fix(canvas): 文本生成 - 修复分镜超时并贯通 Agent 与创作页流式返回

web/src/services/api/task-text-stream.ts

@@ -0,0 +1,57 @@
+export type TaskTextStreamEvent = {
+    event: string;
+    id?: number;
+    data?: unknown;
+};
+
+export type TaskTextStreamParser = {
+    buffer: string;
+};
+
+export function createTaskTextStreamParser(): TaskTextStreamParser {
+    return { buffer: "" };
+}
+
+export function consumeTaskTextStream(
+    parser: TaskTextStreamParser,
+    chunk: string,
+    onEvent: (event: TaskTextStreamEvent) => void,
+    flush = false,
+) {
+    parser.buffer += chunk;
+    for (;;) {
+        const boundary = parser.buffer.match(/\r?\n\r?\n/);
+        if (!boundary) break;
+        const index = boundary.index ?? 0;
+        emitTaskTextStreamBlock(parser.buffer.slice(0, index), onEvent);
+        parser.buffer = parser.buffer.slice(index + boundary[0].length);
+    }
+    if (flush && parser.buffer.trim()) {
+        emitTaskTextStreamBlock(parser.buffer, onEvent);
+        parser.buffer = "";
+    }
+}
+
+function emitTaskTextStreamBlock(block: string, onEvent: (event: TaskTextStreamEvent) => void) {
+    let event = "message";
+    let id: number | undefined;
+    const data: string[] = [];
+    for (const line of block.split(/\r?\n/)) {
+        if (!line || line.startsWith(":")) continue;
+        const separator = line.indexOf(":");
+        const field = separator >= 0 ? line.slice(0, separator) : line;
+        const value = separator >= 0 ? line.slice(separator + 1).replace(/^ /, "") : "";
+        if (field === "event") event = value || "message";
+        else if (field === "id" && /^\d+$/.test(value)) id = Number(value);
+        else if (field === "data") data.push(value);
+    }
+    if (!data.length) return;
+    const raw = data.join("\n");
+    let parsed: unknown;
+    try {
+        parsed = JSON.parse(raw);
+    } catch {
+        throw new Error("任务文本流返回了无效数据");
+    }
+    onEvent({ event, ...(id !== undefined ? { id } : {}), data: parsed });
+}