/*
 * UPEK TouchChip driver for libfprint
 * Copyright (C) 2013 Vasily Khoruzhick <anarsoul@gmail.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#define FP_COMPONENT "upektc_img"

#include "drivers_api.h"
#include "upek_proto.h"
#include "upektc_img.h"

static void start_capture(FpImageDevice *dev);
static void start_deactivation(FpImageDevice *dev);

#define EP_IN			(1 | FPI_USB_ENDPOINT_IN)
#define EP_OUT			(2 | FPI_USB_ENDPOINT_OUT)
#define CTRL_TIMEOUT		4000
#define BULK_TIMEOUT		4000

#define IMAGE_WIDTH		144
#define IMAGE_HEIGHT		384
#define IMAGE_SIZE		(IMAGE_WIDTH * IMAGE_HEIGHT)

#define MAX_CMD_SIZE		64
#define MAX_RESPONSE_SIZE	2052
#define SHORT_RESPONSE_SIZE	64

struct _FpiDeviceUpektcImg {
	FpImageDevice parent;

	unsigned char cmd[MAX_CMD_SIZE];
	unsigned char response[MAX_RESPONSE_SIZE];
	unsigned char *image_bits;
	unsigned char seq;
	size_t image_size;
	size_t response_rest;
	gboolean deactivating;
};
G_DECLARE_FINAL_TYPE(FpiDeviceUpektcImg, fpi_device_upektc_img, FPI,
		     DEVICE_UPEKTC_IMG, FpImageDevice);
G_DEFINE_TYPE(FpiDeviceUpektcImg, fpi_device_upektc_img, FP_TYPE_IMAGE_DEVICE);

/****** HELPERS ******/

static void upektc_img_cmd_fix_seq(unsigned char *cmd_buf, unsigned char seq)
{
	uint8_t byte;

	byte = cmd_buf[5];
	byte &= 0x0f;
	byte |= (seq << 4);
	cmd_buf[5] = byte;
}

static void upektc_img_cmd_update_crc(unsigned char *cmd_buf, size_t size)
{
	/* CRC does not cover Ciao prefix (4 bytes) and CRC location (2 bytes) */
	uint16_t crc = udf_crc(cmd_buf + 4, size - 6);

	cmd_buf[size - 2] = (crc & 0x00ff);
	cmd_buf[size - 1] = (crc & 0xff00) >> 8;
}

static void
upektc_img_submit_req(FpiSsm               *ssm,
		      FpImageDevice     *dev,
		      const unsigned char   *buf,
		      size_t                 buf_size,
		      unsigned char          seq,
		      FpiUsbTransferCallback  cb)
{
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(dev);
	FpiUsbTransfer *transfer = fpi_usb_transfer_new(FP_DEVICE(dev));

	BUG_ON(buf_size > MAX_CMD_SIZE);

	memcpy(self->cmd, buf, buf_size);
	upektc_img_cmd_fix_seq(self->cmd, seq);
	upektc_img_cmd_update_crc(self->cmd, buf_size);

	fpi_usb_transfer_fill_bulk_full(transfer, EP_OUT, self->cmd, buf_size,
				       NULL);
	transfer->ssm = ssm;
	transfer->short_is_error = TRUE;
	fpi_usb_transfer_submit(transfer, BULK_TIMEOUT, NULL, cb, NULL);
	fpi_usb_transfer_unref(transfer);
}

static void
upektc_img_read_data(FpiSsm               *ssm,
		     FpImageDevice     *dev,
		     size_t                 buf_size,
		     size_t                 buf_offset,
		     FpiUsbTransferCallback  cb)
{
	FpiUsbTransfer *transfer = fpi_usb_transfer_new(FP_DEVICE(dev));
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(dev);

	BUG_ON(buf_offset + buf_size > MAX_RESPONSE_SIZE);

	fpi_usb_transfer_fill_bulk_full(transfer, EP_IN,
				       self->response + buf_offset, buf_size,
				       NULL);
	transfer->ssm = ssm;
	fpi_usb_transfer_submit(transfer, BULK_TIMEOUT, NULL, cb, NULL);
	fpi_usb_transfer_unref(transfer);
}

