feat: add Signal provider support

src/signal/client.ts

@@ -0,0 +1,187 @@
+import { randomUUID } from "node:crypto";
+
+export type SignalRpcOptions = {
+  baseUrl: string;
+  timeoutMs?: number;
+};
+
+export type SignalRpcError = {
+  code?: number;
+  message?: string;
+  data?: unknown;
+};
+
+export type SignalRpcResponse<T> = {
+  jsonrpc?: string;
+  result?: T;
+  error?: SignalRpcError;
+  id?: string | number | null;
+};
+
+export type SignalSseEvent = {
+  event?: string;
+  data?: string;
+  id?: string;
+};
+
+const DEFAULT_TIMEOUT_MS = 10_000;
+
+function normalizeBaseUrl(url: string): string {
+  const trimmed = url.trim();
+  if (!trimmed) {
+    throw new Error("Signal base URL is required");
+  }
+  if (/^https?:\/\//i.test(trimmed)) return trimmed.replace(/\/+$/, "");
+  return `http://${trimmed}`.replace(/\/+$/, "");
+}
+
+async function fetchWithTimeout(
+  url: string,
+  init: RequestInit,
+  timeoutMs: number,
+) {
+  const controller = new AbortController();
+  const timer = setTimeout(() => controller.abort(), timeoutMs);
+  try {
+    return await fetch(url, { ...init, signal: controller.signal });
+  } finally {
+    clearTimeout(timer);
+  }
+}
+
+export async function signalRpcRequest<T = unknown>(
+  method: string,
+  params: Record<string, unknown> | undefined,
+  opts: SignalRpcOptions,
+): Promise<T> {
+  const baseUrl = normalizeBaseUrl(opts.baseUrl);
+  const id = randomUUID();
+  const body = JSON.stringify({
+    jsonrpc: "2.0",
+    method,
+    params,
+    id,
+  });
+  const res = await fetchWithTimeout(
+    `${baseUrl}/api/v1/rpc`,
+    {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      body,
+    },
+    opts.timeoutMs ?? DEFAULT_TIMEOUT_MS,
+  );
+  if (res.status === 201) {
+    return undefined as T;
+  }
+  const text = await res.text();
+  if (!text) {
+    throw new Error(`Signal RPC empty response (status ${res.status})`);
+  }
+  const parsed = JSON.parse(text) as SignalRpcResponse<T>;
+  if (parsed.error) {
+    const code = parsed.error.code ?? "unknown";
+    const msg = parsed.error.message ?? "Signal RPC error";
+    throw new Error(`Signal RPC ${code}: ${msg}`);
+  }
+  return parsed.result as T;
+}
+
+export async function signalCheck(
+  baseUrl: string,
+  timeoutMs = DEFAULT_TIMEOUT_MS,
+): Promise<{ ok: boolean; status?: number | null; error?: string | null }> {
+  const normalized = normalizeBaseUrl(baseUrl);
+  try {
+    const res = await fetchWithTimeout(
+      `${normalized}/api/v1/check`,
+      { method: "GET" },
+      timeoutMs,
+    );
+    if (!res.ok) {
+      return { ok: false, status: res.status, error: `HTTP ${res.status}` };
+    }
+    return { ok: true, status: res.status, error: null };
+  } catch (err) {
+    return {
+      ok: false,
+      status: null,
+      error: err instanceof Error ? err.message : String(err),
+    };
+  }
+}
+
+export async function streamSignalEvents(params: {
+  baseUrl: string;
+  account?: string;
+  abortSignal?: AbortSignal;
+  onEvent: (event: SignalSseEvent) => void;
+}): Promise<void> {
+  const baseUrl = normalizeBaseUrl(params.baseUrl);
+  const url = new URL(`${baseUrl}/api/v1/events`);
+  if (params.account) url.searchParams.set("account", params.account);
+
+  const res = await fetch(url, {
+    method: "GET",
+    headers: { Accept: "text/event-stream" },
+    signal: params.abortSignal,
+  });
+  if (!res.ok || !res.body) {
+    throw new Error(
+      `Signal SSE failed (${res.status} ${res.statusText || "error"})`,
+    );
+  }
+
+  const reader = res.body.getReader();
+  const decoder = new TextDecoder();
+  let buffer = "";
+  let currentEvent: SignalSseEvent = {};
+
+  const flushEvent = () => {
+    if (!currentEvent.data && !currentEvent.event && !currentEvent.id) return;
+    params.onEvent({
+      event: currentEvent.event,
+      data: currentEvent.data,
+      id: currentEvent.id,
+    });
+    currentEvent = {};
+  };
+
+  while (true) {
+    const { value, done } = await reader.read();
+    if (done) break;
+    buffer += decoder.decode(value, { stream: true });
+    let lineEnd = buffer.indexOf("\n");
+    while (lineEnd !== -1) {
+      let line = buffer.slice(0, lineEnd);
+      buffer = buffer.slice(lineEnd + 1);
+      if (line.endsWith("\r")) line = line.slice(0, -1);
+
+      if (line === "") {
+        flushEvent();
+        lineEnd = buffer.indexOf("\n");
+        continue;
+      }
+      if (line.startsWith(":")) {
+        lineEnd = buffer.indexOf("\n");
+        continue;
+      }
+      const [rawField, ...rest] = line.split(":");
+      const field = rawField.trim();
+      const rawValue = rest.join(":");
+      const value = rawValue.startsWith(" ") ? rawValue.slice(1) : rawValue;
+      if (field === "event") {
+        currentEvent.event = value;
+      } else if (field === "data") {
+        currentEvent.data = currentEvent.data
+          ? `${currentEvent.data}\n${value}`
+          : value;
+      } else if (field === "id") {
+        currentEvent.id = value;
+      }
+      lineEnd = buffer.indexOf("\n");
+    }
+  }
+
+  flushEvent();
+}