opencode-antigravity-auth/src/plugin/errors.ts

/**
 * Custom error types for opencode-antigravity-auth plugin.
 * 
 * Ported from LLM-API-Key-Proxy for robust error handling.
 */

/**
 * Error thrown when Antigravity returns an empty response after retry attempts.
 * 
 * Empty responses can occur when:
 * - The model has no candidates/choices
 * - The response body is empty or malformed
 * - A temporary service issue prevents generation
 */
export class EmptyResponseError extends Error {
  readonly provider: string;
  readonly model: string;
  readonly attempts: number;

  constructor(
    provider: string,
    model: string,
    attempts: number,
    message?: string,
  ) {
    super(
      message ??
        `The model returned an empty response after ${attempts} attempts. ` +
        `This may indicate a temporary service issue. Please try again.`,
    );
    this.name = "EmptyResponseError";
    this.provider = provider;
    this.model = model;
    this.attempts = attempts;
  }
}

/**
 * Error thrown when tool ID matching fails and cannot be recovered.
 */
export class ToolIdMismatchError extends Error {
  readonly expectedIds: string[];
  readonly foundIds: string[];

  constructor(expectedIds: string[], foundIds: string[], message?: string) {
    super(
      message ??
        `Tool ID mismatch: expected [${expectedIds.join(", ")}] but found [${foundIds.join(", ")}]`,
    );
    this.name = "ToolIdMismatchError";
    this.expectedIds = expectedIds;
    this.foundIds = foundIds;
  }
}