/*
 * This file is part of the libsigrok project.
 *
 * Copyright (C) 2013 Bert Vermeulen <bert@biot.com>
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */

#include <config.h>
#include <string.h>
#include "protocol.h"

static const uint32_t scanopts[] = {
	SR_CONF_CONN,
};

static const uint32_t drvopts[] = {
	SR_CONF_THERMOMETER,
};

static const uint32_t devopts[] = {
	SR_CONF_CONTINUOUS,
	SR_CONF_LIMIT_SAMPLES | SR_CONF_GET | SR_CONF_SET,
	SR_CONF_LIMIT_MSEC | SR_CONF_GET | SR_CONF_SET,
	SR_CONF_DATA_SOURCE | SR_CONF_GET | SR_CONF_SET | SR_CONF_LIST,
};

/*
 * BEWARE! "T1-T2" looks like a range, and is probably not a good
 * channel name. Using it in sigrok-cli -C specs is troublesome. Use
 * "delta" instead? -- But OTOH channels are not selected by the
 * software. Instead received packets just reflect the one channel
 * that manually was selected by the user via the device's buttons.
 * So the name is not a blocker, and it matches the labels on the
 * device and in the manual. So we can get away with it.
 */
static const char *channel_names[] = {
	"T1", "T2", "T1-T2",
};

static const char *data_sources[] = {
	"Live", "Memory",
};

static GSList *scan(struct sr_dev_driver *di, GSList *options)
{
	struct drv_context *drvc;
	struct dev_context *devc;
	struct sr_dev_inst *sdi;
	struct sr_config *src;
	GSList *usb_devices, *devices, *l;
	unsigned int i;
	const char *conn;

	drvc = di->context;

	conn = "1a86.e008";
	for (l = options; l; l = l->next) {
		src = l->data;
		switch (src->key) {
		case SR_CONF_CONN:
			conn = g_variant_get_string(src->data, NULL);
			break;
		}
	}
	if (!conn)
		return NULL;

	devices = NULL;
	if ((usb_devices = sr_usb_find(drvc->sr_ctx->libusb_ctx, conn))) {
		/* We have a list of sr_usb_dev_inst matching the connection
		 * string. Wrap them in sr_dev_inst and we're done. */
		for (l = usb_devices; l; l = l->next) {
			sdi = g_malloc0(sizeof(struct sr_dev_inst));
			sdi->status = SR_ST_INACTIVE;
			sdi->vendor = g_strdup("UNI-T");
			sdi->model = g_strdup("UT32x");
			sdi->inst_type = SR_INST_USB;
			sdi->conn = l->data;
			for (i = 0; i < ARRAY_SIZE(channel_names); i++)
				sr_channel_new(sdi, i, SR_CHANNEL_ANALOG, TRUE,
						channel_names[i]);
			devc = g_malloc0(sizeof(struct dev_context));
			sdi->priv = devc;
			sr_sw_limits_init(&devc->limits);
			devc->data_source = DEFAULT_DATA_SOURCE;
			devices = g_slist_append(devices, sdi);
		}
		g_slist_free(usb_devices);
	} else
		g_slist_free_full(usb_devices, g_free);

	return std_scan_complete(di, devices);
}

static int dev_open(struct sr_dev_inst *sdi)
{
	struct sr_dev_driver *di = sdi->driver;
	struct drv_context *drvc = di->context;
	struct sr_usb_dev_inst *usb;
	int ret;

	usb = sdi->conn;

	if (sr_usb_open(drvc->sr_ctx->libusb_ctx, usb) != SR_OK)
		return SR_ERR;

/*
 * The libusb 1.0.9 Darwin backend is broken: it can report a kernel
 * driver being active, but detaching it always returns an error.
 */
#if !defined(__APPLE__)
	if (libusb_kernel_driver_active(usb->devhdl, USB_INTERFACE) == 1) {
		if ((ret = libusb_detach_kernel_driver(usb->devhdl, USB_INTERFACE)) < 0) {
			sr_err("failed to detach kernel driver: %s",
					libusb_error_name(ret));
			return SR_ERR;
		}
	}
#endif

	if ((ret = libusb_set_configuration(usb->devhdl, USB_CONFIGURATION))) {
		sr_err("Failed to set configuration: %s.", libusb_error_name(ret));
		return SR_ERR;
	}

	if ((ret = libusb_claim_interface(usb->devhdl, USB_INTERFACE))) {
		sr_err("Failed to claim interface: %s.", libusb_error_name(ret));
		return SR_ERR;
	}

	return SR_OK;
}

static int dev_close(struct sr_dev_inst *sdi)
{
	struct sr_usb_dev_inst *usb;

	usb = sdi->conn;

	if (!usb->devhdl)
		return SR_ERR_BUG;

	libusb_release_interface(usb->devhdl, USB_INTERFACE);
	libusb_close(usb->devhdl);
	usb->devhdl = NULL;

	return SR_OK;
}

static int config_get(uint32_t key, GVariant **data,
	const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
{
	struct dev_context *devc;

