feat: img compress;perf: color.prompt response

src/utils/file.ts

@@ -190,3 +190,67 @@ export const fileToBase64 = (file: File) => {
     reader.onerror = (error) => reject(error);
   });
 };
+
+/**
+ * compress image. response base64
+ * @param maxSize The max size of the compressed image
+ */
+export const compressImg = ({
+  file,
+  maxW = 200,
+  maxH = 200,
+  maxSize = 1024 * 100
+}: {
+  file: File;
+  maxW?: number;
+  maxH?: number;
+  maxSize?: number;
+}) =>
+  new Promise<string>((resolve, reject) => {
+    const reader = new FileReader();
+    reader.readAsDataURL(file);
+    reader.onload = () => {
+      const img = new Image();
+      // @ts-ignore
+      img.src = reader.result;
+      img.onload = () => {
+        let width = img.width;
+        let height = img.height;
+
+        if (width > height) {
+          if (width > maxW) {
+            height *= maxW / width;
+            width = maxW;
+          }
+        } else {
+          if (height > maxH) {
+            width *= maxH / height;
+            height = maxH;
+          }
+        }
+
+        const canvas = document.createElement('canvas');
+        canvas.width = width;
+        canvas.height = height;
+        const ctx = canvas.getContext('2d');
+
+        if (!ctx) {
+          return reject('压缩图片异常');
+        }
+
+        ctx.drawImage(img, 0, 0, width, height);
+        const compressedDataUrl = canvas.toDataURL(file.type, 1);
+        // 移除 canvas 元素
+        canvas.remove();
+
+        if (compressedDataUrl.length > maxSize) {
+          return reject('图片太大了');
+        }
+        resolve(compressedDataUrl);
+      };
+    };
+    reader.onerror = (err) => {
+      console.log(err);
+      reject('压缩图片异常');
+    };
+  });