#include "app_param_store.h"

#include <string.h>

#include "Com_debug.h"
#include "app_CiA402.h"
#include "Int_EEPROM24xx.h"
#include "crc.h"

/* 参数块格式：
 * 固定头(magic/version/len) + 业务参数 + CRC32
 * 用于上电校验，防止读取到脏数据。
 */
#define APP_PARAM_MAGIC 0x5250414DU /* "MPAR" */
#define APP_PARAM_VERSION 0x0001u
#define APP_PARAM_EEPROM_ADDR 0x0000u
#define APP_PARAM_AUTOSAVE_DEBOUNCE_MS 500u

/* Log level: 0=off, 1=error, 2=info */
#define APP_PARAM_STORE_LOG_LEVEL 2
#if APP_PARAM_STORE_LOG_LEVEL >= 2
#define APP_PS_LOGI(...) debug_printf(__VA_ARGS__)
#else
#define APP_PS_LOGI(...) ((void)0)
#endif
#if APP_PARAM_STORE_LOG_LEVEL >= 1
#define APP_PS_LOGE(...) debug_printf(__VA_ARGS__)
#else
#define APP_PS_LOGE(...) ((void)0)
#endif

typedef struct
{
    /* blob = 二进制数据块（Binary Large Object）：
     * 这里表示“整块写入/读出 EEPROM 的参数记录”。
     */
    uint32_t magic;
    uint16_t version;
    uint16_t payload_len;
    uint16_t acc_mm_s2;
    uint16_t dec_mm_s2;
    float step_loss_threshold_mm;
    uint32_t crc32;
} App_ParamBlob_t;

static uint32_t g_eeprom_i2c_last_err = 0u;
static App_RunParams_t g_last_seen_params = {0};
static uint8_t g_last_seen_valid = 0u;
static uint8_t g_autosave_dirty = 0u;
static uint32_t g_autosave_due_ms = 0u;

/* 使用STM32硬件CRC外设计算CRC32。 */
static uint32_t App_ParamStore_Crc32(const uint8_t *data, uint32_t len)
{
    uint32_t idx = 0u;
    uint32_t word = 0u;
    uint32_t crc = 0u;
    uint8_t first_word = 1u;

    if ((data == 0) || (len == 0u))
    {
        return 0u;
    }

    __HAL_CRC_DR_RESET(&hcrc);

    while (idx < len)
    {
        uint8_t b0 = data[idx++];
        uint8_t b1 = (idx < len) ? data[idx++] : 0u;
        uint8_t b2 = (idx < len) ? data[idx++] : 0u;
        uint8_t b3 = (idx < len) ? data[idx++] : 0u;

        word = ((uint32_t)b0) |
               ((uint32_t)b1 << 8) |
               ((uint32_t)b2 << 16) |
               ((uint32_t)b3 << 24);

        if (first_word != 0u)
        {
            crc = HAL_CRC_Calculate(&hcrc, &word, 1u);
            first_word = 0u;
        }
        else
        {
            crc = HAL_CRC_Accumulate(&hcrc, &word, 1u);
        }
    }
    
    return crc;

}

static bool App_ParamStore_Validate(const App_ParamBlob_t *blob)
{
    uint32_t calc_crc;

    /* 先做结构字段检查，再做CRC校验。 */
    if (blob->magic != APP_PARAM_MAGIC)
    {
        return false;
    }
    if (blob->version != APP_PARAM_VERSION)
    {
        return false;
    }
    if (blob->payload_len != (uint16_t)(sizeof(App_ParamBlob_t) - sizeof(uint32_t)))
    {
        return false;
    }
    if ((blob->acc_mm_s2 == 0u) || (blob->dec_mm_s2 == 0u))
    {
        return false;
    }
    if ((blob->step_loss_threshold_mm <= 0.0f) || (blob->step_loss_threshold_mm > SOFT_LIMIT_MAX_MM))
    {
        return false;
    }

    calc_crc = App_ParamStore_Crc32((const uint8_t *)blob, (uint32_t)(sizeof(App_ParamBlob_t) - sizeof(uint32_t)));
    return (calc_crc == blob->crc32);
}

static uint32_t App_ParamStore_CalcBlobCrc(const App_ParamBlob_t *blob)
{
    return App_ParamStore_Crc32((const uint8_t *)blob, (uint32_t)(sizeof(App_ParamBlob_t) - sizeof(uint32_t)));
}

static void App_ParamStore_ApplyThresholdToOD(float threshold_mm)
{
    /* 将丢步阈值同步到OD，CANopen运行时需加锁访问。 */
    OD_entry_t *entry = OD_find(OD, CIA402_INDEX_FOLLOWING_ERROR_WINDOW);
    if (entry == 0)
    {
        return;
    }

    if (CO != 0)
    {
        CO_LOCK_OD(CO->CANmodule);
        (void)OD_set_f32(entry, 0, threshold_mm, true);
        CO_UNLOCK_OD(CO->CANmodule);
    }
    else
    {
        (void)OD_set_f32(entry, 0, threshold_mm, true);
    }
}

