"{ Package: 'jv:smallsense' }"

"{ NameSpace: SmallSense }"

EditTextViewCompletionSupport subclass:#CompletionController
	instanceVariableNames:'support seqno completeIfUnambiguous'
	classVariableNames:''
	poolDictionaries:''
	category:'SmallSense-Core'
!


!CompletionController class methodsFor:'instance creation'!

new
    "return an initialized instance"

    ^ self basicNew initialize.
! !

!CompletionController class methodsFor:'testing'!

isAbstract
    ^ false

    "Created: / 17-10-2013 / 00:29:49 / Jan Vrany <jan.vrany@fit.cvut.cz>"
! !

!CompletionController methodsFor:'accessing'!

support
    ^ support
!

support:anEditSupport
    support := anEditSupport.
! !

!CompletionController methodsFor:'events'!

handleKeyPress:key x:x y:y

    key == #Control_L ifTrue:[
        completionView notNil ifTrue:[
            ^ false.
        ].
    ].

    key == #CodeCompletion  ifTrue: [
        autoSelect := true.    
        self startCompletionProcess.
        ^ true
    ].

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

        c := editView characterBeforeCursor.
        (c notNil and:[c isAlphaNumeric]) ifTrue:[
             ^ false
        ].
    ].     


    completionView notNil ifTrue:[
        (key == #Return and:[completionView hasSelection]) ifTrue:[
            self complete.
            ^ true.
        ].
        key == #Tab ifTrue:[ 
            self handleKeyPressTab.  
            ^ true
        ].
        key isCharacter ifTrue:[
            self updateSelection.
        ].
    ].
    ^ super handleKeyPress:key x:x y:y

    "Created: / 27-09-2013 / 15:38:44 / Jan Vrany <jan.vrany@fit.cvut.cz>"
    "Modified: / 31-03-2014 / 22:55:01 / Jan Vrany <jan.vrany@fit.cvut.cz>"
!

handleKeyPressTab
    "Tab has been pressed, try to complete longest common prefix"

    | prefix matching longest minlen |

    prefix := support wordBeforeCursor string.                                        
    matching := OrderedCollection new.
    minlen := SmallInteger maxVal.
    completionView list do:[:po |
        | s |

        s := po stringToComplete.
        (s startsWith: prefix) ifTrue:[
            matching add: po -> s.
            minlen := minlen min: s size.
        ].
    ].
    matching isEmpty ifTrue:[
        completionView flash.
        ^self.
    ].
    matching size == 1 ifTrue:[
        self complete: matching first key.
    ].

    longest := String streamContents:[:s |
        | i |

        s nextPutAll: prefix.
        i := prefix size + 1.
        [ i <= minlen ] whileTrue:[
            | c |

            c := matching first value at: i.
            (matching allSatisfy:[:e|(e value at: i) == c]) ifTrue:[
                s nextPut:c.
                i := i + 1.
            ] ifFalse:[
                "/ terminate the loop    
                i := minlen + 2.
            ]
        ]
    ].
    longest size = prefix size ifTrue:[
        completionView flash.
        ^self.
    ].
    editView insertStringAtCursor:(longest copyFrom: prefix size + 1).

    "Created: / 31-03-2014 / 22:55:01 / Jan Vrany <jan.vrany@fit.cvut.cz>"
!

postKeyPress:key
    seqno := seqno + 1.
    seqno == SmallInteger maxVal ifTrue:[
        seqno := 0.
    ].

    UserPreferences current immediateCodeCompletion ifFalse:[
        "/ only update, if already open
        completionView isNil ifTrue:[^ self].
    ].

    (key == #BackSpace or:[key == #BasicBackspace]) ifTrue:[
        self closeCompletionView.
        ^ self
    ].

    key isCharacter ifTrue:[
        key isLetterOrDigit not ifTrue:[
            self closeCompletionView
        ] ifFalse:[
            | c |

            c := editView characterBeforeCursor.
            (c notNil and:[c isLetterOrDigit]) ifTrue:[
                c := editView characterUnderCursor.
                c isSeparator ifTrue:[
                    autoSelect := false.
                    self updateCompletionList.
                ].
            ]
        ].
        ^ self
    ].

    "Created: / 28-09-2013 / 00:21:00 / Jan Vrany <jan.vrany@fit.cvut.cz>"
    "Modified: / 03-10-2013 / 11:01:21 / Jan Vrany <jan.vrany@fit.cvut.cz>"
! !

!CompletionController methodsFor:'initialization'!

initialize
    "Invoked when a new instance is created."

    "/ please change as required (and remove this comment)
    "/ support := nil.
    seqno := 0.
    completeIfUnambiguous := UserPreferences current smallSenseCompleteIfUnambiguous.

    "/ super initialize.   -- commented since inherited method does nothing

    "Modified: / 18-01-2014 / 23:10:49 / Jan Vrany <jan.vrany@fit.cvut.cz>"
! !

!CompletionController methodsFor:'private'!

complete
    self complete: completionView selection.

    "Created: / 27-09-2013 / 15:38:44 / Jan Vrany <jan.vrany@fit.cvut.cz>"
    "Modified: / 31-03-2014 / 23:22:12 / Jan Vrany <jan.vrany@fit.cvut.cz>"
!

complete: item
    self closeCompletionView.
    item insert

    "Created: / 31-03-2014 / 23:21:58 / Jan Vrany <jan.vrany@fit.cvut.cz>"
!

stopCompletionProcess
    "kill any background completion process"

    editView sensor flushUserEventsFor: self.     
    super stopCompletionProcess

    "Created: / 02-10-2013 / 15:09:58 / Jan Vrany <jan.vrany@fit.cvut.cz>"
    "Modified: / 03-10-2013 / 11:03:01 / Jan Vrany <jan.vrany@fit.cvut.cz>"
!

updateCompletionList
    "called for keypress events"

    completionView isNil ifTrue:[
        super updateCompletionList
    ] ifFalse:[
         self updateSelection.
    ].

