/*
 * tkMacOSXClipboard.c --
 *
 *         This file manages the clipboard for the Tk toolkit.
 *
 * Copyright (c) 1995-1997 Sun Microsystems, Inc.
 * Copyright 2001, Apple Computer, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tkMacOSXClipboard.c,v 1.2 2002/08/31 06:12:29 das Exp $
 */

#include "tkInt.h"
#include "tkPort.h"
#include "tkMacOSXInt.h"
#include "tkSelect.h"

#include <Carbon/Carbon.h>


/*
 *----------------------------------------------------------------------
 *
 * TkSelGetSelection --
 *
 *        Retrieve the specified selection from another process.  For
 *        now, only fetching XA_STRING from CLIPBOARD is supported.
 *        Eventually other types should be allowed.
 * 
 * Results:
 *        The return value is a standard Tcl return value.
 *        If an error occurs (such as no selection exists)
 *        then an error message is left in the interp's result.
 *
 * Side effects:
 *        None.
 *
 *----------------------------------------------------------------------
 */

int
TkSelGetSelection(
    Tcl_Interp *interp,                /* Interpreter to use for reporting
                                 * errors. */
    Tk_Window tkwin,                /* Window on whose behalf to retrieve
                                 * the selection (determines display
                                 * from which to retrieve). */
    Atom selection,                /* Selection to retrieve. */
    Atom target,                /* Desired form in which selection
                                 * is to be returned. */
    Tk_GetSelProc *proc,        /* Procedure to call to process the
                                 * selection, once it has been retrieved. */
    ClientData clientData)        /* Arbitrary value to pass to proc. */
{
    int result;
    int err;
    long length;
    ScrapRef scrapRef;
    char * buf;

    if ((selection == Tk_InternAtom(tkwin, "CLIPBOARD"))
            && (target == XA_STRING)) {
        /* 
         * Get the scrap from the Macintosh global clipboard.
         */
         
        err=GetCurrentScrap(&scrapRef);
        if (err != noErr) {
            Tcl_AppendResult(interp, Tk_GetAtomName(tkwin, selection),
                " GetCurrentScrap failed.", (char *) NULL);
            return TCL_ERROR;
        }
        
        err=GetScrapFlavorSize(scrapRef,'TEXT',&length);
        if (err != noErr) {
            Tcl_AppendResult(interp, Tk_GetAtomName(tkwin, selection),
                " GetScrapFlavorSize failed.", (char *) NULL);
            return TCL_ERROR;
        }
        if (length > 0) {
            Tcl_DString encodedText;

            buf = (char *)ckalloc(length+1);
	    buf[length] = 0;
	    err = GetScrapFlavorData(scrapRef, 'TEXT', &length, buf);
            if (err != noErr) {
                    Tcl_AppendResult(interp, Tk_GetAtomName(tkwin, selection),
                        " GetScrapFlavorData failed.", (char *) NULL);
                    return TCL_ERROR;
            }

            Tcl_ExternalToUtfDString(TkMacOSXCarbonEncoding, buf, length, 
				     &encodedText);
            result = (*proc)(clientData, interp,
                    Tcl_DStringValue(&encodedText));
            Tcl_DStringFree(&encodedText);

            ckfree(buf);
            return result;
        }
    }
    
    Tcl_AppendResult(interp, Tk_GetAtomName(tkwin, selection),
        " selection doesn't exist or form \"", Tk_GetAtomName(tkwin, target),
        "\" not defined", (char *) NULL);
    return TCL_ERROR;
}

/*
 *----------------------------------------------------------------------
 *
 * TkSetSelectionOwner --
 *
 *        This function claims ownership of the specified selection.
 *        If the selection is CLIPBOARD, then we empty the system
 *        clipboard.
 *
 * Results:
 *        None.
 *
 * Side effects:
 *        None.
 *
 *----------------------------------------------------------------------
 */

void
XSetSelectionOwner(
    Display* display,        /* X Display. */
    Atom selection,        /* What selection to own. */
    Window owner,        /* Window to be the owner. */
    Time time)                /* The current time? */
{
    Tk_Window tkwin;
    TkDisplay *dispPtr;