/****** CAPTURE ******/

enum capture_states {
	CAPTURE_INIT_CAPTURE,
	CAPTURE_READ_DATA,
	CAPTURE_READ_DATA_TERM,
	CAPTURE_ACK_00_28,
	CAPTURE_ACK_08,
	CAPTURE_ACK_FRAME,
	CAPTURE_ACK_00_28_TERM,
	CAPTURE_NUM_STATES,
};

static void capture_reqs_cb(FpiUsbTransfer *transfer, FpDevice *device,
			    gpointer user_data, GError *error)
{
	if (error) {
		fpi_ssm_mark_failed(transfer->ssm, error);
		return;
	}
	switch (fpi_ssm_get_cur_state(transfer->ssm)) {
	case CAPTURE_ACK_00_28_TERM:
		fpi_ssm_jump_to_state(transfer->ssm, CAPTURE_READ_DATA_TERM);
		break;
	default:
		fpi_ssm_jump_to_state(transfer->ssm, CAPTURE_READ_DATA);
		break;
	}
}

static int upektc_img_process_image_frame(unsigned char *image_buf, unsigned char *cmd_res)
{
	int offset = 8;
	int len = ((cmd_res[5] & 0x0f) << 8) | (cmd_res[6]);

	len -= 1;
	if (cmd_res[7] == 0x2c) {
		len -= 10;
		offset += 10;
	}
	if (cmd_res[7] == 0x20) {
		len -= 4;
	}
	memcpy(image_buf, cmd_res + offset, len);

	return len;
}

static void capture_read_data_cb(FpiUsbTransfer *transfer, FpDevice *device,
				 gpointer user_data, GError *error)
{
	FpImageDevice *dev = FP_IMAGE_DEVICE(device);
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(dev);
	unsigned char *data = self->response;
	FpImage *img;
	size_t response_size;

	if (error) {
		fp_dbg("request is not completed, %s", error->message);
		fpi_ssm_mark_failed(transfer->ssm, error);
		return;
	}

	if (self->deactivating) {
		fp_dbg("Deactivate requested\n");
		fpi_ssm_mark_completed(transfer->ssm);
		return;
	}

	fp_dbg("request completed, len: %.4x", (gint)transfer->actual_length);
	if (transfer->actual_length == 0) {
		fpi_ssm_jump_to_state(transfer->ssm,
				     fpi_ssm_get_cur_state(transfer->ssm));
		return;
	}

	if (fpi_ssm_get_cur_state(transfer->ssm) == CAPTURE_READ_DATA_TERM) {
		fp_dbg("Terminating SSM\n");
		fpi_ssm_mark_completed(transfer->ssm);
		return;
	}

	if (!self->response_rest) {
		response_size = ((data[5] & 0x0f) << 8) + data[6];
		response_size += 9; /* 7 bytes for header, 2 for CRC */
		if (response_size > transfer->actual_length) {
			fp_dbg("response_size is %lu, actual_length is %d\n",
				response_size, (gint)transfer->actual_length);
			fp_dbg("Waiting for rest of transfer");
			BUG_ON(self->response_rest);
			self->response_rest = response_size - transfer->actual_length;
			fpi_ssm_jump_to_state(transfer->ssm, CAPTURE_READ_DATA);
			return;
		}
	}
	self->response_rest = 0;

	switch (data[4]) {
	case 0x00:
		switch (data[7]) {
			/* No finger */
			case 0x28:
				fp_dbg("18th byte is %.2x\n", data[18]);
				switch (data[18]) {
				case 0x0c:
					/* no finger */
					fpi_ssm_jump_to_state(transfer->ssm,
							     CAPTURE_ACK_00_28);
					break;
				case 0x00:
					/* finger is present! */
					fpi_ssm_jump_to_state(transfer->ssm,
							     CAPTURE_ACK_00_28);
					break;
				case 0x1e:
					/* short scan */
					fp_err("short scan, aborting\n");
					fpi_image_device_retry_scan(dev,
							      FP_DEVICE_RETRY_TOO_SHORT);
					fpi_image_device_report_finger_status(dev,
									      FALSE);
					fpi_ssm_jump_to_state(transfer->ssm,
							     CAPTURE_ACK_00_28_TERM);
					break;
				case 0x1d:
					/* too much horisontal movement */
					fp_err("too much horisontal movement, aborting\n");
					fpi_image_device_retry_scan(dev,
							      FP_DEVICE_RETRY_CENTER_FINGER);
					fpi_image_device_report_finger_status(dev,
									      FALSE);
					fpi_ssm_jump_to_state(transfer->ssm,
							     CAPTURE_ACK_00_28_TERM);
					break;
				default:
					/* some error happened, cancel scan */
					fp_err("something bad happened, stop scan\n");
					fpi_image_device_retry_scan(dev,
							      FP_DEVICE_RETRY);
					fpi_image_device_report_finger_status(dev,
									      FALSE);
					fpi_ssm_jump_to_state(transfer->ssm,
							     CAPTURE_ACK_00_28_TERM);
					break;
				}
				break;
			/* Image frame with additional info */
			case 0x2c:
				fpi_image_device_report_finger_status(dev,
								      TRUE);
			/* Plain image frame */
			case 0x24:
				self->image_size +=
					upektc_img_process_image_frame(self->image_bits + self->image_size,
								       data);
				fpi_ssm_jump_to_state(transfer->ssm,
						     CAPTURE_ACK_FRAME);
				break;
			/* Last image frame */
			case 0x20:
				self->image_size +=
					upektc_img_process_image_frame(self->image_bits + self->image_size,
								       data);
				BUG_ON(self->image_size != IMAGE_SIZE);
				fp_dbg("Image size is %lu\n",
				       self->image_size);
				img = fp_image_new(IMAGE_WIDTH, IMAGE_HEIGHT);
				memcpy(img->data, self->image_bits,
				       IMAGE_SIZE);
				fpi_image_device_image_captured(dev, img);
				fpi_image_device_report_finger_status(dev,
								      FALSE);
				fpi_ssm_mark_completed(transfer->ssm);
				break;
			default:
				fp_err("Unknown response!\n");
				fpi_ssm_mark_failed(transfer->ssm, fpi_device_error_new (FP_DEVICE_ERROR_GENERAL));
				break;
		}
		break;
	case 0x08:
		fpi_ssm_jump_to_state(transfer->ssm, CAPTURE_ACK_08);
		break;
	default:
		fp_err("Not handled response!\n");
		fpi_ssm_mark_failed(transfer->ssm, fpi_device_error_new (FP_DEVICE_ERROR_GENERAL));
	}
}

