browser/autocomplete/autocomplete_edit.h

// Copyright (c) 2011 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.

#ifndef CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_EDIT_H_
#define CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_EDIT_H_
#pragma once

#include "base/memory/scoped_ptr.h"
#include "base/string16.h"
#include "chrome/browser/autocomplete/autocomplete_controller_delegate.h"
#include "chrome/browser/autocomplete/autocomplete_match.h"
#include "chrome/common/instant_types.h"
#include "content/common/page_transition_types.h"
#include "googleurl/src/gurl.h"
#include "ui/gfx/native_widget_types.h"
#include "webkit/glue/window_open_disposition.h"

class AutocompleteController;
class AutocompleteEditController;
class AutocompleteEditModel;
class AutocompleteEditView;
class AutocompletePopupModel;
class AutocompleteResult;
class InstantController;
class Profile;
class SkBitmap;
class TabContentsWrapper;

namespace gfx {
class Rect;
}

// TODO(pkasting): The names and contents of the classes in
// this file are temporary.  I am in hack-and-slash mode right now.
// http://code.google.com/p/chromium/issues/detail?id=6772

// Embedders of an AutocompleteEdit widget must implement this class.
class AutocompleteEditController {
 public:
  // When the user presses enter or selects a line with the mouse, this
  // function will get called synchronously with the url to open and
  // disposition and transition to use when opening it.
  //
  // |alternate_nav_url|, if non-empty, contains the alternate navigation URL
  // for |url|, which the controller can check for existence.  See comments on
  // AutocompleteResult::GetAlternateNavURL().
  virtual void OnAutocompleteAccept(const GURL& url,
                                    WindowOpenDisposition disposition,
                                    PageTransition::Type transition,
                                    const GURL& alternate_nav_url) = 0;

  // Called when anything has changed that might affect the layout or contents
  // of the views around the edit, including the text of the edit and the
  // status of any keyword- or hint-related state.
  virtual void OnChanged() = 0;

  // Called when the selection of the AutocompleteEditView changes.
  virtual void OnSelectionBoundsChanged() = 0;

  // Called whenever the user starts or stops an input session (typing,
  // interacting with the edit, etc.).  When user input is not in progress,
  // the edit is guaranteed to be showing the permanent text.
  virtual void OnInputInProgress(bool in_progress) = 0;

  // Called whenever the autocomplete edit is losing focus.
  virtual void OnKillFocus() = 0;

  // Called whenever the autocomplete edit gets focused.
  virtual void OnSetFocus() = 0;

  // Returns the favicon of the current page.
  virtual SkBitmap GetFavicon() const = 0;

  // Returns the title of the current page.
  virtual string16 GetTitle() const = 0;

  // Returns the InstantController, or NULL if instant is not enabled.
  virtual InstantController* GetInstant() = 0;

  // Returns the TabContentsWrapper of the currently selected tab.
  virtual TabContentsWrapper* GetTabContentsWrapper() const = 0;

 protected:
  virtual ~AutocompleteEditController();
};

class AutocompleteEditModel : public AutocompleteControllerDelegate {
 public:
  struct State {
    State(bool user_input_in_progress,
          const string16& user_text,
          const string16& keyword,
          bool is_keyword_hint);
    ~State();

    bool user_input_in_progress;
    const string16 user_text;
    const string16 keyword;
    const bool is_keyword_hint;
  };

  AutocompleteEditModel(AutocompleteEditView* view,
                        AutocompleteEditController* controller,
                        Profile* profile);
  ~AutocompleteEditModel();

  AutocompleteController* autocomplete_controller() const {
    return autocomplete_controller_.get();
  }

  void set_popup_model(AutocompletePopupModel* popup_model) {
    popup_ = popup_model;
  }

  // TODO: The edit and popup should be siblings owned by the LocationBarView,
  // making this accessor unnecessary.
  AutocompletePopupModel* popup_model() const { return popup_; }

  // Invoked when the profile has changed.
  void SetProfile(Profile* profile);

  Profile* profile() const { return profile_; }

  // Returns the current state.  This assumes we are switching tabs, and changes
  // the internal state appropriately.
  const State GetStateForTabSwitch();

  // Restores local state from the saved |state|.
  void RestoreState(const State& state);

  // Returns the match for the current text. If the user has not edited the text
  // this is the match corresponding to the permanent text.
  AutocompleteMatch CurrentMatch();

