#include <lua.h>

#include <lauxlib.h>

#include <glib.h>

#include <loudmouth/loudmouth.h>

#include <stdio.h>

#include "util.h"

#include "lm_types.h"

/// lm.ssl

/// Object, containing information about ssl abilities for connection.

/// Create, set parameters, and attach to connection with 'ssl' method.

/// ssl status

/// String, representing what problem have current ssl session.

/// V: no cert found, untrusted cert, cert expired, cert not activated, cert hostname mismatch, cert fingerprint mismatch, generic error

const string2enum_t llm_ssl_status[] = {

	{ "no cert found",             LM_SSL_STATUS_NO_CERT_FOUND             },

	{ "untrusted cert",            LM_SSL_STATUS_UNTRUSTED_CERT            },

	{ "cert expired",              LM_SSL_STATUS_CERT_EXPIRED              },

	{ "cert not activated",        LM_SSL_STATUS_CERT_NOT_ACTIVATED        },

	{ "cert hostname mismatch",    LM_SSL_STATUS_CERT_HOSTNAME_MISMATCH    },

	{ "cert fingerprint mismatch", LM_SSL_STATUS_CERT_FINGERPRINT_MISMATCH },

	{ "generic error",             LM_SSL_STATUS_GENERIC_ERROR             },

	{ NULL,                        0                                       }, // XXX

};

/// ssl callback function

/// User function, called when ssl error happens.

/// XXX: add lm connection object to args? it is not in API, but can be useful,

/// though, with upvalues it is not required.

/// A: lm ssl object, ssl status

/// R: boolean (false if connection process should be terminated)

LmSSLResponse llm_ssl_callback (LmSSL *ssl, LmSSLStatus status, llm_callback_t *cb)

{

	int ret;

	lua_rawgeti (cb->L, LUA_REGISTRYINDEX, cb->reference);

	llm_ssl_bless (cb->L, ssl);

	// XXX lm_ssl_unref (ssl);

	luaL_pushenum (cb->L, status, llm_ssl_status);

	if (lua_pcall (cb->L, 2, 0, 0)) {

		// XXX lua_error (cb->L);

		lua_pop (cb->L, 1);

		return LM_SSL_RESPONSE_CONTINUE;

	}

	ret = lua_toboolean (cb->L, -1);

	lua_pop (cb->L, 1);

	if (ret)

		return LM_SSL_RESPONSE_CONTINUE;

	else

		return LM_SSL_RESPONSE_STOP;

}

static void string2fingerprint (const char *string, char *buffer)

{

	int i;

	for (i = 0; i < 16; i++) {

		int h = g_ascii_xdigit_value ((char)string[i*3]);

		int l = g_ascii_xdigit_value ((char)string[i*3+1]);

		buffer[i] = (char) ((h >= 0 && l >= 0) ? h*16 + l : 0);

	}

}

/// lm.ssl.new

/// Creates new ssl object for use with connection.

/// You can specify server key fingerprint, callback function for error handling,

/// both, or neither. Though, fingerprint should go before callback function.

/// SSL fingerprint is a string like '01:23:45:67:89:AB:CD:EF:FE:DC:BA:98:76:54:32:10'.

/// A: string (optional ssl fingerprint), ssl callback function (optional)

/// R: lm ssl object

static int llm_ssl_new (lua_State *L)

{

	int args = lua_gettop (L);

	LmSSL *ssl;

	if (args == 0)

		ssl = lm_ssl_new (NULL, NULL, NULL, NULL);

	else if (args == 1 && !lua_isfunction (L, 1)) {

		gchar buffer[16] = "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0";

		const char *fingerprint = luaL_checkstring (L, 1);

		if (lua_objlen (L, 1) > 46)

			string2fingerprint (fingerprint, buffer);

		ssl = lm_ssl_new (buffer, NULL, NULL, NULL);

		lua_pop (L, 1);

	} else {

		llm_callback_t *cb;

		gchar buffer[16] = "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0";

		if (args > 1) {

			const char *fingerprint = luaL_checkstring (L, 1);

			if (lua_objlen (L, 1) > 46)

				string2fingerprint (fingerprint, buffer);

			luaL_argcheck (L, lua_isfunction (L, 2), 2, "function expected");

