddressOf());
      DCHECK(SUCCEEDED(hr));
      *has_current_file = TRUE;
      font_idx_++;
    }
    return S_OK;
  }

  virtual HRESULT STDMETHODCALLTYPE
  GetCurrentFontFile(IDWriteFontFile** font_file) {
    if (!current_file_) {
      *font_file = NULL;
      return E_FAIL;
    }

    *font_file = current_file_.Detach();
    return S_OK;
  }

  FontFileEnumerator(const void* keys,
                     UINT32 buffer_size,
                     IDWriteFactory* factory,
                     IDWriteFontFileLoader* file_loader)
      : factory_(factory), file_loader_(file_loader), font_idx_(0) {}

  virtual ~FontFileEnumerator() {}

  mswr::ComPtr<IDWriteFactory> factory_;
  mswr::ComPtr<IDWriteFontFile> current_file_;
  mswr::ComPtr<IDWriteFontFileLoader> file_loader_;
  UINT32 font_idx_;
};

// IDWriteFontCollectionLoader methods.
HRESULT STDMETHODCALLTYPE FontCollectionLoader::CreateEnumeratorFromKey(
    IDWriteFactory* factory,
    void const* key,
    UINT32 key_size,
    IDWriteFontFileEnumerator** file_enumerator) {
  *file_enumerator = mswr::Make<FontFileEnumerator>(
                         key, key_size, factory, file_loader_.Get()).Detach();
  return S_OK;
}

// static
HRESULT FontCollectionLoader::Initialize(IDWriteFactory* factory) {
  DCHECK(g_font_loader == NULL);

  g_font_loader = mswr::Make<FontCollectionLoader>();
  if (!g_font_loader) {
    DCHECK(FALSE);
    return E_FAIL;
  }

  CHECK(g_font_loader->LoadFontListFromRegistry());

  g_font_loader->file_loader_ = mswr::Make<FontFileLoader>().Detach();

  factory->RegisterFontFileLoader(g_font_loader->file_loader_.Get());
  factory->RegisterFontCollectionLoader(g_font_loader.Get());

  return S_OK;
}

UINT32 FontCollectionLoader::GetFontMapSize() {
  return reg_fonts_.size();
}

std::wstring FontCollectionLoader::GetFontNameFromKey(UINT32 idx) {
  DCHECK(idx < reg_fonts_.size());
  return reg_fonts_[idx];
}

bool FontCollectionLoader::LoadFontListFromRegistry() {
  const wchar_t kFontsRegistry[] =
      L"Software\\Microsoft\\Windows NT\\CurrentVersion\\Fonts";
  CHECK(reg_fonts_.empty());
  base::win::RegKey regkey;
  if (regkey.Open(HKEY_LOCAL_MACHINE, kFontsRegistry, KEY_READ) !=
      ERROR_SUCCESS) {
    return false;
  }

  base::FilePath system_font_path;
  PathService::Get(base::DIR_WINDOWS_FONTS, &system_font_path);

  std::wstring name;
  std::wstring value;
  for (DWORD idx = 0; idx < regkey.GetValueCount(); idx++) {
    if (regkey.GetValueNameAt(idx, &name) == ERROR_SUCCESS &&
        regkey.ReadValue(name.c_str(), &value) == ERROR_SUCCESS) {
      base::FilePath path(value.c_str());
      // We need to check if file name is the only component that exists,
      // we will ignore all other registry entries.
      std::vector<base::FilePath::StringType> components;
      path.GetComponents(&components);
      if (components.size() == 1 ||
          base::FilePath::CompareEqualIgnoreCase(system_font_path.value(),
                                                 path.DirName().value())) {
        reg_fonts_.push_back(path.BaseName().value());
      }
    }
  }
  UMA_HISTOGRAM_COUNTS("DirectWrite.Fonts.Loaded", reg_fonts_.size());
  UMA_HISTOGRAM_COUNTS("DirectWrite.Fonts.Ignored",
                       regkey.GetValueCount() - reg_fonts_.size());
  return true;
}

