MacHack 1993/MacHack 1993.toast/MacHack™ 1987-1992/MacHack™ '90/Source Code ƒ/Misc. Pascal ƒ/Jay's Cookie/CookieEdit.p

Text File | 1990-06-15 | 40.9 KB | 1,390 lines | [TEXT/MPS ]

{
    CookieEdit.p -- A simple editor for my fortune files

    Programmer:
        D. Jay Newman

    Date:
        8/3/89

    Notes:
        Skeliton based on the MPW Example TESample.p.  This is released into the
        public domain (at least my code is).
}

PROGRAM CookieEdit;


{

    Edit File

        This program edits a file which consists of (1) a LONGINT which gives the
        total number of fortune cookies, (2) a number of LONGINT offsets to the cookies,
        equal to n + 1 (the last marks the byte after the end of the last cookie), and
        (3) the text of the cookies themselves, with no dividing characters between them.
        The offsets of the cookies in (2) start from the beginning of the cookie text (3);
        that is, the first cookie begins at offset 0.
}

{$D+}

USES
    MemTypes, QuickDraw, OSIntf, ToolIntf, Traps;


CONST

    kTextMargin                = 2;        {Number of pixels to leave around border}

    kMaxOpenDocuments        = 1;        {Maximum number of open documents}

    kMinDocDim                = 64;        {Minimum dimension of window for GrowWindow}

    kControlInvisible        = 0;        {Make control invisible}
    kControlVisible            = $FF;        {Make control visible again}

    kScrollbarWidth            = 16;        {Width of scroll bar, in pixels}
    kScrollbarAdjust        = kScrollbarWidth - 1;
                                        {Used for adjusting things}

    kScrollTweek            = 2;        {Used to have borders coincide}

    kCRChar                    = 13;        {Carriage return}
    kDelChar                = 8;        {Delete}

    kMaxTELength            = 32000;    {Max number of chars in TERec}

    kSysEnvironsVersion        = 1;        {Which version of SysEnvirons we understand}

  {    Event constants}
    kOSEvent                = app4Evt;    {event used by MultiFinder}
    kSuspendResumeMessage    = 1;        {high byte of suspend/resume event message}
    kResumeMask                = 1;        {bit of message field for resume vs. suspend}
    kMouseMovedMessage        = $FA;        {high byte of mouse-moved event message}


    kMinHeap    = 29 * 1024;            {Minimum heap size to run in}

    kMinSpace    = 20 * 1024;            {Minimum space resulting from PurgeSpace}

  {    Used to set up wide open rectangles and regions}
    kExtremeNeg        = -32768;
    kExtremePos        = 32767 - 1;    {required for old region bug}

    kTESlop            = 1024;            {Extra security when pre-flighting edit commands}

    kErrStrings        = 128;            {Resource ID for error strings (STR#)}

  {    The following are indicies into STR# resources}
    eWrongMachine    = 1;
    eSmallSize        = 2;
    eNoMemory        = 3;
    eNoSpaceCut        = 4;
    eNoCut            = 5;
    eNoCopy            = 6;
    eExceedPaste    = 7;
    eNoSpacePaste    = 8;
    eNoWindow        = 9;
    eExceedChar        = 10;
    eNoPaste        = 11;

  {    The following constants are all resource IDs}
    rMenuBar        = 128;            {Application's menu bar}
    rAboutAlert        = 128;            {About alert}
    rUserAlert        = 129;            {User error alert}
    rDocWindow        = 128;            {Application's window}
    rHScroll        = 129;            {Horizontal scrollbar control}

  {    Menus and their items}
    mApple        = 128;                {Apple menu}
    iAbout        = 1;

    mFile        = 129;                {File menu}
    iNew        = 1;
    iOpen        = 2;
    iClose        = 4;
    iSave        = 5;
    iSaveAs        = 6;
    iQuit        = 12;

    mEdit        = 130;                {Edit menu}
    iUndo        = 1;
    iCut        = 3;
    iCopy        = 4;
    iPaste        = 5;
    iClear        = 6;

    mFind        = 150;
    iFind        = 1;
    iFindSame    = 2;
    iFindSel    = 3;
    iDisplaySel    = 4;
    iReplace    = 6;
    iReplSame    = 7;
    iGotoTop    = 9;
    iGotoBottom    = 10;
    iGotoLine    = 11;

    mFortunes    = 151;
    iNewFortune    = 1;
    iDelFortune    = 2;


TYPE

    CookieOffsetArray    =    ARRAY [0..7999] OF Ptr;

    DocumentRecord        = RECORD
        docWindow:        WindowRecord;
        docTE:            TEHandle;
        docVScroll:        ControlHandle;            {Vertical scrollbar}
        docClik:        ProcPtr;
        currentCookie:    INTEGER;                {The number of the current cookie}
        numCookies:        INTEGER;                {Total number of cookies in file}
        cookOffsets:    ^^CookieOffsetHandle;    {Pointer to array of pointers}
        cookieText:        Handle;
    END;

    DocumentPeek    = ^DocumentRecord;


VAR

    gMac                : SysEnvRec;    {Holds the result of a SysEnvirons call}

    gHasWaitNextEvent    : BOOLEAN;        {Obvious}

    gInBackground        : BOOLEAN;        {Maintained by Initialize and DoEvent}

    gNumDocuments        : INTEGER;        {Maintained by Initialize, DoNew, and DoCloseWindow}


{$S Initialize}
FUNCTION TrapAvailable(tNumber: INTEGER; tType: TrapType): BOOLEAN;

{Check to see if a given trap is implemented. This is only used by the
 Initialize routine in this program, so we put it in the Initialize segment.}

BEGIN
    TrapAvailable := NGetTrapAddress(tNumber, tType) <> GetTrapAddress(_Unimplemented);
END; {TrapAvailable}


{$S Main}
FUNCTION IsDAWindow(window: WindowPtr): BOOLEAN;

{Check if a window belongs to a desk accessory.}

BEGIN
    IF window = NIL THEN
        IsDAWindow := FALSE
    ELSE    {DA windows have negative windowKinds}
        IsDAWindow := WindowPeek(window)^.windowKind < 0;
END; {IsDAWindow}


