/* mp_files.c — 文件域：路径安全/白名单 + /api/files* + multipart 上传解析 + 卡根派生路径。 */
#include "mp.h"

char g_tf_root_buf[1024] = "/usr/data/mnt/sd_0";
char g_tf_card_buf[2048], g_apps_dir_buf[2048], g_logs_dir_buf[2048], g_notif_log_buf[2048];
const char *g_tf_card = NULL, *g_apps_dir = NULL, *g_logs_dir = NULL, *g_notif_log = NULL;
const char *g_allowed_dirs[] = { "MeowOS", "Music", "MeowData", "MeowAPPs", "book" };
#define ALLOWED_COUNT ((int)(sizeof g_allowed_dirs / sizeof g_allowed_dirs[0]))
const char *g_sensitive_names[] = {
    "settings.conf", "setting.bak", ".env", "passwd", "shadow",
    "meow.conf", "user.ini", "config.json",
};
#define SENSITIVE_COUNT ((int)(sizeof g_sensitive_names / sizeof g_sensitive_names[0]))


void init_tf_paths(void)
{
    const char *env = getenv("MEOW_TF_ROOT");
    if (env && env[0]) {
        snprintf(g_tf_root_buf, sizeof g_tf_root_buf, "%s", env);
        /* 去掉末尾 `/`（规范化处统一按无尾斜杠处理） */
        size_t l = strlen(g_tf_root_buf);
        while (l > 1 && g_tf_root_buf[l - 1] == '/') g_tf_root_buf[--l] = 0;
    }
    snprintf(g_tf_card_buf, sizeof g_tf_card_buf, "%s/MeowOS", TF_ROOT);
    snprintf(g_apps_dir_buf, sizeof g_apps_dir_buf, "%s/MeowAPPs", TF_ROOT);
    snprintf(g_logs_dir_buf, sizeof g_logs_dir_buf, "%s/MeowOS/logs", TF_ROOT);
    snprintf(g_notif_log_buf, sizeof g_notif_log_buf, "%s/MeowOS/notifications/notifications.log", TF_ROOT);
    env = getenv("MEOW_NOTIF_LOG");
    if (env && env[0]) snprintf(g_notif_log_buf, sizeof g_notif_log_buf, "%s", env);
    g_tf_card  = g_tf_card_buf;
    g_apps_dir = g_apps_dir_buf;
    g_logs_dir = g_logs_dir_buf;
    g_notif_log = g_notif_log_buf;
}

int tf_present(void)
{
    if (getenv("MEOW_TF_ROOT")) return 1;   /* 宿主测试显式指定卡根（env 覆盖），信任其存在 */
    FILE *f = fopen("/proc/mounts", "r");
    if (!f) return 0;
    char line[512];
    int present = 0;
    while (fgets(line, sizeof line, f)) {
        if (strstr(line, TF_ROOT)) { present = 1; break; }
    }
    fclose(f);
    return present;
}

int path_in_whitelist(const char *abs)
{
    size_t rl = strlen(TF_ROOT);
    if (strncmp(abs, TF_ROOT, rl) != 0) return 0;
    if (abs[rl] == 0) return 1;                    /* 根自身 */
    if (abs[rl] != '/') return 0;
    const char *rest = abs + rl + 1;
    for (int i = 0; i < ALLOWED_COUNT; i++) {
        size_t dl = strlen(g_allowed_dirs[i]);
        if (strncmp(rest, g_allowed_dirs[i], dl) == 0) {
            if (rest[dl] == 0 || rest[dl] == '/') return 1;
        }
    }
    return 0;
}

int is_sensitive_name(const char *base)
{
    for (int i = 0; i < SENSITIVE_COUNT; i++)
        if (!strcmp(base, g_sensitive_names[i])) return 1;
    return 0;
}

