/*
 * This file is part of the libsigrok project.
 *
 * Copyright (C) 2012 Martin Ling <martin-git@earth.li>
 *
 * 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 <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <glib.h>
#include "libsigrok.h"
#include "libsigrok-internal.h"
#include "protocol.h"

#define NUM_PROBES 2

static const int hwcaps[] = {
	SR_HWCAP_OSCILLOSCOPE,
	SR_HWCAP_LIMIT_SAMPLES,
	SR_HWCAP_TIMEBASE,
	SR_HWCAP_TRIGGER_SOURCE,
	SR_HWCAP_TRIGGER_SLOPE,
	SR_HWCAP_HORIZ_TRIGGERPOS,
	SR_HWCAP_VDIV,
	SR_HWCAP_COUPLING,
	0,
};

static const char *probe_names[] = {
	"CH1", "CH2",
	NULL,
};

static const struct sr_rational timebases[] = {
	/* nanoseconds */
	{ 2, 1000000000 },
	{ 5, 1000000000 },
	{ 10, 1000000000 },
	{ 20, 1000000000 },
	{ 50, 1000000000 },
	{ 100, 1000000000 },
	{ 500, 1000000000 },
	/* microseconds */
	{ 1, 1000000 },
	{ 2, 1000000 },
	{ 5, 1000000 },
	{ 10, 1000000 },
	{ 20, 1000000 },
	{ 50, 1000000 },
	{ 100, 1000000 },
	{ 200, 1000000 },
	{ 500, 1000000 },
	/* milliseconds */
	{ 1, 1000 },
	{ 2, 1000 },
	{ 5, 1000 },
	{ 10, 1000 },
	{ 20, 1000 },
	{ 50, 1000 },
	{ 100, 1000 },
	{ 200, 1000 },
	{ 500, 1000 },
	/* seconds */
	{ 1, 1 },
	{ 2, 1 },
	{ 5, 1 },
	{ 10, 1 },
	{ 20, 1 },
	{ 50, 1 },
	{ 0, 0},
};

static const struct sr_rational vdivs[] = {
	/* millivolts */
	{ 2, 1000 },
	{ 5, 1000 },
	{ 10, 1000 },
	{ 20, 1000 },
	{ 50, 1000 },
	{ 100, 1000 },
	{ 200, 1000 },
	{ 500, 1000 },
	/* volts */
	{ 1, 1 },
	{ 2, 1 },
	{ 5, 1 },
	{ 10, 1 },
	{ 0, 0 },
};

static const char *trigger_sources[] = {
	"CH1",
	"CH2",
	"EXT",
	"AC Line",
	NULL,
};

static const char *coupling[] = {
	"AC",
	"DC",
	"GND",
	NULL,
};

SR_PRIV struct sr_dev_driver rigol_ds1xx2_driver_info;
static struct sr_dev_driver *di = &rigol_ds1xx2_driver_info;

/* Properly close and free all devices. */
static int clear_instances(void)
{
	struct sr_dev_inst *sdi;
	struct drv_context *drvc;
	struct dev_context *devc;
	GSList *l;

	if (!(drvc = di->priv))
		return SR_OK;

	for (l = drvc->instances; l; l = l->next) {
		if (!(sdi = l->data))
			continue;
		if (!(devc = sdi->priv))
			continue;

		close(devc->fd);

		sr_dev_inst_free(sdi);
	}

	g_slist_free(drvc->instances);
	drvc->instances = NULL;

	return SR_OK;
}

static int hw_init(struct sr_context *sr_ctx)
{
	struct drv_context *drvc;
	(void)sr_ctx;

	if (!(drvc = g_try_malloc0(sizeof(struct drv_context)))) {
		sr_err("Driver context malloc failed.");
		return SR_ERR_MALLOC;
	}

	di->priv = drvc;

	return SR_OK;
}

static GSList *hw_scan(GSList *options)
{
	struct drv_context *drvc;
	struct sr_dev_inst *sdi;
	struct dev_context *devc;
	struct sr_probe *probe;
	GSList *devices;
	int i;

