/*
Copyright 2012 Jun Wako <wakojun@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 "wait.h"
#include "util.h"
#include "matrix.h"
#include "split_util.h"
#include "config.h"
#include "split_flags.h"
#include "quantum.h"
#include "debounce.h"
#include "transport.h"

#if (MATRIX_COLS <= 8)
#  define print_matrix_header() print("\nr/c 01234567\n")
#  define print_matrix_row(row) print_bin_reverse8(matrix_get_row(row))
#  define matrix_bitpop(i) bitpop(matrix[i])
#  define ROW_SHIFTER ((uint8_t)1)
#elif (MATRIX_COLS <= 16)
#  define print_matrix_header() print("\nr/c 0123456789ABCDEF\n")
#  define print_matrix_row(row) print_bin_reverse16(matrix_get_row(row))
#  define matrix_bitpop(i) bitpop16(matrix[i])
#  define ROW_SHIFTER ((uint16_t)1)
#elif (MATRIX_COLS <= 32)
#  define print_matrix_header() print("\nr/c 0123456789ABCDEF0123456789ABCDEF\n")
#  define print_matrix_row(row) print_bin_reverse32(matrix_get_row(row))
#  define matrix_bitpop(i) bitpop32(matrix[i])
#  define ROW_SHIFTER ((uint32_t)1)
#endif

#define ERROR_DISCONNECT_COUNT 5

//#define ROWS_PER_HAND (MATRIX_ROWS / 2)

#ifdef DIRECT_PINS
static pin_t direct_pins[MATRIX_ROWS][MATRIX_COLS] = DIRECT_PINS;
#else
static pin_t row_pins[MATRIX_ROWS] = MATRIX_ROW_PINS;
static pin_t col_pins[MATRIX_COLS] = MATRIX_COL_PINS;
#endif

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

// row offsets for each hand
uint8_t thisHand, thatHand;

// user-defined overridable functions

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

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

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

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

__attribute__((weak)) void matrix_slave_scan_user(void) {}

// helper functions

inline uint8_t matrix_rows(void) { return MATRIX_ROWS; }

inline uint8_t matrix_cols(void) { return MATRIX_COLS; }

bool matrix_is_modified(void) {
  if (debounce_active()) 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_matrix_header();

  for (uint8_t row = 0; row < MATRIX_ROWS; row++) {
    print_hex8(row);
    print(": ");
    print_matrix_row(row);
    print("\n");
  }
}

uint8_t matrix_key_count(void) {
  uint8_t count = 0;
  for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
    count += matrix_bitpop(i);
  }
  return count;
}

// matrix code

#ifdef DIRECT_PINS

static void init_pins(void) {
  for (int row = 0; row < MATRIX_ROWS; row++) {
    for (int col = 0; col < MATRIX_COLS; col++) {
      pin_t pin = direct_pins[row][col];
      if (pin != NO_PIN) {
        setPinInputHigh(pin);
      }
    }
  }
}

static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row) {
  matrix_row_t last_row_value = current_matrix[current_row];
  current_matrix[current_row] = 0;

  for (uint8_t col_index = 0; col_index < MATRIX_COLS; col_index++) {
    pin_t pin = direct_pins[current_row][col_index];
    if (pin != NO_PIN) {
      current_matrix[current_row] |= readPin(pin) ? 0 : (ROW_SHIFTER << col_index);
    }
  }

  return (last_row_value != current_matrix[current_row]);
}

#elif (DIODE_DIRECTION == COL2ROW)

static void select_row(uint8_t row) {
  setPinOutput(row_pins[row]);
  writePinLow(row_pins[row]);
}

static void unselect_row(uint8_t row) { setPinInputHigh(row_pins[row]); }

static void unselect_rows(void) {
  for (uint8_t x = 0; x < ROWS_PER_HAND; x++) {
    setPinInputHigh(row_pins[x]);
  }
}

static void init_pins(void) {
  unselect_rows();
  for (uint8_t x = 0; x < MATRIX_COLS; x++) {
    setPinInputHigh(col_pins[x]);
  }
}

static bool read_cols_on_row(matrix_row_t current_matrix[], uint8_t current_row) {
  // Store last value of row prior to reading
  matrix_row_t last_row_value = current_matrix[current_row];

  // Clear data in matrix row
  current_matrix[current_row] = 0;

  // Select row and wait for row selecton to stabilize
  select_row(current_row);
  wait_us(30);

