/*
 * Copyright (c) 2011 Matej Klonfar
 * 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 libusbhid
 * @{
 */
/** @file
 * USB HID report data parser implementation.
 */
#include <usb/hid/hidparser.h>
#include <errno.h>
#include <stdio.h>
#include <malloc.h>
#include <mem.h>
#include <usb/debug.h>
#include <assert.h>

/*---------------------------------------------------------------------------*/
/*
 * Data translation private functions
 */
uint32_t usb_hid_report_tag_data_uint32(const uint8_t *data, size_t size);

int usb_hid_translate_data(usb_hid_report_field_t *item, const uint8_t *data);

uint32_t usb_hid_translate_data_reverse(usb_hid_report_field_t *item, 
	int32_t value);

int usb_pow(int a, int b);

/*---------------------------------------------------------------------------*/

// TODO: tohle ma bejt asi jinde
int usb_pow(int a, int b)
{
	switch(b) {
	case 0:
		return 1;
		break;
	case 1:
		return a;
		break;
	default:
		return a * usb_pow(a, b-1);
		break;
	}
}
/*---------------------------------------------------------------------------*/

/** Returns size of report of specified report id and type in items
 *
 * @param parser Opaque report parser structure
 * @param report_id 
 * @param type
 * @return Number of items in specified report
 */
size_t usb_hid_report_size(usb_hid_report_t *report, uint8_t report_id, 
                           usb_hid_report_type_t type)
{
	usb_hid_report_description_t *report_des;

	if(report == NULL) {
		return 0;
	}

	report_des = usb_hid_report_find_description (report, report_id, type);
	if(report_des == NULL){
		return 0;
	}
	else {
		return report_des->item_length;
	}
}

/** Returns size of report of specified report id and type in bytes
 *
 * @param parser Opaque report parser structure
 * @param report_id 
 * @param type
 * @return Number of items in specified report
 */
size_t usb_hid_report_byte_size(usb_hid_report_t *report, uint8_t report_id, 
                           usb_hid_report_type_t type)
{
	usb_hid_report_description_t *report_des;

	if(report == NULL) {
		return 0;
	}

	report_des = usb_hid_report_find_description (report, report_id, type);
	if(report_des == NULL){
		return 0;
	}
	else {
		if(report_id == 0) {			
			return ((report_des->bit_length + 7) / 8) ;
		}
		else {
			return 1 + ((report_des->bit_length + 7) / 8);
		}
	}
}
/*---------------------------------------------------------------------------*/

/** Parse and act upon a HID report.
 *
 * @see usb_hid_parse_report_descriptor
 *
 * @param parser Opaque HID report parser structure.
 * @param data Data for the report.
 * @return Error code.
 */ 
int usb_hid_parse_report(const usb_hid_report_t *report, const uint8_t *data, 
	size_t size, uint8_t *report_id)
{
	link_t *list_item;
	usb_hid_report_field_t *item;

	usb_hid_report_description_t *report_des;
	usb_hid_report_type_t type = USB_HID_REPORT_TYPE_INPUT;
	
	if(report == NULL) {
		return EINVAL;
	}

	if(report->use_report_ids != 0) {
		*report_id = data[0];
	}	
	else {
		*report_id = 0;
	}


	report_des = usb_hid_report_find_description(report, *report_id, type);
	if(report_des == NULL) {
		return EINVAL;
	}

	/* read data */
	list_item = report_des->report_items.next;	   
	while(list_item != &(report_des->report_items)) {

		item = list_get_instance(list_item, usb_hid_report_field_t, link);

		if(USB_HID_ITEM_FLAG_CONSTANT(item->item_flags) == 0) {
			
			if(USB_HID_ITEM_FLAG_VARIABLE(item->item_flags) == 0) {

				// array
				item->value = usb_hid_translate_data(item, data);
		
				item->usage = USB_HID_EXTENDED_USAGE(
					item->usages[item->value - item->physical_minimum]);
				item->usage_page = USB_HID_EXTENDED_USAGE_PAGE(
					item->usages[item->value - item->physical_minimum]);				

				usb_hid_report_set_last_item (item->collection_path, 
					USB_HID_TAG_CLASS_GLOBAL, item->usage_page);
				usb_hid_report_set_last_item (item->collection_path, 
				    USB_HID_TAG_CLASS_LOCAL, item->usage);
				
