/*
 * tkMacOSXClipboard.c --
 *
 *	This file manages the clipboard for the Tk toolkit.
 *
 * Copyright (c) 1995-1997 Sun Microsystems, Inc.
 * Copyright 2001, Apple Computer, Inc.
 * Copyright (c) 2006-2007 Daniel A. Steffen <das@users.sourceforge.net>
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 */

#include "tkMacOSXPrivate.h"
#include "tkSelect.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;
    OSStatus 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 = ChkErr(GetCurrentScrap, &scrapRef);
	if (err != noErr) {
	    Tcl_AppendResult(interp, Tk_GetAtomName(tkwin, selection),
		    " GetCurrentScrap failed.", NULL);
	    return TCL_ERROR;
	}

	/*
	 * Try UNICODE first
	 */
	err = ChkErr(GetScrapFlavorSize, scrapRef, kScrapFlavorTypeUnicode,
		&length);
	if (err == noErr && length > 0) {
	    Tcl_DString ds;
	    char *data;

	    buf = (char *) ckalloc(length + 2);
	    buf[length] = 0;
	    buf[length+1] = 0; /* 2-byte unicode null */
	    err = ChkErr(GetScrapFlavorData, scrapRef, kScrapFlavorTypeUnicode,
		    &length, buf);
	    if (err == noErr) {
		Tcl_DStringInit(&ds);
		Tcl_UniCharToUtfDString((Tcl_UniChar *)buf,
			Tcl_UniCharLen((Tcl_UniChar *)buf), &ds);
		for (data = Tcl_DStringValue(&ds); *data != '\0'; data++) {
		    if (*data == '\r') {
			*data = '\n';
		    }
		}
		result = (*proc)(clientData, interp, Tcl_DStringValue(&ds));
		Tcl_DStringFree(&ds);
		ckfree(buf);
		return result;
	    }
	}

	err = ChkErr(GetScrapFlavorSize, scrapRef, 'TEXT', &length);
	if (err != noErr) {
	    Tcl_AppendResult(interp, Tk_GetAtomName(tkwin, selection),
		    " GetScrapFlavorSize failed.", NULL);
	    return TCL_ERROR;
	}
	if (length > 0) {
	    Tcl_DString encodedText;
	    char *data;

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

	    /*
	     * Tcl expects '\n' not '\r' as the line break character.
	     */

	    for (data = buf; *data != '\0'; data++) {
		if (*data == '\r') {
		    *data = '\n';
		}
	    }

	    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", 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.
 *
 *----------------------------------------------------------------------
 */

int
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) {
	    ClearCurrentScrap();
	}
    }
    return Success;
}

/*
 *----------------------------------------------------------------------
 *
 * 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(void)
{
    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, unicodedText;

	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);

	/*
	 * Also put unicode data on scrap.
	 */

	Tcl_DStringInit(&unicodedText);
	Tcl_UtfToUniCharDString(buffer, length, &unicodedText);
	PutScrapFlavor(scrapRef, kScrapFlavorTypeUnicode, 0,
		Tcl_DStringLength(&unicodedText),
		Tcl_DStringValue(&unicodedText));
	Tcl_DStringFree(&unicodedText);

	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;
}