{Check if a window belongs to the application.}

{$S Main}
FUNCTION IsAppWindow(window: WindowPtr): BOOLEAN;
BEGIN
    IF window = NIL THEN
        IsAppWindow := FALSE
    ELSE    {application windows have non-negative windowKinds}
        IsAppWindow := WindowPeek(window)^.windowKind >= 0;
END; {IsAppWindow}


{Display an alert that tells the user an error occurred, then exit the program.
 This routine is used as an ultimate bail-out for serious errors that prohibit
 the continuation of the application. Errors that do not require the termination
 of the application should be handled in a different manner. Error checking and
 reporting has a place even in the simplest application. The error number is used
 to index an 'STR#' resource so that a relevant message can be displayed.}

{$S Main}
PROCEDURE AlertUser(error: INTEGER);
VAR
    itemHit    : INTEGER;
    message    : Str255;
BEGIN
    SetCursor(arrow);
    GetIndString(message, kErrStrings, error);
    ParamText(message, '', '', '');
    itemHit := Alert(rUserAlert, NIL);
END; {AlertUser}



{return a rectangle that is inset from the portRect by the size of
the scrollbars and a little extra margin.}

{$S Main}
PROCEDURE GetTERect(window: WindowPtr; VAR teRect: Rect);
BEGIN
    teRect := window^.portRect;
    InsetRect(teRect, kTextMargin, kTextMargin);            {adjust for margin}
    teRect.bottom := teRect.bottom - kScrollbarAdjust;    {and for the scrollbars}
    teRect.right := teRect.right - kScrollbarAdjust;
END; {GetTERect}



{Close a window. This handles desk accessory and application windows.}

{ 1.01 - At this point, if there was a document associated with a
 window, you could do any document saving processing if it is 'dirty'.
 DoCloseWindow would return TRUE if the window actually closed, i.e.,
 the user didn’t cancel from a save dialog. This result is handy when
 the user quits an application, but then cancels the save of a document
 associated with a window.}

{$S Main}
FUNCTION DoCloseWindow(window: WindowPtr) : BOOLEAN;
BEGIN
    DoCloseWindow := TRUE;
    IF IsDAWindow(window) THEN
        CloseDeskAcc(WindowPeek(window)^.windowKind)
    ELSE IF IsAppWindow(window) THEN BEGIN
        WITH DocumentPeek(window)^ DO
            IF docTE <> NIL THEN
                TEDispose(docTE);        {dispose the TEHandle}
        DisposeWindow(window);
        gNumDocuments := gNumDocuments - 1;
    END;
END; {DoCloseWindow}


{$S Main}
PROCEDURE AdjustViewRect(docTE: TEHandle);

{Update the TERec's view rect so that it is the greatest multiple of
the lineHeight and still fits in the old viewRect.}

BEGIN
    WITH docTE^^ DO BEGIN
        viewRect.bottom := (((viewRect.bottom - viewRect.top) DIV lineHeight) *
                            lineHeight) + viewRect.top;
    END;
END; {AdjustViewRect}


{$S Main}
PROCEDURE AdjustTE(window: WindowPtr);

{Scroll the TERec around to match up to the potentially updated scrollbar
values. This is really useful when the window resizes such that the
scrollbars become inactive and the TERec had been previously scrolled.}

VAR
    value    : INTEGER;
BEGIN
    WITH DocumentPeek(window)^ DO BEGIN
        TEScroll((docTE^^.viewRect.left - docTE^^.destRect.left) - GetCtlValue(docHScroll),
                (docTE^^.viewRect.top - docTE^^.destRect.top) -
                    (GetCtlValue(docVScroll) * docTE^^.lineHeight),
                docTE);
    END;
END; {AdjustTE}


{$S Main}
PROCEDURE AdjustHV(isVert: BOOLEAN; control: ControlHandle; docTE: TEHandle; canRedraw: BOOLEAN);

{Calculate the new control maximum value and current value, whether it is the horizontal or
vertical scrollbar. The vertical max is calculated by comparing the number of lines to the
vertical size of the viewRect. The horizontal max is calculated by comparing the maximum document
width to the width of the viewRect. The current values are set by comparing the offset between
the view and destination rects. If necessary and we canRedraw, have the control be re-drawn by
calling ShowControl.}

VAR
    value, lines, max    : INTEGER;
    oldValue, oldMax    : INTEGER;
BEGIN
    oldValue := GetCtlValue(control);
    oldMax := GetCtlMax(control);
    IF isVert THEN BEGIN
        lines := docTE^^.nLines;
        {since nLines isn’t right if the last character is a return, check for that case}
        IF Ptr(ORD(docTE^^.hText^) + docTE^^.teLength - 1)^ = kCRChar THEN
            lines := lines + 1;
        max := lines - ((docTE^^.viewRect.bottom - docTE^^.viewRect.top) DIV docTE^^.lineHeight);
    END ELSE
        max := kMaxDocWidth - (docTE^^.viewRect.right - docTE^^.viewRect.left);
    IF max < 0 THEN max := 0;            {check for negative values}
    SetCtlMax(control, max);
    IF isVert THEN
        value := (docTE^^.viewRect.top - docTE^^.destRect.top) DIV docTE^^.lineHeight
    ELSE
        value := docTE^^.viewRect.left - docTE^^.destRect.left;
    IF value < 0 THEN
        value := 0
    ELSE IF value > max THEN
        value := max;                    {pin the value to within range}
    SetCtlValue(control, value);
    IF canRedraw & ( (max <> oldMax) | (value <> oldValue) ) THEN
        ShowControl(control);            {check to see if the control can be re-drawn}
END; {AdjustHV}


{$S Main}
PROCEDURE AdjustScrollValues(window: WindowPtr; canRedraw: BOOLEAN);

{Simply call the common adjust routine for the vertical and horizontal scrollbars.}

BEGIN
    WITH DocumentPeek(window)^ DO BEGIN
        AdjustHV(TRUE, docVScroll, docTE, canRedraw);
        AdjustHV(FALSE, docHScroll, docTE, canRedraw);
    END;
END; {AdjustScrollValues}


{$S Main}
PROCEDURE AdjustScrollSizes(window: WindowPtr);

