/**
 * app_charge_task.c — AI-4 充电管理任务（µC/OS-III）
 *
 * 集成充电状态机 + BQ25756 I2C 驱动
 *
 * 任务结构：
 *   ChargeTask (prio 5):
 *     每 200ms: 读 BQ25756 ADC → 输入状态机 → 执行 BQ25756 寄存器操作
 *     每 10s: 复位 BQ25756 看门狗
 *
 *   AdcTask (prio 4):
 *     采集 NTC ADC → 转换为温度值 → 全局变量供 ChargeTask 读取
 */

#include "board_config.h"
#include "bq25756_regs.h"
#include "bq_i2c_opt.h"
#include "bq_verified_ops.h"
#include "charge_sm.h"
#include <stdio.h>

/*===========================================================================
 * 全局变量
 *===========================================================================*/

static int32_t g_vbat_mv = 0;    /* 电池电压 mV */
static int32_t g_ibat_ma = 0;    /* 充电电流 mA */
static int8_t  g_temp_c  = 25;   /* NTC 温度 °C（默认 25 表示无读数）*/

/*===========================================================================
 * NTC 温度计算（103AT, 10kΩ, β=3435K）
 *===========================================================================*/

/**
 * @brief 从 NTC ADC 原始值计算温度
 * @param  adc_val: 12-bit ADC 值 (0~4095)
 * @return 温度 °C
 */
static int8_t ntc_adc_to_temp(uint16_t adc_val)
{
    /* 分压公式：V_ntc = Vref × R_ntc / (R_ntc + R_pullup)
     *          ADC = 4095 × R_ntc / (R_ntc + 10000)
     * 反推：   R_ntc = 10000 × ADC / (4095 - ADC)
     *
     * 简化：查表或近似公式
     * 103AT β=3435K, R25=10kΩ
     * T = 1 / (1/298.15 + ln(R_ntc/10000)/3435) - 273.15
     */

    if (adc_val >= 4090) return -40;  /* 开路 */
    if (adc_val <= 5)    return 125;  /* 短路 */

    float r_ntc = (float)(10000UL * adc_val) / (4095.0f - (float)adc_val);
    float temp_k = 1.0f / (1.0f/298.15f + logf(r_ntc/10000.0f)/3435.0f);
    float temp_c = temp_k - 273.15f;

    return (int8_t)(temp_c + 0.5f);  /* 四舍五入 */
}

/*===========================================================================
 * 充电管理任务（优先级 5）
 *===========================================================================*/

static void ChargeTask(void *p_arg)
{
    ChargeSM sm;
    ChargeSM_InitDefault(&sm);  /* AI-4: 7S/2A/NTC/50°C/0°C */

    OS_ERR   err;
    uint32_t wd_timer = 0;

    while (1) {
        /* --- 采集数据 --- */
        g_vbat_mv = BQ25756_ReadVBAT_mV();
        g_ibat_ma = BQ25756_ReadIBAT_mA();
        /* g_temp_c 由 AdcTask 更新 */

        /* --- 输入状态机 --- */
        ChargeSM_Decision d = ChargeSM_Run(&sm, g_vbat_mv, g_ibat_ma, g_temp_c);

        /* --- 执行决策 --- */
        switch (d.action) {
        case SM_ACTION_SET_PRECHG:
            BQ25756_WritePrechargeCurrent(d.target_current_ma);
            BQ25756_SetEN_CHG(1);
            BQ_CE_LOW();
            break;

        case SM_ACTION_SET_CC:
            BQ25756_WriteChargeCurrent(d.target_current_ma);
            BQ25756_SetEN_CHG(1);
            BQ_CE_LOW();
            break;

        case SM_ACTION_STOP:
            BQ25756_SetEN_CHG(0);
            BQ_CE_HIGH();
            break;

        case SM_ACTION_RESTART:
            BQ25756_WriteChargeCurrent(d.target_current_ma);
            BQ25756_SetEN_CHG(1);
            BQ_CE_LOW();
            break;

        case SM_ACTION_NONE:
        default:
            break;
        }

        /* --- 看门狗复位（每 10s）--- */
        wd_timer += CHARGE_TASK_PERIOD_MS;
        if (wd_timer >= WD_RESET_PERIOD_MS) {
            BQ25756_ResetWD();
            wd_timer = 0;
        }

        /* --- 调试输出 --- */
        if (d.action != SM_ACTION_NONE) {
            printf("[CHG] %s | VBAT=%ldmV IBAT=%ldmA TEMP=%dC | %s",
                   ChargeSM_StateStr(sm.state),
                   (long)g_vbat_mv, (long)g_ibat_ma,
                   (int)g_temp_c, d.reason);
        }

        /* 休眠 200ms */
        OSTimeDlyHMSM(0, 0, 0, CHARGE_TASK_PERIOD_MS,
                      OS_OPT_TIME_DLY, &err);
    }
}

/*===========================================================================
 * ADC 采样任务（优先级 4，比充电任务高一级）
 *===========================================================================*/

static OS_TCB  AdcTaskTCB;
static CPU_STK AdcTaskStk[ADC_TASK_STACK_SIZE];