int normalize_path(const char *in, char *buf, size_t buflen)
{
    size_t rl = strlen(TF_ROOT);
    if (strlen(in) > 900) return -1;                 /* 拒绝超长路径（防御；真实路径远小于此） */
    char joined[2048];
    if (in[0] == '/') {
        if (strncmp(in, TF_ROOT, rl) == 0 && (in[rl] == 0 || in[rl] == '/')) {
            snprintf(joined, sizeof joined, "%s", in);
        } else {
            /* 相对 root 的展示路径，如 /MeowOS/x → 拼到 root */
            if (in[0] == '/' && in[1] == '/') snprintf(joined, sizeof joined, "%s%s", TF_ROOT, in + 1);
            else if (in[0] == '/') snprintf(joined, sizeof joined, "%s%s", TF_ROOT, in);
            else snprintf(joined, sizeof joined, "%s/%s", TF_ROOT, in);
        }
    } else {
        snprintf(joined, sizeof joined, "%s/%s", TF_ROOT, in);
    }
    /* 逐分量规范化成**绝对**路径：/a/b/../c → /a/c；拒绝逃逸出 root。
     * 用绝对 out（以 '/' 开头）构建：首段即带前导 '/', 保证 path_in_whitelist 的绝对前缀比对成立。 */
    char out[2048];
    size_t n = 0;
    out[0] = '/';
    out[1] = 0;
    n = 1;
    char *p = joined;
    while (*p) {
        while (*p == '/') p++;
        if (!*p) break;
        char seg[256];
        int k = 0;
        while (*p && *p != '/') { if (k < 255) seg[k++] = *p; p++; }
        seg[k] = 0;
        if (!strcmp(seg, ".") || !strcmp(seg, "")) continue;
        if (!strcmp(seg, "..")) {
            /* 弹出一级；已在根(n==1)再 .. → 逃逸出 root，拒绝 */
            if (n <= 1) return -1;
            while (n > 1 && out[n - 1] != '/') n--;
            if (n > 1) n--;              /* 去掉结尾 /；out[n] 归属下一段或结束 */
            out[n] = 0;
            continue;
        }
        if (k > 0) {
            size_t need = n + ((n > 1) ? 1 : 0) + (size_t)k + 1;
            if (need >= sizeof out) return -1;
            if (n > 1) { out[n++] = '/'; out[n] = 0; }
            memcpy(out + n, seg, (size_t)k);
            n += (size_t)k;
            out[n] = 0;
        }
    }
    /* 空/根（n==1，仅 "/"）→ 卡根 */
    if (n <= 1) snprintf(out, sizeof out, "%s", TF_ROOT);
    size_t ol = strlen(out);
    if (ol >= buflen) return -1;
    memcpy(buf, out, ol + 1);        /* 已证明 ol<buflen，用 memcpy 避免 %s 截断告警 */
    return 0;
}

void make_rel(const char *abs, char *buf, size_t buflen)
{
    size_t rl = strlen(TF_ROOT);
    if (strncmp(abs, TF_ROOT, rl) != 0) { buf[0] = 0; return; }
    const char *rest = abs + rl;
    if (*rest == 0) snprintf(buf, buflen, "/");
    else snprintf(buf, buflen, "%s", rest);
}

int open_safe_for_read(const char *abs, int follow_rel)
{
    (void)follow_rel;
    if (!path_in_whitelist(abs)) return -1;
    const char *base = strrchr(abs, '/');
    base = base ? base + 1 : abs;
    if (is_sensitive_name(base)) return -1;
    struct stat st;
    if (stat(abs, &st) < 0) return -1;
    if (!S_ISREG(st.st_mode)) return -1;
    return open(abs, O_RDONLY);
}

void fmt_json_item(sbuf_t *s, const char *name, int isdir, long long size, long long mtime)
{
    sA(s, "{\"name\":");
    sA_str(s, name);
    sA(s, ",\"type\":\"%s\",\"size\":%lld,\"mtime\":%lld}",
        isdir ? "dir" : "file", size, mtime);
}