  // Called when the user wants to export the entire current text as a URL.
  // Sets the url, and if known, the title and favicon.
  void GetDataForURLExport(GURL* url, string16* title, SkBitmap* favicon);

  // Returns true if a verbatim query should be used for instant. A verbatim
  // query is forced in certain situations, such as pressing delete at the end
  // of the edit.
  bool UseVerbatimInstant();

  // If the user presses ctrl-enter, it means "add .com to the the end".  The
  // desired TLD is the TLD the user desires to add to the end of the current
  // input, if any, based on their control key state and any other actions
  // they've taken.
  string16 GetDesiredTLD() const;

  // Returns true if the current edit contents will be treated as a
  // URL/navigation, as opposed to a search.
  bool CurrentTextIsURL() const;

  // Returns the match type for the current edit contents.
  AutocompleteMatch::Type CurrentTextType() const;

  // Invoked to adjust the text before writting to the clipboard for a copy
  // (e.g. by adding 'http' to the front). |sel_min| gives the minimum position
  // of the selection e.g. min(selection_start, selection_end). |text| is the
  // currently selected text. If |is_all_selected| is true all the text in the
  // edit is selected. If the url should be copied to the clipboard |write_url|
  // is set to true and |url| set to the url to write.
  void AdjustTextForCopy(int sel_min,
                         bool is_all_selected,
                         string16* text,
                         GURL* url,
                         bool* write_url);

  bool user_input_in_progress() const { return user_input_in_progress_; }

  // Sets the state of user_input_in_progress_, and notifies the observer if
  // that state has changed.
  void SetInputInProgress(bool in_progress);

  // Updates permanent_text_ to |new_permanent_text|.  Returns true if this
  // change should be immediately user-visible, because either the user is not
  // editing or the edit does not have focus.
  bool UpdatePermanentText(const string16& new_permanent_text);

  // Returns the URL corresponding to the permanent text.
  GURL PermanentURL();

  // Sets the user_text_ to |text|.  Only the View should call this.
  void SetUserText(const string16& text);

  // Calls through to SearchProvider::FinalizeInstantQuery.
  // If |skip_inline_autocomplete| is true then the |suggest_text| will be
  // turned into final text instead of inline autocomplete suggest.
  void FinalizeInstantQuery(const string16& input_text,
                            const string16& suggest_text,
                            bool skip_inline_autocomplete);

  // Sets the suggestion text.
  void SetSuggestedText(const string16& text,
                        InstantCompleteBehavior behavior);

  // Commits the suggested text. If |skip_inline_autocomplete| is true then the
  // suggested text will be committed as final text as if it's inputted by the
  // user, rather than as inline autocomplete suggest.
  // Returns true if the text was committed.
  // TODO: can the return type be void?
  bool CommitSuggestedText(bool skip_inline_autocomplete);

  // Accepts the currently showing instant preview, if any, and returns true.
  // Returns false if there is no instant preview showing.
  bool AcceptCurrentInstantPreview();

  // Invoked any time the text may have changed in the edit. Updates instant and
  // notifies the controller.
  void OnChanged();

  // Reverts the edit model back to its unedited state (permanent text showing,
  // no user input in progress).
  void Revert();

  // Directs the popup to start autocomplete.
  void StartAutocomplete(bool has_selected_text,
                         bool prevent_inline_autocomplete) const;

  // Closes the popup and cancels any pending asynchronous queries.
  void StopAutocomplete();

  // Determines whether the user can "paste and go", given the specified text.
  // This also updates the internal paste-and-go-related state variables as
  // appropriate so that the controller doesn't need to be repeatedly queried
  // for the same text in every clipboard-related function.
  bool CanPasteAndGo(const string16& text) const;

  // Navigates to the destination last supplied to CanPasteAndGo.
  void PasteAndGo();

  // Returns the url set by way of CanPasteAndGo.
  const GURL& paste_and_go_url() const { return paste_and_go_url_; }

  // Returns true if this is a paste-and-search rather than paste-and-go (or
  // nothing).
  bool is_paste_and_search() const {
    return (paste_and_go_transition_ != PageTransition::TYPED);
  }

  // Asks the browser to load the popup's currently selected item, using the
  // supplied disposition.  This may close the popup. If |for_drop| is true,
  // it indicates the input is being accepted as part of a drop operation and
  // the transition should be treated as LINK (so that it won't trigger the
  // URL to be autocompleted).
  void AcceptInput(WindowOpenDisposition disposition,
                   bool for_drop);

