"{ Encoding: utf8 }"

"{ Package: 'stx:libwidg' }"

"{ NameSpace: Smalltalk }"

Object subclass:#EditTextViewCompletionSupport

	instanceVariableNames:'completionView completionProcess editView autoSelect

		editViewLostFocusBlock'

	classVariableNames:'LastCompletions'

	poolDictionaries:''

	category:'Views-Text'

!

!EditTextViewCompletionSupport class methodsFor:'documentation'!

documentation

"

    An abstract supperclass to support completion in text views.

    Individual completion engines may create a subclass of 

    EditTextCompletionSupport and customize it.

    Basically, they have to implement #computeCompletions

    [author:]

        Claus Gittinger

    [instance variables:]

    [class variables:]

    [see also:]

"

! !

!EditTextViewCompletionSupport class methodsFor:'instance creation'!

for:anEditView

    ^ self new editView:anEditView

! !

!EditTextViewCompletionSupport class methodsFor:'queries'!

isAbstract

    ^ self == EditTextViewCompletionSupport

    "Created: / 26-09-2013 / 16:22:11 / Jan Vrany <jan.vrany@fit.cvut.cz>"

! !

!EditTextViewCompletionSupport methodsFor:'accessing'!

editView:anEditTextView

    editView := anEditTextView.

! !

!EditTextViewCompletionSupport methodsFor:'events'!

buttonPress:button x:x y:y

    self closeCompletionView.

!

editViewLostFocus

    "this is a hack for Windows:

     on windows, an activate:false event is first sent to my textView,

     then an activate is sent to the completion popup.

     this is done BEFORE the buttonPress event is delivered.

     therefore, allow for the activate of the completionMenu and its button event to be processed.

     before forcing it to be closed..."

    completionView notNil ifTrue:[

        editView graphicsDevice anyButtonPressed ifTrue:[

            editView sensor pushUserEvent:#editViewLostFocus for:self.

        ] ifFalse:[

            self closeCompletionView

        ]

    ].

!

handleKeyPress:key x:x y:y

    "return true, if I have eaten this keypress"

    "/ completeImmediate := UserPreferences current immediateCodeCompletion.

    "/ open on CTRL- or TAB-key?

    (completionView notNil and:[completionView realized]) ifFalse:[

        editView hasSelection ifFalse:[

            ch := editView characterBeforeCursor.

            (ch notNil "/ i.e. not at begin of line

                (key == #Control_L or:[ key == #Ctrl or:[ key == #Control_R or:[ key == #Control]]]) ifTrue:[

                    UserPreferences current codeCompletionOnControlKey ifTrue:[

                        autoSelect := true.

                        self updateCompletionList

                    ]

                ].

                ((key == #Tab) and:[editView sensor shiftDown not]) ifTrue:[

                    UserPreferences current codeCompletionOnTabKey ifTrue:[

                        "/ only if the character after the cursor is a separator!!

                        "/ otherwise, we cannot insert tabs 

                        ((ch := editView characterAfterCursor) isNil or:[ch isSeparator]) ifTrue:[

                            autoSelect := true.

                            self updateCompletionList.

                            ^ true

                        ].

                    ].

                ]

            ].

        ].

        ^ false.

    ].

    editView cursorCol <= 1 ifTrue:[^ false].

    "/ key for completion view ? (careful: do not forward too many, it would disturb user's typing)

    key isCharacter ifFalse:[

        "/ forward to menu

        (completionView notNil) ifTrue:[

            "/never

            eatCursorLeftOrRight := false.

"/                                    completeImmediate not

"/                                    or:[ editView sensor shiftDown 

"/                                    or:[ editView sensor ctrlDown ]].

            "/ only with shift or ctrl

            eatCursorUpDown := 

                    (UserPreferences current codeCompletionViewKeyboardNavigationNeedsModifier not)

                    or:[ editView sensor shiftDown 

                    or:[ editView sensor ctrlDown]].

            ((key == #CursorDown and:[eatCursorUpDown])

                or:[ (key == #CursorUp and:[eatCursorUpDown])

                or:[ ((key == #CursorLeft) and:[eatCursorLeftOrRight])

                or:[ ((key == #CursorRight) and:[eatCursorLeftOrRight])

                or:[ ((key == #Return) and:[ completionView hasSelection ])

            ]]]]) ifTrue:[

                "/ forward to completion view

                completionView sensor pushUserEvent:#value for:[ completionView keyPress:key x:0 y:0 ].

                ^ true.

            ].

