初始化版本

api/save_avatar.php

@@ -0,0 +1,61 @@
+<?php
+// 保存头像到本地（避免重复），不进行过期清理
+header('Content-Type: application/json; charset=utf-8');
+
+function respond($ok, $message = '', $path = '') {
+    echo json_encode(['success' => $ok, 'message' => $message, 'path' => $path], JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
+    exit;
+}
+
+$raw = file_get_contents('php://input');
+$data = json_decode($raw, true);
+$url = $data['url'] ?? '';
+if (!$url || !filter_var($url, FILTER_VALIDATE_URL)) {
+    respond(false, 'URL无效');
+}
+
+$scheme = parse_url($url, PHP_URL_SCHEME);
+if (!in_array(strtolower($scheme), ['http','https'])) {
+    respond(false, '仅支持http/https图片地址');
+}
+
+$avatarsRoot = __DIR__ . '/../avatars';
+if (!is_dir($avatarsRoot)) { @mkdir($avatarsRoot, 0777, true); }
+$today = (new DateTime('now'))->format('Y-m-d');
+$targetDir = $avatarsRoot . '/' . $today;
+if (!is_dir($targetDir)) { @mkdir($targetDir, 0777, true); }
+
+// 推断扩展名
+$pathExt = strtolower(pathinfo(parse_url($url, PHP_URL_PATH) ?? '', PATHINFO_EXTENSION));
+$allowed = ['jpg','jpeg','png','gif','webp'];
+if (!$pathExt || !in_array($pathExt, $allowed)) { $pathExt = 'jpg'; }
+
+// 使用URL的basename作为文件名，若没有则用hash
+$basename = basename(parse_url($url, PHP_URL_PATH) ?: '');
+if (!$basename || $basename === '/' || $basename === '\\') {
+    $basename = md5($url) . '.' . $pathExt;
+}
+if (strpos($basename, '.') === false) { $basename .= '.' . $pathExt; }
+$safeName = preg_replace('/[^\w\.-]+/u', '_', $basename);
+$targetPath = $targetDir . '/' . $safeName;
+
+// 如果已存在，跳过下载
+if (file_exists($targetPath)) {
+    respond(true, '文件已存在，跳过下载', str_replace($_SERVER['DOCUMENT_ROOT'], '', $targetPath));
+}
+
+// 下载保存
+try {
+    $read = @fopen($url, 'rb');
+    if (!$read) { respond(false, '无法读取远程图片'); }
+    $write = @fopen($targetPath, 'wb');
+    if (!$write) { respond(false, '无法写入文件'); }
+    stream_copy_to_stream($read, $write);
+    fclose($read);
+    fclose($write);
+} catch (Throwable $e) {
+    respond(false, '保存失败: ' . $e->getMessage());
+}
+
+respond(true, '保存成功', str_replace($_SERVER['DOCUMENT_ROOT'], '', $targetPath));
+