	(void)options;

	devices = NULL;
	drvc = di->priv;
	drvc->instances = NULL;

	if (!(sdi = sr_dev_inst_new(0, SR_ST_ACTIVE, "Rigol", "DS1xx2", NULL)))
		return NULL;
	if (!(devc = g_try_malloc0(sizeof(struct dev_context))))
		return NULL;

	sdi->priv = devc;
	sdi->driver = di;

	for (i = 0; i < 2; i++)
	{
		if (!(probe = sr_probe_new(0, SR_PROBE_ANALOG, TRUE, i == 0 ? "CH1" : "CH2")))
			return NULL;
		sdi->probes = g_slist_append(sdi->probes, probe);
	}
	drvc->instances = g_slist_append(drvc->instances, sdi);
	devices = g_slist_append(devices, sdi);

	return devices;
}

static GSList *hw_dev_list(void)
{
	struct drv_context *drvc;

	drvc = di->priv;

	return drvc->instances;
}

static int hw_dev_open(struct sr_dev_inst *sdi)
{
	int fd = open("/dev/usbtmc1", O_RDWR);

	if (fd == -1)
		return SR_ERR;

	struct dev_context *devc = sdi->priv;
	devc->fd = fd;

	devc->scale = 1;

	return SR_OK;
}

static int hw_dev_close(struct sr_dev_inst *sdi)
{
	struct dev_context *devc = sdi->priv;

	close(devc->fd);

	return SR_OK;
}

static int hw_cleanup(void)
{
	clear_instances();

	return SR_OK;
}

static int hw_info_get(int info_id, const void **data,
		       const struct sr_dev_inst *sdi)
{
	(void)sdi;

	switch (info_id) {
	case SR_DI_HWCAPS:
		*data = hwcaps;
		break;
	case SR_DI_NUM_PROBES:
		*data = GINT_TO_POINTER(NUM_PROBES);
		break;
	case SR_DI_PROBE_NAMES:
		*data = probe_names;
		break;
	case SR_DI_TIMEBASES:
		*data = timebases;
		break;
	case SR_DI_TRIGGER_SOURCES:
		*data = trigger_sources;
		break;
	case SR_DI_VDIVS:
		*data = vdivs;
		break;
	case SR_DI_COUPLING:
		*data = coupling;
		break;
	default:
		sr_err("Unknown info_id: %d.", info_id);
		return SR_ERR_ARG;
	}

	return SR_OK;
}

static int hw_dev_config_set(const struct sr_dev_inst *sdi, int hwcap,
			     const void *value)
{
	struct dev_context *devc = sdi->priv;
	uint64_t tmp_u64;
	float tmp_float;
	struct sr_rational tmp_rat;
	int ret, i, j;
	char *channel;

	if (sdi->status != SR_ST_ACTIVE) {
		sr_err("Device inactive, can't set config options.");
		return SR_ERR;
	}

	ret = SR_OK;
	switch (hwcap) {
    case SR_HWCAP_LIMIT_FRAMES:
		devc->limit_frames = *(const uint64_t *)value;
		break;
	case SR_HWCAP_TRIGGER_SLOPE:
		tmp_u64 = *(const int *)value;
		rigol_ds1xx2_send_data(devc->fd, "TRIG:EDGE:%s\n", tmp_u64 ? "POS" : "NEG");
		break;
	case SR_HWCAP_HORIZ_TRIGGERPOS:
		tmp_float = *(const float *)value;
		rigol_ds1xx2_send_data(devc->fd, "TIM:OFFS %f\n", tmp_float);
		break;
	case SR_HWCAP_TIMEBASE:
		tmp_rat = *(const struct sr_rational *)value;
		rigol_ds1xx2_send_data(devc->fd, "TIM:SCAL %f\n", (float) tmp_rat.p / tmp_rat.q);
		break;
	case SR_HWCAP_TRIGGER_SOURCE:
		if (!strcmp(value, "CH1"))
			channel = "CHAN1";
		else if (!strcmp(value, "CH2"))
			channel = "CHAN2";
		else if (!strcmp(value, "EXT"))
			channel = "EXT";
		else if (!strcmp(value, "AC Line"))
			channel = "ACL";
		else
			ret = SR_ERR_ARG;
			break;
		rigol_ds1xx2_send_data(devc->fd, "TRIG:SOUR %s\n", channel);
		break;
	case SR_HWCAP_VDIV:
		/* TODO: Not supporting vdiv per channel yet. */
		tmp_rat = *(const struct sr_rational *)value;
		for (i = 0; vdivs[i].p && vdivs[i].q; i++) {
			if (vdivs[i].p == tmp_rat.p
					&& vdivs[i].q == tmp_rat.q) {
				devc->scale = (float) tmp_rat.p / tmp_rat.q;
				for (j = 0; j < 2; j++)
					rigol_ds1xx2_send_data(devc->fd, "CHAN%d:SCAL %f\n", j, devc->scale);
				break;
			}
		}
		if (vdivs[i].p == 0 && vdivs[i].q == 0)
			ret = SR_ERR_ARG;
		break;
	case SR_HWCAP_COUPLING:
		/* TODO: Not supporting coupling per channel yet. */
		for (i = 0; coupling[i]; i++) {
			if (!strcmp(value, coupling[i])) {
				for (j = 0; j < 2; j++)
					rigol_ds1xx2_send_data(devc->fd, "CHAN%d:COUP %s\n", j, coupling[i]);
				break;
			}
		}
		if (coupling[i] == 0)
			ret = SR_ERR_ARG;
		break;
	default:
		sr_err("Unknown hardware capability: %d.", hwcap);
		ret = SR_ERR_ARG;
	}