    "Created: / 27-09-2013 / 15:58:01 / Jan Vrany <jan.vrany@fit.cvut.cz>"
    "Modified: / 28-09-2013 / 00:15:56 / Jan Vrany <jan.vrany@fit.cvut.cz>"
!

updateSelection
    "Updates selection in completion view based on
     currently typed partial text. Return true if
     the complection window should be closed or false
     if it shall be kept open."

    | matches word |

    word := support wordBeforeCursor.
    matches := completionView list select:[:po | po stringToComplete startsWith: word ].
    matches notEmptyOrNil ifTrue:[
        matches size == 1 ifTrue:[
            completionView selection:  matches anElement.
            completeIfUnambiguous ifTrue:[
                self complete.
                ^ true
            ]
        ] ifFalse:[
            | selection |

            selection := matches inject: matches anElement into:[:mostrelevant :each |
                each relevance > mostrelevant relevance 
                    ifTrue:[each]
                    ifFalse:[mostrelevant]
            ].
            completionView selection: selection.
        ]
    ] ifFalse:[
        completionView selection: nil.
    ].
    ^ false.

    "Created: / 27-09-2013 / 16:16:18 / Jan Vrany <jan.vrany@fit.cvut.cz>"
    "Modified (format): / 18-01-2014 / 23:24:59 / Jan Vrany <jan.vrany@fit.cvut.cz>"
! !

!CompletionController methodsFor:'private-API'!

closeCompletionView
    |v|

    self stopCompletionProcess.
    (v := completionView) notNil ifTrue:[
        completionView := nil.
        "/ let it close itself - avoids synchronization problems
        v sensor
            pushUserEvent:#value
            for:[ v topView destroy ].
    ].

    "Created: / 02-10-2013 / 13:57:27 / Jan Vrany <jan.vrany@fit.cvut.cz>"
    "Modified: / 04-10-2013 / 21:14:06 / Jan Vrany <jan.vrany@fit.cvut.cz>"
!

computeCompletions
    "Actually compute the completions and update the completion view."  

    | completions |

    editView sensor flushUserEventsFor: self.

    "/ Wait a while to give user chance finish typing.
    "/ This also reduces CPU consumption by avoiding
    "/ useless computation
    Delay waitForMilliseconds: 200. 
"/    self updateCompletions: support computeCompletion
    completions := support computeCompletion.
    completions notEmptyOrNil ifTrue:[
        editView sensor pushUserEvent: #updateCompletions:sequence: for: self withArguments: (Array with: completions with: seqno)
    ].

    "Created: / 27-09-2013 / 13:12:11 / Jan Vrany <jan.vrany@fit.cvut.cz>"
    "Modified: / 03-10-2013 / 07:17:10 / Jan Vrany <jan.vrany@fit.cvut.cz>"
!

openCompletionView
    self openCompletionView: #()

    "Created: / 27-09-2013 / 16:17:58 / Jan Vrany <jan.vrany@fit.cvut.cz>"
!

openCompletionView: list
    "Makes sure the completion view is opened and with given `list`."
    
    | movePos topView x y  windowExtent screenExtent |
    "/ move the window

    list isEmpty ifTrue:[ ^ self ].
    list = #( 'Busy...' ) ifTrue:[ ^ self ].  

    x := (editView xOfCol:editView cursorCol  inVisibleLine:editView cursorLine)
            - 16"icon" - (editView widthOfString:  support wordBeforeCursor) - 5"magic constant".
    y := editView yOfCursor + editView font maxHeight + 3.
    movePos := (editView originRelativeTo: nil) + (x @ y).

    completionView isNil ifTrue:[

        completionView := CompletionView new.
        completionView completionController: self.  
        completionView list:list.
        completionView font: editView font.
        topView := completionView.

        windowExtent := completionView extent copy.
        screenExtent := Screen current monitorBoundsAt: movePos.
        (screenExtent height) < (movePos y + windowExtent y) ifTrue:[
            movePos y: (movePos y - windowExtent y - editView font maxHeight - 5).
        ].
        topView origin:movePos.
"/        topView resizeToFit.
        self updateSelection ifFalse:[
            topView open.
        ].
    ] ifFalse:[
        completionView list:list.
        self updateSelection.
"/        topView := completionView topView.
"/        topView ~~ completionView ifTrue:[
"/            topView origin:movePos.
"/            topView resizeToFit.
"/        ]
    ].

    "Created: / 27-09-2013 / 14:01:27 / Jan Vrany <jan.vrany@fit.cvut.cz>"
    "Modified: / 27-02-2014 / 10:13:24 / Jan Vrany <jan.vrany@fit.cvut.cz>"
!

updateCompletions: completionResult sequence: sequence
    seqno == sequence ifTrue:[
        self openCompletionView: completionResult 
    ].

    "Created: / 03-10-2013 / 07:14:06 / Jan Vrany <jan.vrany@fit.cvut.cz>"
    "Modified: / 03-10-2013 / 11:02:12 / Jan Vrany <jan.vrany@fit.cvut.cz>"
! !

!CompletionController class methodsFor:'documentation'!

version_HG

    ^ '$Changeset: <not expanded> $'
! !