/*

Note to self: adapted from ergodox EZ matrix
The "column" and "row" in here actually refers to the opposite on the keyboard
see definition of KEYMAP in v1.h, the grid is transposed so that a "row" in here is actually a "column" on the physical keyboard
Nicolas

Copyright 2013 Oleg Kostyuk <cub.uanic@gmail.com>
Copyright 2013 Nicolas Poirey <nicolas.poirey@gmail.com>

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/>.
*/

/*
 * scan matrix
 */
#include <stdint.h>
#include <stdbool.h>
#include <avr/io.h>
#include "wait.h"
#include "action_layer.h"
#include "print.h"
#include "debug.h"
#include "util.h"
#include "matrix.h"
#include "frenchdev.h"

/*
 * This constant define not debouncing time in msecs, but amount of matrix
 * scan loops which should be made to get stable debounced results.
 *
 * On Ergodox matrix scan rate is relatively low, because of slow I2C.
 * Now it's only 317 scans/second, or about 3.15 msec/scan.
 * According to Cherry specs, debouncing time is 5 msec.
 *
 * And so, there is no sense to have DEBOUNCE higher than 2.
 */

#ifndef DEBOUNCE
#   define DEBOUNCE	5
#endif
static uint8_t debouncing = DEBOUNCE;

/* matrix state(1:on, 0:off) */
static matrix_row_t matrix[MATRIX_ROWS];
static matrix_row_t matrix_debouncing[MATRIX_ROWS];

static matrix_row_t read_cols(uint8_t row);
static void init_cols(void);
static void unselect_rows(void);
static void select_row(uint8_t row);

static uint8_t mcp23018_reset_loop;

__attribute__ ((weak))
void matrix_init_user(void) {}

__attribute__ ((weak))
void matrix_scan_user(void) {}

__attribute__ ((weak))
void matrix_init_kb(void) {
  matrix_init_user();
}

__attribute__ ((weak))
void matrix_scan_kb(void) {
  matrix_scan_user();
}

inline
uint8_t matrix_rows(void)
{
    return MATRIX_ROWS;
}

inline
uint8_t matrix_cols(void)
{
    return MATRIX_COLS;
}

void matrix_init(void)
{
    // initialize row and col
    debug_enable = true;
    debug_matrix = true;
    debug_keyboard = true;
    debug_mouse = true;

    mcp23018_status = init_mcp23018();


    unselect_rows();
    init_cols();

    // initialize matrix state: all keys off
    for (uint8_t i=0; i < MATRIX_ROWS; i++) {
        matrix[i] = 0;
        matrix_debouncing[i] = 0;
    }

    matrix_init_quantum();
}

void matrix_power_up(void) {
    mcp23018_status = init_mcp23018();

    unselect_rows();
    init_cols();

    // initialize matrix state: all keys off
    for (uint8_t i=0; i < MATRIX_ROWS; i++) {
        matrix[i] = 0;
        matrix_debouncing[i] = 0;
    }
}

uint8_t matrix_scan(void)
{
    if (mcp23018_status) { // if there was an error
        if (++mcp23018_reset_loop == 0) {
            // since mcp23018_reset_loop is 8 bit - we'll try to reset once in 255 matrix scans
            // this will be approx bit more frequent than once per second
            print("trying to reset mcp23018\n");
            mcp23018_status = init_mcp23018();
            if (mcp23018_status) {
                print("left side not responding\n");
            } else {
                print("left side attached\n");
                frenchdev_blink_all_leds();
            }
        }
    }

    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
        select_row(i);
        wait_us(30);  // without this wait read unstable value.
        matrix_row_t cols = read_cols(i);
        if (matrix_debouncing[i] != cols) {
            matrix_debouncing[i] = cols;
            if (debouncing) {
                debug("bounce!: "); debug_hex(debouncing); debug("\n");
            }
            debouncing = DEBOUNCE;
        }
        unselect_rows();
    }

    if (debouncing) {
        if (--debouncing) {
            wait_us(1);
            // this should be wait_ms(1) but has been left as-is at EZ's request
        } else {
            for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
                matrix[i] = matrix_debouncing[i];
            }
        }
    }

    matrix_scan_quantum();

    return 1;
}

bool matrix_is_modified(void)
{
    if (debouncing) return false;
    return true;
}

inline
bool matrix_is_on(uint8_t row, uint8_t col)
{
    return (matrix[row] & ((matrix_row_t)1<<col));
}

inline
matrix_row_t matrix_get_row(uint8_t row)
{
    return matrix[row];
}

void matrix_print(void)
{
    print("\nr/c 0123456789ABCDEF\n");
    for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
        print_hex8(row); print(": ");
        print_bin_reverse16(matrix_get_row(row));
        print("\n");
    }
}

uint8_t matrix_key_count(void)
{
    uint8_t count = 0;
    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
        count += bitpop16(matrix[i]);
    }
    return count;
}

