win8/metro_driver/ime/text_store.h

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef WIN8_METRO_DRIVER_IME_TEXT_STORE_H_
   6 #define WIN8_METRO_DRIVER_IME_TEXT_STORE_H_
   7
   8 #include <atlbase.h>
   9 #include <atlcom.h>
  10 #include <initguid.h>
  11 #include <inputscope.h>
  12 #include <msctf.h>
  13
  14 #include <deque>
  15 #include <vector>
  16
  17 #include "base/basictypes.h"
  18 #include "base/compiler_specific.h"
  19 #include "base/memory/ref_counted.h"
  20 #include "base/strings/string16.h"
  21 #include "base/win/scoped_comptr.h"
  22 #include "ui/metro_viewer/ime_types.h"
  23
  24 namespace metro_driver {
  25
  26 class TextStoreDelegate;
  27
  28 // TextStore is used to interact with the input method via TSF manager.
  29 // TextStore have a string buffer which is manipulated by TSF manager through
  30 // ITextStoreACP interface methods such as SetText().
  31 // When the input method updates the composition, TextStore calls
  32 // TextInputClient::SetCompositionText(). And when the input method finishes the
  33 // composition, TextStore calls TextInputClient::InsertText() and clears the
  34 // buffer.
  35 //
  36 // How TextStore works:
  37 //  - The user enters "a".
  38 //    - The input method set composition as "a".
  39 //    - TSF manager calls TextStore::RequestLock().
  40 //    - TextStore callbacks ITextStoreACPSink::OnLockGranted().
  41 //    - In OnLockGranted(), TSF manager calls
  42 //      - TextStore::OnStartComposition()
  43 //      - TextStore::SetText()
  44 //        The string buffer is set as "a".
  45 //      - TextStore::OnUpdateComposition()
  46 //      - TextStore::OnEndEdit()
  47 //        TextStore can get the composition information such as underlines.
  48 //   - TextStore calls TextInputClient::SetCompositionText().
  49 //     "a" is shown with an underline as composition string.
  50 // - The user enters <space>.
  51 //    - The input method set composition as "A".
  52 //    - TSF manager calls TextStore::RequestLock().
  53 //    - TextStore callbacks ITextStoreACPSink::OnLockGranted().
  54 //    - In OnLockGranted(), TSF manager calls
  55 //      - TextStore::SetText()
  56 //        The string buffer is set as "A".
  57 //      - TextStore::OnUpdateComposition()
  58 //      - TextStore::OnEndEdit()
  59 //   - TextStore calls TextInputClient::SetCompositionText().
  60 //     "A" is shown with an underline as composition string.
  61 // - The user enters <enter>.
  62 //    - The input method commits "A".
  63 //    - TSF manager calls TextStore::RequestLock().
  64 //    - TextStore callbacks ITextStoreACPSink::OnLockGranted().
  65 //    - In OnLockGranted(), TSF manager calls
  66 //      - TextStore::OnEndComposition()
  67 //      - TextStore::OnEndEdit()
  68 //        TextStore knows "A" is committed.
  69 //   - TextStore calls TextInputClient::InsertText().
  70 //     "A" is shown as committed string.
  71 //   - TextStore clears the string buffer.
  72 //   - TextStore calls OnSelectionChange(), OnLayoutChange() and
  73 //     OnTextChange() of ITextStoreACPSink to let TSF manager know that the
  74 //     string buffer has been changed.
  75 //
  76 // About the locking scheme:
  77 // When TSF manager manipulates the string buffer it calls RequestLock() to get
  78 // the lock of the document. If TextStore can grant the lock request, it
  79 // callbacks ITextStoreACPSink::OnLockGranted().
  80 // RequestLock() is called from only one thread, but called recursively in
  81 // OnLockGranted() or OnSelectionChange() or OnLayoutChange() or OnTextChange().
  82 // If the document is locked and the lock request is asynchronous, TextStore
  83 // queues the request. The queued requests will be handled after the current
  84 // lock is removed.
