feat: improve copilot token refresh resilience

src/lib/copilot-token-manager.ts

@@ -0,0 +1,169 @@
+import consola from "consola"
+
+import { getCopilotToken } from "~/services/github/get-copilot-token"
+
+import { state } from "./state"
+
+/**
+ * Singleton manager for Copilot token with automatic refresh
+ * All token access should go through this manager
+ */
+class CopilotTokenManager {
+  private refreshTimer: ReturnType<typeof setTimeout> | null = null
+  private refreshPromise: Promise<void> | null = null
+  private tokenExpiresAt: number = 0
+  private consecutiveRefreshFailures: number = 0
+
+  /**
+   * Get the current valid Copilot token
+   * Automatically refreshes if expired or about to expire
+   */
+  async getToken(): Promise<string> {
+    // If no token or token is expired/expiring soon (within 60 seconds), refresh
+    const now = Date.now() / 1000
+    if (!state.copilotToken || this.tokenExpiresAt - now < 60) {
+      if (!this.refreshPromise) {
+        this.refreshPromise = this.refreshToken().finally(() => {
+          this.refreshPromise = null
+        })
+      }
+
+      try {
+        await this.refreshPromise
+      } catch (error) {
+        const nowAfterRefresh = Date.now() / 1000
+        const stillValid =
+          Boolean(state.copilotToken) && this.tokenExpiresAt - nowAfterRefresh > 5
+        if (stillValid && state.copilotToken) {
+          consola.warn(
+            "[CopilotTokenManager] Refresh failed but current token is still valid, using cached token:",
+            error,
+          )
+          return state.copilotToken
+        }
+        throw error
+      }
+    }
+
+    if (!state.copilotToken) {
+      throw new Error("Failed to obtain Copilot token")
+    }
+
+    return state.copilotToken
+  }
+
+  /**
+   * Force refresh the token and reset the auto-refresh timer
+   */
+  async refreshToken(): Promise<void> {
+    try {
+      consola.debug("[CopilotTokenManager] Refreshing token...")
+      const { token, expires_at, refresh_in } = await getCopilotToken()
+
+      state.copilotToken = token
+      this.tokenExpiresAt = expires_at
+
+      consola.debug("[CopilotTokenManager] Token refreshed successfully")
+      if (state.showToken) {
+        consola.info("[CopilotTokenManager] Token:", token)
+      }
+
+      this.consecutiveRefreshFailures = 0
+      // Setup auto-refresh timer
+      this.scheduleRefresh(refresh_in)
+    } catch (error) {
+      this.consecutiveRefreshFailures += 1
+      consola.error("[CopilotTokenManager] Failed to refresh token:", error)
+      throw error
+    }
+  }
+
+  /**
+   * Schedule the next automatic refresh
+   */
+  private scheduleRefresh(refreshIn: number): void {
+    // Clear existing timer
+    if (this.refreshTimer) {
+      clearTimeout(this.refreshTimer)
+      this.refreshTimer = null
+    }
+
+    // Schedule refresh 60 seconds before the recommended refresh time
+    const refreshMs = Math.min(
+      refreshIn * 1000,
+      Math.max((refreshIn - 60) * 1000, 60000), // At least 1 minute
+    )
+
+    consola.debug(
+      `[CopilotTokenManager] Scheduling next refresh in ${Math.round(refreshMs / 1000)}s`,
+    )
+
+    this.refreshTimer = setTimeout(async () => {
+      try {
+        await this.refreshToken()
+      } catch (error) {
+        consola.error(
+          "[CopilotTokenManager] Auto-refresh failed, scheduling background retry:",
+          error,
+        )
+        this.scheduleRetryAfterFailure()
+      }
+    }, refreshMs)
+  }
+
+  private scheduleRetryAfterFailure(): void {
+    if (this.refreshTimer) {
+      clearTimeout(this.refreshTimer)
+      this.refreshTimer = null
+    }
+
+    const cappedFailures = Math.min(this.consecutiveRefreshFailures, 6)
+    const retryDelaySeconds = Math.min(
+      15 * 2 ** Math.max(cappedFailures - 1, 0),
+      300,
+    )
+
+    consola.warn(
+      `[CopilotTokenManager] Scheduling retry after refresh failure in ${retryDelaySeconds}s`,
+    )
+
+    this.refreshTimer = setTimeout(async () => {
+      try {
+        await this.refreshToken()
+      } catch (error) {
+        consola.error(
+          "[CopilotTokenManager] Retry refresh failed, will retry again:",
+          error,
+        )
+        this.scheduleRetryAfterFailure()
+      }
+    }, retryDelaySeconds * 1000)
+  }
+
+  /**
+   * Clear the token and stop auto-refresh
+   * Call this when switching accounts or logging out
+   */
+  clear(): void {
+    if (this.refreshTimer) {
+      clearTimeout(this.refreshTimer)
+      this.refreshTimer = null
+    }
+    this.refreshPromise = null
+    state.copilotToken = undefined
+    this.tokenExpiresAt = 0
+    this.consecutiveRefreshFailures = 0
+    consola.debug("[CopilotTokenManager] Token cleared")
+  }
+
+  /**
+   * Check if we have a valid token
+   */
+  hasValidToken(): boolean {
+    const now = Date.now() / 1000
+    return Boolean(state.copilotToken) && this.tokenExpiresAt - now > 60
+  }
+}
+
+// Export singleton instance
+export const copilotTokenManager = new CopilotTokenManager()