            (key == #Control_L or:[ key == #Control_R or:[ key == #Control or:[ key == #Ctrl ]]]) ifTrue:[

                "/ CTRL is a toggle

"/                self closeCompletionView.   

"/                ^ true.

                ^ false "/ don't eat

            ].

            (key == #Escape) ifTrue:[

                self closeCompletionView.

                ^ true  "/ EAT

            ].

            "/ shift does not close

            (key == #Shift_L or:[ key == #Shift_R or:[ key == #Shift]]) ifTrue:[

                ^ false "/ don' eat

            ].

            (key == #BackSpace) ifTrue:[

                ^ false "/ don' eat

            ].

            self closeCompletionView.

            ^ false "/ don' eat

        ].

    ].

    ^ false.

    "Modified: / 24-08-2017 / 21:32:52 / cg"

    "Modified: / 03-07-2018 / 13:41:45 / sr"

    "Modified: / 05-06-2019 / 17:06:15 / Claus Gittinger"

!

postKeyPress:key

    UserPreferences current immediateCodeCompletion ifFalse:[

        "/ only update, if already open

        completionView isNil ifTrue:[^ self].

    ].

    "/ (completionView notNil and:[completionView realized]) ifTrue:[^ self].

    editView hasSelection ifTrue:[^ self].

    ch := editView characterBeforeCursor.

    (ch notNil and:[ch isLetterOrDigitOrUnderline]) ifFalse:[^ self].

    (key == #BackSpace or:[key == #BasicBackspace]) ifTrue:[

        autoSelect := false.

        self updateCompletionList.

        ^ self

    ].

    key isCharacter ifTrue:[

        (doComplete := key isSeparator not) ifFalse:[

            "/ also on a separator, but only if at the end of a non-empty line

            doComplete := editView lineStringBeforeCursor withoutSeparators notEmpty.

        ].

        doComplete ifFalse:[

            self closeCompletionView

        ] ifTrue:[

            autoSelect := false.

            self updateCompletionList.

        ].

        ^ self

    ].

!

startTimeoutForEditViewLostFocus

    "see comment in #editViewLostFocus"

    editViewLostFocusBlock isNil ifTrue:[

        editViewLostFocusBlock := [self editViewLostFocus].

    ].

    Processor addTimedBlock:editViewLostFocusBlock afterMilliseconds:200.

! !

!EditTextViewCompletionSupport methodsFor:'private'!

computeAndShowCompletions

    "compute completions, then push an event to show them"

    |completions|

    completions := self computeCompletions.

    completions notEmptyOrNil ifTrue:[

        self assert:completions isArray.

        self assert:completions size == 4.

        editView sensor

            pushUserEvent:#'suggestionsArrived:implementations:actions:autoSelect:'

            for:self

            withArguments:completions

    ].

    "Created: / 15-07-2019 / 17:29:54 / Claus Gittinger"

    "Modified: / 24-07-2019 / 07:53:35 / Claus Gittinger"

!

computeCompletions

    "compute the completions.

     Don't know how to do this here."

    ^ nil

    "Created: / 26-09-2013 / 17:35:17 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

release

    self stopCompletionProcess.

    self closeCompletionView.

    super release

!

startCompletionProcess

    "start the code completion process in the background"

    |initialList cursorX cursorY p|

    "/ terminate any previous process

    self synchronized:[

        self stopCompletionProcess.

    ].

    (editView sensor hasKeyPressEventFor:nil) ifTrue:[ 

        "/ 'cl' printCR.

        self closeCompletionView. 

        ^ self

    ].

    ((cursorX := editView xOfCursor) isNil

    or:[ (cursorY := editView yOfCursor) isNil ]) ifTrue:[

        "/ no cursor - user is selecting, or cursor has been scrolled out of sight.

        "/ 'cl2' printCR.

        self closeCompletionView. 

        ^ self

    ].

    completionView isNil ifTrue:[

        initialList := #( 'Busy...' ).

        "/ 'op1' printCR.

    ] ifFalse:[

        initialList := completionView list.

        "/ 'op2' printCR.

    ].

    self openCompletionView:initialList.

    completionProcess := p := 

        [

            [

                "/ protect end-user applications from errors

                Error handle:[:ex |

                    (ParseError accepts:ex creator) ifFalse:[

                        Smalltalk isSmalltalkDevelopmentSystem ifTrue:[ ex reject ]

                    ].

                ] do:[ 

                    |startTime|

                    startTime := Timestamp now.

                    "/ Wait a while to give user chance finish typing.