int nat_strcmp(const char *a, const char *b)
{
    const unsigned char *pa = (const unsigned char *)a;
    const unsigned char *pb = (const unsigned char *)b;
    while (*pa && *pb) {
        unsigned char ca = *pa, cb = *pb;
        if (ca >= '0' && ca <= '9' && cb >= '0' && cb <= '9') {
            const unsigned char *na = pa, *nb = pb;
            while (*na == '0') na++;
            while (*nb == '0') nb++;
            const unsigned char *da = na, *db = nb;
            while (*da >= '0' && *da <= '9') da++;
            while (*db >= '0' && *db <= '9') db++;
            int la = (int)(da - na), lb = (int)(db - nb);   /* 有效数字位数（去前导0） */
            if (la != lb) return la - lb;                   /* 位数小者数小 */
            int c = memcmp(na, nb, (size_t)la);
            if (c) return c;
            int ta = (int)(da - pa), tb = (int)(db - pb);   /* 原始数字串长（含前导0） */
            if (ta != tb) return ta - tb;
            pa = da; pb = db;
            continue;                                       /* 数字段完全相同，继续 */
        }
        unsigned char la = (ca >= 'A' && ca <= 'Z') ? (unsigned char)(ca + 32) : ca;
        unsigned char lbc = (cb >= 'A' && cb <= 'Z') ? (unsigned char)(cb + 32) : cb;
        if (la != lbc) return (int)la - (int)lbc;
        if (ca != cb) return (int)ca - (int)cb;             /* 大小写 tie-break：大写在前 */
        pa++; pb++;
    }
    return (int)*pa - (int)*pb;
}

int fent_cmp(const void *a, const void *b)
{
    const struct fent *fa = a, *fb = b;
    if (fa->isdir != fb->isdir) return fb->isdir - fa->isdir;
    return nat_strcmp(fa->name, fb->name);
}

int files_list(int sock, const char *relpath)
{
    char abs[1024], rel[1024];
    if (normalize_path(relpath, abs, sizeof abs) < 0)
        return send_err(sock, 403, "FORBIDDEN", "白名单外/路径逃逸");
    if (!path_in_whitelist(abs))
        return send_err(sock, 403, "FORBIDDEN", "白名单外/路径逃逸");
    struct stat st;
    if (stat(abs, &st) < 0)
        return send_err(sock, 404, "NOT_FOUND", "路径不存在");
    if (!S_ISDIR(st.st_mode))
        return send_err(sock, 404, "NOT_FOUND", "非目录");
    DIR *d = opendir(abs);
    if (!d)
        return send_err(sock, 500, "INTERNAL", "读目录失败");
    make_rel(abs, rel, sizeof rel);
    sbuf_t s = {0};
    sA(&s, "{\"root\":");
    sA_str(&s, TF_ROOT);
    sA(&s, ",\"path\":");
    sA_str(&s, abs);
    sA(&s, ",\"rel\":");
    sA_str(&s, rel);
    sA(&s, ",\"allowed\":[");
    for (int i = 0; i < ALLOWED_COUNT; i++) { if (i) sA(&s, ","); sA_str(&s, g_allowed_dirs[i]); }
    sA(&s, "],\"items\":[");
    /* M2.78：排序后输出（原 readdir 原始顺序混杂难用）——目录优先，同组按名称
     * 不区分大小写排序；条目上限 1024（与 files App 一致，防巨目录爆内存）。 */
    int cap = 1024, n = 0;
    struct fent *ents = malloc((size_t)cap * sizeof *ents);
    struct dirent *e;
    while ((e = readdir(d))) {
        if (!strcmp(e->d_name, ".") || !strcmp(e->d_name, "..")) continue;
        char full[1400];
        snprintf(full, sizeof full, "%s/%s", abs, e->d_name);
        struct stat fs;
        if (stat(full, &fs) < 0) continue;
        if (n >= cap) break;
        struct fent *en = &ents[n++];
        snprintf(en->name, sizeof en->name, "%s", e->d_name);
        en->isdir = S_ISDIR(fs.st_mode);
        en->size = en->isdir ? 0 : (long long)fs.st_size;
        en->mtime = (long long)fs.st_mtime;
    }
    closedir(d);
    qsort(ents, (size_t)n, sizeof *ents, fent_cmp);
    for (int i = 0; i < n; i++) {
        if (i) sA(&s, ",");
        fmt_json_item(&s, ents[i].name, ents[i].isdir, ents[i].size, ents[i].mtime);
    }
    free(ents);
    sA(&s, "]}");
    return send_json(sock, 200, s.b ? s.b : "");
}