			}
			else {
				// variable item
				item->value = usb_hid_translate_data(item, data);				
			}				
		}
		list_item = list_item->next;
	}
	
	return EOK;
	
}

/*---------------------------------------------------------------------------*/
/**
 * Translate data from the report as specified in report descriptor item
 *
 * @param item Report descriptor item with definition of translation
 * @param data Data to translate
 * @return Translated data
 */
int usb_hid_translate_data(usb_hid_report_field_t *item, const uint8_t *data)
{
	int resolution;
	int offset;
	int part_size;
	
	int32_t value=0;
	int32_t mask;
	const uint8_t *foo;

	// now only shot tags are allowed
	if(item->size > 32) {
		return 0;
	}

	if((item->physical_minimum == 0) && (item->physical_maximum == 0)){
		item->physical_minimum = item->logical_minimum;
		item->physical_maximum = item->logical_maximum;			
	}
	

	if(item->physical_maximum == item->physical_minimum){
	    resolution = 1;
	}
	else {
	    resolution = (item->logical_maximum - item->logical_minimum) / 
		((item->physical_maximum - item->physical_minimum) * 
		(usb_pow(10,(item->unit_exponent))));
	}

	offset = item->offset;
	// FIXME
	if((size_t)(offset/8) != (size_t)((offset+item->size-1)/8)) {
		
		part_size = ((offset+item->size)%8);

		size_t i=0;
		for(i=(size_t)(offset/8); i<=(size_t)(offset+item->size-1)/8; i++){
			if(i == (size_t)(offset/8)) {
				// the higher one
				foo = data + i;
				mask =  ((1 << (item->size-part_size))-1);
				value = (*foo & mask) << part_size;
			}
			else if(i == ((offset+item->size-1)/8)){
				// the lower one
				foo = data + i;
				mask =  ((1 << part_size)-1) << (8-part_size);
				value += ((*foo & mask) >> (8-part_size));
			}
			else {
				value = value << 8;
				value += *(data + 1);
			}
		}
	}
	else {		
		foo = data+(offset/8);
		mask =  ((1 << item->size)-1) << (8-((offset%8)+item->size));
		value = (*foo & mask) >> (8-((offset%8)+item->size));
	}

	if((item->logical_minimum < 0) || (item->logical_maximum < 0)){
		value = USB_HID_UINT32_TO_INT32(value, item->size);
	}

	return (int)(((value - item->logical_minimum) / resolution) + item->physical_minimum);
	
}

/*---------------------------------------------------------------------------*/
/* OUTPUT API */

/** 
 * Allocates output report buffer for output report
 *
 * @param parser Report parsed structure
 * @param size Size of returned buffer
 * @param report_id Report id of created output report
 * @return Returns allocated output buffer for specified output
 */
uint8_t *usb_hid_report_output(usb_hid_report_t *report, size_t *size, 
	uint8_t report_id)
{
	if(report == NULL) {
		*size = 0;
		return NULL;
	}

	link_t *report_it = report->reports.next;
	usb_hid_report_description_t *report_des = NULL;
	while(report_it != &report->reports) {
		report_des = list_get_instance(report_it, 
			usb_hid_report_description_t, link);
		
		if((report_des->report_id == report_id) && 
			(report_des->type == USB_HID_REPORT_TYPE_OUTPUT)){
			break;
		}

		report_it = report_it->next;
	}

	if(report_des == NULL){
		*size = 0;
		return NULL;
	}
	else {
		*size = (report_des->bit_length + (8 - 1))/8;
		uint8_t *ret = malloc((*size) * sizeof(uint8_t));
		memset(ret, 0, (*size) * sizeof(uint8_t));
		return ret;
	}
}


/** Frees output report buffer
 *
 * @param output Output report buffer
 * @return void
 */
void usb_hid_report_output_free(uint8_t *output)

