/********************************************************
 * ch_type package					*
 *							*
 * The class ch_type is used to tell the type of	*
 * various characters.					*
 *							*
 * The main member functions are:			*
 *	is -- True if the character is the indicated	*
 *		type.					*
 *	type -- Return type of character.		*
 ********************************************************/
#include <iostream.h>

#include "ch_type.h"

// Define the type information array
char_type::CHAR_TYPE char_type::type_info[256];	
/********************************************************
 * fill_range -- fill in a range of types for the 	*
 *	character type class				*
 *							*
 * Parameters						*
 *	start, end -- range of items to fill in 	*
 *	type -- type to use for filling			*
 ********************************************************/
void char_type::fill_range(int start, int end, CHAR_TYPE type)
{
    int cur_ch;

    for (cur_ch = start; cur_ch <= end; ++cur_ch) {
	type_info[cur_ch] = type;
    }
}

/*********************************************************
 * char_type::char_type -- initialize the char type table*
 *********************************************************/
char_type::char_type()
{
    fill_range(0, 255, C_WHITE);

    fill_range('A', 'Z', C_ALPHA);
    fill_range('a', 'z', C_ALPHA);
    type_info['_'] = C_ALPHA;

    fill_range('0', '9', C_DIGIT);

    type_info['!'] = C_OPERATOR;
    type_info['#'] = C_OPERATOR;
    type_info['$'] = C_OPERATOR;
    type_info['%'] = C_OPERATOR;
    type_info['^'] = C_OPERATOR;
    type_info['&'] = C_OPERATOR;
    type_info['*'] = C_OPERATOR;
    type_info['-'] = C_OPERATOR;
    type_info['+'] = C_OPERATOR;
    type_info['='] = C_OPERATOR;
    type_info['|'] = C_OPERATOR;
    type_info['~'] = C_OPERATOR;
    type_info[','] = C_OPERATOR;
    type_info[':'] = C_OPERATOR;
    type_info['?'] = C_OPERATOR;
    type_info['.'] = C_OPERATOR;
    type_info['<'] = C_OPERATOR;
    type_info['>'] = C_OPERATOR;

    type_info['/'] = C_SLASH;
    type_info['\n'] = C_NEWLINE;

    type_info['('] = C_L_PAREN;
    type_info[')'] = C_R_PAREN;

    type_info['{'] = C_L_CURLY;
    type_info['}'] = C_R_CURLY;

    type_info['"'] = C_DOUBLE;
    type_info['\''] = C_SINGLE;
}

int char_type::is(int ch, CHAR_TYPE kind)
{
    if (ch == EOF) return (kind == C_EOF);

    switch (kind) {
	case C_HEX_DIGIT:
	    if (type_info[ch] == C_DIGIT)
		return (1);
	    if ((ch >= 'A') && (ch <= 'F')) 
		return (1);
	    if ((ch >= 'a') && (ch <= 'f')) 
		return (1);
	    return (0);
	case C_ALPHA_NUMERIC:
	    return ((type_info[ch] == C_ALPHA) ||
		    (type_info[ch] == C_DIGIT));
	default:
	    return (type_info[ch] == kind);
    }
};

char_type::CHAR_TYPE char_type::type(int ch) {
   if (ch == EOF) return (C_EOF);
   return (type_info[ch]);
}