/*
 *  BlueZ - Bluetooth protocol stack for Linux
 *
 *  Copyright (C) 2014  Google Inc.
 *
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>
#include <unistd.h>
#include <getopt.h>
#include <limits.h>
#include <errno.h>

#include "lib/bluetooth.h"
#include "lib/hci.h"
#include "lib/hci_lib.h"
#include "lib/l2cap.h"
#include "lib/uuid.h"

#include "src/shared/mainloop.h"
#include "src/shared/util.h"
#include "src/shared/att.h"
#include "src/shared/queue.h"
#include "src/shared/gatt-db.h"
#include "src/shared/gatt-client.h"

#define ATT_CID 4

#define PRLOG(...)       \
	printf(__VA_ARGS__); \
	print_prompt();

#define COLOR_OFF "\x1B[0m"
#define COLOR_RED "\x1B[0;91m"
#define COLOR_GREEN "\x1B[0;92m"
#define COLOR_YELLOW "\x1B[0;93m"
#define COLOR_BLUE "\x1B[0;94m"
#define COLOR_MAGENTA "\x1B[0;95m"
#define COLOR_BOLDGRAY "\x1B[1;30m"
#define COLOR_BOLDWHITE "\x1B[1;37m"

static bool verbose = false;

struct client
{
	int fd;
	struct bt_att *att;
	struct gatt_db *db;
	struct bt_gatt_client *gatt;

	unsigned int reliable_session_id;
};

static void print_prompt(void)
{
	printf(COLOR_BLUE "[GATT client]" COLOR_OFF "# ");
	fflush(stdout);
}

static const char *ecode_to_string(uint8_t ecode)
{
	switch (ecode)
	{
	case BT_ATT_ERROR_INVALID_HANDLE:
		return "Invalid Handle";
	case BT_ATT_ERROR_READ_NOT_PERMITTED:
		return "Read Not Permitted";
	case BT_ATT_ERROR_WRITE_NOT_PERMITTED:
		return "Write Not Permitted";
	case BT_ATT_ERROR_INVALID_PDU:
		return "Invalid PDU";
	case BT_ATT_ERROR_AUTHENTICATION:
		return "Authentication Required";
	case BT_ATT_ERROR_REQUEST_NOT_SUPPORTED:
		return "Request Not Supported";
	case BT_ATT_ERROR_INVALID_OFFSET:
		return "Invalid Offset";
	case BT_ATT_ERROR_AUTHORIZATION:
		return "Authorization Required";
	case BT_ATT_ERROR_PREPARE_QUEUE_FULL:
		return "Prepare Write Queue Full";
	case BT_ATT_ERROR_ATTRIBUTE_NOT_FOUND:
		return "Attribute Not Found";
	case BT_ATT_ERROR_ATTRIBUTE_NOT_LONG:
		return "Attribute Not Long";
	case BT_ATT_ERROR_INSUFFICIENT_ENCRYPTION_KEY_SIZE:
		return "Insuficient Encryption Key Size";
	case BT_ATT_ERROR_INVALID_ATTRIBUTE_VALUE_LEN:
		return "Invalid Attribute value len";
	case BT_ATT_ERROR_UNLIKELY:
		return "Unlikely Error";
	case BT_ATT_ERROR_INSUFFICIENT_ENCRYPTION:
		return "Insufficient Encryption";
	case BT_ATT_ERROR_UNSUPPORTED_GROUP_TYPE:
		return "Group type Not Supported";
	case BT_ATT_ERROR_INSUFFICIENT_RESOURCES:
		return "Insufficient Resources";
	case BT_ERROR_CCC_IMPROPERLY_CONFIGURED:
		return "CCC Improperly Configured";
	case BT_ERROR_ALREADY_IN_PROGRESS:
		return "Procedure Already in Progress";
	case BT_ERROR_OUT_OF_RANGE:
		return "Out of Range";
	default:
		return "Unknown error type";
	}
}

static void att_disconnect_cb(int err, void *user_data)
{
	printf("Device disconnected: %s\n", strerror(err));

	mainloop_quit();
}

static void att_debug_cb(const char *str, void *user_data)
{
	const char *prefix = user_data;

	PRLOG(COLOR_BOLDGRAY "%s" COLOR_BOLDWHITE "%s\n" COLOR_OFF, prefix, str);
}

static void gatt_debug_cb(const char *str, void *user_data)
{
	const char *prefix = user_data;

	PRLOG(COLOR_GREEN "%s%s\n" COLOR_OFF, prefix, str);
}

static void ready_cb(bool success, uint8_t att_ecode, void *user_data);
static void service_changed_cb(uint16_t start_handle, uint16_t end_handle,
							   void *user_data);

static void log_service_event(struct gatt_db_attribute *attr, const char *str)
{
	char uuid_str[MAX_LEN_UUID_STR];
	bt_uuid_t uuid;
	uint16_t start, end;

	gatt_db_attribute_get_service_uuid(attr, &uuid);
	bt_uuid_to_string(&uuid, uuid_str, sizeof(uuid_str));

	gatt_db_attribute_get_service_handles(attr, &start, &end);