                    "/ This also reduces CPU consumption by avoiding

                    "/ useless computation

                    Delay waitForMilliseconds: 200.

                    (editView topView isDebugView) ifTrue:[

                        ControlInterrupt ignoreIn:[

                            self computeAndShowCompletions.

                        ].    

                    ] ifFalse:[    

                        self computeAndShowCompletions.

                    ].

                ].

                p == completionProcess ifTrue:[

                    completionProcess := nil

                ]

            ] ifCurtailed:[

                "/ completionView notNil ifTrue:[

                "/    completionView topView destroy

                "/ ].    

            ].    

        ] newProcess.

    "/ p priority:(Processor activePriority - 1).

    p priorityRange:(Processor activePriority-1 to:Processor activePriority).

    p resume.

    "Modified: / 26-09-2013 / 17:36:11 / Jan Vrany <jan.vrany@fit.cvut.cz>"

    "Modified: / 15-07-2019 / 17:30:55 / Claus Gittinger"

!

stopCompletionProcess

    "kill any background completion process"

    |p|

    (p := completionProcess) notNil ifTrue:[

        completionProcess := nil.

        p terminate.

    ].

!

updateCompletionList

    "called for keypress events"

    self startCompletionProcess.

! !

!EditTextViewCompletionSupport methodsFor:'private-API'!

closeCompletionView

    |v|

    (v := completionView) notNil ifTrue:[

        completionView := nil.

        "/ let it close itself - avoids synchronization problems

        v sensor

            pushUserEvent:#value

            for:[ v topView destroy ]

    ].

    "Modified (format): / 14-09-2018 / 22:08:05 / Claus Gittinger"

!

openCompletionView

    "Opens the completion view with an initial list. Called as soon as

     completion is initiated but completion options are not yet computed."

    self openCompletionView: (Array with: 'Busy...')

    "Created: / 26-09-2013 / 17:06:12 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

openCompletionView: list

    "Makes sure the completion view is opened and with given `list`."

    | textCursorPosInTextView textCursorPosOnScreen movePos topView 

      screenBounds screenBoundsCorner 

      helpViewsExtent helpViewsWidth helpViewsHeight|

    "/ move the window away from the text cursor (to not cover what user types in)

    "/ get the screen-relative position of the text cursor

    textCursorPosInTextView := editView xOfCursor @ editView yOfCursor.

    "/ care for the scroll-offset (xOfCursor/yOFCursor gives me               

    textCursorPosInTextView := textCursorPosInTextView - (editView viewOrigin x @ 0).

    textCursorPosOnScreen := editView device 

                    translatePoint:textCursorPosInTextView 

                    fromView:editView toView:nil.

    "/ currently, we have to stay away a bit, to avoid getting the focus

    "/ this will be somewhat to the down-right of the textCursor

    movePos := textCursorPosOnScreen + (60 @ (editView font height)).

    completionView isNil ifTrue:[

        completionView := CodeCompletionHelpMenuView new.

        completionView name:'completion'.

        completionView level:0.

        completionView list:list.

        completionView enable:false.

        completionView extent:completionView preferredExtentForContents.

        "/ completionView font: editView font.

        topView := CodeCompletionHelpView with:completionView.

        topView editView:editView.

    ] ifFalse:[

        completionView list:list.

        topView := completionView topView.

    ].

    topView ~~ completionView ifTrue:[

        topView resizeToFit.

        "/ make sure, the window is visible

        screenBounds := topView device monitorBoundsAt:topView origin.

        screenBoundsCorner := screenBounds corner.

        helpViewsExtent := topView extent.

        helpViewsWidth := helpViewsExtent x.

        helpViewsHeight := helpViewsExtent y.

        "/ if it does not lie completely inside the screen, move it     

        (movePos x + helpViewsWidth) > screenBoundsCorner x ifTrue:[

            movePos := (textCursorPosOnScreen x - 60 - helpViewsWidth) @ movePos y.

        ].

        (movePos y + helpViewsHeight) > screenBoundsCorner y ifTrue:[

            movePos := movePos x @ (textCursorPosOnScreen y - helpViewsHeight).

        ].

        movePos y < 0 ifTrue:[

            movePos := movePos x @ 0

        ].    

        topView origin:movePos.

    ].

    "Created: / 26-09-2013 / 17:07:34 / Jan Vrany <jan.vrany@fit.cvut.cz>"

! !

!EditTextViewCompletionSupport class methodsFor:'documentation'!

version

    ^ '$Header$'

!

version_CVS

    ^ '$Header$'

! !