	(void)cg;

	devc = sdi->priv;
	switch (key) {
	case SR_CONF_LIMIT_SAMPLES:
	case SR_CONF_LIMIT_MSEC:
		return sr_sw_limits_config_get(&devc->limits, key, data);
	case SR_CONF_DATA_SOURCE:
		*data = g_variant_new_string(data_sources[devc->data_source]);
		break;
	default:
		return SR_ERR_NA;
	}

	return SR_OK;
}

static int config_set(uint32_t key, GVariant *data,
	const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
{
	struct dev_context *devc;
	int idx;

	(void)cg;

	devc = sdi->priv;

	switch (key) {
	case SR_CONF_LIMIT_SAMPLES:
	case SR_CONF_LIMIT_MSEC:
		return sr_sw_limits_config_set(&devc->limits, key, data);
	case SR_CONF_DATA_SOURCE:
		if ((idx = std_str_idx(data, ARRAY_AND_SIZE(data_sources))) < 0)
			return SR_ERR_ARG;
		devc->data_source = idx;
		break;
	default:
		return SR_ERR_NA;
	}

	return SR_OK;
}

static int config_list(uint32_t key, GVariant **data,
	const struct sr_dev_inst *sdi, const struct sr_channel_group *cg)
{
	switch (key) {
	case SR_CONF_SCAN_OPTIONS:
	case SR_CONF_DEVICE_OPTIONS:
		return STD_CONFIG_LIST(key, data, sdi, cg, scanopts, drvopts, devopts);
	case SR_CONF_DATA_SOURCE:
		*data = g_variant_new_strv(ARRAY_AND_SIZE(data_sources));
		break;
	default:
		return SR_ERR_NA;
	}

	return SR_OK;
}

static int dev_acquisition_start(const struct sr_dev_inst *sdi)
{
	struct sr_dev_driver *di = sdi->driver;
	struct drv_context *drvc;
	struct dev_context *devc;
	struct sr_usb_dev_inst *usb;
	int len, ret;
	unsigned char cmd[2];

	drvc = di->context;
	devc = sdi->priv;
	usb = sdi->conn;

	sr_sw_limits_acquisition_start(&devc->limits);
	devc->packet_len = 0;

	/* Configure serial port parameters on USB-UART interface
	 * chip inside the device (just baudrate 2400 actually). */
	cmd[0] = 0x09;
	cmd[1] = 0x60;
	ret = libusb_control_transfer(usb->devhdl, 0x21, 0x09, 0x0300, 0x00,
			cmd, 2, 5);
	if (ret != 2) {
		sr_dbg("Failed to configure CH9325: %s", libusb_error_name(ret));
		return SR_ERR;
	}

	std_session_send_df_header(sdi);

	if (!(devc->xfer = libusb_alloc_transfer(0)))
		return SR_ERR;

	/* Length of payload to follow. */
	cmd[0] = 0x01;
	if (devc->data_source == DATA_SOURCE_LIVE)
		cmd[1] = CMD_GET_LIVE;
	else
		cmd[1] = CMD_GET_STORED;

	ret = libusb_bulk_transfer(usb->devhdl, EP_OUT, cmd, 2, &len, 5);
	if (ret != 0 || len != 2) {
		sr_dbg("Failed to start acquisition: %s", libusb_error_name(ret));
		libusb_free_transfer(devc->xfer);
		return SR_ERR;
	}

	libusb_fill_bulk_transfer(devc->xfer, usb->devhdl, EP_IN, devc->buf,
			8, uni_t_ut32x_receive_transfer, (void *)sdi, 15);
	if (libusb_submit_transfer(devc->xfer) != 0) {
		libusb_free_transfer(devc->xfer);
		return SR_ERR;
	}

	usb_source_add(sdi->session, drvc->sr_ctx, 10,
			uni_t_ut32x_handle_events, (void *)sdi);

	return SR_OK;
}

static int dev_acquisition_stop(struct sr_dev_inst *sdi)
{
	/* Signal USB transfer handler to clean up and stop. */
	sdi->status = SR_ST_STOPPING;

	return SR_OK;
}

static struct sr_dev_driver uni_t_ut32x_driver_info = {
	.name = "uni-t-ut32x",
	.longname = "UNI-T UT32x",
	.api_version = 1,
	.init = std_init,
	.cleanup = std_cleanup,
	.scan = scan,
	.dev_list = std_dev_list,
	.dev_clear = std_dev_clear,
	.config_get = config_get,
	.config_set = config_set,
	.config_list = config_list,
	.dev_open = dev_open,
	.dev_close = dev_close,
	.dev_acquisition_start = dev_acquisition_start,
	.dev_acquisition_stop = dev_acquisition_stop,
	.context = NULL,
};
SR_REGISTER_DEV_DRIVER(uni_t_ut32x_driver_info);
