feat: 监控上传图片压缩

src/hooks/useClassMonitor.ts

@@ -15,6 +15,9 @@ const MONITOR_SNAPSHOT_INTERVAL = 10000
 const MONITOR_MSG_TYPE = 'monitorStart'
 const MONITOR_STOP_MSG_TYPE = 'monitorStop'
 const MONITOR_LOG_PREFIX = '[class-monitor]'
+const MONITOR_SNAPSHOT_TARGET_SIZE = 100 * 1024
+const MONITOR_SNAPSHOT_MIN_WIDTH = 480
+const MONITOR_SNAPSHOT_MIN_HEIGHT = 270
 
 const monitorLog = (...args: unknown[]) => console.log(MONITOR_LOG_PREFIX, ...args)
 const monitorWarn = (...args: unknown[]) => console.warn(MONITOR_LOG_PREFIX, ...args)
@@ -119,20 +122,84 @@ const prepareMonitorDomForCapture = async () => {
   })
 }
 
-const canvasToPngFile = (canvas: HTMLCanvasElement) =>
-  new Promise<File | null>(resolve => {
-    canvas.toBlob(blob => {
-      if (!blob) return resolve(null)
-      resolve(new File([blob], `monitor-${Date.now()}.png`, { type: 'image/png' }))
-    }, 'image/png')
+const canvasToBlob = (canvas: HTMLCanvasElement, type: string, quality?: number) =>
+  new Promise<Blob | null>(resolve => {
+    canvas.toBlob(
+      blob => {
+        resolve(blob)
+      },
+      type,
+      quality,
+    )
   })
 
+const resizeCanvas = (source: HTMLCanvasElement, ratio: number) => {
+  const canvas = document.createElement('canvas')
+  canvas.width = Math.max(1, Math.round(source.width * ratio))
+  canvas.height = Math.max(1, Math.round(source.height * ratio))
+  const ctx = canvas.getContext('2d')
+  if (!ctx) return source
+  ctx.drawImage(source, 0, 0, canvas.width, canvas.height)
+  return canvas
+}
+
+const canvasToMonitorFile = async (canvas: HTMLCanvasElement) => {
+  const qualities = [0.72, 0.6, 0.5, 0.42, 0.35, 0.3, 0.25]
+  let current = canvas
+  let bestBlob: Blob | null = null
+  let bestInfo = {
+    width: canvas.width,
+    height: canvas.height,
+    quality: qualities[0],
+  }
+
+  for (let resizeCount = 0; resizeCount < 8; resizeCount++) {
+    for (const quality of qualities) {
+      const blob = await canvasToBlob(current, 'image/jpeg', quality)
+      if (!blob) return null
+      if (!bestBlob || blob.size < bestBlob.size) {
+        bestBlob = blob
+        bestInfo = {
+          width: current.width,
+          height: current.height,
+          quality,
+        }
+      }
+      if (blob.size <= MONITOR_SNAPSHOT_TARGET_SIZE) {
+        monitorLog('web screenshot compressed', {
+          width: current.width,
+          height: current.height,
+          quality,
+          size: blob.size,
+        })
+        return new File([blob], `monitor-${Date.now()}.jpg`, { type: 'image/jpeg' })
+      }
+    }
+
+    if (
+      current.width <= MONITOR_SNAPSHOT_MIN_WIDTH ||
+      current.height <= MONITOR_SNAPSHOT_MIN_HEIGHT
+    ) {
+      break
+    }
+    current = resizeCanvas(current, 0.85)
+  }
+
+  if (!bestBlob) return null
+  monitorWarn('web screenshot compressed but still over target', {
+    ...bestInfo,
+    size: bestBlob.size,
+    target: MONITOR_SNAPSHOT_TARGET_SIZE,
+  })
+  return new File([bestBlob], `monitor-${Date.now()}.jpg`, { type: 'image/jpeg' })
+}
+
 const createWebScreenshotFile = async (): Promise<File | null> => {
   await prepareMonitorDomForCapture()
 
   const vw = window.innerWidth
   const vh = window.innerHeight
-  const scale = Math.min(window.devicePixelRatio || 1, 2)
+  const scale = Math.min(window.devicePixelRatio || 1, 1)
   monitorLog('web screenshot start', {
     href: window.location.href,
     viewport: `${vw}x${vh}`,
@@ -200,7 +267,7 @@ const createWebScreenshotFile = async (): Promise<File | null> => {
         monitorWarn('web screenshot canvas empty', index + 1)
         continue
       }
-      const file = await canvasToPngFile(canvas)
+      const file = await canvasToMonitorFile(canvas)
       if (file) {
         monitorLog('web screenshot file ready', {
           attempt: index + 1,