#include "owi.h"
#include "delay.h"
#include <string.h>
#include <stdio.h>
#include "uart.h"

#ifndef OWI_STRONG_DRIVE_HIGH_US
#define OWI_STRONG_DRIVE_HIGH_US   5u
#endif

/* 내부 상태 */
static uint32_t bit_period_us = OWI_BIT_PERIOD_US;
static uint8_t  g_owi_timeout_latched = 0;

static uint16_t g_owi_last_timeout_byte_index = 0xFFFFu;
static uint8_t  g_owi_last_timeout_bit_index  = 0xFFu;

static uint16_t g_owi_current_read_byte_index = 0u;
static uint8_t  g_owi_current_read_bit_index  = 0u;

/* =========================================================
 * GPIO helpers (P70 / HW Open-Drain)
 * - LOW  : 출력 모드 + 0
 * - HIGH : 입력(Hi-Z)로 release
 * ========================================================= */
void GPIO_Clear(void)
{
    OWI_PORT_POM |= (uint8_t)OWI_PIN_MASK;
    OWI_PORT_P   &= (uint8_t)~OWI_PIN_MASK;
    OWI_PORT_PM  &= (uint8_t)~OWI_PIN_MASK;
}

void GPIO_Input(void)
{
    OWI_PORT_POM |= (uint8_t)OWI_PIN_MASK;
    OWI_PORT_P   |= (uint8_t)OWI_PIN_MASK;
    OWI_PORT_PM  |= (uint8_t)OWI_PIN_MASK;
}

int GPIO_Read(void)
{
    return (OWI_PORT_P & (uint8_t)OWI_PIN_MASK) ? 1 : 0;
}

static void OWI_Release(void)
{
    OWI_PORT_POM |= (uint8_t)OWI_PIN_MASK;
    OWI_PORT_P   |= (uint8_t)OWI_PIN_MASK;
    OWI_PORT_PM  |= (uint8_t)OWI_PIN_MASK;
}

static void GPIO_StrongDriveHighKick(uint32_t kick_us)
{
    /* 1) 우선 release 상태 */
    OWI_Release();

    /* 2) 라인이 LOW면 강제 HIGH 금지 */
    if (!GPIO_Read()) {
        return;
    }

    /* 3) 오픈드레인 OFF -> push-pull */
    OWI_PORT_POM &= (uint8_t)~OWI_PIN_MASK;

    /* 4) 출력 HIGH */
    OWI_PORT_P  |= (uint8_t)OWI_PIN_MASK;
    OWI_PORT_PM &= (uint8_t)~OWI_PIN_MASK;

    delay_us(kick_us);

    /* 5) 다시 open-drain + release */
    OWI_PORT_POM |= (uint8_t)OWI_PIN_MASK;
    OWI_Release();
}

void GPIO_ForceHighKick(void)
{
    GPIO_StrongDriveHighKick(OWI_STRONG_DRIVE_HIGH_US);
}

static void OWI_DriveLow(void)
{
    OWI_PORT_POM |= (uint8_t)OWI_PIN_MASK;
    OWI_PORT_P   &= (uint8_t)~OWI_PIN_MASK;
    OWI_PORT_PM  &= (uint8_t)~OWI_PIN_MASK;
}

/* =========================================================
 * Diagnostics
 * ========================================================= */
uint8_t OWI_HasTimeout(void)
{
    return g_owi_timeout_latched;
}

void OWI_ClearTimeout(void)
{
    g_owi_timeout_latched = 0;
    g_owi_last_timeout_byte_index = 0xFFFFu;
    g_owi_last_timeout_bit_index  = 0xFFu;
}

uint16_t OWI_GetLastTimeoutByteIndex(void)
{
    return g_owi_last_timeout_byte_index;
}

uint8_t OWI_GetLastTimeoutBitIndex(void)
{
    return g_owi_last_timeout_bit_index;
}

/* =========================================================
 * OWI Init
 * ========================================================= */
void OWI_Init(uint32_t bit_time_us)
{
    bit_period_us = bit_time_us;
    (void)bit_period_us; /* 현재 타이밍은 매크로(TBIT) 사용 */

    OWI_PORT_POM |= (uint8_t)OWI_PIN_MASK;

    /* 외부 pull-up 사용 */
    OWI_PORT_PU &= (uint8_t)~OWI_PIN_MASK;

    OWI_ClearTimeout();

    /* idle = release */
    GPIO_Input();
}

/* =========================================================
 * Start/Stop/Secure
 * - 시퀀스는 유지
 * - strong만 선택적으로 사용
 * ========================================================= */
void OWI_Start(void)
{
    GPIO_Clear();
    delay_us(TSTART_HOLD);

    GPIO_Input();
    delay_us(TBIT);
}

void OWI_Stop(void)
{
    GPIO_Input();
    delay_us(TSTOP_LOW);
    delay_us(TIDLE);
}

static void OWI_StopWrite(void)
{
    OWI_Release();
    delay_us(TSTOP_LOW);
    delay_us(TIDLE);
}

static void OWI_StopRead(void)
{
    OWI_DriveLow();
    delay_us(TSTOP_LOW);
    OWI_Release();
    delay_us(TIDLE);
}

void OWI_SecureStop(void)
{
    int i;