{
	if(output != NULL) {
		free (output);
	}
}

/** Makes the output report buffer for data given in the report structure
 *
 * @param parser Opaque report parser structure
 * @param path Usage path specifing which parts of output will be set
 * @param flags Usage path structure comparison flags
 * @param buffer Output buffer
 * @param size Size of output buffer
 * @return Error code
 */
int usb_hid_report_output_translate(usb_hid_report_t *report, 
	uint8_t report_id, uint8_t *buffer, size_t size)
{
	link_t *item;	
	int32_t value=0;
	int offset;
	int length;
	int32_t tmp_value;
	
	if(report == NULL) {
		return EINVAL;
	}

	if(report->use_report_ids != 0) {
		buffer[0] = report_id;		
	}

	usb_hid_report_description_t *report_des;
	report_des = usb_hid_report_find_description (report, report_id, 
		USB_HID_REPORT_TYPE_OUTPUT);
	
	if(report_des == NULL){
		return EINVAL;
	}

	usb_hid_report_field_t *report_item;	
	item = report_des->report_items.next;	
	while(item != &report_des->report_items) {
		report_item = list_get_instance(item, usb_hid_report_field_t, link);

		if(USB_HID_ITEM_FLAG_VARIABLE(report_item->item_flags) == 0) {
					
			// array
			value = usb_hid_translate_data_reverse(report_item, 
				report_item->value);

			offset = report_item->offset;
			length = report_item->size;
		}
		else {
			// variable item
			value  = usb_hid_translate_data_reverse(report_item, 
				report_item->value);

			offset = report_item->offset;
			length = report_item->size;
		}

		usb_log_debug("\ttranslated value: %x\n", value);

		if((offset/8) == ((offset+length-1)/8)) {
			// je to v jednom bytu
			if(((size_t)(offset/8) >= size) || 
				((size_t)(offset+length-1)/8) >= size) {
				break; // TODO ErrorCode
			}
			size_t shift = 8 - offset%8 - length;
			value = value << shift;							
			value = value & (((1 << length)-1) << shift);
				
			uint8_t mask = 0;
			mask = 0xff - (((1 << length) - 1) << shift);
			buffer[offset/8] = (buffer[offset/8] & mask) | value;
		}
		else {
			int i = 0;
			uint8_t mask = 0;
			for(i = (offset/8); i <= ((offset+length-1)/8); i++) {
				if(i == (offset/8)) {
					tmp_value = value;
					tmp_value = tmp_value & ((1 << (8-(offset%8)))-1);				
					tmp_value = tmp_value << (offset%8);
	
					mask = ~(((1 << (8-(offset%8)))-1) << (offset%8));
					buffer[i] = (buffer[i] & mask) | tmp_value;			
				}
				else if (i == ((offset + length -1)/8)) {
					
					value = value >> (length - ((offset + length) % 8));
					value = value & 
						((1 << (length - ((offset + length) % 8))) - 1);
				
					mask = (1 << (length - ((offset + length) % 8))) - 1;
					buffer[i] = (buffer[i] & mask) | value;
				}
				else {
					buffer[i] = value & (0xFF << i);
				}
			}
		}

		// reset value
		report_item->value = 0;
		
		item = item->next;
	}
	
	return EOK;
}

/*---------------------------------------------------------------------------*/
/**
 * Translate given data for putting them into the outoput report
 * @param item Report item structure
 * @param value Value to translate
 * @return ranslated value
 */
uint32_t usb_hid_translate_data_reverse(usb_hid_report_field_t *item, 
	int value)
{
	int ret=0;
	int resolution;

	if(USB_HID_ITEM_FLAG_CONSTANT(item->item_flags)) {
		ret = item->logical_minimum;
	}

	if((item->physical_minimum == 0) && (item->physical_maximum == 0)){
		item->physical_minimum = item->logical_minimum;
		item->physical_maximum = item->logical_maximum;			
	}
	
	// variable item
	if(item->physical_maximum == item->physical_minimum){
	    resolution = 1;
	}
	else {
	    resolution = (item->logical_maximum - item->logical_minimum) /
		((item->physical_maximum - item->physical_minimum) *
		(usb_pow(10,(item->unit_exponent))));
	}

	ret = ((value - item->physical_minimum) * resolution) + 
		item->logical_minimum;

	usb_log_debug("\tvalue(%x), resolution(%x), phymin(%x) logmin(%x), \
		ret(%x)\n", value, resolution, item->physical_minimum, 
		item->logical_minimum, ret);
	
	if((item->logical_minimum < 0) || (item->logical_maximum < 0)){
		return USB_HID_INT32_TO_UINT32(ret, item->size);
	}
	return (int32_t)0 + ret;
}

