/* Copyright 2017 Jason Williams (Wilba)
 *
 * 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 2 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 "keymap.h" // to get keymaps[][][]
#include "tmk_core/common/eeprom.h"
#include "progmem.h" // to read default from flash
#include "quantum.h" // for send_string()
#include "dynamic_keymap.h"

#ifdef DYNAMIC_KEYMAP_ENABLE

#ifndef DYNAMIC_KEYMAP_EEPROM_ADDR
#error DYNAMIC_KEYMAP_EEPROM_ADDR not defined
#endif

#ifndef DYNAMIC_KEYMAP_LAYER_COUNT
#error DYNAMIC_KEYMAP_LAYER_COUNT not defined
#endif

#ifndef DYNAMIC_KEYMAP_MACRO_COUNT
#error DYNAMIC_KEYMAP_MACRO_COUNT not defined
#endif

#ifndef DYNAMIC_KEYMAP_MACRO_EEPROM_ADDR
#error DYNAMIC_KEYMAP_MACRO_EEPROM_ADDR not defined
#endif

#ifndef DYNAMIC_KEYMAP_MACRO_EEPROM_SIZE
#error DYNAMIC_KEYMAP_MACRO_EEPROM_SIZE not defined
#endif

uint8_t dynamic_keymap_get_layer_count(void)
{
	return DYNAMIC_KEYMAP_LAYER_COUNT;
}

void *dynamic_keymap_key_to_eeprom_address(uint8_t layer, uint8_t row, uint8_t column)
{
	// TODO: optimize this with some left shifts
	return ((void*)DYNAMIC_KEYMAP_EEPROM_ADDR) + ( layer * MATRIX_ROWS * MATRIX_COLS * 2 ) +
		( row * MATRIX_COLS * 2 ) + ( column * 2 );
}

uint16_t dynamic_keymap_get_keycode(uint8_t layer, uint8_t row, uint8_t column)
{
	void *address = dynamic_keymap_key_to_eeprom_address(layer, row, column);
	// Big endian, so we can read/write EEPROM directly from host if we want
	uint16_t keycode = eeprom_read_byte(address) << 8;
	keycode |= eeprom_read_byte(address + 1);
	return keycode;
}

void dynamic_keymap_set_keycode(uint8_t layer, uint8_t row, uint8_t column, uint16_t keycode)
{
	void *address = dynamic_keymap_key_to_eeprom_address(layer, row, column);
	// Big endian, so we can read/write EEPROM directly from host if we want
	eeprom_update_byte(address, (uint8_t)(keycode >> 8));
	eeprom_update_byte(address+1, (uint8_t)(keycode & 0xFF));
}

void dynamic_keymap_reset(void)
{
	// Reset the keymaps in EEPROM to what is in flash.
	// All keyboards using dynamic keymaps should define a layout
	// for the same number of layers as DYNAMIC_KEYMAP_LAYER_COUNT.
	for ( int layer = 0; layer < DYNAMIC_KEYMAP_LAYER_COUNT; layer++ )	{
		for ( int row = 0; row < MATRIX_ROWS; row++ ) {
			for ( int column = 0; column < MATRIX_COLS; column++ )	{
				dynamic_keymap_set_keycode(layer, row, column, pgm_read_word(&keymaps[layer][row][column]));
			}
		}
	}
}

void dynamic_keymap_get_buffer( uint16_t offset, uint16_t size, uint8_t *data )
{
	uint16_t dynamic_keymap_eeprom_size = DYNAMIC_KEYMAP_LAYER_COUNT * MATRIX_ROWS * MATRIX_COLS * 2;
	void *source = (void*)(DYNAMIC_KEYMAP_EEPROM_ADDR+offset);
	uint8_t *target = data;
	for ( uint16_t i = 0; i < size; i++ ) {
		if ( offset + i < dynamic_keymap_eeprom_size ) {
			*target = eeprom_read_byte(source);
		} else {
			*target = 0x00;
		}
		source++;
		target++;
	}
}

void dynamic_keymap_set_buffer( uint16_t offset, uint16_t size, uint8_t *data )
{
	uint16_t dynamic_keymap_eeprom_size = DYNAMIC_KEYMAP_LAYER_COUNT * MATRIX_ROWS * MATRIX_COLS * 2;
	void *target = (void*)(DYNAMIC_KEYMAP_EEPROM_ADDR+offset);
	uint8_t *source = data;
	for ( uint16_t i = 0; i < size; i++ ) {
		if ( offset + i < dynamic_keymap_eeprom_size ) {
			eeprom_update_byte(target, *source);
		}
		source++;
		target++;
	}
}