static void capture_run_state(FpiSsm *ssm, FpDevice *_dev, void *user_data)
{
	FpImageDevice *dev = user_data;
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(_dev);

	switch (fpi_ssm_get_cur_state(ssm)) {
	case CAPTURE_INIT_CAPTURE:
		upektc_img_submit_req(ssm, dev, upek2020_init_capture, sizeof(upek2020_init_capture),
			self->seq, capture_reqs_cb);
			self->seq++;
		break;
	case CAPTURE_READ_DATA:
	case CAPTURE_READ_DATA_TERM:
		if (!self->response_rest)
			upektc_img_read_data(ssm, dev, SHORT_RESPONSE_SIZE, 0, capture_read_data_cb);
		else
			upektc_img_read_data(ssm, dev, MAX_RESPONSE_SIZE - SHORT_RESPONSE_SIZE,
			SHORT_RESPONSE_SIZE, capture_read_data_cb);
		break;
	case CAPTURE_ACK_00_28:
	case CAPTURE_ACK_00_28_TERM:
		upektc_img_submit_req(ssm, dev, upek2020_ack_00_28, sizeof(upek2020_ack_00_28),
			self->seq, capture_reqs_cb);
			self->seq++;
		break;
	case CAPTURE_ACK_08:
		upektc_img_submit_req(ssm, dev, upek2020_ack_08, sizeof(upek2020_ack_08),
			0, capture_reqs_cb);
		break;
	case CAPTURE_ACK_FRAME:
		upektc_img_submit_req(ssm, dev, upek2020_ack_frame, sizeof(upek2020_ack_frame),
			self->seq, capture_reqs_cb);
			self->seq++;
		break;
	};
}

static void capture_sm_complete(FpiSsm *ssm, FpDevice *_dev, void *user_data, GError *error_arg)
{
	FpImageDevice *dev = user_data;
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(_dev);
	g_autoptr(GError) error = error_arg;

	fpi_ssm_free(ssm);

	/* Note: We assume that the error is a cancellation in the deactivation case */
	if (self->deactivating)
		start_deactivation(dev);
	else if (error)
		fpi_image_device_session_error (dev, g_steal_pointer (&error));
	else
		start_capture(dev);
}

static void start_capture(FpImageDevice *dev)
{
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(dev);
	FpiSsm *ssm;

	self->image_size = 0;

	ssm = fpi_ssm_new(FP_DEVICE(dev), capture_run_state,
			 CAPTURE_NUM_STATES, dev);
	fpi_ssm_start(ssm, capture_sm_complete);
}

/****** INITIALIZATION/DEINITIALIZATION ******/

enum deactivate_states {
	DEACTIVATE_DEINIT,
	DEACTIVATE_READ_DEINIT_DATA,
	DEACTIVATE_NUM_STATES,
};

static void deactivate_reqs_cb(FpiUsbTransfer *transfer, FpDevice *device,
			       gpointer user_data, GError *error)
{
	if (!error) {
		fpi_ssm_jump_to_state(transfer->ssm, CAPTURE_READ_DATA);
	} else {
		fpi_ssm_mark_failed(transfer->ssm, error);
	}
}