{Re-calculate the position and size of the viewRect and the scrollbars.
 kScrollTweek compensates for off-by-one requirements of the scrollbars
 to have borders coincide with the growbox.}

VAR
    teRect    : Rect;
BEGIN
    GetTERect(window, teRect);                                        {start with teRect}
    WITH DocumentPeek(window)^, window^.portRect DO BEGIN
        docTE^^.viewRect := teRect;
        AdjustViewRect(docTE);                                        {snap to nearest line}
        MoveControl(docVScroll, right - kScrollbarAdjust, -1);
        SizeControl(docVScroll, kScrollbarWidth, (bottom - top) -
                        (kScrollbarAdjust - kScrollTweek));
        MoveControl(docHScroll, -1, bottom - kScrollbarAdjust);
        SizeControl(docHScroll, (right - left) - (kScrollbarAdjust -
                        kScrollTweek), kScrollbarWidth);
    END;
END; {AdjustScrollSizes}


{$S Main}
PROCEDURE AdjustScrollbars(window: WindowPtr; needsResize: BOOLEAN);

{Turn off the controls by jamming a zero into their contrlVis fields (HideControl erases them
and we don't want that). If the controls are to be resized as well, call the procedure to do that,
then call the procedure to adjust the maximum and current values. Finally re-enable the controls
by jamming a $FF in their contrlVis fields.}

VAR
    oldMax, oldVal    : INTEGER;
BEGIN
    WITH DocumentPeek(window)^ DO BEGIN
        {First, turn visibility of scrollbars off so we won’t get unwanted redrawing}
        docVScroll^^.contrlVis := kControlInvisible;    {turn them off}
        docHScroll^^.contrlVis := kControlInvisible;
        IF needsResize THEN                                {move and size if needed}
            AdjustScrollSizes(window);
        AdjustScrollValues(window, NOT needsResize);    {fool with max and current value}
        {Now, restore visibility in case we never had to ShowControl during adjustment}
        docVScroll^^.contrlVis := kControlVisible;        {turn them on}
        docHScroll^^.contrlVis := kControlVisible;
    END;
END; {AdjustScrollbars}


{$S Main}
{$PUSH} {$Z+}
PROCEDURE PascalClikLoop;

{Gets called from our assembly language routine, AsmClikLoop, which is in
 turn called by the TEClick toolbox routine. Saves the windows clip region,
 sets it to the portRect, adjusts the scrollbar values to match the TE scroll
 amount, then restores the clip region.}

VAR
    window    : WindowPtr;
    region    : RgnHandle;
BEGIN
    window := FrontWindow;
    region := NewRgn;
    GetClip(region);                    {save the old clip}
    ClipRect(window^.portRect);            {set the new clip}
    AdjustScrollValues(window, TRUE);    {pass TRUE for canRedraw}
    SetClip(region);                    {restore the old clip}
    DisposeRgn(region);
END; {PascalClikLoop}
{$POP}


{$S Main}
{$PUSH} {$Z+}
FUNCTION GetOldClikLoop : ProcPtr;

{Gets called from our assembly language routine, AsmClikLoop, which is in
turn called by the TEClick toolbox routine. It returns the address of the
default clikLoop routine that was put into the TERec by TEAutoView to
AsmClikLoop so that it can call it.}

BEGIN
    GetOldClikLoop := DocumentPeek(FrontWindow)^.docClik;
END; {GetOldClikLoop}
{$POP}


PROCEDURE AsmClikLoop; EXTERNAL;

{A reference to our assembly language routine that gets attached to the clikLoop
field of our TE record.}


{$S Main}
PROCEDURE DoNew;

{Create a new document and window.}

VAR
    good, ignore        : BOOLEAN;
    storage                : Ptr;
    window                : WindowPtr;
    destRect, viewRect    : Rect;

BEGIN
    storage := NewPtr(SIZEOF(DocumentRecord));
    IF storage <> NIL THEN BEGIN
        window := GetNewWindow(rDocWindow, storage, WindowPtr(-1));
        IF window <> NIL THEN BEGIN
            gNumDocuments := gNumDocuments + 1;    {this will be decremented when we call DoCloseWindow}
            good := FALSE;
            SetPort(window);
            WITH window^, DocumentPeek(window)^ DO BEGIN
                GetTERect(window, viewRect);
                destRect := viewRect;
                destRect.right := destRect.left + kMaxDocWidth;
                docTE := TENew(destRect, viewRect);
                AdjustViewRect(docTE);
                TEAutoView(TRUE, docTE);
                docClik := docTE^^.clikLoop;
                docTE^^.clikLoop := @AsmClikLoop;
                IF docTE <> NIL THEN
                    good := TRUE;                {if TENew succeeded, we have a good document}
                IF good THEN BEGIN
                    docVScroll := GetNewControl(rVScroll, window);
                    good := (docVScroll <> NIL);
                END;
                IF good THEN BEGIN
                    docHScroll := GetNewControl(rHScroll, window);
                    good := (docHScroll <> NIL);
                END;
                IF good THEN BEGIN
                    {FALSE to AdjustScrollValues means musn’t redraw; technically, of course,
                    the window is hidden so it wouldn’t matter whether we called ShowControl or not.}
                    AdjustScrollValues(window, FALSE);
                    ShowWindow(window);            {if the document is good, make the window visible}
                END ELSE BEGIN
                    ignore := DoCloseWindow(window);    {otherwise regret we ever created it...}
                    AlertUser(eNoWindow);                {and tell user}
                END
            END;
        END ELSE
            DisposPtr(storage);                    {get rid of the storage if it is never used}
    END;
END; {DoNew}


{$S Main}
PROCEDURE BigBadError(error: INTEGER);
BEGIN
    AlertUser(error);
    ExitToShell;
END;


{$S Initialize}
PROCEDURE Initialize;

{Set up the whole world, including global variables, Toolbox managers,
 menus, and a single blank document.}

{1.01 - The code that used to be part of ForceEnvirons has been moved into
 this module. If an error is detected, instead of merely doing an ExitToShell,
 which leaves the user without much to go on, we call AlertUser, which puts
 up a simple alert that just says an error occurred and then calls ExitToShell.
 Since there is no other cleanup needed at this point if an error is detected,
 this form of error- handling is acceptable. If more sophisticated error recovery
 is needed, an exception mechanism, such as is provided by Signals, can be used.}

