refactor: modularize into core/events/formatters/drivers

src/github/store.ts

@@ -0,0 +1,92 @@
+interface StoredToken {
+  userId: string;
+  accessToken: string;
+  expiresAt: number;
+  refreshToken?: string;
+}
+
+async function hashToken(token: string): Promise<string> {
+  const data = new TextEncoder().encode(token);
+  const hash = await crypto.subtle.digest("SHA-256", data);
+  return Array.from(new Uint8Array(hash))
+    .map((b) => b.toString(16).padStart(2, "0"))
+    .join("");
+}
+
+export async function saveToken(
+  kv: KVNamespace,
+  userId: string,
+  accessToken: string,
+  expiresInSeconds: number,
+  refreshToken?: string,
+): Promise<void> {
+  const token: StoredToken = {
+    userId,
+    accessToken,
+    expiresAt: Date.now() + expiresInSeconds * 1000,
+    refreshToken,
+  };
+  const ttl = Math.max(Math.floor(expiresInSeconds * 0.9), 60);
+  await kv.put(`token:${userId}`, JSON.stringify(token), { expirationTtl: ttl });
+
+  const tokenHash = await hashToken(accessToken);
+  await kv.put(`token-reverse:${tokenHash}`, userId, { expirationTtl: ttl });
+}
+
+export async function getToken(kv: KVNamespace, userId: string): Promise<string | null> {
+  const raw = await kv.get(`token:${userId}`, "json");
+  if (!raw) return null;
+  const t = raw as StoredToken;
+  if (Date.now() >= t.expiresAt) {
+    await kv.delete(`token:${userId}`);
+    return null;
+  }
+  return t.accessToken;
+}
+
+export async function getRefreshToken(kv: KVNamespace, userId: string): Promise<string | null> {
+  const raw = await kv.get(`token:${userId}`, "json");
+  if (!raw) return null;
+  return (raw as StoredToken).refreshToken ?? null;
+}
+
+export async function removeToken(kv: KVNamespace, userId: string): Promise<void> {
+  const raw = await kv.get(`token:${userId}`, "json");
+  if (raw) {
+    const t = raw as StoredToken;
+    const tokenHash = await hashToken(t.accessToken);
+    await kv.delete(`token-reverse:${tokenHash}`);
+  }
+  await kv.delete(`token:${userId}`);
+}
+
+export async function findUserIdByToken(
+  kv: KVNamespace,
+  accessToken: string,
+): Promise<string | null> {
+  const tokenHash = await hashToken(accessToken);
+  return await kv.get(`token-reverse:${tokenHash}`, "text");
+}
+
+/**
+ * Link a Discord user id to a GitHub user id so that bot commands can act
+ * as that GitHub account. The actual OAuth token lives under `token:{githubUserId}`.
+ */
+export async function saveDiscordLink(
+  kv: KVNamespace,
+  discordUserId: string,
+  githubUserId: string,
+): Promise<void> {
+  await kv.put(`discord-link:${discordUserId}`, githubUserId);
+}
+
+export async function getDiscordLink(
+  kv: KVNamespace,
+  discordUserId: string,
+): Promise<string | null> {
+  return await kv.get(`discord-link:${discordUserId}`, "text");
+}
+
+export async function removeDiscordLink(kv: KVNamespace, discordUserId: string): Promise<void> {
+  await kv.delete(`discord-link:${discordUserId}`);
+}