	PRLOG("%s - UUID: %s start: 0x%04x end: 0x%04x\n", str, uuid_str,
		  start, end);
}

static void service_added_cb(struct gatt_db_attribute *attr, void *user_data)
{
	log_service_event(attr, "Service Added");
}

static void service_removed_cb(struct gatt_db_attribute *attr, void *user_data)
{
	log_service_event(attr, "Service Removed");
}

static struct client *client_create(int fd, uint16_t mtu)
{
	struct client *cli;

	cli = new0(struct client, 1);
	if (!cli)
	{
		fprintf(stderr, "Failed to allocate memory for client\n");
		return NULL;
	}

	cli->att = bt_att_new(fd, false);
	if (!cli->att)
	{
		fprintf(stderr, "Failed to initialze ATT transport layer\n");
		bt_att_unref(cli->att);
		free(cli);
		return NULL;
	}

	if (!bt_att_set_close_on_unref(cli->att, true))
	{
		fprintf(stderr, "Failed to set up ATT transport layer\n");
		bt_att_unref(cli->att);
		free(cli);
		return NULL;
	}

	if (!bt_att_register_disconnect(cli->att, att_disconnect_cb, NULL,
									NULL))
	{
		fprintf(stderr, "Failed to set ATT disconnect handler\n");
		bt_att_unref(cli->att);
		free(cli);
		return NULL;
	}

	cli->fd = fd;
	cli->db = gatt_db_new();
	if (!cli->db)
	{
		fprintf(stderr, "Failed to create GATT database\n");
		bt_att_unref(cli->att);
		free(cli);
		return NULL;
	}

	cli->gatt = bt_gatt_client_new(cli->db, cli->att, mtu);
	if (!cli->gatt)
	{
		fprintf(stderr, "Failed to create GATT client\n");
		gatt_db_unref(cli->db);
		bt_att_unref(cli->att);
		free(cli);
		return NULL;
	}

	gatt_db_register(cli->db, service_added_cb, service_removed_cb,
					 NULL, NULL);

	if (verbose)
	{
		bt_att_set_debug(cli->att, att_debug_cb, "att: ", NULL);
		bt_gatt_client_set_debug(cli->gatt, gatt_debug_cb, "gatt: ",
								 NULL);
	}

	bt_gatt_client_ready_register(cli->gatt, ready_cb, cli, NULL);
	bt_gatt_client_set_service_changed(cli->gatt, service_changed_cb, cli,
									   NULL);

	/* bt_gatt_client already holds a reference */
	gatt_db_unref(cli->db);

	return cli;
}

static void client_destroy(struct client *cli)
{
	bt_gatt_client_unref(cli->gatt);
	bt_att_unref(cli->att);
	free(cli);
}

static void print_uuid(const bt_uuid_t *uuid)
{
	char uuid_str[MAX_LEN_UUID_STR];
	bt_uuid_t uuid128;

	bt_uuid_to_uuid128(uuid, &uuid128);
	bt_uuid_to_string(&uuid128, uuid_str, sizeof(uuid_str));

	printf("%s\n", uuid_str);
}

static void print_incl(struct gatt_db_attribute *attr, void *user_data)
{
	struct client *cli = user_data;
	uint16_t handle, start, end;
	struct gatt_db_attribute *service;
	bt_uuid_t uuid;

	if (!gatt_db_attribute_get_incl_data(attr, &handle, &start, &end))
		return;

	service = gatt_db_get_attribute(cli->db, start);
	if (!service)
		return;

	gatt_db_attribute_get_service_uuid(service, &uuid);

	printf("\t  " COLOR_GREEN "include" COLOR_OFF " - handle: "
		   "0x%04x, - start: 0x%04x, end: 0x%04x,"
		   "uuid: ",
		   handle, start, end);
	print_uuid(&uuid);
}

static void print_desc(struct gatt_db_attribute *attr, void *user_data)
{
	printf("\t\t  " COLOR_MAGENTA "descr" COLOR_OFF
		   " - handle: 0x%04x, uuid: ",
		   gatt_db_attribute_get_handle(attr));
	print_uuid(gatt_db_attribute_get_type(attr));
}

static void print_chrc(struct gatt_db_attribute *attr, void *user_data)
{
	uint16_t handle, value_handle;
	uint8_t properties;
	uint16_t ext_prop;
	bt_uuid_t uuid;

	if (!gatt_db_attribute_get_char_data(attr, &handle,
										 &value_handle,
										 &properties,
										 &ext_prop,
										 &uuid))
		return;

	printf("\t  " COLOR_YELLOW "charac" COLOR_OFF
		   " - start: 0x%04x, value: 0x%04x, "
		   "props: 0x%02x, ext_props: 0x%04x, uuid: ",
		   handle, value_handle, properties, ext_prop);
	print_uuid(&uuid);

	gatt_db_service_foreach_desc(attr, print_desc, NULL);
}

static void print_service(struct gatt_db_attribute *attr, void *user_data)
{
	struct client *cli = user_data;
	uint16_t start, end;
	bool primary;
	bt_uuid_t uuid;