/*---------------------------------------------------------------------------*/
/**
 * Clones given state table
 *
 * @param item State table to clone
 * @return Pointer to the cloned item
 */
usb_hid_report_item_t *usb_hid_report_item_clone(
	const usb_hid_report_item_t *item)
{
	usb_hid_report_item_t *new_report_item;
	
	if(!(new_report_item = malloc(sizeof(usb_hid_report_item_t)))) {
		return NULL;
	}					
	memcpy(new_report_item,item, sizeof(usb_hid_report_item_t));
	link_initialize(&(new_report_item->link));

	return new_report_item;
}

/*---------------------------------------------------------------------------*/
/**
 * Function for sequence walking through the report. Returns next field in the
 * report or the first one when no field is given.
 *
 * @param report Searched report structure
 * @param field Current field. If NULL is given, the first one in the report
 * is returned. Otherwise the next one i nthe list is returned.
 * @param path Usage path specifying which fields wa are interested in. 
 * @param flags Flags defining mode of usage paths comparison
 * @param type Type of report we search.
 * @retval NULL if no field is founded
 * @retval Pointer to the founded report structure when founded
 */
usb_hid_report_field_t *usb_hid_report_get_sibling(usb_hid_report_t *report, 
	usb_hid_report_field_t *field, usb_hid_report_path_t *path, int flags, 
	usb_hid_report_type_t type)
{
	usb_hid_report_description_t *report_des = usb_hid_report_find_description(
		report, path->report_id, type);

	link_t *field_it;
	
	if(report_des == NULL){
		return NULL;
	}

	if(field == NULL){
		field_it = report_des->report_items.next;
	}
	else {
		field_it = field->link.next;
	}

	while(field_it != &report_des->report_items) {
		field = list_get_instance(field_it, usb_hid_report_field_t, link);

		if(USB_HID_ITEM_FLAG_CONSTANT(field->item_flags) == 0) {
			usb_hid_report_path_append_item (field->collection_path, 
				field->usage_page, field->usage);

			if(usb_hid_report_compare_usage_path(field->collection_path, path, 
				flags) == EOK){

				usb_hid_report_remove_last_item(field->collection_path);
				return field;
			}
			usb_hid_report_remove_last_item (field->collection_path);
		}
		field_it = field_it->next;
	}

	return NULL;
}

/*---------------------------------------------------------------------------*/
/**
 * Returns next report_id of report of specified type. If zero is given than
 * first report_id of specified type is returned (0 is not legal value for
 * repotr_id)
 *
 * @param report_id Current report_id, 0 if there is no current report_id
 * @param type Type of searched report
 * @param report Report structure inwhich we search
 * @retval 0 if report structure is null or there is no specified report
 * @retval report_id otherwise
 */
uint8_t usb_hid_get_next_report_id(usb_hid_report_t *report, 
	uint8_t report_id, usb_hid_report_type_t type)
{
	if(report == NULL){
		return 0;
	}

	usb_hid_report_description_t *report_des;
	link_t *report_it;
	
	if(report_id > 0) {
		report_it = usb_hid_report_find_description(report, report_id, 
			type)->link.next;		
	}
	else {
		report_it = report->reports.next;
	}

	while(report_it != &report->reports) {
		report_des = list_get_instance(report_it, 
			usb_hid_report_description_t, link);

		if(report_des->type == type){
			return report_des->report_id;
		}
	}

	return 0;
}

/*---------------------------------------------------------------------------*/
/**
 * Reset all local items in given state table
 *
 * @param report_item State table containing current state of report
 * descriptor parsing
 *
 * @return void
 */
void usb_hid_report_reset_local_items(usb_hid_report_item_t *report_item)
{
	if(report_item == NULL)	{
		return;
	}
	
	report_item->usages_count = 0;
	memset(report_item->usages, 0, USB_HID_MAX_USAGES);
	
	report_item->extended_usage_page = 0;
	report_item->usage_minimum = 0;
	report_item->usage_maximum = 0;
	report_item->designator_index = 0;
	report_item->designator_minimum = 0;
	report_item->designator_maximum = 0;
	report_item->string_index = 0;
	report_item->string_minimum = 0;
	report_item->string_maximum = 0;

	return;
}
/**
 * @}
 */