static void App_ParamStore_ApplyAccDecToOD(uint16_t acc_mm_s2, uint16_t dec_mm_s2)
{
    /* 将加减速度同步到OD，保持网关与本地参数一致。 */
    OD_entry_t *entry_acc = OD_find(OD, CIA402_INDEX_PROFILE_ACC);
    OD_entry_t *entry_dec = OD_find(OD, CIA402_INDEX_PROFILE_DEC);
    if ((entry_acc == 0) || (entry_dec == 0))
    {
        return;
    }

    if (CO != 0)
    {
        CO_LOCK_OD(CO->CANmodule);
        (void)OD_set_u32(entry_acc, 0, (uint32_t)acc_mm_s2, true);
        (void)OD_set_u32(entry_dec, 0, (uint32_t)dec_mm_s2, true);
        CO_UNLOCK_OD(CO->CANmodule);
    }
    else
    {
        (void)OD_set_u32(entry_acc, 0, (uint32_t)acc_mm_s2, true);
        (void)OD_set_u32(entry_dec, 0, (uint32_t)dec_mm_s2, true);
    }
}

static bool App_ParamStore_ReadCurrentFromOD(App_RunParams_t *params)
{
    OD_entry_t *entry_acc = OD_find(OD, CIA402_INDEX_PROFILE_ACC);
    OD_entry_t *entry_dec = OD_find(OD, CIA402_INDEX_PROFILE_DEC);
    OD_entry_t *entry_ferr = OD_find(OD, CIA402_INDEX_FOLLOWING_ERROR_WINDOW);
    uint32_t acc_raw = 0u;
    uint32_t dec_raw = 0u;
    float32_t ferr_raw = 0.0f;

    if ((params == 0) || (entry_acc == 0) || (entry_dec == 0) || (entry_ferr == 0))
    {
        return false;
    }

    if (CO != 0)
    {
        CO_LOCK_OD(CO->CANmodule);
        (void)OD_get_u32(entry_acc, 0, &acc_raw, true);
        (void)OD_get_u32(entry_dec, 0, &dec_raw, true);
        (void)OD_get_f32(entry_ferr, 0, &ferr_raw, true);
        CO_UNLOCK_OD(CO->CANmodule);
    }
    else
    {
        (void)OD_get_u32(entry_acc, 0, &acc_raw, true);
        (void)OD_get_u32(entry_dec, 0, &dec_raw, true);
        (void)OD_get_f32(entry_ferr, 0, &ferr_raw, true);
    }

    if ((acc_raw == 0u) || (acc_raw > 65535u) || (dec_raw == 0u) || (dec_raw > 65535u))
    {
        return false;
    }
    if (((float)ferr_raw <= 0.0f) || ((float)ferr_raw > SOFT_LIMIT_MAX_MM))
    {
        return false;
    }

    params->acc_mm_s2 = (uint16_t)acc_raw;
    params->dec_mm_s2 = (uint16_t)dec_raw;
    params->step_loss_threshold_mm = (float)ferr_raw;
    return true;
}

static uint8_t App_ParamStore_ParamsEqual(const App_RunParams_t *a, const App_RunParams_t *b)
{
    float diff;

    if ((a == 0) || (b == 0))
    {
        return 0u;
    }

    if ((a->acc_mm_s2 != b->acc_mm_s2) || (a->dec_mm_s2 != b->dec_mm_s2))
    {
        return 0u;
    }

    diff = a->step_loss_threshold_mm - b->step_loss_threshold_mm;
    if (diff < 0.0f)
    {
        diff = -diff;
    }
    return (diff <= 0.0001f) ? 1u : 0u;
}

void App_ParamStore_Init(void)
{
    /* EEPROM驱动初始化：参数由Int_EEPROM24xx内部宏配置。 */
    if (Int_EEPROM24xx_Init() != INT_EEPROM_OK)
    {
        g_eeprom_i2c_last_err = Int_EEPROM24xx_GetLastHalError();
        APP_PS_LOGE("[EEPROM] init failed");
    }

    g_last_seen_valid = 0u;
    g_autosave_dirty = 0u;
    g_autosave_due_ms = 0u;
}

bool App_ParamStore_Read(App_RunParams_t *params)
{
    App_ParamBlob_t blob;
    uint32_t calc_crc;

    if (params == 0)
    {
        return false;
    }

    /* 从固定地址读出完整参数块并校验。 */
    if (Int_EEPROM24xx_Read(APP_PARAM_EEPROM_ADDR, (uint8_t *)&blob, (uint16_t)sizeof(blob)) != INT_EEPROM_OK)
    {
        g_eeprom_i2c_last_err = Int_EEPROM24xx_GetLastHalError();
        APP_PS_LOGE("[EEPROM] read failed, i2c_err=0x%08lX", (unsigned long)g_eeprom_i2c_last_err);
        return false;
    }