char *read_text_file_limited(const char *abs, long long *size, int *truncated)
{
    int fd = open_safe_for_read(abs, 0);
    if (fd < 0) return NULL;
    struct stat st;
    if (fstat(fd, &st) < 0 || st.st_size < 0) { close(fd); return NULL; }
    long long total = (long long)st.st_size;
    size_t cap = total > TEXT_PREVIEW_MAX ? (size_t)TEXT_PREVIEW_MAX : (size_t)total;
    char *buf = malloc(cap + 1);
    if (!buf) { close(fd); return NULL; }
    ssize_t n = read(fd, buf, cap);
    close(fd);
    if (n < 0) { free(buf); return NULL; }
    buf[n] = 0;
    /* 二进制检测：含 NUL 或大量控制字符 */
    int ctrl = 0;
    for (ssize_t i = 0; i < n; i++) {
        unsigned char c = (unsigned char)buf[i];
        if (c == 0) { free(buf); return (char *)-2; }   /* 二进制 */
        if (c < 0x09) ctrl++;
    }
    if (ctrl > n / 10) { free(buf); return (char *)-2; }
    if (size) *size = total;
    if (truncated) *truncated = (total > (long long)cap) ? 1 : 0;
    return buf;
}

int safe_filename(const char *name, char *out, size_t cap)
{
    if (!name || !name[0]) return -1;
    const char *b = name;
    /* 取最后一个路径分隔符之后（同时兼容 '/' 与 '\\'） */
    const char *slash = strrchr(b, '/');
    const char *bsl = strrchr(b, '\\');
    if (bsl && (!slash || bsl > slash)) slash = bsl;
    if (slash) b = slash + 1;
    if (!b[0]) return -1;
    if (!strcmp(b, ".") || !strcmp(b, "..")) return -1;
    for (const char *p = b; *p; p++) {
        unsigned char c = (unsigned char)*p;
        if (c == '/' || c == '\\' || c < 0x20 || c == 0x7f) return -1;   /* 禁止分隔符/控制字符 */
    }
    snprintf(out, cap, "%s", b);
    return 0;
}