/* TODO: process response properly */
static void deactivate_read_data_cb(FpiUsbTransfer *transfer, FpDevice *device,
				    gpointer user_data, GError *error)
{
	if (!error) {
		fpi_ssm_mark_completed(transfer->ssm);
	} else {
		fpi_ssm_mark_failed(transfer->ssm, error);
	}
}

static void deactivate_run_state(FpiSsm *ssm, FpDevice *_dev,
				 void *user_data)
{
	FpImageDevice *dev = user_data;
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(_dev);

	switch (fpi_ssm_get_cur_state(ssm)) {
	case DEACTIVATE_DEINIT:
		upektc_img_submit_req(ssm, dev, upek2020_deinit, sizeof(upek2020_deinit),
			self->seq, deactivate_reqs_cb);
		self->seq++;
		break;
	case DEACTIVATE_READ_DEINIT_DATA:
		upektc_img_read_data(ssm, dev, SHORT_RESPONSE_SIZE, 0, deactivate_read_data_cb);
		break;
	};
}

static void deactivate_sm_complete(FpiSsm *ssm, FpDevice *_dev,
				   void *user_data, GError *error)
{
	FpImageDevice *dev = user_data;
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(_dev);

	fp_dbg("Deactivate completed");
	fpi_ssm_free(ssm);

	self->deactivating = FALSE;
	fpi_image_device_deactivate_complete(dev,  error);
}

static void start_deactivation(FpImageDevice *dev)
{
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(dev);
	FpiSsm *ssm;

	self->image_size = 0;

	ssm = fpi_ssm_new(FP_DEVICE(dev), deactivate_run_state,
			 DEACTIVATE_NUM_STATES, dev);
	fpi_ssm_start(ssm, deactivate_sm_complete);
}

enum activate_states {
	ACTIVATE_CONTROL_REQ_1,
	ACTIVATE_READ_CTRL_RESP_1,
	ACTIVATE_INIT_1,
	ACTIVATE_READ_INIT_1_RESP,
	ACTIVATE_INIT_2,
	ACTIVATE_READ_INIT_2_RESP,
	ACTIVATE_CONTROL_REQ_2,
	ACTIVATE_READ_CTRL_RESP_2,
	ACTIVATE_INIT_3,
	ACTIVATE_READ_INIT_3_RESP,
	ACTIVATE_INIT_4,
	ACTIVATE_READ_INIT_4_RESP,
	ACTIVATE_NUM_STATES,
};

static void init_reqs_ctrl_cb(FpiUsbTransfer *transfer, FpDevice *device,
			      gpointer user_data, GError *error)
{
	if (!error) {
		fpi_ssm_next_state(transfer->ssm);
	} else {
		fpi_ssm_mark_failed(transfer->ssm, error);
	}
}

static void init_reqs_cb(FpiUsbTransfer *transfer, FpDevice *device,
			 gpointer user_data, GError *error)
{
	if (!error) {
		fpi_ssm_next_state(transfer->ssm);
	} else {
		fpi_ssm_mark_failed(transfer->ssm, error);
	}
}

/* TODO: process response properly */
static void init_read_data_cb(FpiUsbTransfer *transfer, FpDevice *device,
			      gpointer user_data, GError *error)
{
	if (!error) {
		fpi_ssm_next_state(transfer->ssm);
	} else {
		fpi_ssm_mark_failed(transfer->ssm, error);
	}
}

static void activate_run_state(FpiSsm *ssm, FpDevice *dev, void *user_data)
{
	FpiUsbTransfer *transfer;
	FpImageDevice *idev = user_data;
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(dev);

	switch (fpi_ssm_get_cur_state(ssm)) {
	case ACTIVATE_CONTROL_REQ_1:
	case ACTIVATE_CONTROL_REQ_2:
	{
		transfer = fpi_usb_transfer_new(dev);