  // Asks the browser to load the item at |index|, with the given properties.
  void OpenURL(const GURL& url,
               WindowOpenDisposition disposition,
               PageTransition::Type transition,
               const GURL& alternate_nav_url,
               size_t index,
               const string16& keyword);

  bool has_focus() const { return has_focus_; }

  // Accessors for keyword-related state (see comments on keyword_ and
  // is_keyword_hint_).
  const string16& keyword() const { return keyword_; }
  bool is_keyword_hint() const { return is_keyword_hint_; }

  // Accepts the current keyword hint as a keyword. It always returns true for
  // caller convenience.
  bool AcceptKeyword();

  // Clears the current keyword.  |visible_text| is the (non-keyword) text
  // currently visible in the edit.
  void ClearKeyword(const string16& visible_text);

  // Returns the current autocomplete result.  This logic should in the future
  // live in AutocompleteController but resides here for now.  This method is
  // used by AutomationProvider::AutocompleteEditGetMatches.
  const AutocompleteResult& result() const;

  // Called when the view is gaining focus.  |control_down| is whether the
  // control key is down (at the time we're gaining focus).
  void OnSetFocus(bool control_down);

  // Sent before |OnKillFocus| and before the popup is closed.
  void OnWillKillFocus(gfx::NativeView view_gaining_focus);

  // Called when the view is losing focus.  Resets some state.
  void OnKillFocus();

  // Called when the user presses the escape key.  Decides what, if anything, to
  // revert about any current edits.  Returns whether the key was handled.
  bool OnEscapeKeyPressed();

  // Called when the user presses or releases the control key.  Changes state as
  // necessary.
  void OnControlKeyChanged(bool pressed);

  // Called when the user pastes in text.
  void on_paste() { paste_state_ = PASTING; }

  // Called when the user presses up or down.  |count| is a repeat count,
  // negative for moving up, positive for moving down.
  void OnUpOrDownKeyPressed(int count);

  // Called when any relevant data changes.  This rolls together several
  // separate pieces of data into one call so we can update all the UI
  // efficiently:
  //   |text| is either the new temporary text from the user manually selecting
  //     a different match, or the inline autocomplete text.  We distinguish by
  //     checking if |destination_for_temporary_text_change| is NULL.
  //   |destination_for_temporary_text_change| is NULL (if temporary text should
  //     not change) or the pre-change destination URL (if temporary text should
  //     change) so we can save it off to restore later.
  //   |keyword| is the keyword to show a hint for if |is_keyword_hint| is true,
  //     or the currently selected keyword if |is_keyword_hint| is false (see
  //     comments on keyword_ and is_keyword_hint_).
  void OnPopupDataChanged(
      const string16& text,
      GURL* destination_for_temporary_text_change,
      const string16& keyword,
      bool is_keyword_hint);

  // Called by the AutocompleteEditView after something changes, with details
  // about what state changes occured.  Updates internal state, updates the
  // popup if necessary, and returns true if any significant changes occurred.
  // If |allow_keyword_ui_change| is false then the change should not affect
  // keyword ui state, even if the text matches a keyword exactly. This value
  // may be false when the user is composing a text with an IME.
  bool OnAfterPossibleChange(const string16& new_text,
                             size_t selection_start,
                             size_t selection_end,
                             bool selection_differs,
                             bool text_differs,
                             bool just_deleted_text,
                             bool allow_keyword_ui_change);

  // Invoked when the popup is going to change its bounds to |bounds|.
  void PopupBoundsChangedTo(const gfx::Rect& bounds);

#if defined(UNIT_TEST)
  InstantCompleteBehavior instant_complete_behavior() const {
    return instant_complete_behavior_;
  }
#endif

 private:
  enum PasteState {
    NONE,           // Most recent edit was not a paste.
    PASTING,        // In the middle of doing a paste. We need this intermediate
                    // state because OnPaste() does the actual detection of
                    // paste, but OnAfterPossibleChange() has to update the
                    // paste state for every edit. If OnPaste() set the state
                    // directly to PASTED, OnAfterPossibleChange() wouldn't know
                    // whether that represented the current edit or a past one.
    PASTED,         // Most recent edit was a paste.
  };

  enum ControlKeyState {
    UP,                   // The control key is not depressed.
    DOWN_WITHOUT_CHANGE,  // The control key is depressed, and the edit's
                          // contents/selection have not changed since it was
                          // depressed.  This is the only state in which we
                          // do the "ctrl-enter" behavior when the user hits
                          // enter.
    DOWN_WITH_CHANGE,     // The control key is depressed, and the edit's
                          // contents/selection have changed since it was
                          // depressed.  If the user now hits enter, we assume
                          // he simply hasn't released the key, rather than that
                          // he intended to hit "ctrl-enter".
  };

