#include "../../uwsgi.h"

#include <lua.h>
#include <lualib.h>
#include <lauxlib.h>

extern struct uwsgi_server uwsgi;

struct uwsgi_lua {
	struct lua_State **L;

	char *filename;
	struct uwsgi_string_list *load;
} ulua;

#define lca(L, n)		ulua_check_args(L, __FUNCTION__, n)

static struct uwsgi_option uwsgi_lua_options[] = {

	{"lua", required_argument, 0, "load lua wsapi app", uwsgi_opt_set_str, &ulua.filename, 0},
	{"lua-load", required_argument, 0, "load a lua file", uwsgi_opt_add_string_list, &ulua.load, 0},

	{0, 0, 0, 0},

};

static void ulua_check_args(lua_State *L, const char *func, int n) {
	int args = lua_gettop(L);
	char error[1024];
	if (args != n) {
		if (n == 1) {
			snprintf(error, 1024, "uwsgi.%s takes 1 parameter", func+10);
		}
		else {
			snprintf(error, 1024, "uwsgi.%s takes %d parameters", func+10, n);
		}
		lua_pushstring(L, error);
        	lua_error(L);
	}
}

static int uwsgi_api_log(lua_State *L) {
	
	const char *logline ;

	lca(L, 1);

	if (lua_isstring(L, 1)) {
		logline = lua_tolstring(L, 1, NULL);
                uwsgi_log( "%s\n", logline);
	}

	return 0;
}

static int uwsgi_api_register_rpc(lua_State *L) {

        uint8_t argc = lua_gettop(L);
	const char *name;
	// a hack for 64bit;
	int func;
	long lfunc;

	if (argc < 2) {
		lua_pushnil(L);
		return 1;
	}

	name = lua_tolstring(L, 1, NULL);

	lua_pushvalue(L, 2);
        func = luaL_ref(L, LUA_REGISTRYINDEX);

	uwsgi_log("registered function %d in Lua global table\n", func);
	lfunc = func;

        if (uwsgi_register_rpc((char *)name, 6, 0, (void *) lfunc)) {
		lua_pushnil(L);
        }
	else {
		lua_pushboolean(L, 1);
	}

	return 1;
}

static int uwsgi_api_cache_set(lua_State *L) {

	uint8_t argc = lua_gettop(L);
        const char *key ;
        const char *value ;
        uint64_t expires = 0;
	size_t vallen;
	size_t keylen;
	const char *cache = NULL;

	if (argc < 2) goto error;

	key = lua_tolstring(L, 1, &keylen);
	value = lua_tolstring(L, 2, &vallen);
	if (argc > 2) {
		expires = lua_tonumber(L, 3);
		if (argc > 3) {
			cache = lua_tolstring(L, 4, NULL);
		}
	}

        if (!uwsgi_cache_magic_set((char *)key, keylen, (char *)value, vallen, expires, 0, (char *) cache)) {
		lua_pushboolean(L, 1);
		return 1;
	}
error:

	lua_pushnil(L);
	return 1;

}

static int uwsgi_api_cache_update(lua_State *L) {

        uint8_t argc = lua_gettop(L);
        const char *key ;
        const char *value ;
        uint64_t expires = 0;
        size_t vallen;
        size_t keylen;
        const char *cache = NULL;

        if (argc < 2) goto error;

        key = lua_tolstring(L, 1, &keylen);
        value = lua_tolstring(L, 2, &vallen);
        if (argc > 2) {
                expires = lua_tonumber(L, 3);
                if (argc > 3) {
                        cache = lua_tolstring(L, 4, NULL);
                }
        }       

        if (!uwsgi_cache_magic_set((char *)key, keylen, (char *)value, vallen, expires, UWSGI_CACHE_FLAG_UPDATE, (char *)cache)) {
                lua_pushboolean(L, 1);
                return 1;
        }
error:

        lua_pushnil(L);
        return 1;

}


static int uwsgi_api_register_signal(lua_State *L) {

	int args = lua_gettop(L);
	uint8_t sig;
	long lhandler;
	const char *who;
	
	if (args >= 3) {

		sig = lua_tonumber(L, 1);
		who = lua_tostring(L, 2);
		lua_pushvalue(L, 3);
		lhandler = luaL_ref(L, LUA_REGISTRYINDEX);

		uwsgi_register_signal(sig, (char *)who, (void *) lhandler, 6);
	}

	lua_pushnil(L);
        return 1;
}

static int uwsgi_api_cache_clear(lua_State *L) {

        const char *cache = NULL;
        uint8_t argc = lua_gettop(L);

        if (argc > 0) {
        	cache = lua_tolstring(L, 2, NULL);
        }
        if (!uwsgi_cache_magic_clear((char *)cache)) {
        	lua_pushboolean(L, 1);
                return 1;
        }

        lua_pushnil(L);
        return 1;