int parse_multipart(const req_t *r, upfile_t *files, int maxfiles)
{
    /* 取 boundary */
    const char *ct = r->content_type;
    const char *b = strstr(ct, "boundary=");
    if (!b) return -1;
    b += 9;
    if (*b == '"') { b++; }
    char boundary[128];
    int bi = 0;
    while (b[bi] && b[bi] != ';' && b[bi] != '"' && b[bi] != '\r' && bi < 120) { boundary[bi] = b[bi]; bi++; }
    boundary[bi] = 0;
    char dmark[160];
    snprintf(dmark, sizeof dmark, "--%s", boundary);
    char emark[160];
    snprintf(emark, sizeof emark, "--%s--", boundary);
    /* 块间以 \r\n--boundary 分隔；用 strstr 扫描 */
    const char *p = r->body;
    const char *end = r->body + r->body_len;
    int nfiles = 0;
    char curpath[1024] = "";
    while (p < end) {
        const char *fstart = mem_find(p, (size_t)(end - p), dmark);
        if (!fstart) break;
        fstart += strlen(dmark);
        if (*fstart == '-') break;    /* 结束标记 --boundary-- */
        if (*fstart == '\r' || *fstart == '\n') fstart++;
        /* 解析该 part 的头部（直至空行） */
        const char *headers_end = strstr(fstart, "\r\n\r\n");
        if (!headers_end) break;
        char hdr[512];
        size_t hl = (size_t)(headers_end - fstart);
        if (hl >= sizeof hdr) hl = sizeof hdr - 1;
        memcpy(hdr, fstart, hl);
        hdr[hl] = 0;
        const char *data_start = headers_end + 4;
        const char *name = NULL, *fname = NULL;
        char *save = NULL;
        for (char *ln = strtok_r(hdr, "\n", &save); ln; ln = strtok_r(NULL, "\n", &save)) {
            char *l = ln;
            while (*l == '\r' || *l == ' ' || *l == '\t') l++;
            if (strncasecmp(l, "Content-Disposition:", 20) == 0) {
                /* name 与 filename 常同行（name="file"; filename="up.txt"）。
                 * 先取 filename 再取 name——若先截断 name 收尾引号会把同行的 filename 一并截断。 */
                char *fn = strstr(l, "filename=\"");
                if (fn) { fn += 10; char *q = strchr(fn, '"'); if (q) { *q = 0; fname = fn; } }
                char *nm = strstr(l, "name=\"");
                if (nm) { nm += 6; char *q = strchr(nm, '"'); if (q) { *q = 0; name = nm; } }
            }
        }
        /* 数据结束：下一个 "--boundary" 之前（二进制安全） */
        const char *data_end = mem_find(data_start, (size_t)(end - data_start), dmark);
        if (!data_end) data_end = end;
        /* 去掉数据尾部 \r\n */
        while (data_end > data_start && (data_end[-1] == '\r' || data_end[-1] == '\n')) data_end--;
        if (name && !strcmp(name, "path")) {
            size_t dl = (size_t)(data_end - data_start);
            if (dl >= sizeof curpath) dl = sizeof curpath - 1;
            memcpy(curpath, data_start, dl);
            curpath[dl] = 0;
        } else if (name && !strcmp(name, "file") && fname && nfiles < maxfiles) {
            size_t dl = (size_t)(data_end - data_start);
            char safe[260];
            if (safe_filename(fname, safe, sizeof safe) < 0) { p = data_end; continue; }   /* 文件名非法：跳过该 part */
            /* 目标目录规范化 + 白名单校验 */
            char absdir[1024];
            if (normalize_path(curpath, absdir, sizeof absdir) < 0 || !path_in_whitelist(absdir)) { p = data_end; continue; }
            /* 拼绝对路径后再规范化 + 白名单复校（防拼接后残留逃逸） */
            char joined[1400];
            snprintf(joined, sizeof joined, "%s/%s", absdir, safe);
            char abs[1400];
            if (normalize_path(joined, abs, sizeof abs) < 0 || !path_in_whitelist(abs)) { p = data_end; continue; }
            snprintf(files[nfiles].filename, sizeof files[nfiles].filename, "%s", safe);
            snprintf(files[nfiles].path, sizeof files[nfiles].path, "%s", abs);
            int fd = open(abs, O_WRONLY | O_CREAT | O_TRUNC, 0644);
            if (fd >= 0) {
                write_full(fd, data_start, dl);
                close(fd);
                nfiles++;
            }
            /* fd<0（不可写）→ 不计数，跳过该文件 */
        }
        p = data_end;
    }
    return nfiles;   /* >=0：已保存文件数；-1 边界缺失/解析失败 */
}

int api_files_list(int sock, const req_t *r)
{
    if (!tf_present()) return send_err(sock, 503, "NO_CARD", "未识别到 TF 卡");
    char path[1024] = "/";
    if (r->query[0]) qparam(r->query, "path", path, sizeof path);
    return files_list(sock, path);
}