/* NTC ADC 配置 */
static void ntc_adc_init(void)
{
    /* GD32F303 ADC0 + GPIO PA3 */
    rcu_periph_clock_enable(RCU_GPIOA);
    rcu_periph_clock_enable(RCU_ADC0);

    gpio_init(NTC_ADC_PORT, GPIO_MODE_AIN, GPIO_OSPEED_2MHZ, NTC_ADC_PIN);

    adc_deinit(NTC_ADC_PERIPH);
    adc_channel_length_config(NTC_ADC_PERIPH, ADC_REGULAR_CHANNEL, 1);
    adc_regular_channel_config(NTC_ADC_PERIPH, 0, NTC_ADC_CHANNEL,
                               ADC_SAMPLETIME_239POINT5);
    adc_external_trigger_source_config(NTC_ADC_PERIPH, ADC_REGULAR_CHANNEL,
                                        ADC_EXTTRIG_REGULAR_NONE);
    adc_data_alignment_config(NTC_ADC_PERIPH, ADC_DATAALIGN_RIGHT);
    adc_resolution_config(NTC_ADC_PERIPH, ADC_RESOLUTION_12B);
    adc_enable(NTC_ADC_PERIPH);
    adc_calibration_enable(NTC_ADC_PERIPH);
}

static void AdcTask(void *p_arg)
{
    OS_ERR err;

    ntc_adc_init();

    while (1) {
        /* 读 NTC ADC */
        adc_software_trigger_enable(NTC_ADC_PERIPH, ADC_REGULAR_CHANNEL);
        while (!adc_flag_get(NTC_ADC_PERIPH, ADC_FLAG_EOC));
        uint16_t adc_val = adc_regular_data_read(NTC_ADC_PERIPH);

        g_temp_c = ntc_adc_to_temp(adc_val);

        /* 每 500ms 采样一次 */
        OSTimeDlyHMSM(0, 0, 0, 500, OS_OPT_TIME_DLY, &err);
    }
}

/*===========================================================================
 * 系统初始化入口
 *===========================================================================*/

void App_Charge_Init(void)
{
    OS_ERR err;

    /* --- 硬件初始化 --- */
    /* I2C */
    I2C_Bus bus = {
        .instance = BQ_I2C_PERIPH,
        .scl_port = BQ_I2C_SCL_PORT,
        .scl_pin  = BQ_I2C_SCL_PIN,
        .sda_port = BQ_I2C_SDA_PORT,
        .sda_pin  = BQ_I2C_SDA_PIN,
        .speed    = BQ_I2C_SPEED,
    };
    BQ_I2C_Init(&bus);

    /* CE 引脚 */
    rcu_periph_clock_enable(RCU_GPIOA);
    gpio_init(BQ_CE_PORT, GPIO_MODE_OUT_PP, GPIO_OSPEED_2MHZ, BQ_CE_PIN);
    BQ_CE_HIGH();  /* 初始拉高，禁止充电 */

    /* PG 引脚（可选） */
    gpio_init(BQ_PG_PORT, GPIO_MODE_IN_FLOATING, GPIO_OSPEED_2MHZ, BQ_PG_PIN);

    /* --- BQ25756 初始化 --- */
    int ret = BQ25756_AI4_Init();
    if (ret != 0) {
        printf("[ERROR] BQ25756 init failed, step %d", ret);
        return;
    }
    printf("[OK] BQ25756 AI-4 init complete");

    /* --- 创建任务 --- */
    OSTaskCreate((OS_TCB      *)&ChargeTaskTCB,
                 (CPU_CHAR    *)"Charge",
                 (OS_TASK_PTR  )ChargeTask,
                 (void        *)0,
                 (OS_PRIO      )CHARGE_TASK_PRIO,
                 (CPU_STK     *)ChargeTaskStk,
                 (CPU_STK_SIZE )CHARGE_TASK_STACK_SIZE / 10,
                 (CPU_STK_SIZE )CHARGE_TASK_STACK_SIZE,
                 (OS_MSG_QTY   )0,
                 (OS_TICK      )0,
                 (void        *)0,
                 (OS_OPT       )(OS_OPT_TASK_STK_CHK | OS_OPT_TASK_STK_CLR),
                 (OS_ERR      *)&err);

    OSTaskCreate((OS_TCB      *)&AdcTaskTCB,
                 (CPU_CHAR    *)"ADC",
                 (OS_TASK_PTR  )AdcTask,
                 (void        *)0,
                 (OS_PRIO      )ADC_TASK_PRIO,
                 (CPU_STK     *)AdcTaskStk,
                 (CPU_STK_SIZE )ADC_TASK_STACK_SIZE / 10,
                 (CPU_STK_SIZE )ADC_TASK_STACK_SIZE,
                 (OS_MSG_QTY   )0,
                 (OS_TICK      )0,
                 (void        *)0,
                 (OS_OPT       )(OS_OPT_TASK_STK_CHK | OS_OPT_TASK_STK_CLR),
                 (OS_ERR      *)&err);

    printf("[OK] Charge + ADC tasks created");
}