}


static int uwsgi_api_cache_del(lua_State *L) {

        size_t keylen;
        const char *key ;
        const char *cache = NULL;
        uint8_t argc = lua_gettop(L);

        if (argc == 0) goto error;

        if (lua_isstring(L, 1)) {
                // get the key
                key = lua_tolstring(L, 1, &keylen);
                if (argc > 1) {
                        cache = lua_tolstring(L, 2, NULL);
                }
                if (!uwsgi_cache_magic_del((char *)key, keylen, (char *)cache)) {
                        lua_pushboolean(L, 1);
                        return 1;
                }
        }

error:
        lua_pushnil(L);
        return 1;

}


static int uwsgi_api_cache_exists(lua_State *L) {

        size_t keylen;
        const char *key ;
        const char *cache = NULL;
        uint8_t argc = lua_gettop(L);

        if (argc == 0) goto error;

        if (lua_isstring(L, 1)) {
                // get the key
                key = lua_tolstring(L, 1, &keylen);
                if (argc > 1) {
                        cache = lua_tolstring(L, 2, NULL);
                }
                if (uwsgi_cache_magic_exists((char *)key, keylen,(char *)cache)) {
			lua_pushboolean(L, 1);
                	return 1;
                }
        }

error:
        lua_pushnil(L);
        return 1;

}


static int uwsgi_api_cache_get(lua_State *L) {

        char *value ;
        uint64_t valsize;
	size_t keylen;
	const char *key ;
	const char *cache = NULL;
	uint8_t argc = lua_gettop(L);

	if (argc == 0) goto error;

	if (lua_isstring(L, 1)) {
		// get the key
		key = lua_tolstring(L, 1, &keylen);
		if (argc > 1) {
			cache = lua_tolstring(L, 2, NULL);
		}
        	value = uwsgi_cache_magic_get((char *)key, keylen, &valsize, (char *)cache);
        	if (value) {
                	lua_pushlstring(L, value, valsize);
			free(value);
			return 1;
        	}
	}

error:
	lua_pushnil(L);
        return 1;

}

static int uwsgi_api_req_fd(lua_State *L) {

	struct wsgi_request *wsgi_req = current_wsgi_req();
	
	lua_pushnumber(L, wsgi_req->fd);
	return 1;
}

static int uwsgi_api_lock(lua_State *L) {

	int lock_num = 0;

	// the spooler cannot lock resources
	if (uwsgi.i_am_a_spooler) {
		lua_pushstring(L, "The spooler cannot lock/unlock resources");
		lua_error(L);
	}

	if (lua_gettop(L) > 0) {
		lock_num = lua_isnumber(L, 1) ? lua_tonumber(L, 1) : -1;
		if (lock_num < 0 || lock_num > uwsgi.locks) {
			lua_pushstring(L, "Invalid lock number");
	    		lua_error(L);
	  	}
	}
	
	uwsgi_lock(uwsgi.user_lock[lock_num]);

	return 0;
}


static int uwsgi_api_unlock(lua_State *L) {

	int lock_num = 0;

	// the spooler cannot lock resources
	if (uwsgi.i_am_a_spooler) {
		lua_pushstring(L, "The spooler cannot lock/unlock resources");
		lua_error(L);
	}

	if (lua_gettop(L) > 0) {
		lock_num = lua_isnumber(L, 1) ? lua_tonumber(L, 1) : -1;
		if (lock_num < 0 || lock_num > uwsgi.locks) {
			lua_pushstring(L, "Invalid lock number");
	    		lua_error(L);
	  	}
	}
	
	uwsgi_unlock(uwsgi.user_lock[lock_num]);

	return 0;
}

static const luaL_reg uwsgi_api[] = {
  {"log", uwsgi_api_log},
  {"connection_fd", uwsgi_api_req_fd},

  {"cache_get", uwsgi_api_cache_get},
  {"cache_set", uwsgi_api_cache_set},
  {"cache_update", uwsgi_api_cache_update},
  {"cache_del", uwsgi_api_cache_del},
  {"cache_exists", uwsgi_api_cache_exists},
  {"cache_clear", uwsgi_api_cache_clear},

  {"register_signal", uwsgi_api_register_signal},
  {"register_rpc", uwsgi_api_register_rpc},

