#include "module_manager_interna.h"

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


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

#include "toml/toml.h"

int module_specs_load(FILE *fp, struct module_spec_load **mod_spec)
{
	if(fp==NULL|| mod_spec==NULL) return 0;
	int mod_num = 0;
	toml_table_t *conf = toml_parse_file(fp, NULL, 0);
    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_spec_load, mod_num);

	struct stellar_module_manager *mod_mgr = (struct stellar_module_manager *)container_of(mod_spec, struct stellar_module_manager, module_specs);
	
	// TODO: store module specific in hash
    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)
        {
            mod_mgr->module_specs[i].mod = mod_mgr->module_specs[i].on_init_cb(mod_mgr);
            if (stellar_module_manager_get_module(mod_mgr, mod_mgr->module_specs[i].mod->name) == NULL)
            {
                mod_mgr->module_specs[i].is_init_succ = true;
            }
            else
            {
                fprintf(stderr, "Module %s already exists\n", mod_mgr->module_specs[i].mod->name);
                if (mod_mgr->module_specs[i].on_exit_cb)
                    mod_mgr->module_specs[i].on_exit_cb(mod_mgr, mod_mgr->module_specs[i].mod);
                assert(0);
            }
        }
        else
        {
            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());
        }
		mod_spec[i]->path=path;
		mod_spec[i]->init_cb_name=init_func_name;
		mod_spec[i]->exit_cb_name=exit_func_name;
    }
	if(conf	)toml_free(conf);
    return mod_num;	
MODULE_SPEC_LOAD_ERROR:
	if(conf	)toml_free(conf);
	if(*mod_spec)FREE(*mod_spec);
	return 0;	
}

#include <fcntl.h>
#include <unistd.h>
static int stellar_module_manager_get_filepath_from_fp(FILE *fp, char *path, size_t n) 
{
	if(fp==NULL)return -1;
	int fd = fileno(fp); 
    char buf[256];
    snprintf(buf, sizeof(buf), "/proc/self/fd/%d", fd);
    return readlink(buf, path, n - 1);
}


struct stellar_module_manager *stellar_module_manager_new_with_file(FILE *fp, int max_thread_num, struct mq_schema *mq_schema)
{
	
	struct stellar_module_manager *mod_mgr = CALLOC(struct stellar_module_manager, 1);
	mod_mgr->schema.max_thread_num=max_thread_num;
	mod_mgr->schema.mq_schema=mq_schema;
    mod_mgr->load_module_num = module_specs_load(fp, &mod_mgr->module_specs);
    char pathname[FILENAME_MAX] = {};
    if(stellar_module_manager_get_filepath_from_fp(fp, pathname, sizeof(pathname)) > 0)
	{
 	   mod_mgr->module_spec_toml_path = strdup(pathname);
	}
	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)
{
	FILE *fp=fopen(module_spec_toml_path, "r");
	struct stellar_module_manager *mod_mgr=stellar_module_manager_new_with_file(fp, max_thread_num, mq_schema);
	if(fp)fclose(fp);
	return mod_mgr;
}

void stellar_module_manager_free(struct stellar_module_manager *mod_mgr)
{
	if(mod_mgr==NULL)return;
	if(mod_mgr->module_spec_toml_path)FREE(mod_mgr->module_spec_toml_path);
    if (mod_mgr->module_specs)
    {
        for (int i = 0; i < mod_mgr->load_module_num; i++)
        {
            if (mod_mgr->module_specs[i].on_exit_cb != NULL &&
                mod_mgr->module_specs[i].is_init_succ)
            {
                mod_mgr->module_specs[i].on_exit_cb(mod_mgr, mod_mgr->module_specs[i].mod);
            }
			if(mod_mgr->module_specs[i].path)FREE(mod_mgr->module_specs[i].path);
			if(mod_mgr->module_specs[i].init_cb_name)FREE(mod_mgr->module_specs[i].init_cb_name);
			if(mod_mgr->module_specs[i].exit_cb_name)FREE(mod_mgr->module_specs[i].exit_cb_name);
        }
		FREE(mod_mgr->module_specs);
    }
    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;
	if (mod_mgr->module_specs)
	{
		for(int i=0; i<mod_mgr->load_module_num; i++)
		{
			if(mod_mgr->module_specs[i].mod == NULL)break;
			if(strcmp(mod_mgr->module_specs[i].mod->name, module_name)==0 && mod_mgr->module_specs[i].is_init_succ)
			{
				return mod_mgr->module_specs[i].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;
}