#include "module_manager_interna.h"

#include "stellar/module_manager.h"
#include "stellar/utils.h"
#include <dlfcn.h>
#include <stdbool.h>
#include <assert.h>


UT_icd module_specs_icd = {sizeof(struct module_specific), NULL, NULL, NULL};

/*******************************************
 * module manager internal API *
 *******************************************/

toml_table_t *toml_parse_file_path(const char *toml_conf_path)
{
	if(toml_conf_path==NULL)return NULL;
    FILE* fp = fopen(toml_conf_path, "r");
	if(fp==NULL)return NULL;
    char errbuf[256];
    toml_table_t* conf = toml_parse_file(fp, errbuf, sizeof(errbuf));
    fclose(fp);	
	if(conf==NULL) fprintf(stderr, "Error parsing toml: %s\n", errbuf);
	return conf;
}	

struct module_specific *module_specs_load(toml_table_t* conf, int *mod_num)
{
	if(conf==NULL|| mod_num==NULL) return NULL;
	*mod_num = 0;
	struct module_specific* mod_spec=NULL;
    toml_array_t* mod_array = toml_array_in(conf, "module");
	if(mod_array==NULL)goto MODULE_SPEC_LOAD_ERROR;
    *mod_num = toml_array_nelem(mod_array);
    mod_spec = CALLOC(struct module_specific, *mod_num);

    for (int i = 0; i < *mod_num; i++) {
        toml_table_t* toml_mod = toml_table_at(mod_array, i);

        const char *path_raw = toml_raw_in(toml_mod, "path");
        const char *init_func_name_raw = toml_raw_in(toml_mod, "init");
        const char *exit_func_name_raw = toml_raw_in(toml_mod, "exit");
        char *path = NULL;
        char *init_func_name = NULL;
        char *exit_func_name = NULL;
        if (toml_rtos(path_raw, &path) || toml_rtos(init_func_name_raw, &init_func_name) ||
            toml_rtos(exit_func_name_raw, &exit_func_name))
        {
            goto MODULE_SPEC_LOAD_ERROR;
        }
        void* handle = dlopen(path, RTLD_NOW|RTLD_LAZY|RTLD_GLOBAL);
        if (!handle) {
            fprintf(stderr, "Error loading module %s: %s\n", path, dlerror());
            goto MODULE_SPEC_LOAD_ERROR;
        }

        mod_spec[i].on_init_cb = (module_on_init_func *) dlsym(handle, init_func_name);
        if (!mod_spec[i].on_init_cb) {
            fprintf(stderr, "Could not load init function %s: %s\n", init_func_name, dlerror());
        }

        mod_spec[i].on_exit_cb = (module_on_exit_func *) dlsym(handle, exit_func_name);
        if (!mod_spec[i].on_exit_cb) {
            fprintf(stderr, "Could not load exit function %s: %s\n", exit_func_name, dlerror());
        }
        FREE(path);
        FREE(init_func_name);
        FREE(exit_func_name);
    }
    return mod_spec;	
MODULE_SPEC_LOAD_ERROR:
	if(mod_spec)FREE(mod_spec);
	*mod_num=0;
	return NULL;	
}

struct stellar_module_manager *stellar_module_manager_new_with_toml(toml_table_t *conf, int max_thread_num, struct mq_schema *mq_schema)
{
	int spec_num = 0;
	struct module_specific *specs = module_specs_load(conf, &spec_num);
	struct stellar_module_manager *mod_mgr = CALLOC(struct stellar_module_manager, 1);
	if(spec_num > 0)
	{
		utarray_new(mod_mgr->schema.module_specs_array,&module_specs_icd);
		utarray_reserve(mod_mgr->schema.module_specs_array, spec_num);
	}
	mod_mgr->schema.max_thread_num=max_thread_num;
	mod_mgr->schema.mq_schema=mq_schema;

	// TODO: store module specific in hash
	for(int i = 0; i < spec_num; i++)
	{
		if (specs[i].on_init_cb != NULL)
		{
			specs[i].mod=specs[i].on_init_cb(mod_mgr);
			if(stellar_module_manager_get_module(mod_mgr, specs[i].mod->name)==NULL)
			{
				utarray_push_back(mod_mgr->schema.module_specs_array, &specs[i]);
			}
			else 
			{
				fprintf(stderr, "Module %s already exists\n", specs[i].mod->name);
				if(specs[i].on_exit_cb)specs[i].on_exit_cb(mod_mgr, specs[i].mod);
			}
		}
	}
	FREE(specs);
	if(mod_mgr->schema.module_specs_array)assert(spec_num==(int)utarray_len(mod_mgr->schema.module_specs_array));
	return mod_mgr;
}