  {"lock", uwsgi_api_lock},
  {"unlock", uwsgi_api_unlock},
  {NULL, NULL}
};



static int uwsgi_lua_input(lua_State *L) {

	struct wsgi_request *wsgi_req = current_wsgi_req();
	ssize_t sum = 0;

	int n = lua_gettop(L);

	if (n > 1) {
		sum = lua_tonumber(L, 2);
	}

	ssize_t rlen = 0;

        char *buf = uwsgi_request_body_read(wsgi_req, sum, &rlen);
        if (buf) {
		lua_pushlstring(L, buf, rlen);
                return 1;
        }

	return 0;
}

static int uwsgi_lua_init(){

	uwsgi_log("Initializing Lua environment... (%d lua_States)\n", uwsgi.cores);

	ulua.L = uwsgi_malloc( sizeof(lua_State*) * uwsgi.cores );

	// ok the lua engine is ready
	return 0;


}

static void uwsgi_lua_app() {
	int i;

	if (!ulua.filename && !ulua.load) return;

		for(i=0;i<uwsgi.cores;i++) {
			ulua.L[i] = luaL_newstate();
			luaL_openlibs(ulua.L[i]);
			luaL_register(ulua.L[i], "uwsgi", uwsgi_api);

			struct uwsgi_string_list *usl = ulua.load;
			while(usl) {
				if (luaL_dofile(ulua.L[i], usl->value)) {
                                        uwsgi_log("unable to load Lua file %s: %s\n", usl->value, lua_tostring(ulua.L[i], -1));
                                        exit(1);
                                }
				usl = usl->next;
			}

			if (ulua.filename) {
				if (luaL_loadfile(ulua.L[i], ulua.filename)) {
					uwsgi_log("unable to load Lua file %s: %s\n", ulua.filename, lua_tostring(ulua.L[i], -1));
					exit(1);
				}
			
				// use a pcall
				//lua_call(ulua.L[i], 0, 1);
				if (lua_pcall(ulua.L[i], 0, 1, 0) != 0) {
					uwsgi_log("%s\n", lua_tostring(ulua.L[i], -1));
					exit(1);
				}
			
				// if the loaded lua app returns as a table, fetch the
				// run function.
				if (lua_istable(ulua.L[i], 2)) {
					lua_pushstring(ulua.L[i], "run" );
					lua_gettable(ulua.L[i], 2);
					lua_replace(ulua.L[i], 2);
				}
					
				if (! lua_isfunction(ulua.L[i], 2))	{
					uwsgi_log("Can't find WSAPI entry point (no function, nor a table with function'run').\n");
					exit(1);
				}
			}

	}
}

static int uwsgi_lua_request(struct wsgi_request *wsgi_req) {

	int i;
	const char *http, *http2;
	size_t slen, slen2;
	char *ptrbuf;
	lua_State *L = ulua.L[wsgi_req->async_id];

	if (wsgi_req->async_status == UWSGI_AGAIN) {
		if ((i = lua_pcall(L, 0, 1, 0)) == 0) {
			if (lua_type(L, -1) == LUA_TSTRING) {
				http = lua_tolstring(L, -1, &slen);
				uwsgi_response_write_body_do(wsgi_req, (char *)http, slen);
			}
			lua_pop(L, 1);
			lua_pushvalue(L, -1);
			return UWSGI_AGAIN;
		}
		goto clear;
	}

	/* Standard WSAPI request */
	if (!wsgi_req->uh->pktsize) {
		uwsgi_log( "Empty lua request. skip.\n");
		return -1;
	}

	if (uwsgi_parse_vars(wsgi_req)) {
		return -1;
	}

	// put function in the stack
	//lua_getfield(L, LUA_GLOBALSINDEX, "run");
	lua_pushvalue(L, -1);

	// put cgi vars in the stack

	lua_newtable(L);
	lua_pushstring(L, "");
	lua_setfield(L, -2, "CONTENT_TYPE");
	for(i=0;i<wsgi_req->var_cnt;i++) {
		lua_pushlstring(L, (char *)wsgi_req->hvec[i+1].iov_base, wsgi_req->hvec[i+1].iov_len);
		// transform it in a valid c string TODO this is ugly
		ptrbuf = wsgi_req->hvec[i].iov_base+wsgi_req->hvec[i].iov_len;
		*ptrbuf = 0;
		lua_setfield(L, -2, (char *)wsgi_req->hvec[i].iov_base);
		i++;
	}