  85 // More information about document locks can be found here:
  86 //   http://msdn.microsoft.com/en-us/library/ms538064
  87 //
  88 // More information about TSF can be found here:
  89 //   http://msdn.microsoft.com/en-us/library/ms629032
  90 class ATL_NO_VTABLE TextStore
  91     : public CComObjectRootEx<CComMultiThreadModel>,
  92       public ITextStoreACP,
  93       public ITfContextOwnerCompositionSink,
  94       public ITfTextEditSink {
  95  public:
  96   virtual ~TextStore();
  97
  98   BEGIN_COM_MAP(TextStore)
  99     COM_INTERFACE_ENTRY(ITextStoreACP)
 100     COM_INTERFACE_ENTRY(ITfContextOwnerCompositionSink)
 101     COM_INTERFACE_ENTRY(ITfTextEditSink)
 102   END_COM_MAP()
 103
 104   // ITextStoreACP:
 105   STDMETHOD(AdviseSink)(REFIID iid, IUnknown* unknown, DWORD mask) override;
 106   STDMETHOD(FindNextAttrTransition)(LONG acp_start,
 107                                     LONG acp_halt,
 108                                     ULONG num_filter_attributes,
 109                                     const TS_ATTRID* filter_attributes,
 110                                     DWORD flags,
 111                                     LONG* acp_next,
 112                                     BOOL* found,
 113                                     LONG* found_offset) override;
 114   STDMETHOD(GetACPFromPoint)(TsViewCookie view_cookie,
 115                              const POINT* point,
 116                              DWORD flags,
 117                              LONG* acp) override;
 118   STDMETHOD(GetActiveView)(TsViewCookie* view_cookie) override;
 119   STDMETHOD(GetEmbedded)(LONG acp_pos,
 120                          REFGUID service,
 121                          REFIID iid,
 122                          IUnknown** unknown) override;
 123   STDMETHOD(GetEndACP)(LONG* acp) override;
 124   STDMETHOD(GetFormattedText)(LONG acp_start,
 125                               LONG acp_end,
 126                               IDataObject** data_object) override;
 127   STDMETHOD(GetScreenExt)(TsViewCookie view_cookie, RECT* rect) override;
 128   STDMETHOD(GetSelection)(ULONG selection_index,
 129                           ULONG selection_buffer_size,
 130                           TS_SELECTION_ACP* selection_buffer,
 131                           ULONG* fetched_count) override;
 132   STDMETHOD(GetStatus)(TS_STATUS* pdcs) override;
 133   STDMETHOD(GetText)(LONG acp_start,
 134                      LONG acp_end,
 135                      wchar_t* text_buffer,
 136                      ULONG text_buffer_size,
 137                      ULONG* text_buffer_copied,
 138                      TS_RUNINFO* run_info_buffer,
 139                      ULONG run_info_buffer_size,
 140                      ULONG* run_info_buffer_copied,
 141                      LONG* next_acp) override;
 142   STDMETHOD(GetTextExt)(TsViewCookie view_cookie,
 143                         LONG acp_start,
 144                         LONG acp_end,
 145                         RECT* rect,
 146                         BOOL* clipped) override;
 147   STDMETHOD(GetWnd)(TsViewCookie view_cookie, HWND* window_handle) override;
 148   STDMETHOD(InsertEmbedded)(DWORD flags,
 149                             LONG acp_start,
 150                             LONG acp_end,
 151                             IDataObject* data_object,
 152                             TS_TEXTCHANGE* change) override;
 153   STDMETHOD(InsertEmbeddedAtSelection)(DWORD flags,
 154                                        IDataObject* data_object,
 155                                        LONG* acp_start,
 156                                        LONG* acp_end,
 157                                        TS_TEXTCHANGE* change) override;
 158   STDMETHOD(InsertTextAtSelection)(DWORD flags,
 159                                    const wchar_t* text_buffer,
 160                                    ULONG text_buffer_size,
 161                                    LONG* acp_start,
 162                                    LONG* acp_end,
 163                                    TS_TEXTCHANGE* text_change) override;
 164   STDMETHOD(QueryInsert)(LONG acp_test_start,
 165                          LONG acp_test_end,
 166                          ULONG text_size,
 167                          LONG* acp_result_start,
 168                          LONG* acp_result_end) override;
 169   STDMETHOD(QueryInsertEmbedded)(const GUID* service,
 170                                  const FORMATETC* format,
 171                                  BOOL* insertable) override;
 172   STDMETHOD(RequestAttrsAtPosition)(LONG acp_pos,
 173                                     ULONG attribute_buffer_size,
 174                                     const TS_ATTRID* attribute_buffer,
 175                                     DWORD flags) override;
 176   STDMETHOD(RequestAttrsTransitioningAtPosition)(
 177       LONG acp_pos,
 178       ULONG attribute_buffer_size,
 179       const TS_ATTRID* attribute_buffer,
 180       DWORD flags) override;
 181   STDMETHOD(RequestLock)(DWORD lock_flags, HRESULT* result) override;
 182   STDMETHOD(RequestSupportedAttrs)(DWORD flags,
 183                                    ULONG attribute_buffer_size,
 184                                    const TS_ATTRID* attribute_buffer) override;
 185   STDMETHOD(RetrieveRequestedAttrs)(ULONG attribute_buffer_size,
 186                                     TS_ATTRVAL* attribute_buffer,
 187                                     ULONG* attribute_buffer_copied) override;
 188   STDMETHOD(SetSelection)(ULONG selection_buffer_size,
 189                           const TS_SELECTION_ACP* selection_buffer) override;
 190   STDMETHOD(SetText)(DWORD flags,
 191                      LONG acp_start,
 192                      LONG acp_end,
 193                      const wchar_t* text_buffer,
 194                      ULONG text_buffer_size,
 195                      TS_TEXTCHANGE* text_change) override;
 196   STDMETHOD(UnadviseSink)(IUnknown* unknown) override;
 197
 198   // ITfContextOwnerCompositionSink:
 199   STDMETHOD(OnStartComposition)(ITfCompositionView* composition_view,
 200                                 BOOL* ok) override;
 201   STDMETHOD(OnUpdateComposition)(ITfCompositionView* composition_view,
 202                                  ITfRange* range) override;
 203   STDMETHOD(OnEndComposition)(ITfCompositionView* composition_view) override;
 204
 205   // ITfTextEditSink:
 206   STDMETHOD(OnEndEdit)(ITfContext* context, TfEditCookie read_only_edit_cookie,
 207                        ITfEditRecord* edit_record) override;
 208
 209   // Cancels the ongoing composition if exists.