    GPIO_Clear();
    delay_us(SECURE_HIGH);

    for (i = 0; i < (int)SECURE_TOGGLE_COUNT; i++) {

        /* HIGH 구간 */
        GPIO_Input();
        delay_us(SECURE_TOGGLE_HIGH);

        /* LOW 구간 */
        GPIO_Clear();
        delay_us(SECURE_TOGGLE_LOW);
    }

    /* 마지막 HIGH */
    GPIO_Input();
    delay_us(SECURE_HIGH);

    /* 이어서 기존 시퀀스 유지 */
    GPIO_Clear();
    delay_us(TSTART_HOLD);
    GPIO_Input();
}

/* =========================================================
 * Bit/Byte IO
 * - HIGH -> LOW 형식 유지
 * - strong만 선택적으로 사용
 * ========================================================= */
void OWI_WriteBit(int bit)
{
    uint32_t t_low  = bit ? (uint32_t)TLOW_1 : (uint32_t)TLOW_0;
    uint32_t t_high = (uint32_t)TBIT - t_low;

    /* HIGH 구간 */
    OWI_Release();
    delay_us(t_high);

    /* LOW 구간 */
    OWI_DriveLow();
    delay_us(t_low);
}

void OWI_WriteByte(uint8_t data)
{
    int i;
    for (i = 7; i >= 0; i--) {
        OWI_WriteBit((data >> i) & 0x01u);
    }
    GPIO_Input();
}

uint8_t OWI_ReadBit(void)
{
    uint8_t bit;
    int timeout = (int)(bit_period_us * 2u);

    while (!(GPIO_Read()) && timeout-- > 0) {
        delay_us(1u);
    }

    if (timeout <= 0) {
        if (!g_owi_timeout_latched) {
            // char msg[64];

            g_owi_timeout_latched = 1;
            g_owi_last_timeout_byte_index = g_owi_current_read_byte_index;
            g_owi_last_timeout_bit_index  = g_owi_current_read_bit_index;

            // sprintf(msg, "OWI Timeout B%u b%u\r\n",
            //         (unsigned)g_owi_last_timeout_byte_index,
            //         (unsigned)g_owi_last_timeout_bit_index);
            // HOST_PRINT(msg);
        }

        /* 기존 0xFF는 데이터를 오염시킴 */
        return 0u;
    }

    delay_us((bit_period_us * 1u) / 2u);
    bit = (uint8_t)GPIO_Read();
    delay_us((bit_period_us * 2u) / 5u);

    return (bit ? 1u : 0u);
}

uint8_t OWI_ReadByte(void)
{
    uint8_t data = 0;
    int i;

    for (i = 7; i >= 0; i--) {
        g_owi_current_read_bit_index = (uint8_t)(7 - i);
        data |= (uint8_t)(OWI_ReadBit() << i);
    }
    return data;
}

/* =========================================================
 * Debug Print
 * ========================================================= */
void OWI_T_ReadBytesAndPrint(int length)
{
    uint8_t buf[129];
    int i;
    char uart_buf[8];
    char tmp_buf[8];
    uint8_t va0, va1;

    if (length > 129) length = 129;
    if (length <= 0) return;

    OWI_ClearTimeout();

    for (i = 0; i < length; i++) {
        g_owi_current_read_byte_index = (uint16_t)i;
        buf[i] = OWI_ReadByte();
        if (OWI_HasTimeout()) break;
    }

    sprintf(uart_buf, "%02X ", buf[0]);
    strcpy(tmp_buf, uart_buf);
    HOST_PRINT(tmp_buf);

    for (i = 1; i < length; i += 2) {
        va0 = buf[i];
        va1 = (uint8_t)((i + 1 < length) ? buf[i + 1] : 0u);

        delay(10000);
        sprintf(uart_buf, "%02X%02X ", va0, va1);
        strcpy(tmp_buf, uart_buf);
        HOST_PRINT(tmp_buf);
        delay(10000);
    }
}

/* =========================================================
 * Command / Diagnostic
 * ========================================================= */
#define OWI_MAX_RETRY       2
#define OWI_RECOVERY_MIN_US 500

void OWI_A_CommandMode(const uint8_t *tx_data, uint8_t tx_len, uint8_t id)
{
    uint8_t CMD_LIST[6][4] = {
        {0x50,0x2E,0x00,0x00},
        {0x50,0x2E,0x01,0x00},
        {0x50,0x2E,0x02,0x00},
        {0x50,0x2E,0x16,0x00},
        {0x50,0x2E,0x41,0x00},
        {0x50,0x2E,0x00,0x00}
    };

    char line[128];
    size_t n = 0;
    uint8_t rx[RAM_BYTES];
    int i, j, retry, all_ff;
    uint8_t read_address = 0x51;

    delay_us(7000);

    for (j = 0; j < 6; j++) {
        OWI_SecureStop();
        for (i = 0; i < 4; i++) {
            OWI_WriteByte(CMD_LIST[j][i]);
        }
        OWI_Stop();

        delay_us(OWI_RECOVERY_MIN_US);

        for (i = 0; i < RAM_BYTES; i++) rx[i] = 0xFFu;

        for (retry = 0; retry <= OWI_MAX_RETRY; retry++) {
            delay_us(OWI_RECOVERY_MIN_US);

