import { DATA_TABLE_SYSTEM_COLUMN_TYPE_MAP, NodeOperationError } from 'n8n-workflow';
import type {
	DataTableFilter,
	DataTableRowReturn,
	IDataTableProjectService,
	IDisplayOptions,
	IExecuteFunctions,
	INodeProperties,
	DataTableColumnType,
} from 'n8n-workflow';

import { ALL_CONDITIONS, ANY_CONDITION, ROWS_LIMIT_DEFAULT, type FilterType } from './constants';
import { DATA_TABLE_ID_FIELD } from './fields';
import { buildGetManyFilter, isFieldArray, isMatchType, getDataTableProxyExecute } from './utils';

/**
 * Recursively converts Date objects to ISO strings in an object
 * This ensures that all output data is JSON-compatible
 */
function convertDatesToIsoStrings<T>(obj: T): T {
	if (obj === null || obj === undefined) {
		return obj;
	}

	if (obj instanceof Date) {
		return obj.toISOString() as T;
	}

	if (Array.isArray(obj)) {
		return obj.map(convertDatesToIsoStrings) as T;
	}

	if (typeof obj === 'object') {
		const converted: Record<string, unknown> = {};
		for (const [key, value] of Object.entries(obj)) {
			converted[key] = convertDatesToIsoStrings(value);
		}
		return converted as T;
	}

	return obj;
}

export function getSelectFields(
	displayOptions: IDisplayOptions,
	requireCondition = false,
	skipOperator = false,
): INodeProperties[] {
	return [
		{
			displayName: 'Must Match',
			name: 'matchType',
			type: 'options',
			options: [
				{
					name: 'Any Condition',
					value: ANY_CONDITION,
				},
				{
					name: 'All Conditions',
					value: ALL_CONDITIONS,
				},
			] satisfies Array<{ value: FilterType; name: string }>,
			displayOptions,
			default: ANY_CONDITION,
		},
		{
			displayName: 'Conditions',
			name: 'filters',
			type: 'fixedCollection',
			typeOptions: {
				multipleValues: true,
				minRequiredFields: requireCondition ? 1 : 0,
			},
			displayOptions,
			default: {},
			placeholder: 'Add Condition',
			options: [
				{
					displayName: 'Conditions',
					name: 'conditions',
					values: [
						{
							// eslint-disable-next-line n8n-nodes-base/node-param-display-name-wrong-for-dynamic-options
							displayName: 'Column',
							name: 'keyName',
							type: 'options',
							// eslint-disable-next-line n8n-nodes-base/node-param-description-wrong-for-dynamic-options
							description:
								'Choose from the list, or specify using an <a href="https://docs.n8n.io/code/expressions/">expression</a>',
							typeOptions: {
								loadOptionsDependsOn: [`${DATA_TABLE_ID_FIELD}.value`],
								loadOptionsMethod: 'getDataTableColumns',
							},
							default: 'id',
						},
						{
							// eslint-disable-next-line n8n-nodes-base/node-param-display-name-wrong-for-dynamic-options
							displayName: 'Condition',
							name: 'condition',
							// eslint-disable-next-line n8n-nodes-base/node-param-description-missing-from-dynamic-options
							type: 'options',
							typeOptions: {
								loadOptionsDependsOn: ['&keyName'],
								loadOptionsMethod: 'getConditionsForColumn',
							},
							default: 'eq',
							displayOptions: skipOperator
								? {
										show: { '@version': [{ _cnd: { lt: 0 } }] },
									}
								: undefined,
						},
						{
							displayName: 'Value',
							name: 'keyValue',
							type: 'string',
							default: '',
							displayOptions: {
								hide: {
									condition: ['isEmpty', 'isNotEmpty', 'isTrue', 'isFalse'],
								},
							},
						},
					],
				},
			],
			description: 'Filter to decide which rows get',
		},
	];
}

export async function getSelectFilter(
	ctx: IExecuteFunctions,
	index: number,
): Promise<DataTableFilter> {
	const fields = ctx.getNodeParameter('filters.conditions', index, []);
	const matchType = ctx.getNodeParameter('matchType', index, ANY_CONDITION);
	const node = ctx.getNode();

	if (!isMatchType(matchType)) {
		throw new NodeOperationError(node, 'unexpected match type');
	}
	if (!isFieldArray(fields)) {
		throw new NodeOperationError(node, 'unexpected fields input');
	}

	// Validate filter conditions against current table schema
	let allColumnsWithTypes: Record<string, DataTableColumnType> = DATA_TABLE_SYSTEM_COLUMN_TYPE_MAP;

	if (fields.length > 0) {
		const dataTableProxy = await getDataTableProxyExecute(ctx, index);
		const availableColumns = await dataTableProxy.getColumns();

		// Add system columns with their types
		allColumnsWithTypes = {
			...DATA_TABLE_SYSTEM_COLUMN_TYPE_MAP,
			...Object.fromEntries(availableColumns.map((col) => [col.name, col.type])),
		};

		const invalidConditions = fields.filter((field) => !allColumnsWithTypes[field.keyName]);

		if (invalidConditions.length > 0) {
			const invalidColumnNames = invalidConditions.map((c) => c.keyName).join(', ');
			throw new NodeOperationError(
				node,
				`Filter validation failed: Column(s) "${invalidColumnNames}" do not exist in the selected table. ` +
					'This often happens when switching between tables with different schemas. ' +
					'Please update your filter conditions.',
			);
		}
	}

	return buildGetManyFilter(fields, matchType, allColumnsWithTypes, node);
}

export async function executeSelectMany(
	ctx: IExecuteFunctions,
	index: number,
	dataTableProxy: IDataTableProjectService,
	rejectEmpty = false,
	limit?: number,
	sortBy?: [string, 'ASC' | 'DESC'],
): Promise<Array<{ json: DataTableRowReturn }>> {
	const filter = await getSelectFilter(ctx, index);

	if (rejectEmpty && filter.filters.length === 0) {
		throw new NodeOperationError(ctx.getNode(), 'At least one condition is required');
	}

	const PAGE_SIZE = 1000;
	const result: Array<{ json: DataTableRowReturn }> = [];

	const returnAll = ctx.getNodeParameter('returnAll', index, false);
	limit = limit ?? (!returnAll ? ctx.getNodeParameter('limit', index, ROWS_LIMIT_DEFAULT) : 0);

	const nodeVersion = ctx.getNode().typeVersion;
	const shouldConvertDates = nodeVersion >= 1.1;

	let expectedTotal: number | undefined;
	let skip = 0;
	let take = PAGE_SIZE;

	while (true) {
		const { data, count } = await dataTableProxy.getManyRowsAndCount({
			skip,
			take: limit ? Math.min(take, limit - result.length) : take,
			filter,
			sortBy,
		});
		const wrapped = data.map((json) => ({
			json: shouldConvertDates ? convertDatesToIsoStrings(json) : json,
		}));

		// Fast path: everything fits in a single page
		if (skip === 0 && count === data.length) {
			return wrapped;
		}

		// Ensure the total doesn't change mid-pagination
		if (expectedTotal !== undefined && count !== expectedTotal) {
			throw new NodeOperationError(
				ctx.getNode(),
				'synchronization error: result count changed during pagination',
			);
		}
		expectedTotal = count;

		result.push.apply(result, wrapped);

		// Stop if we've hit the limit
		if (limit && result.length >= limit) break;

		// Stop if we've collected everything
		if (result.length >= count) break;

		skip = result.length;
		take = Math.min(PAGE_SIZE, count - result.length);
	}

	return result;
}