int api_files_read(int sock, const req_t *r)
{
    if (!tf_present()) return send_err(sock, 503, "NO_CARD", "未识别到 TF 卡");
    char path[1024];
    if (!qparam(r->query, "path", path, sizeof path)) return send_err(sock, 400, "BAD_REQUEST", "缺 path");
    char abs[1024];
    if (normalize_path(path, abs, sizeof abs) < 0 || !path_in_whitelist(abs)) return send_err(sock, 403, "FORBIDDEN", "白名单外/路径逃逸");
    long long size; int trunc;
    char *txt = read_text_file_limited(abs, &size, &trunc);
    if (txt == (char *)-2) return send_err(sock, 415, "UNSUPPORTED_MEDIA", "二进制文件不支持文本读取");
    if (!txt) return send_err(sock, 404, "NOT_FOUND", "文件不存在或过大");
    sbuf_t s = {0};
    sA(&s, "{\"path\":");
    sA_str(&s, abs);
    sA(&s, ",\"content\":");
    sA_str(&s, txt);
    sA(&s, ",\"size\":%lld,\"truncated\":%s}", size, trunc ? "true" : "false");
    free(txt);
    int rc = send_json(sock, 200, s.b ? s.b : "");
    sbuf_free(&s);
    return rc;
}

int api_files_download(int sock, const req_t *r)
{
    if (!tf_present()) return send_err(sock, 503, "NO_CARD", "未识别到 TF 卡");
    char path[1024];
    if (!qparam(r->query, "path", path, sizeof path)) return send_err(sock, 400, "BAD_REQUEST", "缺 path");
    char abs[1024];
    if (normalize_path(path, abs, sizeof abs) < 0 || !path_in_whitelist(abs)) return send_err(sock, 403, "FORBIDDEN", "白名单外/路径逃逸");
    const char *base = strrchr(abs, '/');
    base = base ? base + 1 : abs;
    if (is_sensitive_name(base)) return send_err(sock, 403, "FORBIDDEN", "敏感文件");
    return send_file(sock, 200, "application/octet-stream", abs, base);
}

int api_files_upload(int sock, const req_t *r)
{
    if (!tf_present()) return send_err(sock, 503, "NO_CARD", "未识别到 TF 卡");
    if (strncasecmp(r->content_type, "multipart/form-data", 19) != 0)
        return send_err(sock, 415, "UNSUPPORTED_MEDIA", "需 multipart/form-data");
    upfile_t files[16];
    memset(files, 0, sizeof files);
    int n = parse_multipart(r, files, 16);
    if (n < 0) return send_err(sock, 400, "BAD_REQUEST", "multipart 解析失败");
    sbuf_t s = {0};
    sA(&s, "{\"item\":[");
    int first = 1;
    for (int i = 0; i < n && i < 16; i++) {
        if (!files[i].filename[0]) continue;
        if (!strstr(files[i].path, "/")) continue;   /* 无目标目录的跳过 */
        struct stat st;
        if (stat(files[i].path, &st) < 0) continue;
        const char *base = strrchr(files[i].path, '/');
        base = base ? base + 1 : files[i].path;
        if (!first) sA(&s, ",");
        first = 0;
        sA(&s, "{\"name\":");
        sA_str(&s, base);
        sA(&s, ",\"type\":\"file\",\"size\":%lld,\"mtime\":%lld}",
            (long long)st.st_size, (long long)st.st_mtime);
    }
    sA(&s, "]}");
    int rc = send_json(sock, 200, s.b ? s.b : "");
    sbuf_free(&s);
    return rc;
}

int rm_recursive(const char *path)
{
    struct stat st;
    if (lstat(path, &st) < 0) return -1;
    if (S_ISDIR(st.st_mode)) {
        DIR *d = opendir(path);
        if (!d) return -1;
        struct dirent *e;
        while ((e = readdir(d))) {
            if (!strcmp(e->d_name, ".") || !strcmp(e->d_name, "..")) continue;
            char full[1024];
            snprintf(full, sizeof full, "%s/%s", path, e->d_name);
            rm_recursive(full);
        }
        closedir(d);
        return rmdir(path);
    }
    return unlink(path);
}