  // For each col...
  for (uint8_t col_index = 0; col_index < MATRIX_COLS; col_index++) {
    // Populate the matrix row with the state of the col pin
    current_matrix[current_row] |= readPin(col_pins[col_index]) ? 0 : (ROW_SHIFTER << col_index);
  }

  // Unselect row
  unselect_row(current_row);

  return (last_row_value != current_matrix[current_row]);
}

#elif (DIODE_DIRECTION == ROW2COL)

static void select_col(uint8_t col) {
  setPinOutput(col_pins[col]);
  writePinLow(col_pins[col]);
}

static void unselect_col(uint8_t col) { setPinInputHigh(col_pins[col]); }

static void unselect_cols(void) {
  for (uint8_t x = 0; x < MATRIX_COLS; x++) {
    setPinInputHigh(col_pins[x]);
  }
}

static void init_pins(void) {
  unselect_cols();
  for (uint8_t x = 0; x < ROWS_PER_HAND; x++) {
    setPinInputHigh(row_pins[x]);
  }
}

static bool read_rows_on_col(matrix_row_t current_matrix[], uint8_t current_col) {
  bool matrix_changed = false;

  // Select col and wait for col selecton to stabilize
  select_col(current_col);
  wait_us(30);

  // For each row...
  for (uint8_t row_index = 0; row_index < ROWS_PER_HAND; row_index++) {
    // Store last value of row prior to reading
    matrix_row_t last_row_value = current_matrix[row_index];

    // Check row pin state
    if (readPin(row_pins[row_index])) {
      // Pin HI, clear col bit
      current_matrix[row_index] &= ~(ROW_SHIFTER << current_col);
    } else {
      // Pin LO, set col bit
      current_matrix[row_index] |= (ROW_SHIFTER << current_col);
    }

    // Determine if the matrix changed state
    if ((last_row_value != current_matrix[row_index]) && !(matrix_changed)) {
      matrix_changed = true;
    }
  }

  // Unselect col
  unselect_col(current_col);

  return matrix_changed;
}

#endif

void matrix_init(void) {
  debug_enable = true;
  debug_matrix = true;
  debug_mouse  = true;

  // Set pinout for right half if pinout for that half is defined
  if (!isLeftHand) {
#ifdef MATRIX_ROW_PINS_RIGHT
    const uint8_t row_pins_right[MATRIX_ROWS] = MATRIX_ROW_PINS_RIGHT;
    for (uint8_t i = 0; i < MATRIX_ROWS; i++) {
      row_pins[i] = row_pins_right[i];
    }
#endif
#ifdef MATRIX_COL_PINS_RIGHT
    const uint8_t col_pins_right[MATRIX_COLS] = MATRIX_COL_PINS_RIGHT;
    for (uint8_t i = 0; i < MATRIX_COLS; i++) {
      col_pins[i] = col_pins_right[i];
    }
#endif
  }

  thisHand = isLeftHand ? 0 : (ROWS_PER_HAND);
  thatHand = ROWS_PER_HAND - thisHand;

  // initialize key pins
  init_pins();

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

  debounce_init(ROWS_PER_HAND);

  matrix_init_quantum();
}

uint8_t _matrix_scan(void) {
  bool changed = false;

#if defined(DIRECT_PINS) || (DIODE_DIRECTION == COL2ROW)
  // Set row, read cols
  for (uint8_t current_row = 0; current_row < ROWS_PER_HAND; current_row++) {
    changed |= read_cols_on_row(raw_matrix, current_row);
  }
#elif (DIODE_DIRECTION == ROW2COL)
  // Set col, read rows
  for (uint8_t current_col = 0; current_col < MATRIX_COLS; current_col++) {
    changed |= read_rows_on_col(raw_matrix, current_col);
  }
#endif

  debounce(raw_matrix, matrix + thisHand, ROWS_PER_HAND, changed);

  return 1;
}

uint8_t matrix_scan(void) {
  uint8_t ret = _matrix_scan();

  if (is_keyboard_master()) {
    static uint8_t error_count;

    if (!transport_master(matrix + thatHand)) {
      error_count++;

      if (error_count > ERROR_DISCONNECT_COUNT) {
        // reset other half if disconnected
        for (int i = 0; i < ROWS_PER_HAND; ++i) {
          matrix[thatHand + i] = 0;
        }
      }
    } else {
      error_count = 0;
    }

    matrix_scan_quantum();
  } else {
    transport_slave(matrix + thisHand);
    matrix_slave_scan_user();
  }

  return ret;
}