// This list is mainly based on prefs/prefs_tab_helper.cc kFontDefaults.
const wchar_t* kRestrictedFontSet[] = {
  // These are the "Web Safe" fonts.
  L"times.ttf",     // IDS_STANDARD_FONT_FAMILY
  L"timesbd.ttf",   // IDS_STANDARD_FONT_FAMILY
  L"timesbi.ttf",   // IDS_STANDARD_FONT_FAMILY
  L"timesi.ttf",    // IDS_STANDARD_FONT_FAMILY
  L"cour.ttf",      // IDS_FIXED_FONT_FAMILY
  L"courbd.ttf",    // IDS_FIXED_FONT_FAMILY
  L"courbi.ttf",    // IDS_FIXED_FONT_FAMILY
  L"couri.ttf",     // IDS_FIXED_FONT_FAMILY
  L"consola.ttf",   // IDS_FIXED_FONT_FAMILY_ALT_WIN
  L"consolab.ttf",  // IDS_FIXED_FONT_FAMILY_ALT_WIN
  L"consolai.ttf",  // IDS_FIXED_FONT_FAMILY_ALT_WIN
  L"consolaz.ttf",  // IDS_FIXED_FONT_FAMILY_ALT_WIN
  L"arial.ttf",     // IDS_SANS_SERIF_FONT_FAMILY
  L"arialbd.ttf",   // IDS_SANS_SERIF_FONT_FAMILY
  L"arialbi.ttf",   // IDS_SANS_SERIF_FONT_FAMILY
  L"ariali.ttf",    // IDS_SANS_SERIF_FONT_FAMILY
  L"comic.ttf",     // IDS_CURSIVE_FONT_FAMILY
  L"comicbd.ttf",   // IDS_CURSIVE_FONT_FAMILY
  L"comici.ttf",    // IDS_CURSIVE_FONT_FAMILY
  L"comicz.ttf",    // IDS_CURSIVE_FONT_FAMILY
  L"impact.ttf",    // IDS_FANTASY_FONT_FAMILY
  L"georgia.ttf",
  L"georgiab.ttf",
  L"georgiai.ttf",
  L"georgiaz.ttf",
  L"trebuc.ttf",
  L"trebucbd.ttf",
  L"trebucbi.ttf",
  L"trebucit.ttf",
  L"verdana.ttf",
  L"verdanab.ttf",
  L"verdanai.ttf",
  L"verdanaz.ttf",
  L"segoeui.ttf",   // IDS_PICTOGRAPH_FONT_FAMILY
  L"segoeuib.ttf",  // IDS_PICTOGRAPH_FONT_FAMILY
  L"segoeuii.ttf",  // IDS_PICTOGRAPH_FONT_FAMILY
  L"msgothic.ttc",  // IDS_STANDARD_FONT_FAMILY_JAPANESE
  L"msmincho.ttc",  // IDS_SERIF_FONT_FAMILY_JAPANESE
  L"gulim.ttc",     // IDS_FIXED_FONT_FAMILY_KOREAN
  L"batang.ttc",    // IDS_SERIF_FONT_FAMILY_KOREAN
  L"simsun.ttc",    // IDS_STANDARD_FONT_FAMILY_SIMPLIFIED_HAN
  L"mingliu.ttc",   // IDS_SERIF_FONT_FAMILY_TRADITIONAL_HAN

  // These are from the Blink fallback list.
  L"david.ttf",     // USCRIPT_HEBREW
  L"davidbd.ttf",   // USCRIPT_HEBREW
  L"euphemia.ttf",  // USCRIPT_CANADIAN_ABORIGINAL
  L"gautami.ttf",   // USCRIPT_TELUGU
  L"gautamib.ttf",  // USCRIPT_TELUGU
  L"latha.ttf",     // USCRIPT_TAMIL
  L"lathab.ttf",    // USCRIPT_TAMIL
  L"mangal.ttf",    // USCRIPT_DEVANAGARI
  L"mangalb.ttf",   // USCRIPT_DEVANAGARI
  L"monbaiti.ttf",  // USCRIPT_MONGOLIAN
  L"mvboli.ttf",    // USCRIPT_THAANA
  L"plantc.ttf",    // USCRIPT_CHEROKEE
  L"raavi.ttf",     // USCRIPT_GURMUKHI
  L"raavib.ttf",    // USCRIPT_GURMUKHI
  L"shruti.ttf",    // USCRIPT_GUJARATI
  L"shrutib.ttf",   // USCRIPT_GUJARATI
  L"sylfaen.ttf",   // USCRIPT_GEORGIAN and USCRIPT_ARMENIAN
  L"tahoma.ttf",    // USCRIPT_ARABIC,
  L"tahomabd.ttf",  // USCRIPT_ARABIC,
  L"tunga.ttf",     // USCRIPT_KANNADA
  L"tungab.ttf",    // USCRIPT_KANNADA
  L"vrinda.ttf",    // USCRIPT_BENGALI
  L"vrindab.ttf",   // USCRIPT_BENGALI
};

bool FontCollectionLoader::LoadRestrictedFontList() {
  reg_fonts_.clear();
  reg_fonts_.assign(kRestrictedFontSet,
                    kRestrictedFontSet + _countof(kRestrictedFontSet));
  return true;
}

}  // namespace

namespace content {

mswr::ComPtr<IDWriteFontCollection> g_font_collection;

IDWriteFontCollection* GetCustomFontCollection(IDWriteFactory* factory) {
  if (g_font_collection.Get() != NULL)
    return g_font_collection.Get();

  base::TimeTicks start_tick = base::TimeTicks::Now();

  FontCollectionLoader::Initialize(factory);

  // We try here to put arbitrary limit on max number of fonts that could
  // be loaded, otherwise we fallback to restricted set of fonts.
  const UINT32 kMaxFontThreshold = 1750;
  HRESULT hr = E_FAIL;
  if (g_font_loader->GetFontMapSize() < kMaxFontThreshold) {
    hr = factory->CreateCustomFontCollection(
        g_font_loader.Get(), NULL, 0, g_font_collection.GetAddressOf());
  }

  bool loadingRestricted = false;
  if (FAILED(hr) || !g_font_collection.Get()) {
    // We will try here just one more time with restricted font set.
    g_font_loader->LoadRestrictedFontList();
    hr = factory->CreateCustomFontCollection(
        g_font_loader.Get(), NULL, 0, g_font_collection.GetAddressOf());
  }

  base::TimeDelta time_delta = base::TimeTicks::Now() - start_tick;
  int64 delta = time_delta.ToInternalValue();
  base::debug::Alias(&delta);
  UINT32 size = g_font_loader->GetFontMapSize();
  base::debug::Alias(&size);
  base::debug::Alias(&loadingRestricted);

  CHECK(SUCCEEDED(hr));
  CHECK(g_font_collection.Get() != NULL);

  UMA_HISTOGRAM_TIMES("DirectWrite.Fonts.LoadTime", time_delta);

  base::debug::ClearCrashKey(kFontKeyName);

  return g_font_collection.Get();
}

}  // namespace content