	// put "input" table
	lua_newtable(L);
	lua_pushcfunction(L, uwsgi_lua_input);
	lua_setfield(L, -2, "read");
	lua_setfield(L, -2, "input");

#ifdef UWSGI_DEBUG
	uwsgi_log("stack pos %d\n", lua_gettop(L));
#endif

	// call function
	i = lua_pcall(L, 1, 3, 0);
	if (i != 0) {
		uwsgi_log("%s\n", lua_tostring(L, -1));
		lua_pop(L, 1);
                lua_pushvalue(L, -1);
		goto clear;
	}

	//uwsgi_log("%d %s %s %s\n",i,lua_typename(L, lua_type(L, -3)), lua_typename(L, lua_type(L, -2)) ,  lua_typename(L, lua_type(L, -1)));

	// send status
	if (lua_type(L, -3) == LUA_TSTRING || lua_type(L, -3) == LUA_TNUMBER) {
		http = lua_tolstring(L, -3, &slen);
		uwsgi_response_prepare_headers(wsgi_req, (char *) http, slen);
	}
	else {
		uwsgi_log("[uwsgi-lua] invalid response status !!!\n");
		// let's continue 
	}

	// send headers

	lua_pushnil(L);
	while(lua_next(L, -3) != 0) {
		http = lua_tolstring(L, -2, &slen);
		http2 = lua_tolstring(L, -1, &slen2);
		uwsgi_response_add_header(wsgi_req, (char *) http, slen, (char *) http2, slen2);
		lua_pop(L, 1);
	}

	// send body with coroutine
	lua_pushvalue(L, -1);

	while ( (i = lua_pcall(L, 0, 1, 0)) == 0) {
		if (lua_type(L, -1) == LUA_TSTRING) {
			http = lua_tolstring(L, -1, &slen);
			uwsgi_response_write_body_do(wsgi_req, (char *)http, slen);
		}
		lua_pop(L, 1);
		lua_pushvalue(L, -1);
		if (uwsgi.async > 1) {
			return UWSGI_AGAIN;
		}
	}

clear:
	lua_pop(L, 4);
	// set frequency
	lua_gc(L, LUA_GCCOLLECT, 0);

	return UWSGI_OK;

}

static void uwsgi_lua_after_request(struct wsgi_request *wsgi_req) {

	log_request(wsgi_req);
}


static int uwsgi_lua_magic(char *mountpoint, char *lazy) {

	if (!strcmp(lazy+strlen(lazy)-4, ".lua")) {
                ulua.filename = lazy;
                return 1;
        }
        else if (!strcmp(lazy+strlen(lazy)-3, ".ws")) {
                ulua.filename = lazy;
                return 1;
        }


	return 0;
}

static char *uwsgi_lua_code_string(char *id, char *code, char *func, char *key, uint16_t keylen) {

	static struct lua_State *L = NULL;

	if (!L) {
		L = luaL_newstate();
                luaL_openlibs(L);
                if (luaL_loadfile(L, code) || lua_pcall(L, 0, 0, 0)) {
                	uwsgi_log("unable to load file %s: %s\n", code, lua_tostring(L, -1));
			lua_close(L);
			L = NULL;
			return NULL;
                }
		lua_getglobal(L, func);
		if (!lua_isfunction(L,-1)) {
			uwsgi_log("unable to find %s function in lua file %s\n", func, code);
			lua_close(L);
			L = NULL;
			return NULL;
		}
		lua_pushnil(L);
	}

	
	lua_pop(L, 1);

	lua_pushvalue(L, -1);
	lua_pushlstring(L, key, keylen);

#ifdef UWSGI_DEBUG
	uwsgi_log("stack pos %d %.*s\n", lua_gettop(L), keylen, key);
#endif

        if (lua_pcall(L, 1, 1, 0) != 0) {
                uwsgi_log("error running function `f': %s",
                 lua_tostring(L, -1));
                return NULL;

        }

	if (lua_isstring(L, -1)) {
                const char *ret = lua_tolstring(L, -1, NULL);
		return (char *)ret;
        }

        return NULL;
}

static int uwsgi_lua_signal_handler(uint8_t sig, void *handler) {

	struct wsgi_request *wsgi_req = current_wsgi_req();
	
	lua_State *L = ulua.L[wsgi_req->async_id];

#ifdef UWSGI_DEBUG
	uwsgi_log("managing signal handler on core %d\n", wsgi_req->async_id);
#endif

	lua_rawgeti(L, LUA_REGISTRYINDEX, (long) handler);

	lua_pushnumber(L, sig);

	if (lua_pcall(L, 1, 1, 0) != 0) {
		uwsgi_log("error running function `f': %s",
                 lua_tostring(L, -1));

		return -1;