/* Column pin configuration
 *
 * Teensy
 * col: 0   1   2   3   4   5
 * pin: F0  F1  F4  F5  F6  F7
 *
 * MCP23018
 * col: 0   1   2   3   4   5
 * pin: B5  B4  B3  B2  B1  B0
 */
static void  init_cols(void)
{
    // init on mcp23018
    // not needed, already done as part of init_mcp23018()

    // init on teensy
    // Input with pull-up(DDR:0, PORT:1)
    DDRF  &= ~(1<<7 | 1<<6 | 1<<5 | 1<<4 | 1<<1 | 1<<0);
    PORTF |=  (1<<7 | 1<<6 | 1<<5 | 1<<4 | 1<<1 | 1<<0);
}

static matrix_row_t read_cols(uint8_t row)
{
    if (row < 8) {
        if (mcp23018_status) { // if there was an error
            return 0;
        } else {
            uint8_t data = 0;
            mcp23018_status = i2c_start(I2C_ADDR_WRITE, I2C_TIMEOUT);   if (mcp23018_status) goto out;
            mcp23018_status = i2c_write(GPIOB, I2C_TIMEOUT);            if (mcp23018_status) goto out;
            mcp23018_status = i2c_start(I2C_ADDR_READ, I2C_TIMEOUT);    if (mcp23018_status) goto out;
            data = i2c_read_nack(I2C_TIMEOUT);                         if (mcp23018_status < 0) goto out;
            data = ~((uint8_t)mcp23018_status);
            mcp23018_status = I2C_STATUS_SUCCESS;
        out:
            i2c_stop();
            return data;
        }
    } else {
        // read from teensy
        return
            (PINF&(1<<0) ? 0 : (1<<0)) |
            (PINF&(1<<1) ? 0 : (1<<1)) |
            (PINF&(1<<4) ? 0 : (1<<2)) |
            (PINF&(1<<5) ? 0 : (1<<3)) |
            (PINF&(1<<6) ? 0 : (1<<4)) |
            (PINF&(1<<7) ? 0 : (1<<5)) ;
    }
}

/* Row pin configuration
 *
 * Teensy
 * row: 7   8   9   10  11  12  13
 * pin: B0  B1  B2  B3  D2  D3  C6
 *
 * MCP23018
 * row: 0   1   2   3   4   5   6
 * pin: A0  A1  A2  A3  A4  A5  A6
 */
static void unselect_rows(void)
{
    // unselect on mcp23018
    if (mcp23018_status) { // if there was an error
        // do nothing
    } else {
        // set all rows hi-Z : 1
        mcp23018_status = i2c_start(I2C_ADDR_WRITE, I2C_TIMEOUT);    if (mcp23018_status) goto out;
        mcp23018_status = i2c_write(GPIOA, I2C_TIMEOUT);             if (mcp23018_status) goto out;
        mcp23018_status = i2c_write( 0xFF & ~(0<<8), I2C_TIMEOUT);   if (mcp23018_status) goto out;
    out:
        i2c_stop();
    }

    // unselect on teensy
    // Hi-Z(DDR:0, PORT:0) to unselect
    DDRB  &= ~(1<<0 | 1<<1 | 1<<2 | 1<<3);
    PORTB &= ~(1<<0 | 1<<1 | 1<<2 | 1<<3);
    DDRD  &= ~(1<<2 | 1<<3);
    PORTD &= ~(1<<2 | 1<<3);
    DDRC  &= ~(1<<6 | 1<<7);
    PORTC &= ~(1<<6 | 1<<7);
}

static void select_row(uint8_t row)
{
    if (row < 8) {
        // select on mcp23018
        if (mcp23018_status) { // if there was an error
            // do nothing
        } else {
            // set active row low  : 0
            // set other rows hi-Z : 1
            mcp23018_status = i2c_start(I2C_ADDR_WRITE, I2C_TIMEOUT);                          if (mcp23018_status) goto out;
            mcp23018_status = i2c_write(GPIOA, I2C_TIMEOUT);                                   if (mcp23018_status) goto out;
            mcp23018_status = i2c_write( 0xFF & ~(1<<row) & ~(0<<8), I2C_TIMEOUT);             if (mcp23018_status) goto out;
        out:
            i2c_stop();
        }
    } else {
        // select on teensy
        // Output low(DDR:1, PORT:0) to select
        switch (row) {
            case 8:
                DDRB  |= (1<<0);
                PORTB &= ~(1<<0);
                break;
            case 9:
                DDRB  |= (1<<1);
                PORTB &= ~(1<<1);
                break;
            case 10:
                DDRB  |= (1<<2);
                PORTB &= ~(1<<2);
                break;
            case 11:
                DDRB  |= (1<<3);
                PORTB &= ~(1<<3);
                break;
            case 12:
                DDRD  |= (1<<2);
                PORTD &= ~(1<<3);
                break;
            case 13:
                DDRD  |= (1<<3);
                PORTD &= ~(1<<3);
                break;
            case 14:
                DDRC  |= (1<<6);
                PORTC &= ~(1<<6);
                break;
            case 15:
                DDRC  |= (1<<7);
                PORTC &= ~(1<<7);
                break;
        }
    }
}