/*

*******************************************************************************

*

*   Copyright (C) 2003, International Business Machines

*   Corporation and others.  All Rights Reserved.

*

*******************************************************************************

*   file name:  unorm_it.h

*   encoding:   US-ASCII

*   tab size:   8 (not used)

*   indentation:4

*

*   created on: 2003jan21

*   created by: Markus W. Scherer

*/

#ifndef __UNORM_IT_H__

#define __UNORM_IT_H__

#include "unicode/utypes.h"

#if !UCONFIG_NO_COLLATION && !UCONFIG_NO_NORMALIZATION

#include "unicode/uiter.h"

#include "unicode/unorm.h"

/**

 * Normalizing UCharIterator wrapper.

 * This internal API basically duplicates the functionality of the C++ Normalizer

 * but

 * - it actually implements a character iterator (UCharIterator)

 *   with few restrictions (see unorm_setIter())

 * - it supports UCharIterator getState()/setState()

 * - it uses lower-level APIs and buffers more text and states,

 *   hopefully resulting in higher performance

 *

 * Usage example:

 * \code

 * function(UCharIterator *srcIter) {

 *     UNormIterator *uni;

 *     UCharIterator *iter;

 *     UErrorCode errorCode;

 * 

 *     errorCode=U_ZERO_ERROR;

 *     uni=unorm_openIter(&errorCode);

 *     if(U_FAILURE(errorCode)) {

 *         // report error

 *         return;

 *     }

 * 

 *     iter=unorm_setIter(uni, srcIter, UNORM_FCD, &errorCode);

 *     if(U_FAILURE(errorCode)) {

 *         // report error

 *     } else {

 *         // use iter to iterate over the canonically ordered

 *         // version of srcIter's text

 *         uint32_t state;

 * 

 *         ...

 * 

 *         state=uiter_getState(iter);

 *         if(state!=UITER_NO_STATE) {

 *             // use valid state, store it, use iter some more

 *             ...

 * 

 *             // later restore iter to the saved state:

 *             uiter_setState(iter, state, &errorCode);

 * 

 *             ...

 *         }

 * 

 *         ...

 *     }

 *     unorm_closeIter(uni);

 * }

 * \endcode

 *

 * See also the ICU test suites.

 *

 * @internal

 */

struct UNormIterator;

typedef struct UNormIterator UNormIterator;

/**

 * Size of a stack buffer to hold a UNormIterator, see the stackMem parameter

 * of unorm_openIter().

 *

 * @internal

 */

#define UNORM_ITER_SIZE 1024

/**

 * Open a normalizing iterator. Must be closed later.

 * Use unorm_setIter().

 *

 * @param stackMem Pointer to preallocated (stack-allocated) buffer to hold

 *                 the UNormIterator if possible; can be NULL.

 * @param stackMemSize Number of bytes at stackMem; can be 0,

 *                     or should be >= UNORM_ITER_SIZE for a non-NULL stackMem.

 * @param pErrorCode ICU error code

 * @return an allocated and pre-initialized UNormIterator

 * @internal

 */

U_CAPI UNormIterator * U_EXPORT2

unorm_openIter(void *stackMem, int32_t stackMemSize, UErrorCode *pErrorCode);

/**

 * Close a normalizing iterator.

 *

 * @param uni UNormIterator from unorm_openIter()

 * @internal

 */

U_CAPI void U_EXPORT2

unorm_closeIter(UNormIterator *uni);

/**

 * Set a UCharIterator and a normalization mode for the normalizing iterator

 * to wrap. The normalizing iterator will read from the character iterator,

 * normalize the text, and in turn deliver it with its own wrapper UCharIterator

 * interface which it returns.

 *

 * The source iterator remains at its current position through the unorm_setIter()

 * call but will be used and moved as soon as the

 * the returned normalizing iterator is.

 *

 * The returned interface pointer is valid for as long as the normalizing iterator

 * is open and until another unorm_setIter() call is made on it.

 *

 * The normalizing iterator's UCharIterator interface has the following properties:

 * - getIndex() and move() will almost always return UITER_UNKNOWN_INDEX

 * - getState() will return UITER_NO_STATE for unknown states for positions

 *              that are not at normalization boundaries

 *

 * @param uni UNormIterator from unorm_openIter()

 * @param iter The source text UCharIterator to be wrapped. It is aliases into the normalizing iterator.

 *             Must support getState() and setState().

 * @param mode The normalization mode.

 * @param pErrorCode ICU error code

 * @return an alias to the normalizing iterator's UCharIterator interface

 * @internal

 */

U_CAPI UCharIterator * U_EXPORT2

unorm_setIter(UNormIterator *uni, UCharIterator *iter, UNormalizationMode mode, UErrorCode *pErrorCode);

#endif /* uconfig.h switches */

#endif