		fpi_usb_transfer_fill_control(transfer,
					     G_USB_DEVICE_DIRECTION_HOST_TO_DEVICE,
					     G_USB_DEVICE_REQUEST_TYPE_VENDOR,
					     G_USB_DEVICE_RECIPIENT_DEVICE,
					     0x0c, 0x100, 0x0400, 1);
		transfer->buffer[0] = '\0';
		transfer->ssm = ssm;
		fpi_usb_transfer_submit(transfer, CTRL_TIMEOUT, NULL,
				       init_reqs_ctrl_cb, NULL);
		fpi_usb_transfer_unref(transfer);
	}
	break;
	case ACTIVATE_INIT_1:
		upektc_img_submit_req(ssm, idev, upek2020_init_1, sizeof(upek2020_init_1),
			0, init_reqs_cb);
	break;
	case ACTIVATE_INIT_2:
		upektc_img_submit_req(ssm, idev, upek2020_init_2, sizeof(upek2020_init_2),
			0, init_reqs_cb);
	break;
	case ACTIVATE_INIT_3:
		upektc_img_submit_req(ssm, idev, upek2020_init_3, sizeof(upek2020_init_3),
			0, init_reqs_cb);
	break;
	case ACTIVATE_INIT_4:
		upektc_img_submit_req(ssm, idev, upek2020_init_4, sizeof(upek2020_init_4),
			self->seq, init_reqs_cb);
		/* Seq should be updated after 4th init */
		self->seq++;
	break;
	case ACTIVATE_READ_CTRL_RESP_1:
	case ACTIVATE_READ_CTRL_RESP_2:
	case ACTIVATE_READ_INIT_1_RESP:
	case ACTIVATE_READ_INIT_2_RESP:
	case ACTIVATE_READ_INIT_3_RESP:
	case ACTIVATE_READ_INIT_4_RESP:
		upektc_img_read_data(ssm, idev, SHORT_RESPONSE_SIZE, 0, init_read_data_cb);
	break;
	}
}

static void activate_sm_complete(FpiSsm *ssm, FpDevice *_dev,
				 void *user_data, GError *error)
{
	FpImageDevice *dev = user_data;

	fpi_ssm_free(ssm);
	fpi_image_device_activate_complete(dev, error);

	if (!error)
		start_capture(dev);
}

static void dev_activate(FpImageDevice *dev)
{
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(dev);
	FpiSsm *ssm = fpi_ssm_new(FP_DEVICE(dev), activate_run_state,
				  ACTIVATE_NUM_STATES, dev);
	self->seq = 0;
	fpi_ssm_start(ssm, activate_sm_complete);
}

static void dev_deactivate(FpImageDevice *dev)
{
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(dev);

	self->deactivating = TRUE;
}

static void dev_init(FpImageDevice *dev)
{
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(dev);
	GError *error = NULL;
	/* TODO check that device has endpoints we're using */

	if (!g_usb_device_claim_interface(fpi_device_get_usb_device(FP_DEVICE(dev)), 0, 0, &error)) {
		fpi_image_device_open_complete(dev, error);
		return;
	}

	self->image_bits = g_malloc0 (IMAGE_SIZE * 2);
	fpi_image_device_open_complete(dev, NULL);
}

static void dev_deinit(FpImageDevice *dev)
{
	FpiDeviceUpektcImg *self = FPI_DEVICE_UPEKTC_IMG(dev);
	GError *error = NULL;

	g_clear_pointer (&self->image_bits, g_free);
	g_usb_device_release_interface(fpi_device_get_usb_device(FP_DEVICE(dev)),
				       0, 0, &error);
	fpi_image_device_close_complete(dev, error);
}

static int
discover(GUsbDevice *usb_device)
{
	gint16 pid = g_usb_device_get_pid (usb_device);
	gint16 bcd = g_usb_device_get_release (usb_device);

	if (pid == 0x2020 && bcd == 1)
		return 100;
	if (pid == 0x2016 && bcd == 2)
		return 100;

	return 0;
}

static const FpIdEntry id_table [ ] = {
	{ .vid = 0x147e,  .pid = 0x2016,
	},
	{ .vid = 0x147e,  .pid = 0x2020,
	},
	{ .vid = 0,  .pid = 0,  .driver_data = 0 },
};

static void fpi_device_upektc_img_init(FpiDeviceUpektcImg *self) {
}
static void fpi_device_upektc_img_class_init(FpiDeviceUpektcImgClass *klass) {
	FpDeviceClass *dev_class = FP_DEVICE_CLASS(klass);
	FpImageDeviceClass *img_class = FP_IMAGE_DEVICE_CLASS(klass);

	dev_class->id = "upektc_img";
	dev_class->full_name = "Upek TouchChip Fingerprint Coprocessor";
	dev_class->type = FP_DEVICE_TYPE_USB;
	dev_class->id_table = id_table;
	dev_class->scan_type = FP_SCAN_TYPE_SWIPE;
	dev_class->usb_discover = discover;

	img_class->img_open = dev_init;
	img_class->img_close = dev_deinit;
	img_class->activate = dev_activate;
	img_class->deactivate = dev_deactivate;

	img_class->bz3_threshold = 20;

	img_class->img_width = IMAGE_WIDTH;
	img_class->img_height = IMAGE_HEIGHT;
}