#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "libblang.h"

/* assumes unmodified chart */
void Chart_iron(struct State *s){
	chart_t index;
	chart_t lookahead;

	index = s->chart;
	while(*index != '\0'){
		if(*index == ';'){
			lookahead = index;
			while(
					*lookahead != '!'
					&& *lookahead != '\n'
					&& *lookahead != '\0'
			)
				++lookahead;
		}
		++index;
	}
}

void Ops_bang(struct State *s){ return; } /* more like a whimper */
void Ops_land(struct State *s){ return; }

void Ops_snd(struct State *s)	{ *(s->chart) = s->hand; }
void Ops_rcv(struct State *s)	{ s->hand = (hand_t)*(s->chart); }

void Ops_et(struct State *s)	{ s->hand = (hand_t)s->chart; }
void Ops_splat(struct State *s)	{ s->chart = (chart_t)s->hand; }

void Ops_inc(struct State *s)	{ ++(s->hand); }
void Ops_dec(struct State *s)	{ --(s->hand); }
void Ops_invert(struct State *s){ s->hand = !s->hand; }

void Ops_sail(struct State *s)	{
	while(Ops_lookup(*(s->counter)) != Ops_land)
		--*(s->counter);
}

void Ops_in(struct State *s)	{ s->hand = *++s->counter; }
void Ops_out(struct State *s)	{ putc((char)s->hand, stdout); }

void Ops_what(struct State *s)	{ s->counter += !s->hand; }

void Ops_comment(struct State *s){
	while(strchr(BLANG_COMMENT_END, *++s->counter) == NULL);
}

const struct {
	unsigned char name;
	void (*f)(struct State *);
} OPS[] = {
	{ '!', Ops_bang }, { ' ', Ops_bang }, { '\n', Ops_bang },
	{ '\r', Ops_bang }, { '\t', Ops_bang }, { '\v', Ops_bang },
	{ '%', Ops_snd }, { '^', Ops_rcv },
	{ '&', Ops_et }, { '*', Ops_splat },
	{ '+', Ops_inc }, { '-', Ops_dec }, { 'v', Ops_invert },
	{ '{', Ops_land }, { '}', Ops_sail },
	{ '<', Ops_in }, { '>', Ops_out },
	{ '?', Ops_what },
	{ ';', Ops_comment }, { '#', Ops_comment }
};

/* Slower than a switch, but you don't have to update it when you add new
 * ops! */
void (*Ops_lookup(char op))(struct State *){
	size_t i;

	for(i = 0; i < (sizeof OPS)/(sizeof *OPS); ++i)
		if(op == OPS[i].name)
			return OPS[i].f;
	return NULL;
}