    if (!App_ParamStore_Validate(&blob))
    {
        calc_crc = App_ParamStore_CalcBlobCrc(&blob);
        APP_PS_LOGI("[EEPROM] invalid blob: magic=0x%08lX ver=%u len=%u acc=%u dec=%u ferr=%.4f crc=0x%08lX calc=0x%08lX",
                    (unsigned long)blob.magic,
                    (unsigned int)blob.version,
                    (unsigned int)blob.payload_len,
                    (unsigned int)blob.acc_mm_s2,
                    (unsigned int)blob.dec_mm_s2,
                    (double)blob.step_loss_threshold_mm,
                    (unsigned long)blob.crc32,
                    (unsigned long)calc_crc);
        return false;
    }

    params->acc_mm_s2 = blob.acc_mm_s2;
    params->dec_mm_s2 = blob.dec_mm_s2;
    params->step_loss_threshold_mm = blob.step_loss_threshold_mm;
    return true;
}

bool App_ParamStore_LoadAndApply(void)
{
    App_RunParams_t p;

    /* 上电读取成功后，应用到运行参数与OD对象。 */
    if (!App_ParamStore_Read(&p))
    {
        APP_PS_LOGI("[EEPROM] no valid params in EEPROM, keep defaults");
        return false;
    }

    stepper_1.acc = p.acc_mm_s2;
    stepper_1.dec = p.dec_mm_s2;
    App_ParamStore_ApplyAccDecToOD(p.acc_mm_s2, p.dec_mm_s2);
    App_ParamStore_ApplyThresholdToOD(p.step_loss_threshold_mm);

    APP_PS_LOGI("[EEPROM] loaded acc=%u dec=%u ferr=%.4f",
                (unsigned int)p.acc_mm_s2,
                (unsigned int)p.dec_mm_s2,
                (double)p.step_loss_threshold_mm);
    g_last_seen_params = p;
    g_last_seen_valid = 1u;
    g_autosave_dirty = 0u;
    return true;
}

bool App_ParamStore_Save(const App_RunParams_t *params)
{
    App_ParamBlob_t blob;

    /* 写入前先做业务范围检查。 */
    if (params == 0)
    {
        return false;
    }
    if ((params->acc_mm_s2 == 0u) || (params->dec_mm_s2 == 0u))
    {
        return false;
    }
    if ((params->step_loss_threshold_mm <= 0.0f) || (params->step_loss_threshold_mm > SOFT_LIMIT_MAX_MM))
    {
        return false;
    }

    memset(&blob, 0, sizeof(blob));
    blob.magic = APP_PARAM_MAGIC;
    blob.version = APP_PARAM_VERSION;
    blob.payload_len = (uint16_t)(sizeof(App_ParamBlob_t) - sizeof(uint32_t));
    blob.acc_mm_s2 = params->acc_mm_s2;
    blob.dec_mm_s2 = params->dec_mm_s2;
    blob.step_loss_threshold_mm = params->step_loss_threshold_mm;
    blob.crc32 = App_ParamStore_Crc32((const uint8_t *)&blob, (uint32_t)(sizeof(App_ParamBlob_t) - sizeof(uint32_t)));

    /* 写入固定地址，供下次上电加载。 */
    if (Int_EEPROM24xx_Write(APP_PARAM_EEPROM_ADDR, (const uint8_t *)&blob, (uint16_t)sizeof(blob)) != INT_EEPROM_OK)
    {
        g_eeprom_i2c_last_err = Int_EEPROM24xx_GetLastHalError();
        APP_PS_LOGE("[EEPROM] save failed, i2c_err=0x%08lX", (unsigned long)g_eeprom_i2c_last_err);
        return false;
    }

    APP_PS_LOGI("[EEPROM] saved acc=%u dec=%u ferr=%.4f",
                (unsigned int)params->acc_mm_s2,
                (unsigned int)params->dec_mm_s2,
                (double)params->step_loss_threshold_mm);
    return true;
}

void App_ParamStore_Process(void)
{
    App_RunParams_t current;
    uint32_t now_ms;

    if (!App_ParamStore_ReadCurrentFromOD(&current))
    {
        return;
    }

    now_ms = HAL_GetTick();

    if (g_last_seen_valid == 0u)
    {
        g_last_seen_params = current;
        g_last_seen_valid = 1u;
        return;
    }

    if (App_ParamStore_ParamsEqual(&current, &g_last_seen_params) == 0u)
    {
        g_last_seen_params = current;
        g_autosave_dirty = 1u;
        g_autosave_due_ms = now_ms + APP_PARAM_AUTOSAVE_DEBOUNCE_MS;
        return;
    }

    if (g_autosave_dirty == 0u)
    {
        return;
    }

    if ((int32_t)(now_ms - g_autosave_due_ms) < 0)
    {
        return;
    }

    if (App_ParamStore_Save(&g_last_seen_params))
    {
        g_autosave_dirty = 0u;
    }
}