%{

#include <stdio.h>

#include "ast.h"
#include "lex-pattern.h"

void yyerror(const char *msg)
{
	fprintf(stderr, "%s\n", msg);
}

%}

%output  "parse-pattern.c"
%defines "parse-pattern.h"

%union {
	long  lval;
	char *sval;
	struct atom  *atom;
	struct repeat repeat;
}

%token END 0 "end of file"

%token T_BADLIT
%token T_NOMEM

%token T_ALPHABETIC
%token T_NUMERIC
%token T_UPPERCASE
%token T_LOWERCASE
%token T_CONTROL
%token T_PUNCTUATION
%token T_EVERYTHING

%token          T_LPAREN  "("
%token          T_RPAREN  ")"
%token          T_COMMA   ","
%token          T_PERIOD  "."
%token <lval>   T_INTEGER
%token <sval>   T_STRING

%type  <atom>   alternation
%type  <atom>   atom
%type  <atom>   input
%type  <atom>   sequence
%type  <atom>   molecule

%type  <repeat> repeat

%%

start:
		input END                     { ast = $1; }
	;

input:
		molecule
	|	input molecule                { $$ = mkatom(&(struct atom) { .type = ATOM_SEQUENCE,   .u = { .children = { $1, $2 } } }); }
	;

molecule:
		repeat sequence               { $$ = mkatom(&(struct atom) { .type = ATOM_REPETITION, .u = { .repeat = { .counts = $1, .child = $2 } } }); }
	;

repeat:
		T_INTEGER T_PERIOD T_INTEGER  { $$ = (struct repeat) { $1, $3 }; }
	|	T_INTEGER T_PERIOD            { $$ = (struct repeat) { $1, -1 }; }
	|	T_PERIOD T_INTEGER            { $$ = (struct repeat) {  0, $2 }; }
	|	T_PERIOD                      { $$ = (struct repeat) {  0, -1 }; }
	|	T_INTEGER                     { $$ = (struct repeat) { $1, $1 }; }
	;

sequence:
		atom
	|	sequence atom                 { $$ = mkatom(&(struct atom) { .type = ATOM_SEQUENCE, .u = { .children = { $1, $2 } } }); }
	;

atom:
		T_ALPHABETIC                  { $$ = mkatom(&(struct atom) { .type = ATOM_ALPHABETIC  }); }
	|	T_NUMERIC                     { $$ = mkatom(&(struct atom) { .type = ATOM_NUMERIC     }); }
	|	T_UPPERCASE                   { $$ = mkatom(&(struct atom) { .type = ATOM_UPPERCASE   }); }
	|	T_LOWERCASE                   { $$ = mkatom(&(struct atom) { .type = ATOM_LOWERCASE   }); }
	|	T_CONTROL                     { $$ = mkatom(&(struct atom) { .type = ATOM_CONTROL     }); }
	|	T_PUNCTUATION                 { $$ = mkatom(&(struct atom) { .type = ATOM_PUNCTUATION }); }
	|	T_EVERYTHING                  { $$ = mkatom(&(struct atom) { .type = ATOM_EVERYTHING  }); }
	|	T_STRING                      { $$ = mkatom(&(struct atom) { .type = ATOM_LITERAL, .u = { .literal = $1 } }); }
	|	T_LPAREN alternation T_RPAREN { $$ = $2; }
	;

alternation:
		molecule
	|	alternation T_COMMA molecule  { $$ = mkatom(&(struct atom) { .type = ATOM_ALTERNATION, .u = { .children = { $1, $3 } } }); }
	;