import { Mutant } from '@stryker-mutator/api/core';
import { Logger } from '@stryker-mutator/api/logging';

import { ChildProcessCrashedError } from '../child-proxy/child-process-crashed-error.js';
import { OutOfMemoryError } from '../child-proxy/out-of-memory-error.js';
import { ResourceDecorator } from '../concurrent/index.js';

import { CheckerResource } from './checker-resource.js';

export class CheckerRetryDecorator
  extends ResourceDecorator<CheckerResource>
  implements CheckerResource
{
  constructor(
    producer: () => CheckerResource,
    private readonly log: Logger,
  ) {
    super(producer);
  }

  public async check(
    checkerName: string,
    mutants: Mutant[],
  ): ReturnType<CheckerResource['check']> {
    return this.tryAction(() => this.innerResource.check(checkerName, mutants));
  }

  public async group(
    checkerName: string,
    mutants: Mutant[],
  ): ReturnType<CheckerResource['group']> {
    return this.tryAction(() => this.innerResource.group(checkerName, mutants));
  }

  private async tryAction<T>(act: () => Promise<T>): Promise<T> {
    try {
      return await act();
    } catch (error) {
      if (error instanceof ChildProcessCrashedError) {
        if (error instanceof OutOfMemoryError) {
          this.log.warn(
            `Checker process [${error.pid}] ran out of memory. Retrying in a new process.`,
          );
        } else {
          this.log.warn(
            `Checker process [${error.pid}] crashed with exit code ${error.exitCode}. Retrying in a new process.`,
            error,
          );
        }
        await this.recover();
        return act();
      } else {
        throw error; //oops
      }
    }
  }
}