/*******************************************
 * stellar module manager API *
 *******************************************/

struct stellar_module_manager *stellar_module_manager_new(const char *module_spec_toml_path, int max_thread_num, struct mq_schema *mq_schema)
{
	toml_table_t *conf = toml_parse_file_path(module_spec_toml_path);
	struct stellar_module_manager *mod_mgr=stellar_module_manager_new_with_toml(conf, max_thread_num, mq_schema);
	if(conf)toml_free(conf);
	if(module_spec_toml_path)mod_mgr->module_spec_toml_path=strdup(module_spec_toml_path);
	return mod_mgr;
}

void stellar_module_manager_free(struct stellar_module_manager *mod_mgr)
{
	if(mod_mgr==NULL)return;
	struct module_specific *p=NULL;
	if(mod_mgr->module_spec_toml_path)FREE(mod_mgr->module_spec_toml_path);
    if (mod_mgr->schema.module_specs_array)
    {
        while ((p = (struct module_specific *)utarray_next(mod_mgr->schema.module_specs_array, p)))
        {
            if (p->on_exit_cb)
                p->on_exit_cb(mod_mgr, p->mod);
        }
        utarray_free(mod_mgr->schema.module_specs_array);
    }
	FREE(mod_mgr);
	return;
}

int stellar_module_manager_get_max_thread_num(struct stellar_module_manager*mod_mgr)
{
	if(mod_mgr==NULL)return -1;
	return mod_mgr->schema.max_thread_num;
}

struct mq_schema *stellar_module_manager_get_mq_schema(struct stellar_module_manager *mod_mgr)
{
	if(mod_mgr==NULL)return NULL;
	return mod_mgr->schema.mq_schema;
}

const char *stellar_module_manager_get_toml_path(struct stellar_module_manager *mod_mgr)
{
	if(mod_mgr==NULL)return NULL;
	return mod_mgr->module_spec_toml_path;
}

__thread int local_thread_id=-1;
__thread struct mq_runtime *local_mq_rt=NULL;

int stellar_module_manager_get_thread_id(struct stellar_module_manager* mod_mgr __unused)
{
	return local_thread_id;
}

struct mq_runtime *stellar_module_manager_get_mq_runtime(struct stellar_module_manager *mod_mgr __unused)
{
	return local_mq_rt;
}

void stellar_module_manager_register_thread(struct stellar_module_manager* mod_mgr __unused, int thread_id, struct mq_runtime *mq_rt)
{
	local_thread_id=thread_id;
	local_mq_rt=mq_rt;
	return;
}

struct stellar_module *stellar_module_manager_get_module(struct stellar_module_manager *mod_mgr, const char *module_name)
{
	if(mod_mgr==NULL || module_name == NULL)return NULL;
	struct module_specific *p=NULL;
	if (mod_mgr->schema.module_specs_array)
	{
		while ((p = (struct module_specific *)utarray_next(mod_mgr->schema.module_specs_array, p)))
		{
            if (p->mod)
            {
                if (strcmp(p->mod->name, module_name) == 0)
                {
                    return p->mod;
                }
            }
        }
	}
	return NULL;
} 

/*******************************************
 * stellar module API *
 *******************************************/


struct stellar_module *stellar_module_new(const char *name, void *ctx)
{
	struct stellar_module *mod = CALLOC(struct stellar_module, 1);
	memcpy(mod->name, name, MIN(NAME_MAX, strlen(name)));
	mod->module_ctx=ctx;
	return mod;
}

void stellar_module_free(struct stellar_module *mod)
{
	if(mod==NULL)return;
	FREE(mod);
	return;
}

void * stellar_module_get_ctx(struct stellar_module *mod)
{
	if(mod==NULL)return NULL;
	return mod->module_ctx;
}

void stellar_module_set_ctx(struct stellar_module *mod, void *ctx)
{
	if(mod==NULL)return;
	mod->module_ctx=ctx;
	return;
}

const char *stellar_module_get_name(struct stellar_module* mod)
{
	if(mod==NULL)return NULL;
	return mod->name;
}

void stellar_module_set_name(struct stellar_module* mod, const char *name)
{
	if(mod==NULL)return;
	memcpy(mod->name, name, MIN(NAME_MAX, strlen(name)));
	return;
}