  // AutocompleteControllerDelegate:
  virtual void OnResultChanged(bool default_match_changed);

  // Returns true if a query to an autocomplete provider is currently
  // in progress.  This logic should in the future live in
  // AutocompleteController but resides here for now.  This method is used by
  // AutomationProvider::AutocompleteEditIsQueryInProgress.
  bool query_in_progress() const;

  // Called whenever user_text_ should change.
  void InternalSetUserText(const string16& text);

  // Returns true if a keyword is selected.
  bool KeywordIsSelected() const;

  // Conversion between user text and display text. User text is the text the
  // user has input. Display text is the text being shown in the edit. The
  // two are different if a keyword is selected.
  string16 DisplayTextFromUserText(const string16& text) const;
  string16 UserTextFromDisplayText(const string16& text) const;

  // Copies the selected match into |match|.  If an update is in progress,
  // "selected" means "default in the latest matches".  If there are no matches,
  // does not update |match|.
  //
  // If |alternate_nav_url| is non-NULL, it will be set to the alternate
  // navigation URL for |url| if one exists, or left unchanged otherwise.  See
  // comments on AutocompleteResult::GetAlternateNavURL().
  //
  // TODO(pkasting): When manually_selected_match_ moves to the controller, this
  // can move too.
  void InfoForCurrentSelection(AutocompleteMatch* match,
                               GURL* alternate_nav_url) const;

  // Returns the default match for the current text, as well as the alternate
  // nav URL, if |alternate_nav_url| is non-NULL and there is such a URL.
  void GetInfoForCurrentText(AutocompleteMatch* match,
                             GURL* alternate_nav_url) const;

  // Returns true if |text| (which is display text in the current context)
  // parses as a URL, and in that case sets |url| to the calculated URL.
  // Subtle note: This ignores the desired_tld_ (unlike GetDataForURLExport()
  // and CurrentTextIsURL()).  The view needs this because it calls this
  // function during copy handling, when the control key is down to trigger the
  // copy.
  bool GetURLForText(const string16& text, GURL* url) const;

  // Reverts the edit box from a temporary text back to the original user text.
  // If |revert_popup| is true then the popup will be reverted as well.
  void RevertTemporaryText(bool revert_popup);

  // Accepts current keyword if the user only typed a space at the end of
  // |new_user_text| comparing to the |old_user_text|.
  // Returns true if the current keyword is accepted.
  bool MaybeAcceptKeywordBySpace(const string16& old_user_text,
                                 const string16& new_user_text);

  // Checks if |allow_exact_keyword_match_| should be set to true according to
  // the old and new user text and the current caret position. It does not take
  // other factors into account, e.g. if the view is ready to change the keyword
  // ui or not. This is only for the case of inserting a space character in the
  // middle of the text. See the comment of |allow_exact_keyword_match_| below.
  bool ShouldAllowExactKeywordMatch(const string16& old_user_text,
                                    const string16& new_user_text,
                                    size_t caret_position);

  // Checks if a given character is a valid space character for accepting
  // keyword.
  static bool IsSpaceCharForAcceptingKeyword(wchar_t c);

  scoped_ptr<AutocompleteController> autocomplete_controller_;

  AutocompleteEditView* view_;

  AutocompletePopupModel* popup_;

  AutocompleteEditController* controller_;

  // Whether the edit has focus.
  bool has_focus_;

  // The URL of the currently displayed page.
  string16 permanent_text_;

  // This flag is true when the user has modified the contents of the edit, but
  // not yet accepted them.  We use this to determine when we need to save
  // state (on switching tabs) and whether changes to the page URL should be
  // immediately displayed.
  // This flag will be true in a superset of the cases where the popup is open.
  bool user_input_in_progress_;

  // The text that the user has entered.  This does not include inline
  // autocomplete text that has not yet been accepted.
  string16 user_text_;

