/* eslint-disable prefer-template */
/* eslint-disable @typescript-eslint/restrict-plus-operands */
/* eslint-disable @typescript-eslint/no-unnecessary-type-assertion */
/* eslint-disable no-param-reassign */
/* eslint-disable @typescript-eslint/no-unsafe-call */
/* eslint-disable @typescript-eslint/no-non-null-assertion */
/* eslint-disable @typescript-eslint/no-unsafe-assignment */
import { IRun } from 'n8n-workflow';

import { createDeferredPromise } from 'n8n-core';

import { ChildProcess } from 'child_process';
// eslint-disable-next-line import/no-extraneous-dependencies
import * as PCancelable from 'p-cancelable';
// eslint-disable-next-line import/no-cycle
import {
	Db,
	IExecutingWorkflowData,
	IExecutionDb,
	IExecutionFlattedDb,
	IExecutionsCurrentSummary,
	IWorkflowExecutionDataProcess,
	ResponseHelper,
	WorkflowHelpers,
} from '.';

export class ActiveExecutions {
	private activeExecutions: {
		[index: string]: IExecutingWorkflowData;
	} = {};

	/**
	 * Add a new active execution
	 *
	 * @param {ChildProcess} process
	 * @param {IWorkflowExecutionDataProcess} executionData
	 * @returns {string}
	 * @memberof ActiveExecutions
	 */
	async add(
		executionData: IWorkflowExecutionDataProcess,
		process?: ChildProcess,
		executionId?: string,
	): Promise<string> {
		if (executionId === undefined) {
			// Is a new execution so save in DB

			const fullExecutionData: IExecutionDb = {
				data: executionData.executionData!,
				mode: executionData.executionMode,
				finished: false,
				startedAt: new Date(),
				workflowData: executionData.workflowData,
			};

			if (executionData.retryOf !== undefined) {
				fullExecutionData.retryOf = executionData.retryOf.toString();
			}

			if (
				executionData.workflowData.id !== undefined &&
				WorkflowHelpers.isWorkflowIdValid(executionData.workflowData.id.toString())
			) {
				fullExecutionData.workflowId = executionData.workflowData.id.toString();
			}

			const execution = ResponseHelper.flattenExecutionData(fullExecutionData);

			const executionResult = await Db.collections.Execution!.save(
				execution as IExecutionFlattedDb,
			);
			executionId =
				typeof executionResult.id === 'object'
					? // @ts-ignore
					  executionResult.id!.toString()
					: executionResult.id + '';
		} else {
			// Is an existing execution we want to finish so update in DB

			const execution = {
				id: executionId,
				waitTill: null,
			};

			// @ts-ignore
			await Db.collections.Execution!.update(executionId, execution);
		}

		// @ts-ignore
		this.activeExecutions[executionId] = {
			executionData,
			process,
			startedAt: new Date(),
			postExecutePromises: [],
		};

		// @ts-ignore
		return executionId;
	}

	/**
	 * Attaches an execution
	 *
	 * @param {string} executionId
	 * @param {PCancelable<IRun>} workflowExecution
	 * @memberof ActiveExecutions
	 */
	// eslint-disable-next-line @typescript-eslint/explicit-module-boundary-types
	attachWorkflowExecution(executionId: string, workflowExecution: PCancelable<IRun>) {
		if (this.activeExecutions[executionId] === undefined) {
			throw new Error(
				`No active execution with id "${executionId}" got found to attach to workflowExecution to!`,
			);
		}

		this.activeExecutions[executionId].workflowExecution = workflowExecution;
	}

	/**
	 * Remove an active execution
	 *
	 * @param {string} executionId
	 * @param {IRun} fullRunData
	 * @returns {void}
	 * @memberof ActiveExecutions
	 */
	remove(executionId: string, fullRunData?: IRun): void {
		if (this.activeExecutions[executionId] === undefined) {
			return;
		}

		// Resolve all the waiting promises
		// eslint-disable-next-line no-restricted-syntax
		for (const promise of this.activeExecutions[executionId].postExecutePromises) {
			promise.resolve(fullRunData);
		}

		// Remove from the list of active executions
		delete this.activeExecutions[executionId];
	}

	/**
	 * Forces an execution to stop
	 *
	 * @param {string} executionId The id of the execution to stop
	 * @param {string} timeout String 'timeout' given if stop due to timeout
	 * @returns {(Promise<IRun | undefined>)}
	 * @memberof ActiveExecutions
	 */
	async stopExecution(executionId: string, timeout?: string): Promise<IRun | undefined> {
		if (this.activeExecutions[executionId] === undefined) {
			// There is no execution running with that id
			return;
		}

		// In case something goes wrong make sure that promise gets first
		// returned that it gets then also resolved correctly.
		if (this.activeExecutions[executionId].process !== undefined) {
			// Workflow is running in subprocess
			if (this.activeExecutions[executionId].process!.connected) {
				setTimeout(() => {
					// execute on next event loop tick;
					this.activeExecutions[executionId].process!.send({
						// eslint-disable-next-line @typescript-eslint/prefer-nullish-coalescing
						type: timeout || 'stopExecution',
					});
				}, 1);
			}
		} else {
			// Workflow is running in current process
			this.activeExecutions[executionId].workflowExecution!.cancel();
		}

		// eslint-disable-next-line consistent-return
		return this.getPostExecutePromise(executionId);
	}

	/**
	 * Returns a promise which will resolve with the data of the execution
	 * with the given id
	 *
	 * @param {string} executionId The id of the execution to wait for
	 * @returns {Promise<IRun>}
	 * @memberof ActiveExecutions
	 */
	async getPostExecutePromise(executionId: string): Promise<IRun | undefined> {
		// Create the promise which will be resolved when the execution finished
		const waitPromise = await createDeferredPromise<IRun | undefined>();

		if (this.activeExecutions[executionId] === undefined) {
			throw new Error(`There is no active execution with id "${executionId}".`);
		}

		this.activeExecutions[executionId].postExecutePromises.push(waitPromise);

		return waitPromise.promise();
	}

	/**
	 * Returns all the currently active executions
	 *
	 * @returns {IExecutionsCurrentSummary[]}
	 * @memberof ActiveExecutions
	 */
	getActiveExecutions(): IExecutionsCurrentSummary[] {
		const returnData: IExecutionsCurrentSummary[] = [];

		let data;
		// eslint-disable-next-line no-restricted-syntax
		for (const id of Object.keys(this.activeExecutions)) {
			data = this.activeExecutions[id];
			returnData.push({
				id,
				retryOf: data.executionData.retryOf as string | undefined,
				startedAt: data.startedAt,
				mode: data.executionData.executionMode,
				workflowId: data.executionData.workflowData.id! as string,
			});
		}

		return returnData;
	}
}

let activeExecutionsInstance: ActiveExecutions | undefined;

export function getInstance(): ActiveExecutions {
	if (activeExecutionsInstance === undefined) {
		activeExecutionsInstance = new ActiveExecutions();
	}

	return activeExecutionsInstance;
}