"

 COPYRIGHT (c) 1989 by Claus Gittinger

	      All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

EditTextView subclass:#TextCollector

       instanceVariableNames:'entryStream lineLimit destroyAction

			      outstandingLines outstandingLine

			      flushBlock flushPending collecting timeDelay access'

       classVariableNames:''

       poolDictionaries:''

       category:'Views-Text'

!

TextCollector comment:'

COPYRIGHT (c) 1989 by Claus Gittinger

	      All Rights Reserved

'!

!TextCollector class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1989 by Claus Gittinger

	      All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

!

version

"

"

!

documentation

"

    a view for editable text, which also understands some stream messages.

    Instances of this view can take the place of a stream and display the 

    received text.

    Its main use in the system is the Transcript, but it can also be used for

    things like trace-windows etc.

    If collecting is turned on, a textcollector will not immediately display 

    entered text, but wait for some short time (timeDelay) and collect incoming 

    data - finally updating the whole chunk in one piece. 

    This helps slow display devices, which would otherwise scroll a lot. 

    (on fast displays this is less of a problem).

    The total number of lines kept is controlled by lineLimit, if more lines 

    than this limit are added at the bottom, the textcollector will forget lines 

    at the top. 

    You can set linelimit to nil (i.e. no limit), but you may need a lot 

    of memory then ...

"

! !

!TextCollector class methodsFor:'defaults'!

defaultLineLimit

    "the number of lines remembered by default"

    ^ 600

! 

defaultTranscriptSize

    "the number of cols/lines by which the Transcript should come up"

    ^ 70@11

! 

defaultTimeDelay

    "the time in seconds to wait & collect by default"

    ^ 0.3 

! !

!TextCollector class methodsFor:'instance creation'!

newTranscript

    |topView transcript f v fg bg cFg cBg lines cols|

    topView := StandardSystemView label:'Transcript' minExtent:(100 @ 100).

    v := HVScrollableView for:self miniScrollerH:true miniScrollerV:false in:topView.

    v origin:(0.0 @ 0.0) corner:(1.0 @ 1.0).

    transcript := v scrolledView.

    "transcript partialLines:false."

    f := transcript font.

    "

     should add the height of the frame & scrollbars to be exact ...

    "

    cols := self defaultTranscriptSize x.

    lines := self defaultTranscriptSize y.

    topView extent:(((f widthOf:'x') * cols) @ (f height * lines)).

    Smalltalk at:#Transcript put:transcript.

    "

     fancy feature: whenever Transcript is closed, reset to StdError

    "

    transcript destroyAction:[Smalltalk at:#Transcript put:Stderr].

    fg := StyleSheet colorAt:'transcriptForegroundColor' default:transcript foregroundColor.

    bg := StyleSheet colorAt:'transcriptBackgroundColor' default:transcript backgroundColor.

    transcript foregroundColor:fg backgroundColor:bg.

    cFg := StyleSheet colorAt:'transcriptCursorForegroundColor' default:bg.

    cBg := StyleSheet colorAt:'transcriptCursorBackgroundColor' default:fg.

    transcript cursorForegroundColor:cFg backgroundColor:cBg. 

    topView open.

    "transcript lineLimit:1000. " "or whatever you think makes sense"

    ^ transcript

! !

!TextCollector methodsFor:'initialize / release'!

initialize

    super initialize.

    outstandingLines := OrderedCollection new.

    flushBlock := [self endEntry].

    flushPending := false.

    collecting := true.

    timeDelay := self class defaultTimeDelay.

    access := Semaphore forMutualExclusion.

    lineLimit := self class defaultLineLimit.

    entryStream := ActorStream new.

    entryStream nextPutBlock:[:something | self nextPut:something].

    entryStream nextPutAllBlock:[:something | self nextPutAll:something]

!

initializeMiddleButtonMenu

    |idx|

    super initializeMiddleButtonMenu.

    "

     textcollectors do not support #accept

     remove it from the menu (and the preceeding separating line)

    "

    idx := middleButtonMenu indexOf:#accept.

    idx ~~ 0 ifTrue:[

	middleButtonMenu remove:idx.

	(middleButtonMenu labels at:(idx - 1)) = '-' ifTrue:[

	    middleButtonMenu remove:idx - 1

	].

    ].

!

reinitialize

    "recreate access-semaphore; image could have been save (theoretically)

     with the semaphore locked - int this case, we had a deadlock"

    flushPending := false.

    access := Semaphore forMutualExclusion.

    super reinitialize.

!

mapped

    "view became visible - show collected lines (if any)"

    super mapped.

    self endEntry

!

destroy

    destroyAction notNil ifTrue:[

	destroyAction value

    ].

    Processor removeTimedBlock:flushBlock.

    flushBlock := nil.

    outstandingLines := OrderedCollection new.

    outstandingLine := ''.

    super destroy

! !