VAR
    menuBar                : Handle;
    total, contig        : LongInt;
    ignoreResult        : BOOLEAN;
    event                : EventRecord;
    count, ignoreError    : INTEGER;

    PROCEDURE BigBadError(error: INTEGER);
    BEGIN
        AlertUser(error);
        ExitToShell;
    END;

BEGIN
    gHasWaitNextEvent := TrapAvailable(_WaitNextEvent, ToolTrap);
    gInBackground := FALSE;

    InitGraf(@thePort);
    InitFonts;
    InitWindows;
    InitMenus;
    TEInit;
    InitDialogs(NIL);
    InitCursor;

    {Call MPPOpen and ATPLoad at this point to initialize AppleTalk,
     if you are using it.}
    {NOTE -- It is no longer necessary, and actually unhealthy, to check
     PortBUse and SPConfig before opening AppleTalk. The drivers are capable
     of checking for port availability themselves.}

    {Now this next bit of code may make you toss your cookies, but it is
     necessary to allow the default button of our alert be outlined.}

    FOR count := 1 TO 3 DO
        ignoreResult := GetNextEvent(everyEvent, event);

    {Ignore the error returned from SysEnvirons; even if an error occurred,
     the SysEnvirons glue will fill in the SysEnvRec. You can save a redundant
     call to SysEnvirons by calling it after initializing AppleTalk.}

    ignoreError := SysEnvirons(kSysEnvironsVersion, gMac);

    {Make sure that the machine has at least 128K ROMs. If it doesn't, exit.}

    IF gMac.machineType < 0 THEN BigBadError(eWrongMachine);

    {1.01 - We used to make a check for memory at this point by examining ApplLimit,
     ApplicZone, and StackSpace and comparing that to the minimum size we told
     MultiFinder we needed. This did not work well because it assumed too much about
     the relationship between what we asked MultiFinder for and what we would actually
     get back, as well as how to measure it. Instead, we will use an alternate
     method comprised of two steps.}

    {It is better to first check the size of the application heap against a value
     that you have determined is the smallest heap the application can reasonably
     work in. This number should be derived by examining the size of the heap that
     is actually provided by MultiFinder when the minimum size requested is used.
     The derivation of the minimum size requested from MultiFinder is described
     in Sample.h. The check should be made because the preferred size can end up
     being set smaller than the minimum size by the user. This extra check acts to
     insure that your application is starting from a solid memory foundation.}

    IF ORD(GetApplLimit) - ORD(ApplicZone) < kMinHeap THEN BigBadError(eSmallSize);

    {Next, make sure that enough memory is free for your application to run. It
     is possible for a situation to arise where the heap may have been of required
     size, but a large scrap was loaded which left too little memory. To check for
     this, call PurgeSpace and compare the result with a value that you have determined
     is the minimum amount of free memory your application needs at initialization.
     This number can be derived several different ways. One way that is fairly
     straightforward is to run the application in the minimum size configuration
     as described previously. Call PurgeSpace at initialization and examine the value
     returned. However, you should make sure that this result is not being modified
     by the scrap's presence. You can do that by calling ZeroScrap before calling
     PurgeSpace. Make sure to remove that call before shipping, though.}

    {* ZeroScrap; *}
    PurgeSpace(total, contig);
    IF total < kMinSpace THEN
        IF UnloadScrap <> noErr THEN
            BigBadError(eNoMemory)
        ELSE BEGIN
            PurgeSpace(total, contig);
            IF total < kMinSpace THEN
                BigBadError(eNoMemory);
        END;

    {The extra benefit to waiting until after the Toolbox Managers have been initialized
     to check memory is that we can now give the user an alert to tell her/him what
     happened. Although it is possible that the memory situation could be worsened by
     displaying an alert, MultiFinder would gracefully exit the application with
     an informative alert if memory became critical. Here we are acting more
     in a preventative manner to avoid future disaster from low-memory problems.}

    menuBar := GetNewMBar(rMenuBar);        {read menus into menu bar}
    IF menuBar = NIL THEN
        BigBadError(eNoMemory);
    SetMenuBar(menuBar);                    {install menus}
    DisposHandle(menuBar);
    AddResMenu(GetMHandle(mApple), 'DRVR');    {add DA names to Apple menu}
    DrawMenuBar;

    gNumDocuments := 0;

    {do other initialization here}

    DoNew;                                    {create a single empty document}
END; {Initialize}


(**************************************************************************************
1.01 - PROCEDURE DoCloseBehind(window: WindowPtr); was removed.

{1.01 - DoCloseBehind was a good idea for closing windows when quitting
 and not having to worry about updating the windows, but it suffered
 from a fatal flaw. If a desk accessory owned two windows, it would
 close both those windows when CloseDeskAcc was called. When DoCloseBehind
 got around to calling DoCloseWindow for that other window that was already
 closed, things would go very poorly. Another option would be to have a
 procedure, GetRearWindow, that would go through the window list and return
 the last window. Instead, we decided to present the standard approach
 of getting and closing FrontWindow until FrontWindow returns NIL. This
 has a potential benefit in that the window whose document needs to be saved
 may be visible since it is the front window, therefore decreasing the
 chance of user confusion. For aesthetic reasons, the windows in the
 application should be checked for updates periodically and have the
 updates serviced.}
**************************************************************************************)


{$S Main}
PROCEDURE Terminate;

{Clean up the application and exit. We close all of the windows so that
 they can update their documents, if any.}

{1.01 - If we find out that a cancel has occurred, we won't exit to the
 shell, but will return instead.}

VAR
    aWindow    : WindowPtr;
    closed    : BOOLEAN;

BEGIN
    closed := TRUE;
    REPEAT
        aWindow := FrontWindow;                    {get the current front window}
        IF aWindow <> NIL THEN
            closed := DoCloseWindow(aWindow);    {close this window}
    UNTIL (NOT closed) | (aWindow = NIL);        {do all windows}
    IF closed THEN
        ExitToShell;                            {exit if no cancellation}
END; {Terminate}


{$S Main}
PROCEDURE AdjustMenus;