int api_files_mkdir(int sock, const req_t *r)
{
    if (!tf_present()) return send_err(sock, 503, "NO_CARD", "未识别到 TF 卡");
    if (!r->body || !r->body[0]) return send_err(sock, 400, "BAD_REQUEST", "缺 body");
    jv_t *root = jv_parse(r->body, (int)r->body_len);
    if (!root) return send_err(sock, 400, "BAD_REQUEST", "body 非合法 JSON");
    jv_t *pj = jv_obj_get(root, "path");
    if (!pj || pj->type != J_STR) { jv_free(root); return send_err(sock, 400, "BAD_REQUEST", "缺 path"); }
    char abs[1024];
    if (normalize_path(pj->str, abs, sizeof abs) < 0 || !path_in_whitelist(abs)) { jv_free(root); return send_err(sock, 403, "FORBIDDEN", "白名单外/路径逃逸"); }
    struct stat st;
    if (stat(abs, &st) == 0) { jv_free(root); return send_err(sock, 409, "CONFLICT", "目录已存在"); }
    if (mkdir(abs, 0755) < 0) { jv_free(root); return send_err(sock, 500, "INTERNAL", "创建目录失败"); }
    const char *base = strrchr(abs, '/');
    const char *b = base ? base + 1 : abs;
    sbuf_t s = {0};
    sA(&s, "{\"item\":{\"name\":");
    sA_str(&s, b);
    sA(&s, ",\"type\":\"dir\",\"size\":0,\"mtime\":%lld}}", (long long)time(NULL));
    jv_free(root);
    int rc = send_json(sock, 200, s.b ? s.b : "");
    sbuf_free(&s);
    return rc;
}

int api_files_rename(int sock, const req_t *r)
{
    if (!tf_present()) return send_err(sock, 503, "NO_CARD", "未识别到 TF 卡");
    if (!r->body || !r->body[0]) return send_err(sock, 400, "BAD_REQUEST", "缺 body");
    jv_t *root = jv_parse(r->body, (int)r->body_len);
    if (!root) return send_err(sock, 400, "BAD_REQUEST", "body 非合法 JSON");
    jv_t *pj = jv_obj_get(root, "path");
    jv_t *pnn = jv_obj_get(root, "new_name");
    if (!pj || pj->type != J_STR || !pnn || pnn->type != J_STR) { jv_free(root); return send_err(sock, 400, "BAD_REQUEST", "缺 path/new_name"); }
    if (strchr(pnn->str, '/')) { jv_free(root); return send_err(sock, 400, "BAD_REQUEST", "new_name 仅文件名"); }
    char abs[1024], newabs[1400];
    if (normalize_path(pj->str, abs, sizeof abs) < 0 || !path_in_whitelist(abs)) { jv_free(root); return send_err(sock, 403, "FORBIDDEN", "白名单外/路径逃逸"); }
    /* 新路径 = 原路径的**父目录** + new_name（new_name 仅文件名，不含分隔符） */
    char parent[1024];
    snprintf(parent, sizeof parent, "%s", abs);
    char *sl = strrchr(parent, '/');
    if (!sl || sl == parent) { jv_free(root); return send_err(sock, 400, "BAD_REQUEST", "无法重命名根路径"); }
    *sl = 0;
    if (!parent[0]) snprintf(parent, sizeof parent, "%s", TF_ROOT);   /* abs 顶层（如 /tmp/mptf/x）→ 父=根 */
    snprintf(newabs, sizeof newabs, "%s/%s", parent, pnn->str);
    /* newabs 复校白名单（new_name 无 /，父目录已校验；防御） */
    if (!path_in_whitelist(newabs)) { jv_free(root); return send_err(sock, 403, "FORBIDDEN", "白名单外/路径逃逸"); }
    if (rename(abs, newabs) < 0) { jv_free(root); return send_err(sock, 500, "INTERNAL", "重命名失败"); }
    sbuf_t s = {0};
    sA(&s, "{\"item\":{\"name\":");
    sA_str(&s, pnn->str);
    sA(&s, ",\"type\":\""); 
    struct stat st;
    if (stat(newabs, &st) == 0 && S_ISDIR(st.st_mode)) sA(&s, "dir"); else sA(&s, "file");
    sA(&s, "\",\"size\":%lld,\"mtime\":%lld}}", (long long)st.st_size, (long long)st.st_mtime);
    jv_free(root);
    int rc = send_json(sock, 200, s.b ? s.b : "");
    sbuf_free(&s);
    return rc;
}

