/*
 * test_power_on_stable.c — 上电自检: 基准值稳定后才结束自检 (V4.23)
 *
 * 背景: 原逻辑 _stable_cnt 达 128 样本(≈1.3s)即判稳, 与"基准值是否真稳定"无关;
 *       且 static 计数不清零, 二次稳定期(安全复位)1 个样本即判稳(绿灯自检形同虚设)。
 * 修复: 稳定期累计样本 g_stable_cnt + 连续窗口 Origin 均值漂移 ≤0.1% 的
 *       g_settle_cnt; 两者达标才 g_loop_stable=1; 硬兜底 500 样本(5s)。
 *
 * 验证:
 *   1. 干净常量值 → 第 200 样本判稳 (窗口100/200 两次漂移 0)
 *   2. 首窗 Origin 尖峰(1.3×) → 多等一窗, 第 300 样本判稳
 *   3. 持续漂移(每窗 +500, >0.1% 带) → 永不 settle, 第 500 样本硬兜底判稳
 *   4. 判稳退出后计数清零, 二次稳定期重新从 0 累计(不瞬间判稳)
 *
 * 编译: gcc -Wall -o test_power_on_stable test_power_on_stable.c && ./test_power_on_stable
 *===========================================================================*/
#include <stdio.h>
#include <stdint.h>
#include <assert.h>

#define WIN                100     /* 稳定期小窗口 */
#define STABLE_SAMPLES     128     /* 稳定期最少样本数 */
#define STABLE_ORIGIN_PPT  1       /* 0.1% */
#define STABLE_SETTLE_WINDOWS 2
#define STABLE_MAX_SAMPLES 500

static uint32_t origin;
static uint32_t g_origin_prev;
static uint16_t g_stable_cnt;
static uint16_t g_settle_cnt;
static uint8_t  g_loop_stable;

/* 仿真 vd1_task 稳定期单样本处理; 返回 1=本样本判稳 */
static int stable_step(uint32_t value)
{
    static uint32_t sum = 0;
    static uint16_t cnt = 0;
    uint32_t prev_origin;
    int win_done = 0;

    if (g_loop_stable) return 1;
    if (origin == 0)   return 0;

    prev_origin = origin;
    sum += value; cnt++;
    g_stable_cnt++;
    if (cnt >= WIN) {
        win_done = 1;
        origin = sum / WIN;
        sum = 0; cnt = 0;
    }
    if (win_done) {
        uint32_t drift = (origin > prev_origin) ? (origin - prev_origin)
                                                : (prev_origin - origin);
        uint32_t band  = (uint32_t)(origin * STABLE_ORIGIN_PPT / 1000);
        if (drift <= band) {
            if (g_settle_cnt < 0xFFFF) g_settle_cnt++;
        } else {
            g_settle_cnt = 0;
        }
    }

    if ((g_stable_cnt >= STABLE_SAMPLES &&
         g_settle_cnt >= STABLE_SETTLE_WINDOWS) ||
        g_stable_cnt >= STABLE_MAX_SAMPLES) {
        g_loop_stable = 1;
        g_stable_cnt  = 0;
        g_settle_cnt  = 0;
        return 1;
    }
    return 0;
}

static void reset(uint32_t initial_origin)
{
    origin         = initial_origin;
    g_origin_prev  = 0;
    g_stable_cnt   = 0;
    g_settle_cnt   = 0;
    g_loop_stable  = 0;
}

int main(void)
{
    const uint32_t BASE = 128844UL;
    int i, done;

    /* --- 1. 干净常量值: 第 200 样本判稳 --- */
    reset(BASE);
    done = 0;
    for (i = 1; i <= 600 && !done; i++) {
        done = stable_step(BASE);
        if (done) break;
    }
    printf("1. 常量值 判稳样本=%d (期望 200)\n", i);
    assert(i == 200);
    assert(g_stable_cnt == 0 && g_settle_cnt == 0);

    /* --- 2. 首窗 Origin 尖峰(1.3×, 实际值正常): 第 300 样本判稳 --- */
    reset((uint32_t)(BASE * 1.3));
    done = 0;
    for (i = 1; i <= 600 && !done; i++) {
        done = stable_step(BASE);
        if (done) break;
    }
    printf("2. 首窗尖峰  判稳样本=%d (期望 300)\n", i);
    assert(i == 300);

    /* --- 3. 持续漂移: 每窗均值 +500 (>0.1% 带) → 硬兜底 500 --- */
    reset(BASE);
    done = 0;
    for (i = 1; i <= 600 && !done; i++) {
        uint32_t w = (uint32_t)((i - 1) / WIN);
        done = stable_step(BASE + 500UL * w);
        if (done) break;
    }
    printf("3. 持续漂移  判稳样本=%d (期望 500 硬兜底)\n", i);
    assert(i == 500);

    /* --- 4. 二次稳定期: 计数清零, 重新累计 → 第 200 样本判稳(非 1 样本) --- */
    reset(BASE);
    done = 0;
    for (i = 1; i <= 600 && !done; i++) {
        done = stable_step(BASE);
        if (done) break;
    }
    assert(i == 200);                     /* 第一次完成 */
    /* 模拟安全复位: 仅清 g_loop_stable, 计数应已是 0 */
    g_loop_stable = 0;
    done = 0;
    for (i = 1; i <= 600 && !done; i++) {
        done = stable_step(BASE);
        if (done) break;
    }
    printf("4. 二次稳定期 判稳样本=%d (期望 200, 修掉原 1 样本瞬间判稳)\n", i);
    assert(i == 200);

    printf("ALL PASS (test_power_on_stable)\n");
    return 0;
}