	return ret;
}

static int hw_dev_acquisition_start(const struct sr_dev_inst *sdi,
				    void *cb_data)
{
	struct dev_context *devc = sdi->priv;
	struct sr_datafeed_packet packet;
	struct sr_datafeed_header header;
	struct sr_datafeed_meta_analog meta;
	char buf[256];
	int len;
	(void)cb_data;

	devc->num_frames = 0;

	sr_source_add(devc->fd, G_IO_IN, 50, rigol_ds1xx2_receive_data, (void *)sdi);

	/* Send header packet to the session bus. */
	packet.type = SR_DF_HEADER;
	packet.payload = (unsigned char *)&header;
	header.feed_version = 1;
	gettimeofday(&header.starttime, NULL);
	sr_session_send(cb_data, &packet);

	/* Send metadata about the SR_DF_ANALOG packets to come. */
	packet.type = SR_DF_META_ANALOG;
	packet.payload = &meta;
	meta.num_probes = NUM_PROBES;
	sr_session_send(cb_data, &packet);

	rigol_ds1xx2_send_data(devc->fd, ":CHAN1:SCAL?\n");
	len = read(devc->fd, buf, sizeof(buf));
	buf[len] = 0;
	devc->scale = atof(buf);
	sr_dbg("scale is %f", devc->scale);
	rigol_ds1xx2_send_data(devc->fd, ":CHAN1:OFFS?\n");
	len = read(devc->fd, buf, sizeof(buf));
	buf[len] = 0;
	devc->offset = atof(buf);
	sr_dbg("offset is %f", devc->offset);
	rigol_ds1xx2_send_data(devc->fd, ":WAV:DATA?\n");

	return SR_OK;
}

static int hw_dev_acquisition_stop(struct sr_dev_inst *sdi, void *cb_data)
{
	struct dev_context *devc = sdi->priv;
	(void)cb_data;

	if (sdi->status != SR_ST_ACTIVE) {
		sr_err("Device inactive, can't stop acquisition.");
		return SR_ERR;
	}

	sr_source_remove(devc->fd);

	return SR_OK;
}

SR_PRIV struct sr_dev_driver rigol_ds1xx2_driver_info = {
	.name = "rigol-ds1xx2",
	.longname = "Rigol DS1xx2",
	.api_version = 1,
	.init = hw_init,
	.cleanup = hw_cleanup,
	.scan = hw_scan,
	.dev_list = hw_dev_list,
	.dev_clear = clear_instances,
	.dev_open = hw_dev_open,
	.dev_close = hw_dev_close,
	.info_get = hw_info_get,
	.dev_config_set = hw_dev_config_set,
	.dev_acquisition_start = hw_dev_acquisition_start,
	.dev_acquisition_stop = hw_dev_acquisition_stop,
	.priv = NULL,
};