/*
 * Copyright (c) 2010 Vojtech Horky
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup libusbvirt usb
 * @{
 */
/** @file
 * @brief Main handler for virtual USB device.
 */
#include <devmap.h>
#include <fcntl.h>
#include <vfs/vfs.h>
#include <errno.h>
#include <stdlib.h>

#include "hub.h"
#include "device.h"
#include "private.h"

#define NAMESPACE "usb"

usbvirt_device_t *device = NULL;


static void handle_data_to_device(ipc_callid_t iid, ipc_call_t icall)
{
	usb_address_t address = IPC_GET_ARG1(icall);
	usb_endpoint_t endpoint = IPC_GET_ARG2(icall);
	
	if (address != device->address) {
		ipc_answer_0(iid, EADDRNOTAVAIL);
		return;
	}
	
	size_t len;
	void * buffer;
	int rc = async_data_write_accept(&buffer, false,
	    1, USB_MAX_PAYLOAD_SIZE,
	    0, &len);
	
	if (rc != EOK) {
		ipc_answer_0(iid, rc);
		return;
	}
	
	handle_incoming_data(endpoint, buffer, len);
	
	free(buffer);
	
	ipc_answer_0(iid, EOK);
}

static void callback_connection(ipc_callid_t iid, ipc_call_t *icall)
{
	ipc_answer_0(iid, EOK);
	
	while (true) {
		ipc_callid_t callid; 
		ipc_call_t call; 
		
		callid = async_get_call(&call);
		switch (IPC_GET_METHOD(call)) {
			case IPC_M_PHONE_HUNGUP:
				ipc_answer_0(callid, EOK);
				return;
			
			case IPC_M_USBVIRT_DATA_TO_DEVICE:
				handle_data_to_device(callid, call);
				break;
			
			default:
				ipc_answer_0(callid, EINVAL);
				break;
		}
	}
}

static void device_init(usbvirt_device_t *dev)
{
	dev->send_data = usbvirt_data_to_host;
	dev->state = USBVIRT_STATE_DEFAULT;
	dev->address = 0;
}

int usbvirt_data_to_host(struct usbvirt_device *dev,
    usb_endpoint_t endpoint, void *buffer, size_t size)
{
	int phone = dev->vhcd_phone_;
	
	if (phone < 0) {
		return EINVAL;
	}
	if ((buffer == NULL) || (size == 0)) {
		return EINVAL;
	}

	ipc_call_t answer_data;
	ipcarg_t answer_rc;
	aid_t req;
	int rc;
	
	req = async_send_2(phone,
	    IPC_M_USBVIRT_DATA_FROM_DEVICE,
	    dev->address,
	    endpoint,
	    &answer_data);
	
	rc = async_data_write_start(phone, buffer, size);
	if (rc != EOK) {
		async_wait_for(req, NULL);
		return rc;
	}
	
	async_wait_for(req, &answer_rc);
	rc = (int)answer_rc;
	if (rc != EOK) {
		return rc;
	}
	
	return EOK;
}

/** Create necessary phones for comunication with virtual HCD.
 * This function wraps following calls:
 * -# open <code>/dev/usb/<i>hcd_path</i></code> for reading
 * -# access phone of file opened in previous step
 * -# create callback through just opened phone
 * -# create handler for calling on data from host to function
 * -# return the (outgoing) phone
 *
 * @warning This function is wrapper for several actions and therefore
 * it is not possible - in case of error - to determine at which point
 * error occured.
 *
 * @param hcd_path HCD identification under devfs
 *     (without <code>/dev/usb/</code>).
 * @param device_id Internal device identification (used by HCD).
 * @param callback Handler for callbacks from HCD.
 * @return EOK on success or error code from errno.h.
 */
int usbvirt_connect(usbvirt_device_t *dev, const char *hcd_path)
{
	char dev_path[DEVMAP_NAME_MAXLEN + 1];
	snprintf(dev_path, DEVMAP_NAME_MAXLEN,
	    "/dev/%s/%s", NAMESPACE, hcd_path);
	
	int fd = open(dev_path, O_RDONLY);
	if (fd < 0) {
		return fd;
	}
	
	int hcd_phone = fd_phone(fd);
	
	if (hcd_phone < 0) {
		return hcd_phone;
	}
	
	ipcarg_t phonehash;
	int rc = ipc_connect_to_me(hcd_phone, 1, dev->device_id_, 0, &phonehash);
	if (rc != EOK) {
		return rc;
	}
	
	dev->vhcd_phone_ = hcd_phone;
	device_init(dev);
	
	device = dev;
	
	async_new_connection(phonehash, 0, NULL, callback_connection);
	
	return EOK;
}


int usbvirt_disconnect(void)
{
	ipc_hangup(device->vhcd_phone_);
	
	device = NULL;
	
	return EOK;
}


/**
 * @}
 */