#include "mapping/mappers.h"
#include "lib/mlrutil.h"
#include "containers/sllv.h"

static sllv_t*   mapper_cat_process(lrec_t* pinrec, context_t* pctx, void* pvstate);
static void      mapper_cat_free(void* pvstate);
static mapper_t* mapper_cat_alloc();
static void      mapper_cat_usage(FILE* o, char* argv0, char* verb);
static mapper_t* mapper_cat_parse_cli(int* pargi, int argc, char** argv);

// ----------------------------------------------------------------
mapper_setup_t mapper_cat_setup = {
	.verb = "cat",
	.pusage_func = mapper_cat_usage,
	.pparse_func = mapper_cat_parse_cli
};

// ----------------------------------------------------------------
static sllv_t* mapper_cat_process(lrec_t* pinrec, context_t* pctx, void* pvstate) {
	if (pinrec != NULL)
		return sllv_single(pinrec);
	else
		return sllv_single(NULL);
}

// ----------------------------------------------------------------
static void mapper_cat_free(void* pvstate) {
}

static mapper_t* mapper_cat_alloc() {
	mapper_t* pmapper = mlr_malloc_or_die(sizeof(mapper_t));
	pmapper->pvstate       = NULL;
	pmapper->pprocess_func = mapper_cat_process;
	pmapper->pfree_func    = mapper_cat_free;

	return pmapper;
}

// ----------------------------------------------------------------
static void mapper_cat_usage(FILE* o, char* argv0, char* verb) {
	fprintf(o, "Usage: %s %s\n", argv0, verb);
	fprintf(o, "Passes input records directly to output. Most useful for format conversion.\n");
}
static mapper_t* mapper_cat_parse_cli(int* pargi, int argc, char** argv) {
	if ((argc - *pargi) < 1) {
		mapper_cat_usage(stderr, argv[0], argv[*pargi]);
		return NULL;
	}
	mapper_t* pmapper = mapper_cat_alloc();
	*pargi += 1;
	return pmapper;
}