{Enable and disable menus based on the current state.
 The user can only select enabled menu items. We set up all the menu items
 before calling MenuSelect or MenuKey, since these are the only times that
 a menu item can be selected. Note that MenuSelect is also the only time
 the user will see menu items. This approach to deciding what enable/
 disable state a menu item has the advantage of concentrating all the decision-
 making in one routine, as opposed to being spread throughout the application.
 Other application designs may take a different approach that may or may not be
 as valid.}

VAR
    window            : WindowPtr;
    menu            : MenuHandle;
    offset            : LONGINT;
    undo            : BOOLEAN;
    cutCopyClear    : BOOLEAN;
    paste            : BOOLEAN;

BEGIN
    window := FrontWindow;

    menu := GetMHandle(mFile);
    IF gNumDocuments < kMaxOpenDocuments THEN
        EnableItem(menu, iNew)        {New is enabled when we can open more documents}
    ELSE
        DisableItem(menu, iNew);
    IF window <> NIL THEN            {Close is enabled when there is a window to close}
        EnableItem(menu, iClose)
    ELSE
        DisableItem(menu, iClose);

    menu := GetMHandle(mEdit);
    undo := FALSE;
    cutCopyClear := FALSE;
    paste := FALSE;
    IF IsDAWindow(window) THEN BEGIN
        undo := TRUE;                {all editing is enabled for DA windows}
        cutCopyClear := TRUE;
        paste := TRUE;
    END ELSE IF IsAppWindow(window) THEN BEGIN
        WITH DocumentPeek(window)^.docTE^^ DO
            IF selStart < selEnd THEN
                cutCopyClear := TRUE;
                {Cut, Copy, and Clear is enabled for app. windows with selections}
        IF GetScrap(NIL, 'TEXT', offset) > 0 THEN
            paste := TRUE;            {Paste is enabled for app. windows}
    END;
    IF undo THEN
        EnableItem(menu, iUndo)
    ELSE
        DisableItem(menu, iUndo);
    IF cutCopyClear THEN BEGIN
        EnableItem(menu, iCut);
        EnableItem(menu, iCopy);
        EnableItem(menu, iClear);
    END ELSE BEGIN
        DisableItem(menu, iCut);
        DisableItem(menu, iCopy);
        DisableItem(menu, iClear);
    END;
    IF paste THEN
        EnableItem(menu, iPaste)
    ELSE
        DisableItem(menu, iPaste);
END; {AdjustMenus}


{$S Main}
PROCEDURE DoMenuCommand(menuResult: LONGINT);

{This is called when an item is chosen from the menu bar (after calling
 MenuSelect or MenuKey). It does the right thing for each command.}

VAR
    menuID, menuItem        : INTEGER;
    itemHit, daRefNum        : INTEGER;
    daName                    : Str255;
    ignoreResult, saveErr    : OSErr;
    handledByDA                : BOOLEAN;
    te                        : TEHandle;
    window                    : WindowPtr;
    ignore                    : BOOLEAN;
    aHandle                    : Handle;
    oldSize, newSize        : LongInt;
    total, contig            : LongInt;

BEGIN
    window := FrontWindow;
    menuID := HiWrd(menuResult);    {use built-ins (for efficiency)...}
    menuItem := LoWrd(menuResult);    {to get menu item number and menu number}
    CASE menuID OF

        mApple:
            CASE menuItem OF
                iAbout:                {bring up alert for About}
                    itemHit := Alert(rAboutAlert, NIL);
                OTHERWISE BEGIN        {all non-About items in this menu are DAs}
                    GetItem(GetMHandle(mApple), menuItem, daName);
                    daRefNum := OpenDeskAcc(daName);
                END;
            END;

        mFile:
            CASE menuItem OF
                iNew:
                    DoNew;
                iClose:
                    ignore := DoCloseWindow(window); {we don't care if cancelled}
                iQuit:
                    Terminate;
            END;

        mEdit: BEGIN                {call SystemEdit for DA editing & MultiFinder}
            IF NOT SystemEdit(menuItem-1) THEN BEGIN
                te := DocumentPeek(window)^.docTE;
                CASE menuItem OF

                    iCut: BEGIN        {after cutting, export the TE scrap}
                        IF ZeroScrap = noErr THEN BEGIN
                            PurgeSpace(total, contig);
                            IF (te^^.selEnd - te^^.selStart) + kTESlop > contig THEN
                                AlertUser(eNoSpaceCut)
                            ELSE BEGIN
                                TECut(te);
                                IF TEToScrap <> noErr THEN BEGIN
                                    AlertUser(eNoCut);
                                    ignoreResult := ZeroScrap;
                                END;
                            END;
                        END;
                    END;

                    iCopy: BEGIN    {after copying, export the TE scrap}
                        IF ZeroScrap = noErr THEN BEGIN
                            TECopy(te);
                            IF TEToScrap <> noErr THEN BEGIN
                                AlertUser(eNoCopy);
                                ignoreResult := ZeroScrap;
                            END;
                        END;
                    END;

                    iPaste: BEGIN    {import the TE scrap before pasting}
                        IF TEFromScrap = noErr THEN BEGIN
                            IF TEGetScrapLen + (te^^.teLength -
                                (te^^.selEnd - te^^.selStart)) > kMaxTELength THEN
                                AlertUser(eExceedPaste)
                            ELSE BEGIN
                                    aHandle := Handle(TEGetText(te));
                                    oldSize := GetHandleSize(aHandle);
                                    newSize := oldSize + TEGetScrapLen + kTESlop;
                                    SetHandleSize(aHandle, newSize);
                                    saveErr := MemError;
                                    SetHandleSize(aHandle, oldSize);
                                    IF saveErr <> noErr THEN
                                        AlertUser(eNoSpacePaste)
                                    ELSE
                                        TEPaste(te);
                                END;
                        END ELSE
                            AlertUser(eNoPaste);
                    END;

                    iClear:
                        TEDelete(te);

                END;
                AdjustScrollbars(window, FALSE);
                AdjustTE(window);
            END;
        END;
    END;
    HiliteMenu(0);                    {unhighlight what MenuSelect (or MenuKey) hilited}
END; {DoMenuCommand}


{$S Main}
PROCEDURE DrawWindow(window: WindowPtr);