!TextCollector methodsFor:'accessing'!

collect:aBoolean

    "turn on/off collecting - if on, do not output immediately

     but collect text and output en-bloque after some time delta"

    collecting := aBoolean

!

lineLimit:aNumber

    "define the number of text-lines I am supposed to hold"

    lineLimit := aNumber

!

destroyAction:aBlock

    "define the action to be performed when I get destroyed.

     This is a special feature, to allow resetting Transcript to Stderr

     when closed. (see TextCollectorclass>>newTranscript)"

    destroyAction := aBlock

!

endEntry

    "flush collected output"

    |nLines lines|

    shown ifFalse:[^ self].

    Processor removeTimedBlock:flushBlock.

    flushPending ifFalse:[^ self].

    access critical:[

	flushPending := false.

	outstandingLines size ~~ 0 ifTrue:[

	    "insert the bunch of lines - if any"

	    lines := outstandingLines.

	    outstandingLines := OrderedCollection new.

	    nLines := lines size.

	    (nLines ~~ 0) ifTrue:[

		self insertLines:lines withCr:true.

		self withCursorOffDo:[

		    (cursorLine >= (firstLineShown + nFullLinesShown)) ifTrue:[

			self scrollDown:nLines

		    ]

		].

	    ].

	].

	"and the last partial line - if any"

	outstandingLine notNil ifTrue:[

	    self insertStringAtCursor:outstandingLine.

	    outstandingLine := ''.

	].

	self checkLineLimit

    ]

! !

!TextCollector methodsFor:'private'!

checkLineLimit

    "this method checks if the text has become too large (> lineLimit)

     and cuts off some lines at the top if so; it must be called whenever lines

     have been added to the bottom"

    |nDel|

    lineLimit notNil ifTrue:[

	(cursorLine > lineLimit) ifTrue:[

	    nDel := list size - lineLimit.

	    list removeFromIndex:1 toIndex:nDel.

	    cursorLine := cursorLine - nDel.

	    firstLineShown := firstLineShown - nDel.

	    (firstLineShown < 1) ifTrue:[

		cursorLine := cursorLine - firstLineShown + 1.

		firstLineShown := 1

	    ].

	    self contentsChanged

	]

    ]

!

installDelayedUpdate

    "arrange for collecting input for some time,

     and output all buffered strings at once after a while.

     This makes output to the transcript much faster on systems

     with poor scrolling performance (i.e. dump vga cards ...)."

    |wg p|

    flushPending ifFalse:[

	flushPending := true.

	"

	 we could run under a process, which dies in the meantime;

	 therefore, we have to arrange for the transcript process to

	 be interrupted and do the update.

	"

	wg := self windowGroup.

	wg isNil ifTrue:[

	    p := Processor activeProcess

	] ifFalse:[

	    p := wg process

	].

	Processor addTimedBlock:flushBlock for:p afterSeconds:timeDelay.

    ]

! !

!TextCollector methodsFor:'stream messages'!

lineLength

    ^ width // (font width)

!

nextPut:something

    "this allows TextCollectors to be used Stream-wise"

    flushPending ifTrue:[

	self endEntry

    ].

    (something isMemberOf:Character) ifTrue:[

	((something == Character cr) or:[something == Character nl]) ifTrue:[

	    ^ self cr

	].

	self insertCharAtCursor:something

    ] ifFalse:[

	self insertStringAtCursor:(something printString).

	self checkLineLimit

    ].

    device synchronizeOutput

!

nextPutAll:something

    "this allows TextCollectors to be used Stream-wise"

    ^ self nextPut:something

!

cr

    "output a carriage return, finishing the current line"

    collecting ifTrue:[

	access critical:[

	    outstandingLine notNil ifTrue:[

		outstandingLines add:outstandingLine.

	    ].

	    outstandingLine := ''.

	].

	flushPending ifFalse:[

	    self installDelayedUpdate

	]

    ] ifFalse:[

	access critical:[

	    self cursorReturn.

	    self checkLineLimit.

	].

    ]

!

show:anObject

    "insert the argument aString at current cursor position"

    aString := anObject printString.

    collecting ifTrue:[

	access critical:[

	    outstandingLine notNil ifTrue:[

		outstandingLine := outstandingLine , aString

	    ] ifFalse:[

		outstandingLine := aString

	    ].

	].

	flushPending ifFalse:[

	    self installDelayedUpdate

	]

    ] ifFalse:[

	access critical:[

	    self nextPut:aString.

	].

    ]

!

showCr:aString

    "insert the argument aString followed by a newline

     at current cursor position"

    self show:aString.

    self cr

!

doesNotUnderstand:aMessage

    "this is funny: all message we do not understand, are passed

     on to the stream which will send the characters via nextPut:

     This way, we understand all Stream messages - great isn't it !!

    "

     ^ entryStream perform:(aMessage selector) withArguments:(aMessage arguments)

! !