		} else

			luaL_argcheck (L, lua_isfunction (L, 1), 1, "function expected");

		cb = luaL_malloc (L, sizeof (llm_callback_t));

		cb->reference = luaL_ref (L, LUA_REGISTRYINDEX);

		cb->L = L;

		ssl = lm_ssl_new ((args > 1) ? buffer : NULL, (LmSSLFunction)llm_ssl_callback,

							cb, (GDestroyNotify)llm_callback_destroy);

		lua_pop (L, 1);

	}

	llm_ssl_bless (L, ssl);

	lm_ssl_unref (ssl); // XXX

	return 1;

}

/// lm.ssl.bless

/// Blesses given pointer to lm ssl object.

/// A: lightuserdata (C lm ssl object)

/// R: lm ssl object

static int llm_ssl_bless_lua (lua_State *L)

{

	luaL_argcheck (L, lua_islightuserdata (L, 1), 1, "lm ssl lightuserdata expected");

	llm_ssl_bless (L, lua_touserdata (L, 1));

	lua_remove (L, -2);

	return 1;

}

/// lm.ssl.supported

/// Indicates if SSL is supported by loudmouth library.

/// R: boolean

static int llm_ssl_supported (lua_State *L)

{

	lua_pushboolean (L, lm_ssl_is_supported ());

	return 1;

}

/// ssl:fingerprint

/// Returns fingerprint of remote server.

/// R: string or nil

static int llm_ssl_fingerprint (lua_State *L)

{

	char buffer[48];

	llm_ssl_t *object = luaL_checklm_ssl (L, 1);

	const gchar *fingerprint = lm_ssl_get_fingerprint (object->ssl);

	if (fingerprint == NULL)

		lua_pushnil (L);

	else {

		snprintf (buffer, 48,

			  "%02hhX:%02hhX:%02hhX:%02hhX:%02hhX:%02hhX:%02hhX:%02hhX:"

			  "%02hhX:%02hhX:%02hhX:%02hhX:%02hhX:%02hhX:%02hhX:%02hhX",

			  fingerprint[0], fingerprint[1], fingerprint[2], fingerprint[3],

			  fingerprint[4], fingerprint[5], fingerprint[6], fingerprint[7],

			  fingerprint[8], fingerprint[9], fingerprint[10], fingerprint[11],

			  fingerprint[12], fingerprint[13], fingerprint[14], fingerprint[15]);

		lua_pushlstring (L, buffer, 47);

	}

	lua_remove (L, -2);

	return 1;

}

/// ssl:pointer

/// Returns pointer to underlying C structure.

/// R: lightuserdata

static int llm_ssl_pointer (lua_State *L)

{

	llm_ssl_t *object = luaL_checklm_ssl (L, 1);

	lua_pushlightuserdata (L, object->ssl);

	lua_remove (L, -2);

	return 1;

}

static int llm_ssl_gc (lua_State *L)

{

	llm_ssl_t *object = luaL_checklm_ssl (L, 1);

	lm_ssl_unref (object->ssl);

	lua_pop (L, 1);

	return 0;

}

const static luaL_Reg llm_ssl_reg_f[] = {

	{ "new",       llm_ssl_new       },

	{ "bless",     llm_ssl_bless_lua },

	{ "supported", llm_ssl_supported },

	{ NULL,        NULL              },

};

const static luaL_Reg llm_ssl_reg_m[] = {

	{ "fingerprint", llm_ssl_fingerprint },

	{ "pointer",     llm_ssl_pointer     },

	{ "__gc",        llm_ssl_gc          },

	{ NULL,          NULL                },

};

int luaopen_lm_ssl (lua_State *L)

{

	luaL_newmetatable (L, "loudmouth.ssl");

	lua_pushstring (L, "__index");

	lua_pushvalue (L, -2);

	lua_settable (L, -3);

	luaL_register (L, NULL, llm_ssl_reg_m);

	lua_pop (L, 1);

	luaL_register (L, "lm.ssl", llm_ssl_reg_f);

	return 1;

}