import assert from 'assert';
import axios, { AxiosInstance } from 'axios';
import {
  ConductorSDKOptions,
  StartWorkflowOptions,
  Workflow,
  WorkflowDefinition,
  WorkflowMetadataDefinition,
} from './index';

interface RerunWorkflowOptions {
  reRunFromWorkflowId: string;
  workflowInput: any;
  reRunFromTaskId: string;
  taskInput: any;
}

interface SkipWorkflowTaskOptions {
  taskReferenceName: string;
  taskInput: any;
  taskOutput: any;
}

class WorkflowManager {
  options: ConductorSDKOptions;
  client: AxiosInstance;

  constructor(options: ConductorSDKOptions = {}) {
    this.options = options;

    const { apiEndpoint } = this.options;
    assert(apiEndpoint, 'apiEndpoint is empty');

    this.client = axios.create({
      baseURL: apiEndpoint,
      responseType: 'json',
    });
  }

  /**
   * Get Workflow State by workflow Id. If includeTasks is set, then also includes all the tasks executed and scheduled.
   */
  async retrieveWorkflow<INPUT = any, OUTPUT = any>(workflowId: string, includeTasks = false) {
    const params = { includeTasks };
    const { data } = await this.client.get<Workflow<INPUT, OUTPUT>>('/workflow/' + workflowId, { params });
    return data;
  }

  async startWorkflow(options: StartWorkflowOptions) {
    const { data: workflowId } = await this.client.post<string>('/workflow', options);
    const workflow = await this.retrieveWorkflow(workflowId);
    assert(workflow.workflowId === workflowId, 'Start a workflow, but can not find it');
    return workflow;
  }

  async terminateWorkflow(workflowId: string) {
    const workflow = await this.retrieveWorkflow(workflowId);
    await this.client.delete<string>('/workflow/' + workflowId);
    return workflow;
  }

  async removeWorkflow(workflowId: string) {
    const workflow = await this.retrieveWorkflow(workflowId);
    await this.client.delete<string>('/workflow/' + workflowId + '/remove');
    return workflow;
  }

  /**
   * Pause. No further tasks will be scheduled until resumed. Currently running tasks are not paused.
   * @param workflowId
   */
  async pauseWorkflow(workflowId: string) {
    const workflow = await this.retrieveWorkflow(workflowId);
    await this.client.put<string>('/workflow/' + workflowId + '/pause');
    return workflow;
  }

  /**
   * Resume normal operations after a pause.
   * @param workflowId
   */
  async resumeWorkflow(workflowId: string) {
    const workflow = await this.retrieveWorkflow(workflowId);
    await this.client.put<string>('/workflow/' + workflowId + '/resume');
    return workflow;
  }

  /**
   * Re-runs a completed workflow from a specific task.
   * @param workflowId
   * @param options
   */
  async rerunWorkflow(workflowId: string, options: RerunWorkflowOptions) {
    const { data } = await this.client.post<string>('/workflow/' + workflowId + '/rerun', options);
    const workflow = await this.retrieveWorkflow(workflowId);
    return workflow;
  }

  /**
   * Restart workflow execution from the start. Current execution history is wiped out.
   * @param workflowId
   */
  async restartWorkflow(workflowId: string) {
    const workflow = await this.retrieveWorkflow(workflowId);
    await this.client.post<string>('/workflow/' + workflowId + '/restart');
    return workflow;
  }

  /**
   * Retry the last failed task.
   * @param workflowId
   */
  async retryWorkflow(workflowId: string) {
    const workflow = await this.retrieveWorkflow(workflowId);
    await this.client.post<string>('/workflow/' + workflowId + '/retry');
    return workflow;
  }

  /**
   * Skips a task execution (specified as taskReferenceName parameter) in a running workflow and continues forward.
   * Optionally updating task's input and output as specified in the payload.
   * PUT /workflow/{workflowId}/skiptask/{taskReferenceName}?workflowId=&taskReferenceName=
   * @param workflowId
   * @param options
   */
  async skipWorkflowTask(workflowId: string, options: SkipWorkflowTaskOptions) {
    assert(options.taskReferenceName, 'taskReferenceName should be not empty');
    const { taskReferenceName, ...others } = options;
    const { data } = await this.client.put<string>(
      '/workflow/' + workflowId + '/skiptask/' + taskReferenceName,
      others,
    );
    const workflow = await this.retrieveWorkflow(workflowId);
    return workflow;
  }
}

export default WorkflowManager;
export { WorkflowManager };