/* mp_power.c — 功耗管理域：meow_powermgr IPC（/api/power*,policy,window,events）。 */
#include "mp.h"


int ipc_pm_query(uint32_t subset, char *out, int cap)
{
    int fd = ipc_connect_tmo(g_sock_pm, IPC_TIMEOUT_MS);
    if (fd < 0) return MEOW_ERR_NODEV;
    int rc = MEOW_ERR_INTERNAL;
    if (ipc_hello(fd) < 0) { rc = MEOW_ERR_INTERNAL; goto done; }
    m_pm_query_t q;
    memset(&q, 0, sizeof q);
    q.subset = subset;
    if (send_frame(fd, MSG_PM_QUERY, 0x31, &q, sizeof q) < 0) { rc = MEOW_ERR_IO; goto done; }
    uint8_t buf[MEOW_IPC_MAX];
    uint16_t type; uint32_t rid;
    int n = recv_frame(fd, &type, &rid, buf, sizeof buf);
    if (n < 12) { rc = MEOW_ERR_IO; goto done; }                    /* code(4)+subset(4)+json_len(2)+pad(2) */
    if (type != MSG_PM_RESULT) { rc = MEOW_ERR_INVAL; goto done; }
    uint32_t c; memcpy(&c, buf, 4);
    if (c != MEOW_OK) { rc = (int)c; goto done; }
    /* powermgr 发**紧凑**负载：json 从偏移 12 起（json_len 在偏移 8）；同 m_pm_result_t 布局，兼容全量/紧凑。 */
    uint16_t jl; memcpy(&jl, buf + 8, 2);
    if (jl > MEOW_IPC_MAX - 12) jl = (uint16_t)(MEOW_IPC_MAX - 12);
    if ((size_t)jl >= (size_t)cap) jl = (uint16_t)(cap - 1);
    memcpy(out, buf + 12, jl);
    out[jl] = 0;
    rc = MEOW_OK;
done:
    close(fd);
    return rc;
}

int api_power(int sock)
{
    char js[MEOW_IPC_MAX];
    int rc = ipc_pm_query(0, js, sizeof js);
    if (rc != MEOW_OK || !utf8_valid_n(js, strlen(js)))   /* 上游坏字节 → 不返回，降级 */
        return send_err(sock, 503, "POWER_UNAVAILABLE", "电源管理服务不可用");
    return send_json(sock, 200, js);
}

int ipc_pm_send(uint16_t req_type, const void *pl, uint32_t plen,
                       uint16_t *rtype, char *out, int cap)
{
    int fd = ipc_connect_tmo(g_sock_pm, IPC_TIMEOUT_MS);
    if (fd < 0) return MEOW_ERR_NODEV;
    int rc = MEOW_ERR_INTERNAL;
    if (rtype) *rtype = 0;
    if (ipc_hello(fd) < 0) { rc = MEOW_ERR_INTERNAL; goto done; }
    if (send_frame(fd, req_type, 0x41, pl, plen) < 0) { rc = MEOW_ERR_IO; goto done; }
    uint8_t buf[MEOW_IPC_MAX];
    uint16_t type; uint32_t rid;
    int n = recv_frame(fd, &type, &rid, buf, sizeof buf);
    if (n <= 0) { rc = MEOW_ERR_IO; goto done; }
    if (rtype) *rtype = type;
    if (type == MSG_ERR) {
        m_err_t e; memcpy(&e, buf, sizeof e);
        rc = (int)e.code; goto done;
    }
    if (n < 12) { rc = MEOW_ERR_IO; goto done; }              /* code(4)+subset(4)+json_len(2)+pad(2) */
    uint32_t c; memcpy(&c, buf, 4);
    if (c != MEOW_OK) { rc = (int)c; goto done; }
    uint16_t jl; memcpy(&jl, buf + 8, 2);
    if (jl > MEOW_IPC_MAX - 12) jl = (uint16_t)(MEOW_IPC_MAX - 12);
    if ((size_t)jl >= (size_t)cap) jl = (uint16_t)(cap - 1);
    memcpy(out, buf + 12, jl); out[jl] = 0;
    rc = (int)jl;
done:
    close(fd);
    return rc;
}

/* 在对象 JSON（已剥尾部 `}`、经 utf8 校验）上拼 guard③ `policy_write_enabled` 顶层键：
 * 拼完 jv_parse 自校验，绝不发非法 JSON（防 overview 教训）；失败返回 -1（调用方回 500，绝不带病下发）。 */
int power_policy_append_flag(sbuf_t *out, const char *obj)
{
    sA(out, "%s", obj);
    sA(out, ",\"policy_write_enabled\":%s}", panel_policy_write_enabled() ? "true" : "false");
    jv_t *chk = jv_parse(out->b ? out->b : "{}", (int)(out->b ? out->n : 2));
    if (!chk) return -1;
    jv_free(chk);
    return 0;
}