{Draw the contents of an application window.}

BEGIN
    SetPort(window);
    WITH window^ DO BEGIN
        EraseRect(portRect);        {as per TextEdit chapter of Inside Macintosh}
        DrawControls(window);        {this ordering makes for a better appearance}
        DrawGrowIcon(window);
        TEUpdate(portRect, DocumentPeek(window)^.docTE);
    END;
END; {DrawWindow}


{$S Main}
FUNCTION GetSleep: LONGINT;

{Calculate a sleep value for WaitNextEvent. This takes into account the things
 that DoIdle does with idle time.}

VAR
    sleep    : LONGINT;
    window    : WindowPtr;

BEGIN
    sleep := MAXLONGINT;                    {default value for sleep}
    IF NOT gInBackground THEN BEGIN            {if we are in front...}
        window := FrontWindow;            {and the front window is ours...}
        IF IsAppWindow(window) THEN BEGIN
            WITH DocumentPeek(window)^.docTE^^ DO
                IF selStart = selEnd THEN    {and the selection is an insertion point...}
                    sleep := GetCaretTime;    {we need to blink the insertion point}
        END;
    END;
    GetSleep := sleep;
END; {GetSleep}


{$S Main}
PROCEDURE CommonAction(control: ControlHandle; VAR amount: INTEGER);

{Common algorithm for setting the new value of a control. It returns the actual amount
the value of the control changed. Note the pinning is done for the sake of returning
the amount the control value changed.}

VAR
    value, max    : INTEGER;
    window        : WindowPtr;
BEGIN
    value := GetCtlValue(control);    {get current value}
    max := GetCtlMax(control);        {and max value}
    amount := value - amount;
    IF amount < 0 THEN
        amount := 0
    ELSE IF amount > max THEN
        amount := max;
    SetCtlValue(control, amount);
    amount := value - amount;        {calculate true change}
END; {CommonAction}


{$S Main}
PROCEDURE VActionProc(control: ControlHandle; part: INTEGER);

{Determines how much to change the value of the vertical scrollbar by and how
much to scroll the TE record.}

VAR
    amount    : INTEGER;
    window    : WindowPtr;
BEGIN
    IF part <> 0 THEN BEGIN
        window := control^^.contrlOwner;
        WITH DocumentPeek(window)^, DocumentPeek(window)^.docTE^^ DO BEGIN
            CASE part OF
                inUpButton, inDownButton:
                    amount := 1;                                                {one line}
                inPageUp, inPageDown:
                    amount := (viewRect.bottom - viewRect.top) DIV lineHeight;    {one page}
            END;
            IF (part = inDownButton) | (part = inPageDown) THEN
                amount := -amount;                                                {reverse direction}
            CommonAction(control, amount);
            IF amount <> 0 THEN
                TEScroll(0, amount * docTE^^.lineHeight, docTE);
        END;
    END;
END; {VActionProc}


{$S Main}
PROCEDURE HActionProc(control: ControlHandle; part: INTEGER);

{Determines how much to change the value of the horizontal scrollbar by and how
much to scroll the TE record.}

VAR
    amount    : INTEGER;
    window    : WindowPtr;
BEGIN
    IF part <> 0 THEN BEGIN
        window := control^^.contrlOwner;
        WITH DocumentPeek(window)^, DocumentPeek(window)^.docTE^^ DO BEGIN
            CASE part OF
                inUpButton, inDownButton:                                        {a few pixels}
                    amount := kButtonScroll;
                inPageUp, inPageDown:
                    amount := viewRect.right - viewRect.left;                    {a page}
            END;
            IF (part = inDownButton) | (part = inPageDown) THEN
                amount := -amount;                                                {reverse direction}
            CommonAction(control, amount);
            IF amount <> 0 THEN
                TEScroll(amount, 0, docTE);
        END;
    END;
END; {HActionProc}


{$S Main}
PROCEDURE DoIdle;

{This is called whenever we get an null event or a mouse-moved event.
 It takes care of necessary periodic actions. For this program, it calls TEIdle.}

VAR
    window    : WindowPtr;

BEGIN
    window := FrontWindow;
    IF IsAppWindow(window) THEN
        TEIdle(DocumentPeek(window)^.docTE);
END; {DoIdle}


{$S Main}
PROCEDURE DoKeyDown(event: EventRecord);

{This is called for any keyDown or autoKey events, except when the
 Command key is held down. It looks at the frontmost window to decide what
 to do with the key typed.}

VAR
    window    : WindowPtr;
    key        : CHAR;
    te        : TEHandle;

BEGIN
    window := FrontWindow;
    IF IsAppWindow(window) THEN BEGIN
        te := DocumentPeek(window)^.docTE;
        key := CHR(BAnd(event.message, charCodeMask));
        IF (key = CHR(kDelChar)) |                            {don't count deletes}
            (te^^.teLength - (te^^.selEnd - te^^.selStart)
                            + 1 < kMaxTELength) THEN BEGIN    {but check haven't gone past}
            TEKey(key, te);
            AdjustScrollbars(window, FALSE);
            AdjustTE(window);
        END ELSE
            AlertUser(eExceedChar);
    END;
END; {DoKeyDown}


{$S Main}
PROCEDURE DoContentClick(window: WindowPtr; event: EventRecord);

{Called when a mouseDown occurs in the content of a window.}

VAR
    mouse        : Point;
    control        : ControlHandle;
    part, value    : INTEGER;
    shiftDown    : BOOLEAN;
    teRect        : Rect;