  // When the user closes the popup, we need to remember the URL for their
  // desired choice, so that if they hit enter without reopening the popup we
  // know where to go.  We could simply rerun autocomplete in this case, but
  // we'd need to either wait for all results to come in (unacceptably slow) or
  // do the wrong thing when the user had chosen some provider whose results
  // were not returned instantaneously.
  //
  // This variable is only valid when user_input_in_progress_ is true, since
  // when it is false the user has either never input anything (so there won't
  // be a value here anyway) or has canceled their input, which should be
  // treated the same way.  Also, since this is for preserving a desired URL
  // after the popup has been closed, we ignore this if the popup is open, and
  // simply ask the popup for the desired URL directly.  As a result, the
  // contents of this variable only need to be updated when the popup is closed
  // but user_input_in_progress_ is not being cleared.
  string16 url_for_remembered_user_selection_;

  // Inline autocomplete is allowed if the user has not just deleted text, and
  // no temporary text is showing.  In this case, inline_autocomplete_text_ is
  // appended to the user_text_ and displayed selected (at least initially).
  //
  // NOTE: When the popup is closed there should never be inline autocomplete
  // text (actions that close the popup should either accept the text, convert
  // it to a normal selection, or change the edit entirely).
  bool just_deleted_text_;
  string16 inline_autocomplete_text_;

  // Used by OnPopupDataChanged to keep track of whether there is currently a
  // temporary text.
  //
  // Example of use: If the user types "goog", then arrows down in the
  // autocomplete popup until, say, "google.com" appears in the edit box, then
  // the user_text_ is still "goog", and "google.com" is "temporary text".
  // When the user hits <esc>, the edit box reverts to "goog".  Hit <esc> again
  // and the popup is closed and "goog" is replaced by the permanent_text_,
  // which is the URL of the current page.
  //
  // original_url_ is only valid when there is temporary text, and is used as
  // the unique identifier of the originally selected item.  Thus, if the user
  // arrows to a different item with the same text, we can still distinguish
  // them and not revert all the way to the permanent_text_.
  bool has_temporary_text_;
  GURL original_url_;

  // When the user's last action was to paste, we disallow inline autocomplete
  // (on the theory that the user is trying to paste in a new URL or part of
  // one, and in either case inline autocomplete would get in the way).
  PasteState paste_state_;

  // Whether the control key is depressed.  We track this to avoid calling
  // UpdatePopup() repeatedly if the user holds down the key, and to know
  // whether to trigger "ctrl-enter" behavior.
  ControlKeyState control_key_state_;

  // The keyword associated with the current match.  The user may have an actual
  // selected keyword, or just some input text that looks like a keyword (so we
  // can show a hint to press <tab>).  This is the keyword in either case;
  // is_keyword_hint_ (below) distinguishes the two cases.
  string16 keyword_;

  // True if the keyword associated with this match is merely a hint, i.e. the
  // user hasn't actually selected a keyword yet.  When this is true, we can use
  // keyword_ to show a "Press <tab> to search" sort of hint.
  bool is_keyword_hint_;

  // Paste And Go-related state.  See CanPasteAndGo().
  mutable GURL paste_and_go_url_;
  mutable PageTransition::Type paste_and_go_transition_;
  mutable GURL paste_and_go_alternate_nav_url_;

  Profile* profile_;

  // Should instant be updated? This is needed as prior to accepting the current
  // text the model is reverted, which triggers resetting instant. We don't want
  // to update instant in this case, so we use the flag to determine if this is
  // happening.
  bool update_instant_;

  // Indicates if the upcoming autocomplete search is allowed to be treated as
  // an exact keyword match. If it's true then keyword mode will be triggered
  // automatically if the input is "<keyword> <search string>". We only allow
  // such trigger when:
  // 1.A single space character is added at the end of a keyword, such as:
  //   (assume "foo" is a keyword, | is the input caret)
  //   foo| -> foo |
  //   foo[bar] -> foo |  ([bar] indicates a selected text "bar")
  // 2.A single space character is inserted after a keyword when the caret is
  //   not at the end of the line, such as:
  //   foo|bar -> foo |bar
  //
  // It has no effect if a keyword is already selected.
  bool allow_exact_keyword_match_;

  // Last value of InstantCompleteBehavior supplied to |SetSuggestedText|.
  InstantCompleteBehavior instant_complete_behavior_;

  DISALLOW_COPY_AND_ASSIGN(AutocompleteEditModel);
};

#endif  // CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_EDIT_H_