 210   bool CancelComposition();
 211
 212   // Confirms the ongoing composition if exists.
 213   bool ConfirmComposition();
 214
 215   // Sends OnLayoutChange() via |text_store_acp_sink_|.
 216   void SendOnLayoutChange();
 217
 218   // Creates an instance of TextStore. Returns NULL if fails.
 219   static scoped_refptr<TextStore> Create(
 220       HWND window_handle,
 221       const std::vector<InputScope>& input_scopes,
 222       TextStoreDelegate* delegate);
 223
 224  private:
 225   friend CComObject<TextStore>;
 226   TextStore();
 227
 228   void Initialize(HWND window_handle,
 229                   ITfCategoryMgr* category_manager,
 230                   ITfDisplayAttributeMgr* display_attribute_manager,
 231                   ITfInputScope* input_scope,
 232                   TextStoreDelegate* delegate);
 233
 234   // Checks if the document has a read-only lock.
 235   bool HasReadLock() const;
 236
 237   // Checks if the document has a read and write lock.
 238   bool HasReadWriteLock() const;
 239
 240   // Gets the display attribute structure.
 241   bool GetDisplayAttribute(TfGuidAtom guid_atom,
 242                            TF_DISPLAYATTRIBUTE* attribute);
 243
 244   // Gets the committed string size and underline information of the context.
 245   bool GetCompositionStatus(
 246       ITfContext* context,
 247       const TfEditCookie read_only_edit_cookie,
 248       uint32* committed_size,
 249       std::vector<metro_viewer::UnderlineInfo>* undelines);
 250
 251   // A pointer of ITextStoreACPSink, this instance is given in AdviseSink.
 252   base::win::ScopedComPtr<ITextStoreACPSink> text_store_acp_sink_;
 253
 254   // The current mask of |text_store_acp_sink_|.
 255   DWORD text_store_acp_sink_mask_;
 256
 257   // HWND of the attached window.
 258   HWND window_handle_;
 259
 260   //  |string_buffer_| contains committed string and composition string.
 261   //  Example: "aoi" is committed, and "umi" is under composition.
 262   //    |string_buffer_|: "aoiumi"
 263   //    |committed_size_|: 3
 264   base::string16 string_buffer_;
 265   uint32 committed_size_;
 266
 267   //  |selection_start_| and |selection_end_| indicates the selection range.
 268   //  Example: "iue" is selected
 269   //    |string_buffer_|: "aiueo"
 270   //    |selection_start_|: 1
 271   //    |selection_end_|: 4
 272   uint32 selection_start_;
 273   uint32 selection_end_;
 274
 275   //  |start_offset| and |end_offset| of |composition_undelines_| indicates
 276   //  the offsets in |string_buffer_|.
 277   //  Example: "aoi" is committed. There are two underlines in "umi" and "no".
 278   //    |string_buffer_|: "aoiumino"
 279   //    |committed_size_|: 3
 280   //    underlines_[0].start_offset: 3
 281   //    underlines_[0].end_offset: 6
 282   //    underlines_[1].start_offset: 6
 283   //    underlines_[1].end_offset: 8
 284   std::vector<metro_viewer::UnderlineInfo> underlines_;
 285
 286   // |edit_flag_| indicates that the status is edited during
 287   // ITextStoreACPSink::OnLockGranted().
 288   bool edit_flag_;
 289
 290   // The type of current lock.
 291   //   0: No lock.
 292   //   TS_LF_READ: read-only lock.
 293   //   TS_LF_READWRITE: read/write lock.
 294   DWORD current_lock_type_;
 295
 296   // Queue of the lock request used in RequestLock().
 297   std::deque<DWORD> lock_queue_;
 298
 299   // Category manager and Display attribute manager are used to obtain the
 300   // attributes of the composition string.
 301   base::win::ScopedComPtr<ITfCategoryMgr> category_manager_;
 302   base::win::ScopedComPtr<ITfDisplayAttributeMgr> display_attribute_manager_;
 303
 304   // Represents the context information of this text.
 305   base::win::ScopedComPtr<ITfInputScope> input_scope_;
 306
 307   // The delegate attached to this text store.
 308   TextStoreDelegate* delegate_;
 309
 310   DISALLOW_COPY_AND_ASSIGN(TextStore);
 311 };
 312
 313 }  // namespace metro_driver
 314
 315 #endif  // WIN8_METRO_DRIVER_IME_TEXT_STORE_H_