int api_files_delete(int sock, const req_t *r)
{
    if (!tf_present()) return send_err(sock, 503, "NO_CARD", "未识别到 TF 卡");
    char path[1024];
    if (!qparam(r->query, "path", path, sizeof path)) return send_err(sock, 400, "BAD_REQUEST", "缺 path");
    char recursive[8] = "0";
    qparam(r->query, "recursive", recursive, sizeof recursive);
    char abs[1024];
    if (normalize_path(path, abs, sizeof abs) < 0 || !path_in_whitelist(abs)) return send_err(sock, 403, "FORBIDDEN", "白名单外/路径逃逸");
    if (!strcmp(abs, TF_ROOT)) return send_err(sock, 403, "FORBIDDEN", "禁止删除卡根");
    struct stat st;
    if (stat(abs, &st) < 0) return send_err(sock, 404, "NOT_FOUND", "路径不存在");
    if (S_ISDIR(st.st_mode) && atoi(recursive) != 1) {
        DIR *d = opendir(abs);
        int nonempty = 0;
        if (d) {
            struct dirent *e;
            while ((e = readdir(d))) {
                if (!strcmp(e->d_name, ".") || !strcmp(e->d_name, "..")) continue;
                nonempty = 1; break;
            }
            closedir(d);
        }
        if (nonempty) return send_err(sock, 409, "CONFLICT", "目录非空（需 recursive=1）");
    }
    if (rm_recursive(abs) < 0) return send_err(sock, 500, "INTERNAL", "删除失败");
    return send_json(sock, 200, "{\"removed\":true}");
}

int multipart_extract_file(const req_t *r, const char *outpath)
{
    const char *b = strstr(r->content_type, "boundary=");
    if (!b) return -1;
    b += 9;
    if (*b == '"') b++;
    char boundary[128]; int bi = 0;
    while (b[bi] && b[bi] != ';' && b[bi] != '"' && b[bi] != '\r' && bi < 120) { boundary[bi] = b[bi]; bi++; }
    boundary[bi] = 0;
    char dmark[160];
    snprintf(dmark, sizeof dmark, "--%s", boundary);
    const char *p = r->body;
    while (p < r->body + r->body_len) {
        const char *fs = strstr(p, dmark);
        if (!fs) break;
        fs += strlen(dmark);
        if (*fs == '-') break;
        if (*fs == '\r' || *fs == '\n') fs++;
        const char *he = strstr(fs, "\r\n\r\n");
        if (!he) break;
        char hdr[512];
        size_t hl = (size_t)(he - fs); if (hl >= sizeof hdr) hl = sizeof hdr - 1;
        memcpy(hdr, fs, hl); hdr[hl] = 0;
        int isfile = 0;
        char *save = NULL;
        for (char *ln = strtok_r(hdr, "\n", &save); ln; ln = strtok_r(NULL, "\n", &save)) {
            char *l = ln; while (*l == '\r' || *l == ' ' || *l == '\t') l++;
            if (strncasecmp(l, "Content-Disposition:", 20) == 0) {
                if (strstr(l, "name=\"file\"")) isfile = 1;
            }
        }
        const char *ds = he + 4;
        const char *de = mem_find(ds, (size_t)((r->body + r->body_len) - ds), dmark);
        if (!de) de = r->body + r->body_len;
        while (de > ds && (de[-1] == '\r' || de[-1] == '\n')) de--;
        if (isfile) {
            int fd = open(outpath, O_WRONLY | O_CREAT | O_TRUNC, 0644);
            if (fd < 0) return -1;
            write_full(fd, ds, (size_t)(de - ds));
            close(fd);
            return 0;
        }
        p = de;
    }
    return -1;
}