	}

	return 0;
	
}

static uint16_t uwsgi_lua_rpc(void * func, uint8_t argc, char **argv, uint16_t argvs[], char *buffer) {

        uint8_t i;
        const char *sv;
        size_t sl;
	long lfunc = (long) func;
	int ifunc = lfunc;

	struct wsgi_request *wsgi_req = current_wsgi_req();
	
	lua_State *L = ulua.L[wsgi_req->async_id];

#ifdef UWSGI_DEBUG
	uwsgi_log("get function %d\n", ifunc);
#endif
	lua_rawgeti(L, LUA_REGISTRYINDEX, ifunc);

        for(i=0;i<argc;i++) {
		lua_pushlstring(L, argv[i], argvs[i]);
        }

        if (lua_pcall(L, argc, 1, 0) != 0) {
		uwsgi_log("error running function `f': %s", lua_tostring(L, -1));
		return 0;
        }

	
	sv = lua_tolstring(L, -1, &sl);

#ifdef UWSGI_DEBUG
	uwsgi_log("sv = %s sl = %lu\n", sv, (unsigned long) sl);
#endif
	if (sl <= 0xffff) {
		memcpy(buffer, sv, sl);
		lua_pop(L, 1);
		return sl;
	}

	lua_pop(L, 1);
        return 0;

}

static void uwsgi_lua_configurator_array(lua_State *L) { 

	int i;
	int n = luaL_getn(L, -3);

	for(i=1;i<=n;i++) {
		lua_rawgeti(L, 1, i);
		if (lua_istable(L, -1)) {
                	lua_pushnil(L);
                        while (lua_next(L, -2) != 0) {
                        	char *key = uwsgi_str((char *)lua_tostring(L, -2));
                                char *value = uwsgi_str((char *)lua_tostring(L, -1));
                                add_exported_option(key, value, 0);
                                lua_pop(L, 1);
                        }
                }
	}
}


static void uwsgi_lua_configurator(char *filename, char *magic_table[]) {
	size_t len = 0;
	uwsgi_log_initial("[uWSGI] getting Lua configuration from %s\n", filename);
	char *code = uwsgi_open_and_read(filename, &len, 1, magic_table);
	lua_State *L = luaL_newstate();
	if (!L) {
		uwsgi_log("unable to initialize Lua state for configuration\n");
		exit(1);
	}
        luaL_openlibs(L);
	if (luaL_dostring(L, code) != 0) {
		uwsgi_log("error running Lua configurator: %s\n", lua_tostring(L, -1));
		exit(1);
	}
	free(code);

	if (!lua_istable(L, -1)) {
		uwsgi_log("Lua configurator has to return a table !!!\n");
		exit(1);
	}

	lua_pushnil(L);
	// we always use uwsgi_str to avoid GC destroying our strings
	// and to be able to call lua_close at the end
	while (lua_next(L, -2) != 0) {
		// array ?
		if (lua_isnumber(L, -2)) {
			uwsgi_lua_configurator_array(L);
			break;
		}
		// dictionary
		else {
			char *key = uwsgi_str((char *)lua_tostring(L, -2));
			if (lua_istable(L, -1)) {
				lua_pushnil(L);
				while (lua_next(L, -2) != 0) {
					char *value = uwsgi_str((char *)lua_tostring(L, -1));
					add_exported_option(key, value, 0);
					lua_pop(L, 1);
				}	
			}
			else {
				char *value = uwsgi_str((char *)lua_tostring(L, -1));
				add_exported_option(key, value, 0);
			}
		}
		lua_pop(L, 1);
	}

	// this will destroy the whole Lua state
	lua_close(L);
}

static void uwsgi_register_lua_features() {
	uwsgi_register_configurator(".lua", uwsgi_lua_configurator);
}


struct uwsgi_plugin lua_plugin = {

	.name = "lua",
	.modifier1 = 6,
	.init = uwsgi_lua_init,
	.options = uwsgi_lua_options,
	.request = uwsgi_lua_request,
	.after_request = uwsgi_lua_after_request,
	.init_apps = uwsgi_lua_app,
	.magic = uwsgi_lua_magic,
	.signal_handler = uwsgi_lua_signal_handler,

	.code_string = uwsgi_lua_code_string,
	.rpc = uwsgi_lua_rpc,

	.on_load = uwsgi_register_lua_features,
};