BEGIN
    IF IsAppWindow(window) THEN BEGIN
        SetPort(window);
        mouse := event.where;                                            {get the click position}
        GlobalToLocal(mouse);                                            {convert to local coordinates}
        {see if we are in the viewRect. if so, we won’t check the controls}
        GetTERect(window, teRect);
        IF PtInRect(mouse, teRect) THEN BEGIN
            shiftDown := BAnd(event.modifiers, shiftKey) <> 0;    {extend if Shift is down}
            TEClick(mouse, shiftDown, DocumentPeek(window)^.docTE);
        END ELSE BEGIN
            part := FindControl(mouse, window, control);
            WITH DocumentPeek(window)^ DO
                CASE part OF
                    0:;                                            {do nothing for viewRect case}
                    inThumb: BEGIN
                        value := GetCtlValue(control);
                        part := TrackControl(control, mouse, NIL);
                        IF part <> 0 THEN BEGIN
                            value := value - GetCtlValue(control);
                            IF value <> 0 THEN
                                IF control = docVScroll THEN
                                    TEScroll(0, value * docTE^^.lineHeight, docTE)
                                ELSE
                                    TEScroll(value, 0, docTE);
                        END;
                    END;
                    OTHERWISE                                    {must be page or button}
                        IF control = docVScroll THEN
                            value := TrackControl(control, mouse, @VActionProc)
                        ELSE
                            value := TrackControl(control, mouse, @HActionProc);
                END;
        END;
    END;
END; {DoContentClick}


{$S Main}
PROCEDURE ResizeWindow(window: WindowPtr);

{Called when the window has been resized to fix up the controls and content}

BEGIN
    WITH window^ DO BEGIN
        AdjustScrollbars(window, TRUE);
        AdjustTE(window);
        InvalRect(portRect);
    END;
END; {ResizeWindow}


{$S Main}
PROCEDURE GetLocalUpdateRgn(window: WindowPtr; localRgn: RgnHandle);

{Returns the update region in local coordinates}

BEGIN
    CopyRgn(WindowPeek(window)^.updateRgn, localRgn);                        {save old update region}
    WITH window^.portBits.bounds DO
        OffsetRgn(localRgn, left, top);                                        {convert to local coords}
END; {GetLocalUpdateRgn}


{$S Main}
PROCEDURE DoGrowWindow(window: WindowPtr; event: EventRecord);

{Called when a mouseDown occurs in the grow box of an active window. In
 order to eliminate any 'flicker', we want to invalidate only what is
 necessary. Since ResizeWindow invalidates the whole portRect, we save
 the old TE viewRect, intersect it with the new TE viewRect, and
 remove the result from the update region. However, we must make sure
 that any old update region that might have been around gets put back.}

VAR
    growResult        : LONGINT;
    tempRect        : Rect;
    tempRgn            : RgnHandle;
    ignoreResult    : BOOLEAN;

BEGIN
    WITH screenBits.bounds DO
        SetRect(tempRect, kMinDocDim, kMinDocDim, right, bottom);            {set up limiting values}
    growResult := GrowWindow(window, event.where, tempRect);
    IF growResult <> 0 THEN                                                 {see if changed size}
        WITH DocumentPeek(window)^, window^ DO BEGIN
            tempRect := docTE^^.viewRect;                                    {save old text box}
            tempRgn := NewRgn;
            GetLocalUpdateRgn(window, tempRgn);                                {get localized update region}
            SizeWindow(window, LoWrd(growResult), HiWrd(growResult), TRUE);
            ResizeWindow(window);
            ignoreResult := SectRect(tempRect, docTE^^.viewRect, tempRect);    {find what stayed same}
            ValidRect(tempRect);                                            {take it out of update}
            InvalRgn(tempRgn);                                                {put back any prior update}
            DisposeRgn(tempRgn);
        END;
END; {DoGrowWindow}


{$S Main}
PROCEDURE DoZoomWindow(window: WindowPtr; part: INTEGER);

{Called when a mouseClick occurs in the zoom box of an active window.
 Everything has to get re-drawn here, so we don't mind that
 ResizeWindow invalidates the whole portRect.}

BEGIN
    WITH window^ DO BEGIN
        EraseRect(portRect);
        ZoomWindow(window, part, (window = FrontWindow));
        ResizeWindow(window);
    END;
END; {DoZoomWindow}


{$S Main}
PROCEDURE DoUpdate(window: WindowPtr);

{This is called when an update event is received for a window.
 It calls DrawWindow to draw the contents of an application window,
 but only if the visRgn is non-empty; for efficiency reasons,
 not because it is required.}

BEGIN
    IF IsAppWindow(window) THEN BEGIN
        BeginUpdate(window);                    {this sets up the visRgn}
        IF NOT EmptyRgn(window^.visRgn) THEN    {draw if updating needs to be done}
            DrawWindow(window);
        EndUpdate(window);
    END;
END; {DoUpdate}


{$S Main}
PROCEDURE DoActivate(window: WindowPtr; becomingActive: BOOLEAN);

{This is called when a window is activated or deactivated.}

VAR
    tempRgn, clipRgn    : RgnHandle;
    growRect            : Rect;

BEGIN
    IF IsAppWindow(window) THEN
        WITH DocumentPeek(window)^ DO
            IF becomingActive THEN BEGIN
                {since we don’t want TEActivate to draw a selection in an area where
                 we’re going to erase and redraw, we’ll clip out the update region
                 before calling it.}
                tempRgn := NewRgn;
                clipRgn := NewRgn;
                GetLocalUpdateRgn(window, tempRgn);            {get localized update region}
                GetClip(clipRgn);
                DiffRgn(clipRgn, tempRgn, tempRgn);            {subtract updateRgn from clipRgn}
                SetClip(tempRgn);
                TEActivate(docTE);                            {let TE do its thing}
                SetClip(clipRgn);                            {restore the full-blown clipRgn}
                DisposeRgn(tempRgn);
                DisposeRgn(clipRgn);

                {the controls need to be redrawn on activation:}
                docVScroll^^.contrlVis := kControlVisible;
                docHScroll^^.contrlVis := kControlVisible;
                InvalRect(docVScroll^^.contrlRect);
                InvalRect(docHScroll^^.contrlRect);
                {the growbox needs to be redrawn on activation:}
                growRect := window^.portRect;
                WITH growRect DO BEGIN
                    top := bottom - kScrollbarAdjust;        {adjust for the scrollbars}
                    left := right - kScrollbarAdjust;
                    END;
                InvalRect(growRect);
            END ELSE BEGIN
                TEDeactivate(docTE);
                {the controls should be hidden immediately on deactivation:}
                HideControl(docVScroll);
                HideControl(docHScroll);
                {the growbox should be changed immediately on deactivation:}
                DrawGrowIcon(window);
            END;
END; {DoActivate}


{$S Main}
PROCEDURE AdjustCursor(mouse: Point; region: RgnHandle);

