#include "runlevel.h"

#include "log.h"
#include "service.h"

#include <errno.h>
#include <fx/collections/array.h>
#include <fx/collections/hashtable.h>
#include <fx/serial.h>
#include <fx/string.h>
#include <fx/stringstream.h>
#include <magenta/log.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

static struct queue runlevels = QUEUE_INIT;

struct queue *global_runlevels(void)
{
	return &runlevels;
}

static int parse_runlevel_data(fx_object *in, struct runlevel *out)
{
	if (!fx_object_is_type(in, FX_TYPE_HASHTABLE)) {
		return -1;
	}

	const fx_value *runlevel_v = fx_hashtable_get(in, &FX_CSTR("runlevel"));
	if (!runlevel_v || !fx_value_is_type(runlevel_v, FX_TYPE_HASHTABLE)) {
		return -1;
	}
	fx_hashtable *in_runlevel = NULL;
	fx_value_get_object(runlevel_v, &in_runlevel);

	const fx_value *name_v
		= fx_hashtable_get(in_runlevel, &FX_CSTR("name"));
	if (!name_v || !fx_value_is_type(name_v, FX_TYPE_STRING)) {
		return -1;
	}
	fx_string *name = NULL;
	fx_value_get_object(name_v, &name);

	const fx_value *description_v
		= fx_hashtable_get(in_runlevel, &FX_CSTR("description"));
	if (!description_v
	    || !fx_value_is_type(description_v, FX_TYPE_STRING)) {
		return -1;
	}
	fx_string *description = NULL;
	fx_value_get_object(description_v, &description);

	const fx_value *deps_v
		= fx_hashtable_get(in_runlevel, &FX_CSTR("requires"));
	if (deps_v && !fx_value_is_type(deps_v, FX_TYPE_ARRAY)) {
		return -1;
	}
	fx_array *deps = NULL;
	fx_value_get_object(deps_v, &deps);

	int ret = 0;
	size_t dep_count = fx_array_get_size(deps);
	const fx_iterator *it = fx_iterator_begin(deps);
	fx_foreach(dep, it)
	{
		if (!fx_value_is_type(dep, FX_TYPE_STRING)) {
			ret = -1;
			break;
		}
	}
	fx_iterator_unref(it);

	if (ret != 0) {
		return ret;
	}

	out->rl_requires_count = dep_count;
	out->rl_requires = calloc(dep_count, sizeof(char *));
	it = fx_iterator_begin(deps);
	size_t i = 0;
	fx_foreach(dep, it)
	{
		fx_string *str = NULL;
		fx_value_get_object(dep, &str);
		out->rl_requires[i++] = fx_string_steal(str);
	}
	fx_iterator_unref(it);

	out->rl_name = fx_string_steal(name);
	out->rl_description = fx_string_steal(description);

	return 0;
}

int runlevel_load(const char *path, struct runlevel **out)
{
	struct runlevel *rl = malloc(sizeof *rl);
	if (!rl) {
		errno = ENOMEM;
		return -1;
	}

	FILE *fp = fopen(path, "r");
	if (!fp) {
		free(rl);
		return -1;
	}

	fx_stream *in = fx_stream_open_fp(fp);
	fx_serial_ctx *ctx = fx_toml_serial_ctx_create();
	fx_value data;
	fx_result result = fx_serial_ctx_deserialise(ctx, in, &data, 0);
	if (fx_result_is_error(result)) {
		fx_throw(result);
		free(rl);
		errno = EFTYPE;
		return -1;
	}

	if (!fx_value_is_type(&data, FX_TYPE_HASHTABLE)) {
		free(rl);
		errno = EFTYPE;
		return -1;
	}

	if (parse_runlevel_data(data.v_object, rl) != 0) {
		free(rl);
		errno = EFTYPE;
		return -1;
	}

	fx_stream_unref(in);
	fx_value_unset(&data);

	fclose(fp);

	*out = rl;
	return 0;
}

struct runlevel *runlevel_find(const char *name)
{
	struct queue_entry *cur = queue_first(&runlevels);
	while (cur) {
		struct runlevel *rl
			= QUEUE_CONTAINER(struct runlevel, rl_entry, cur);
		if (!strcmp(rl->rl_name, name)) {
			return rl;
		}

		cur = queue_next(cur);
	}

	return NULL;
}

int runlevel_activate(struct runlevel *rl)
{
	for (size_t i = 0; i < rl->rl_requires_count; i++) {
		const char *svc_name = rl->rl_requires[i];
		struct service *svc = service_find(svc_name);
		if (!svc) {
			log_fail("Cannot find service %s.", svc_name);
			return -1;
		}

		int ret = service_start(svc);
		if (ret != 0) {
			return ret;
		}
	}

	log_ok("Reached runlevel %s.", rl->rl_description);
	return 0;
}