/* 

 * Copyright (c) 2017-now Jan Vrany

 * 

 * Permission is hereby granted, free of charge, to any person obtaining

 * a copy of this software and associated documentation files (the

 * "Software"), to deal in the Software without restriction, including

 * without limitation the rights to use, copy, modify, merge, publish,

 * distribute, sublicense, and/or sell copies of the Software, and to

 * permit persons to whom the Software is furnished to do so, subject to

 * the following conditions:

 * 

 * The above copyright notice and this permission notice shall be

 * included in all copies or substantial portions of the Software.

 * 

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

 * MeERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.

 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY

 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,

 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE

 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

 */

/*

 * Definition of XKeysymToUnicode(). To be included in X11 client code

 */

#ifndef _XKEYSYMTOUNICODE_H_

#define _XKEYSYMTOUNICODE_H_

#include "xkeysymtounicodetable.h"

/**

 * The `XKeysymToUnicode` function translates given `KeySym` to corresponding

 * Unicode code point. If given `KeySym` has no codepoint associated (for 

 * example,`XK_Num_Lock` or `XK_Left`) then 0 (zero) is returned.  

 */

static uint16_t XKeysymToUnicode(KeySym ks) {

    /*

     * Luckily, for some most commonly used characters (more or less ASCII ones) 

     * the `KeySym` value is the same as its Unicode codepoint. For these we dont

     * need to bother looking them up. This speeds up this function in common 

     * cases.

     */

    if ( (XKEYSYMTOUNICODE_DIRECT_LO <= ks) && (ks <= XKEYSYMTOUNICODE_DIRECT_HI) ) {

        return (uint16_t)ks;

    } else {

        /*

         * So the `KeySym` value is different from its Unicode codepoint.

         * Do a binary search in the table...

         */

        int first = 0;

        int last = xkeysymtounicode_table_size - 1;

        int middle;

        while ( first <= last ) {

            middle = (first + last) / 2;        

            if ( xkeysymtounicode_table[middle].keysym < ks) {

                first = middle + 1;

            } else if ( xkeysymtounicode_table[middle].keysym > ks) {

                last = middle - 1;                

            } else {

                return xkeysymtounicode_table[middle].codepoint;

            }

        }

        /* 

         * If not found, retrun 0 to indicate there's no Unicode character

         * associated with given `KeySym` (such as `XK_Num_Lock` and alike)  

         */

        return (uint16_t)0;

    }

}

#endif//_XKEYSYMTOUNICODE_H_