// This overrides the one in quantum/keymap_common.c
uint16_t keymap_key_to_keycode(uint8_t layer, keypos_t key)
{
	if ( layer < DYNAMIC_KEYMAP_LAYER_COUNT &&
			key.row < MATRIX_ROWS &&
			key.col < MATRIX_COLS ) {
		return dynamic_keymap_get_keycode(layer, key.row, key.col);
	} else {
		return KC_NO;
	}
}



uint8_t dynamic_keymap_macro_get_count(void)
{
	return DYNAMIC_KEYMAP_MACRO_COUNT;
}

uint16_t dynamic_keymap_macro_get_buffer_size(void)
{
	return DYNAMIC_KEYMAP_MACRO_EEPROM_SIZE;
}

void dynamic_keymap_macro_get_buffer( uint16_t offset, uint16_t size, uint8_t *data )
{
	void *source = (void*)(DYNAMIC_KEYMAP_MACRO_EEPROM_ADDR+offset);
	uint8_t *target = data;
	for ( uint16_t i = 0; i < size; i++ ) {
		if ( offset + i < DYNAMIC_KEYMAP_MACRO_EEPROM_SIZE ) {
			*target = eeprom_read_byte(source);
		} else {
			*target = 0x00;
		}
		source++;
		target++;
	}
}

void dynamic_keymap_macro_set_buffer( uint16_t offset, uint16_t size, uint8_t *data )
{
	void *target = (void*)(DYNAMIC_KEYMAP_MACRO_EEPROM_ADDR+offset);
	uint8_t *source = data;
	for ( uint16_t i = 0; i < size; i++ ) {
		if ( offset + i < DYNAMIC_KEYMAP_MACRO_EEPROM_SIZE ) {
			eeprom_update_byte(target, *source);
		}
		source++;
		target++;
	}
}

void dynamic_keymap_macro_reset(void)
{
	void *p = (void*)(DYNAMIC_KEYMAP_MACRO_EEPROM_ADDR);
	void *end = (void*)(DYNAMIC_KEYMAP_MACRO_EEPROM_ADDR+DYNAMIC_KEYMAP_MACRO_EEPROM_SIZE);
	while ( p != end ) {
		eeprom_update_byte(p, 0);
		++p;
	}
}

void dynamic_keymap_macro_send( uint8_t id )
{
	if ( id >= DYNAMIC_KEYMAP_MACRO_COUNT )	{
		return;
	}

	// Check the last byte of the buffer.
	// If it's not zero, then we are in the middle
	// of buffer writing, possibly an aborted buffer
	// write. So do nothing.
	void *p = (void*)(DYNAMIC_KEYMAP_MACRO_EEPROM_ADDR+DYNAMIC_KEYMAP_MACRO_EEPROM_SIZE-1);
	if ( eeprom_read_byte(p) != 0 )	{
		return;
	}

	// Skip N null characters
	// p will then point to the Nth macro
	p = (void*)(DYNAMIC_KEYMAP_MACRO_EEPROM_ADDR);
	void *end = (void*)(DYNAMIC_KEYMAP_MACRO_EEPROM_ADDR+DYNAMIC_KEYMAP_MACRO_EEPROM_SIZE);
	while ( id > 0 ) {
		// If we are past the end of the buffer, then the buffer
		// contents are garbage, i.e. there were not DYNAMIC_KEYMAP_MACRO_COUNT
		// nulls in the buffer.
		if ( p == end ) {
			return;
		}
		if ( eeprom_read_byte(p) == 0 ) {
			--id;
		}
		++p;
	}

	// Send the macro string one or two chars at a time
	// by making temporary 1 or 2 char strings
	char data[3] = { 0, 0, 0 };
	// We already checked there was a null at the end of
	// the buffer, so this cannot go past the end
	while ( 1 ) {
		data[0] = eeprom_read_byte(p++);
		data[1] = 0;
		// Stop at the null terminator of this macro string
		if ( data[0] == 0 ) {
			break;
		}
		// If the char is magic (tap, down, up),
		// add the next char (key to use) and send a 2 char string.
		if ( data[0] == SS_TAP_CODE || data[0] == SS_DOWN_CODE || data[0] == SS_UP_CODE ) {
			data[1] = eeprom_read_byte(p++);
			if ( data[1] == 0 ) {
				break;
			}
		}
		send_string(data);
	}
}

#endif // DYNAMIC_KEYMAP_ENABLE