	if (!gatt_db_attribute_get_service_data(attr, &start, &end, &primary,
											&uuid))
		return;

	printf(COLOR_RED "service" COLOR_OFF " - start: 0x%04x, "
					 "end: 0x%04x, type: %s, uuid: ",
		   start, end, primary ? "primary" : "secondary");
	print_uuid(&uuid);

	gatt_db_service_foreach_incl(attr, print_incl, cli);
	gatt_db_service_foreach_char(attr, print_chrc, NULL);

	printf("\n");
}

static void print_services(struct client *cli)
{
	printf("\n");

	gatt_db_foreach_service(cli->db, NULL, print_service, cli);
}

static void print_services_by_uuid(struct client *cli, const bt_uuid_t *uuid)
{
	printf("\n");

	gatt_db_foreach_service(cli->db, uuid, print_service, cli);
}

static void print_services_by_handle(struct client *cli, uint16_t handle)
{
	printf("\n");

	/* TODO: Filter by handle */
	gatt_db_foreach_service(cli->db, NULL, print_service, cli);
}

static void ready_cb(bool success, uint8_t att_ecode, void *user_data)
{
	struct client *cli = user_data;

	if (!success)
	{
		PRLOG("GATT discovery procedures failed - error code: 0x%02x\n",
			  att_ecode);
		return;
	}

	PRLOG("GATT discovery procedures complete\n");

	print_services(cli);
	print_prompt();
}

static void service_changed_cb(uint16_t start_handle, uint16_t end_handle,
							   void *user_data)
{
	struct client *cli = user_data;

	printf("\nService Changed handled - start: 0x%04x end: 0x%04x\n",
		   start_handle, end_handle);

	gatt_db_foreach_service_in_range(cli->db, NULL, print_service, cli,
									 start_handle, end_handle);
	print_prompt();
}




static int __l2cap_le_att_connect(bdaddr_t *src, bdaddr_t *dst, uint8_t dst_type,
								  int sec)
{
	int sock;
	struct sockaddr_l2 srcaddr, dstaddr;
	struct bt_security btsec;

	if (verbose)
	{
		char srcaddr_str[18], dstaddr_str[18];

		ba2str(src, srcaddr_str);
		ba2str(dst, dstaddr_str);

		printf("btgatt-client: Opening L2CAP LE connection on ATT "
			   "channel:\n\t src: %s\n\tdest: %s\n",
			   srcaddr_str, dstaddr_str);
	}

	sock = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP);
	if (sock < 0)
	{
		perror("Failed to create L2CAP socket");
		return -1;
	}

	/* Set up source address */
	memset(&srcaddr, 0, sizeof(srcaddr));
	srcaddr.l2_family = AF_BLUETOOTH;
	srcaddr.l2_cid = htobs(ATT_CID);
	srcaddr.l2_bdaddr_type = 0;
	bacpy(&srcaddr.l2_bdaddr, src);

	if (bind(sock, (struct sockaddr *)&srcaddr, sizeof(srcaddr)) < 0)
	{
		perror("Failed to bind L2CAP socket");
		close(sock);
		return -1;
	}

	/* Set the security level */
	memset(&btsec, 0, sizeof(btsec));
	btsec.level = sec;
	if (setsockopt(sock, SOL_BLUETOOTH, BT_SECURITY, &btsec,
				   sizeof(btsec)) != 0)
	{
		fprintf(stderr, "Failed to set L2CAP security level\n");
		close(sock);
		return -1;
	}

	/* Set up destination address */
	memset(&dstaddr, 0, sizeof(dstaddr));
	dstaddr.l2_family = AF_BLUETOOTH;
	dstaddr.l2_cid = htobs(ATT_CID);
	dstaddr.l2_bdaddr_type = dst_type;
	bacpy(&dstaddr.l2_bdaddr, dst);

	printf("Connecting to device...");
	fflush(stdout);

	if (connect(sock, (struct sockaddr *)&dstaddr, sizeof(dstaddr)) < 0)
	{
		perror(" Failed to connect");
		close(sock);
		return -1;
	}

	printf(" Done\n");

	return sock;
}

int l2cap_le_att_connect(int dev_id, char *dst, uint8_t dst_type,
								int sec, uint16_t mtu)
{
	int opt;
	bdaddr_t src_addr, dst_addr;
	int fd;
	sigset_t mask;
	struct client *cli;

	if (str2ba(dst, &dst_addr) < 0)
	{
		fprintf(stderr, "Invalid remote address: %s\n",
				optarg);
		return EXIT_FAILURE;
	}

	if (dev_id == -1)
		bacpy(&src_addr, BDADDR_ANY);
	else if (hci_devba(dev_id, &src_addr) < 0)
	{
		perror("Adapter not available");
		return EXIT_FAILURE;
	}

	fd = __l2cap_le_att_connect(&src_addr, &dst_addr, dst_type, sec);
	if (fd < 0)
		return EXIT_FAILURE;

	cli = client_create(fd, mtu);
	if (!cli)
	{
		close(fd);
		return EXIT_FAILURE;
	}
}