{Change the cursor's shape, depending on its position. This also calculates a region
 that includes the cursor for WaitNextEvent.}

VAR
    window        : WindowPtr;
    arrowRgn    : RgnHandle;
    iBeamRgn    : RgnHandle;
    iBeamRect    : Rect;

BEGIN
    window := FrontWindow;    {we only adjust the cursor when we are in front}
    IF (NOT gInBackground) AND (NOT IsDAWindow(window)) THEN BEGIN
        {calculate regions for different cursor shapes}
        arrowRgn := NewRgn;
        iBeamRgn := NewRgn;

        {start with a big, big rectangular region}
        SetRectRgn(arrowRgn, kExtremeNeg, kExtremeNeg, kExtremePos, kExtremePos);

        {calculate iBeamRgn}
        IF IsAppWindow(window) THEN BEGIN
            iBeamRect := DocumentPeek(window)^.docTE^^.viewRect;
            SetPort(window);                    {make a global version of the viewRect}
            WITH iBeamRect DO BEGIN
                LocalToGlobal(topLeft);
                LocalToGlobal(botRight);
            END;
            RectRgn(iBeamRgn, iBeamRect);
            WITH window^.portBits.bounds DO
                SetOrigin(-left, -top);
            SectRgn(iBeamRgn, window^.visRgn, iBeamRgn);
            SetOrigin(0, 0);
        END;

        {subtract other regions from arrowRgn}
        DiffRgn(arrowRgn, iBeamRgn, arrowRgn);

        {change the cursor and the region parameter}
        IF PtInRgn(mouse, iBeamRgn) THEN BEGIN
            SetCursor(GetCursor(iBeamCursor)^^);
            CopyRgn(iBeamRgn, region);
        END ELSE BEGIN
            SetCursor(arrow);
            CopyRgn(arrowRgn, region);
        END;

        {get rid of our local regions}
        DisposeRgn(arrowRgn);
        DisposeRgn(iBeamRgn);
    END;
END; {AdjustCursor}


{$S Main}
PROCEDURE DoEvent(event: EventRecord);

{Do the right thing for an event. Determine what kind of event it is, and call
 the appropriate routines.}

VAR
    part    : INTEGER;
    window    : WindowPtr;
    key        : CHAR;
    ignore    : BOOLEAN;

BEGIN
    CASE event.what OF
        nullEvent:
            DoIdle;
        mouseDown: BEGIN
            part := FindWindow(event.where, window);
            CASE part OF
                inMenuBar: BEGIN
                    AdjustMenus;
                    DoMenuCommand(MenuSelect(event.where));
                END;
                inSysWindow:
                    SystemClick(event, window);
                inContent:
                    IF window <> FrontWindow THEN BEGIN
                        SelectWindow(window);
                        {DoEvent(event);}    {use this line for "do first click"}
                    END ELSE
                        DoContentClick(window, event);
                inDrag:
                    DragWindow(window, event.where, screenBits.bounds);
                inGrow:
                    DoGrowWindow(window, event);
                inGoAway:
                    IF TrackGoAway(window, event.where) THEN
                        ignore := DoCloseWindow(window);        {we don't care if cancelled}
                inZoomIn, inZoomOut:
                    IF TrackBox(window, event.where, part) THEN
                        DoZoomWindow(window, part);
            END;
        END;
        keyDown, autoKey: BEGIN
            key := CHR(BAnd(event.message, charCodeMask));
            IF BAnd(event.modifiers, cmdKey) <> 0 THEN BEGIN    {Command key down}
                IF event.what = keyDown THEN BEGIN
                    AdjustMenus;            {enable/disable/check menu items properly}
                    DoMenuCommand(MenuKey(key));
                END;
            END ELSE
                DoKeyDown(event);
        END;                                {call DoActivate with the window and...}
        activateEvt:                        {TRUE for activate, FALSE for deactivate}
            DoActivate(WindowPtr(event.message), BAnd(event.modifiers, activeFlag) <> 0);
        updateEvt:                            {call DoUpdate with the window to update}
            DoUpdate(WindowPtr(event.message));
        kOSEvent:
            CASE BAnd(BRotL(event.message, 8), $FF) OF    {high byte of message}
                kMouseMovedMessage:
                    DoIdle;                    {mouse moved is also an idle event}
                kSuspendResumeMessage: BEGIN
                    gInBackground := BAnd(event.message, kResumeMask) = 0;
                    DoActivate(FrontWindow, NOT gInBackground);
                END;
            END;
    END;
END; {DoEvent}


{$S Main}
PROCEDURE EventLoop;

{Get events forever, and handle them by calling DoEvent.
 Also call AdjustCursor each time through the loop.}

VAR
    cursorRgn        : RgnHandle;
    gotEvent        : BOOLEAN;
    event            : EventRecord;

BEGIN
    cursorRgn := NewRgn;        {we'll pass an empty region to WNE the first time thru}
    REPEAT
        IF gHasWaitNextEvent THEN
            gotEvent := WaitNextEvent(everyEvent, event, GetSleep, cursorRgn)
        ELSE BEGIN
            SystemTask;
            gotEvent := GetNextEvent(everyEvent, event);
        END;
        IF gotEvent THEN BEGIN
            AdjustCursor(event.where, cursorRgn);
            DoEvent(event);
            END
        ELSE
            DoIdle;
        AdjustCursor(event.where, cursorRgn);
    UNTIL FALSE;    {loop forever}
END; {EventLoop}


PROCEDURE _DataInit; EXTERNAL;

{This routine is automatically linked in by the MPW Linker. This external
 reference to it is done so that we can unload its segment, %A5Init.}


{$S Main}
BEGIN
    UnloadSeg(@_DataInit);    {note that _DataInit must not be in Main!}

    {1.01 - call to ForceEnvirons removed}
    {If you have stack requirements that differ from the default,
     then you could use SetApplLimit to increase StackSpace at
     this point, before calling MaxApplZone.}

    MaxApplZone;            {expand the heap so code segments load at the top}

    Initialize;                {initialize the program}
    UnloadSeg(@Initialize);    {note that Initialize must not be in Main!}

    EventLoop;                {call the main event loop}
END.