int api_power_policy_get(int sock)
{
    char js[MEOW_IPC_MAX];
    uint16_t rt = 0;
    int rc = ipc_pm_send(MSG_PM_POLICY_GET, NULL, 0, &rt, js, sizeof js);
    if (rc <= 0)
        return send_err(sock, 503, "POWER_UNAVAILABLE", "电源管理服务不可用（powermgr 未运行/IPC 不可达）");
    if (rt != MSG_PM_RESULT || !utf8_valid_n(js, strlen(js)))
        return send_err(sock, 503, "POWER_UNAVAILABLE", "电源管理服务应答包含非法字节");
    /* 追加顶层 `policy_write_enabled`（面板侧 gate 状态，独立于 powermgr 的 `enacted`）：
     * 稳妥剥外层括号再拼（同 net_block_fill 手法）。上游非对象（数组/文本）时原样透传、不带该键
     * （前端缺省视为已开启，兼容旧 powermgr）。 */
    size_t l = strlen(js);
    while (l && (js[l - 1] == ' ' || js[l - 1] == '\t' || js[l - 1] == '\n' || js[l - 1] == '\r')) js[--l] = 0;
    if (l < 2 || js[0] != '{' || js[l - 1] != '}') return send_json(sock, 200, js);
    js[l - 1] = 0;   /* 去尾部 } */
    sbuf_t s = {0};
    if (power_policy_append_flag(&s, js) != 0) { sbuf_free(&s); return send_err(sock, 500, "INTERNAL", "电源策略聚合输出未通过 JSON 自校验"); }
    int out = send_json(sock, 200, s.b ? s.b : "{}");
    sbuf_free(&s);
    return out;
}

int api_power_policy_set(int sock, const char *body, size_t body_len)
{
    if (!body || !body[0]) return send_err(sock, 400, "BAD_REQUEST", "缺少 body");
    /* guard③ policy 默认关：写端点默认关闭，须在设置开启 panel.policy_enabled 才放行（只读 GET 不受此限）。
     * 注意：powermgr 侧另有 `enacted`（策略是否已应用），本 gate 是面板侧写入口门禁，二者独立。 */
    if (!panel_policy_write_enabled())
        return send_err(sock, 403, "POLICY_DISABLED", "电源策略写默认关闭：先到面板设置开启 panel.policy_enabled（危险操作）");
    jv_t *root = jv_parse(body, (int)body_len);
    if (!root) return send_err(sock, 400, "BAD_REQUEST", "body 非合法 JSON");
    jv_t *ji = jv_obj_get(root, "item"), *jv = jv_obj_get(root, "value");
    char item[20] = "", val[40] = "";
    if (ji && ji->type == J_STR && ji->str) snprintf(item, sizeof item, "%s", ji->str);
    if (jv && jv->type == J_STR && jv->str) snprintf(val, sizeof val, "%s", jv->str);
    else if (jv && jv->type == J_NUM) snprintf(val, sizeof val, "%lld", jv->inum);
    jv_free(root);
    if (!item[0]) return send_err(sock, 422, "UNSUPPORTED", "缺 item（profile/low-pct/crit-pct/bri-cap/scr-cap）");
    if (!val[0]) return send_err(sock, 422, "UNSUPPORTED", "缺 value");

    m_pm_policy_set_t s; memset(&s, 0, sizeof s);
    snprintf(s.item, sizeof s.item, "%.15s", item);   /* item[16] 留一个 NUL；防越界截断告警 */
    snprintf(s.val, sizeof s.val, "%.31s", val);      /* val[32] 同理 */
    char js[MEOW_IPC_MAX];
    uint16_t rt = 0;
    int rc = ipc_pm_send(MSG_PM_POLICY_SET, &s, sizeof s, &rt, js, sizeof js);
    if (rc <= 0) {
        if (rt == MSG_ERR)   /* 权限不足：powermgr 拒绝（面板 root 仅当被白名单才放行；如实回传） */
            return send_err(sock, 403, "FORBIDDEN", rc == MEOW_ERR_PERM ? "设备身份不允许写电源策略" : "电源策略写入被拒绝");
        return send_err(sock, 503, "POWER_UNAVAILABLE", "电源管理服务不可用（powermgr 未运行/IPC 不可达）");
    }
    if (rt != MSG_PM_RESULT || !utf8_valid_n(js, strlen(js)))
        return send_err(sock, 503, "POWER_UNAVAILABLE", "电源管理服务应答包含非法字节");
    /* 服务端对非法值回 ok:false（HTTP 层 200，code 仍 OK）；按其 why 映射 422。 */
    if (strstr(js, "\"ok\":false")) {
        char why[96] = "";
        jv_t *jr = jv_parse(js, (int)strlen(js));
        if (jr) { jv_t *w = jv_obj_get(jr, "why"); if (w && w->type == J_STR && w->str) snprintf(why, sizeof why, "%s", w->str); jv_free(jr); }
        return send_err(sock, 422, "UNSUPPORTED", why[0] ? why : "非法电源策略值");
    }
    return send_json(sock, 200, js);
}

int api_power_window(int sock, uint16_t req_type, uint16_t want_type, const char *unavail)
{
    uint32_t count = 0;
    char js[MEOW_IPC_MAX];
    uint16_t rt = 0;
    int rc = ipc_pm_send(req_type, &count, sizeof count, &rt, js, sizeof js);
    if (rc <= 0)
        return send_err(sock, 503, "POWER_UNAVAILABLE", unavail);
    if (rt != want_type || !utf8_valid_n(js, strlen(js)))
        return send_err(sock, 503, "POWER_UNAVAILABLE", "电源管理服务应答包含非法字节");
    return send_json(sock, 200, js);
}

int api_power_history(int sock)
{ return api_power_window(sock, MSG_PM_HISTORY, MSG_PM_HISTORY_RESULT, "电源历史采样不可用（powermgr 未运行）"); }

int api_power_events(int sock)
{ return api_power_window(sock, MSG_PM_EVENTS, MSG_PM_EVENTS_RESULT, "电源事件不可用（powermgr 未运行）"); }