%define api.pure full
%locations
%define parse.error verbose
%param { yyscan_t scanner }

%code top {
	#include <stdio.h>
}
%code requires {
	typedef void* yyscan_t;
}
%code {
	int yylex(YYSTYPE *yylvalp, YYLTYPE *yyllocp, yyscan_t scanner);
	int yyerror(YYLTYPE *yyllocp, yyscan_t unused, const char *msg);
}

%union {
	long lval;
	double dval;
	char *sval;
	char cval;
}

%token PROLOG
%token S_TAG_OPEN E_TAG_OPEN TAG_CLOSE EMPTY_TAG_CLOSE
%token <sval> NAME
%token <sval> ATTR
%token <sval> TEXT
%token <lval> INTEGER
%token <dval> DOUBLE
%token DATE;


%%


document: PROLOG element;

elements:
	element
	| elements element
	;

element:
	empty_tag
	| start_tag end_tag
	| start_tag content end_tag
	;

content:
	elements
	| integers
	| doubles
	| DATE
	;

empty_tag:
	S_TAG_OPEN NAME attributes EMPTY_TAG_CLOSE { printf("empty tag: %s\n", $2); }
	;

start_tag:
	S_TAG_OPEN NAME attributes TAG_CLOSE { printf("enter tag: %s\n", $2); }
	;

end_tag:
	E_TAG_OPEN NAME TAG_CLOSE { printf("exit tag: %s\n", $2); }
	;

attributes:
	| attribute
	| attributes attribute;
	;

attribute:
	ATTR '=' '"' TEXT '"' { printf("attribute: %s=%s\n", $1, $4); }
	;


integers:
	INTEGER { printf("%d\n", $1); }
	| integers INTEGER { printf("%d\n", $2); }
	;

doubles:
	DOUBLE { printf("%f\n", $1); }
	| doubles DOUBLE { printf("%f\n", $2); }
	;


%%

int yyerror(YYLTYPE *yyllocp, yyscan_t unused, const char *msg)
{
	fprintf(
		stderr, "[%d:%d]: %s\n",
		yyllocp->first_line, yyllocp->first_column, msg
	);
	return 1;
}