    /*
     * This is a gross hack because the Tk_InternAtom interface is broken.
     * It expects a Tk_Window, even though it only needs a Tk_Display.
     */

    tkwin = (Tk_Window) TkGetMainInfoList()->winPtr;

    if (selection == Tk_InternAtom(tkwin, "CLIPBOARD")) {

        /*
         * Only claim and empty the clipboard if we aren't already the
         * owner of the clipboard.
         */

        dispPtr = TkGetMainInfoList()->winPtr->dispPtr;
        if (dispPtr->clipboardActive) {
            return;
        }
        ClearCurrentScrap();
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TkSelUpdateClipboard --
 *
 *        This function is called to force the clipboard to be updated
 *        after new data is added.  On the Mac we don't need to do
 *        anything.
 *
 * Results:
 *        None.
 *
 * Side effects:
 *        None.
 *
 *----------------------------------------------------------------------
 */

void
TkSelUpdateClipboard(
    TkWindow *winPtr,                        /* Window associated with clipboard. */
    TkClipboardTarget *targetPtr)        /* Info about the content. */
{
}

/*
 *--------------------------------------------------------------
 *
 * TkSelEventProc --
 *
 *        This procedure is invoked whenever a selection-related
 *        event occurs. 
 *
 * Results:
 *        None.
 *
 * Side effects:
 *        Lots:  depends on the type of event.
 *
 *--------------------------------------------------------------
 */

void
TkSelEventProc(
    Tk_Window tkwin,                /* Window for which event was
                                 * targeted. */
    register XEvent *eventPtr)        /* X event:  either SelectionClear,
                                 * SelectionRequest, or
                                 * SelectionNotify. */
{
    if (eventPtr->type == SelectionClear) {
        TkSelClearSelection(tkwin, eventPtr);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TkSelPropProc --
 *
 *        This procedure is invoked when property-change events
 *        occur on windows not known to the toolkit.  This is a stub
 *        function under Windows.
 *
 * Results:
 *        None.
 *
 * Side effects:
 *        None.
 *
 *----------------------------------------------------------------------
 */

void
TkSelPropProc(
    register XEvent *eventPtr)                /* X PropertyChange event. */
{
}

/*
 *----------------------------------------------------------------------
 *
 * TkSuspendClipboard --
 *
 *        Handle clipboard conversion as required by the suppend event.
 *        This function is also called on exit.
 *
 * Results:
 *        None.
 *
 * Side effects:
 *        The local scrap is moved to the global scrap.
 *
 *----------------------------------------------------------------------
 */

void
TkSuspendClipboard()
{
    TkClipboardTarget *targetPtr;
    TkClipboardBuffer *cbPtr;
    TkDisplay *dispPtr;
    char *buffer, *p, *endPtr, *buffPtr;
    long length;
    ScrapRef scrapRef;

    dispPtr = TkGetDisplayList();
    if ((dispPtr == NULL) || !dispPtr->clipboardActive) {
        return;
    }

    for (targetPtr = dispPtr->clipTargetPtr; targetPtr != NULL;
            targetPtr = targetPtr->nextPtr) {
        if (targetPtr->type == XA_STRING)
            break;
    }
    if (targetPtr != NULL) {
        Tcl_DString encodedText;

        length = 0;
        for (cbPtr = targetPtr->firstBufferPtr; cbPtr != NULL;
                cbPtr = cbPtr->nextPtr) {
            length += cbPtr->length;
        }

        buffer = ckalloc(length);
        buffPtr = buffer;
        for (cbPtr = targetPtr->firstBufferPtr; cbPtr != NULL;
                cbPtr = cbPtr->nextPtr) {
            for (p = cbPtr->buffer, endPtr = p + cbPtr->length;
                    p < endPtr; p++) {
                if (*p == '\n') {
                    *buffPtr++ = '\r';
                } else {
                    *buffPtr++ = *p;
                }
            }
        }

        ClearCurrentScrap();
        GetCurrentScrap(&scrapRef);
        Tcl_UtfToExternalDString(TkMacOSXCarbonEncoding, buffer, length, &encodedText);
        PutScrapFlavor(scrapRef, 'TEXT', 0, Tcl_DStringLength(&encodedText), Tcl_DStringValue(&encodedText) );
        Tcl_DStringFree(&encodedText);
        ckfree(buffer);
    }

    /*
     * The system now owns the scrap.  We tell Tk that it has
     * lost the selection so that it will look for it the next time
     * it needs it.  (Window list NULL if quiting.)
     */

    if (TkGetMainInfoList() != NULL) {
        Tk_ClearSelection((Tk_Window) TkGetMainInfoList()->winPtr, 
                Tk_InternAtom((Tk_Window) TkGetMainInfoList()->winPtr,
                        "CLIPBOARD"));
    }

    return;
}
