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#include <stdbool.h>
#include "sok.h"
#define UNUSED(a) ((void) (a))
static bool
sok_solve_step(
sok_ctx_t * const ctx,
sok_cache_t * const cache,
const sok_solve_cbs_t * const cbs,
void * const user_data
) {
// check for success
if (sok_ctx_is_done(ctx)) {
// return success
return true;
}
if (sok_cache_has(cache, ctx)) {
// return failure
return false;
}
// add to cache
if (!sok_cache_add(cache, ctx)) {
if (cbs && cbs->on_error) {
// log error
cbs->on_error("sok_cache_add() failed", user_data);
}
// return failure
return false;
}
if (cbs && cbs->on_step && !cbs->on_step(ctx, user_data)) {
// return failure
return false;
}
/*
* // make sure level is solvable
* if (sok_ctx_is_lost(ctx)) {
* // return failure
* return false;
* }
*/
for (size_t dir = 0; dir < SOK_DIR_LAST; dir++) {
if (!sok_ctx_move(ctx, dir)) {
continue;
}
// recurse, check for success
if (sok_solve_step(ctx, cache, cbs, user_data)) {
// return success
return true;
}
// undo move
if (!sok_ctx_undo(ctx)) {
if (cbs && cbs->on_error) {
// log error
cbs->on_error("sok_ctx_undo() failed", user_data);
}
// return failure
return false;
}
}
// return failure
return false;
}
bool
sok_solve(
sok_ctx_t * const ctx,
const sok_solve_cbs_t * const cbs,
void *user_data
) {
// init cache
sok_cache_t cache;
if (!sok_cache_init(&cache, SOK_CACHE_DEFAULT_CAPACITY)) {
if (cbs && cbs->on_error) {
cbs->on_error("sok_cache_init() failed", user_data);
}
// return failure
return false;
}
// solve
const bool r = sok_solve_step(ctx, &cache, cbs, user_data);
// finalize cache
sok_cache_fini(&cache);
// return result
return r;
}
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