            OWI_ClearTimeout();
            OWI_SecureStop();
            OWI_WriteByte(read_address);

            for (i = 0; i < RAM_BYTES; i++) {
                g_owi_current_read_byte_index = (uint16_t)i;
                rx[i] = OWI_ReadByte();
                if (OWI_HasTimeout()) break;
            }

            OWI_Stop();

            all_ff = 1;
            for (i = 0; i < RAM_BYTES; i++) {
                if (rx[i] != 0xFFu) {
                    all_ff = 0;
                    break;
                }
            }

            if (!all_ff && !OWI_HasTimeout()) {
                break;
            }

            if (retry == OWI_MAX_RETRY) {
                return;
            }
        }

        n += sprintf(&line[n], "%02X%02X", rx[1], rx[2]);
        line[n++] = ',';
    }

    if (tx_data != NULL && tx_len == 3u) {
        for (retry = 0; retry <= OWI_MAX_RETRY; retry++) {

            OWI_ClearTimeout();
            OWI_SecureStop();
            OWI_WriteByte((uint8_t)(id << 1));

            for (i = 0; i < 3; i++) {
                OWI_WriteByte(tx_data[i]);
            }

            OWI_Stop();
            delay_us(OWI_RECOVERY_MIN_US);

            for (i = 0; i < RAM_BYTES; i++) rx[i] = 0xFFu;

            OWI_SecureStop();
            OWI_WriteByte((uint8_t)((id << 1) | 1u));

            for (i = 0; i < RAM_BYTES; i++) {
                g_owi_current_read_byte_index = (uint16_t)i;
                rx[i] = OWI_ReadByte();
                if (OWI_HasTimeout()) break;
            }

            OWI_Stop();

            all_ff = 1;
            for (i = 0; i < RAM_BYTES; i++) {
                if (rx[i] != 0xFFu) {
                    all_ff = 0;
                    break;
                }
            }

            if (!all_ff && !OWI_HasTimeout()) {
                break;
            }

            if (retry == OWI_MAX_RETRY) {
                return;
            }
        }

        n += sprintf(&line[n], "%02X%02X", rx[1], rx[2]);
    } else {
        n += sprintf(&line[n], "0000");
    }

    line[n++] = '\r';
    line[n++] = '\n';
    line[n] = '\0';

    HOST_PRINT(line);
    delay(10000);
}

void OWI_disable(void)
{
    HOST_PRINT("51\r\n");
}

void OWI_T_CommandMode(const uint8_t *tx_data, uint8_t tx_len, uint8_t id)
{
    int i;

    delay_us(10000);
    OWI_Init(OWI_BIT_PERIOD_US);

    OWI_SecureStop();
    OWI_WriteByte((uint8_t)(id << 1));

    for (i = 0; i < (int)tx_len; i++) {
        OWI_WriteByte(tx_data[i]);
    }

    OWI_Stop();
    HOST_PRINT("51\r\n");
}

void OWI_CommandMode(const uint8_t *tx_data, uint8_t tx_len, uint8_t id)
{
    int i;

    OWI_ClearTimeout();

    OWI_SecureStop();
    OWI_WriteByte((uint8_t)(id << 1));

    for (i = 0; i < (int)tx_len; i++) {
        OWI_WriteByte(tx_data[i]);
    }

    OWI_Stop();
    HOST_PRINT("51\r\n");
}

void OWI_ReadBytesAndPrint(int length, uint8_t id)
{
    static uint8_t buf[600];
    static char out[2 * 600 + 40];
    int i;
    uint16_t p = 0;

    if (length <= 0) {
        HOST_PRINT("Err:read_len_nonzero\r\n");
        return;
    }
    if (length > 600) length = 600;

    OWI_ClearTimeout();

    OWI_SecureStop();
    OWI_WriteByte((uint8_t)((id << 1) | 1u));

    for (i = 0; i < length; i++) {
        g_owi_current_read_byte_index = (uint16_t)i;
        buf[i] = OWI_ReadByte();
        if (OWI_HasTimeout()) break;
    }

    for (i = 0; i < length; i++) {
        uint8_t b = buf[i];
        out[p++] = "0123456789ABCDEF"[b >> 4];
        out[p++] = "0123456789ABCDEF"[b & 0x0F];
    }

    if (OWI_HasTimeout()) {
        p += (uint16_t)sprintf(&out[p], " !TO(B%u b%u)",
                               (unsigned)OWI_GetLastTimeoutByteIndex(),
                               (unsigned)OWI_GetLastTimeoutBitIndex());
    }

    out[p++] = '\r';
    out[p++] = '\n';
    out[p] = '\0';

    OWI_StopRead();
    HOST_PRINT(out);
}