import { NamingStrategyInterface } from './NamingStrategyInterface';
import { RandomGenerator } from '../util/RandomGenerator';
import { camelCase, snakeCase, titleCase } from '../util/StringUtils';
import { Table } from '../schema-builder/table/Table';

/**
 * Naming strategy that is used by default.
 */
export class DefaultNamingStrategy implements NamingStrategyInterface {
	protected getTableName(tableOrName: Table | string): string {
		if (typeof tableOrName !== 'string') {
			tableOrName = tableOrName.name;
		}

		return tableOrName.split('.').pop()!;
	}
	/**
	 * Normalizes table name.
	 *
	 * @param targetName Name of the target entity that can be used to generate a table name.
	 * @param userSpecifiedName For example if user specified a table name in a decorator, e.g. @Entity("name")
	 */
	tableName(targetName: string, userSpecifiedName: string | undefined): string {
		return userSpecifiedName ? userSpecifiedName : snakeCase(targetName);
	}

	/**
	 * Creates a table name for a junction table of a closure table.
	 *
	 * @param originalClosureTableName Name of the closure table which owns this junction table.
	 */
	closureJunctionTableName(originalClosureTableName: string): string {
		return originalClosureTableName + '_closure';
	}

	columnName(propertyName: string, customName: string, embeddedPrefixes: string[]): string {
		const name = customName || propertyName;

		if (embeddedPrefixes.length) return camelCase(embeddedPrefixes.join('_')) + titleCase(name);

		return name;
	}

	relationName(propertyName: string): string {
		return propertyName;
	}

	primaryKeyName(tableOrName: Table | string, columnNames: string[]): string {
		// sort incoming column names to avoid issue when ["id", "name"] and ["name", "id"] arrays
		const clonedColumnNames = [...columnNames];
		clonedColumnNames.sort();
		const tableName = this.getTableName(tableOrName);
		const replacedTableName = tableName.replace('.', '_');
		const key = `${replacedTableName}_${clonedColumnNames.join('_')}`;
		return 'PK_' + RandomGenerator.sha1(key).substr(0, 27);
	}

	uniqueConstraintName(tableOrName: Table | string, columnNames: string[]): string {
		// sort incoming column names to avoid issue when ["id", "name"] and ["name", "id"] arrays
		const clonedColumnNames = [...columnNames];
		clonedColumnNames.sort();
		const tableName = this.getTableName(tableOrName);
		const replacedTableName = tableName.replace('.', '_');
		const key = `${replacedTableName}_${clonedColumnNames.join('_')}`;
		return 'UQ_' + RandomGenerator.sha1(key).substr(0, 27);
	}

	relationConstraintName(
		tableOrName: Table | string,
		columnNames: string[],
		where?: string,
	): string {
		// sort incoming column names to avoid issue when ["id", "name"] and ["name", "id"] arrays
		const clonedColumnNames = [...columnNames];
		clonedColumnNames.sort();
		const tableName = this.getTableName(tableOrName);
		const replacedTableName = tableName.replace('.', '_');
		let key = `${replacedTableName}_${clonedColumnNames.join('_')}`;
		if (where) key += `_${where}`;

		return 'REL_' + RandomGenerator.sha1(key).substr(0, 26);
	}

	defaultConstraintName(tableOrName: Table | string, columnName: string): string {
		const tableName = this.getTableName(tableOrName);
		const replacedTableName = tableName.replace('.', '_');
		const key = `${replacedTableName}_${columnName}`;
		return 'DF_' + RandomGenerator.sha1(key).substr(0, 27);
	}

	foreignKeyName(
		tableOrName: Table | string,
		columnNames: string[],
		_referencedTablePath?: string,
		_referencedColumnNames?: string[],
	): string {
		// sort incoming column names to avoid issue when ["id", "name"] and ["name", "id"] arrays
		const clonedColumnNames = [...columnNames];
		clonedColumnNames.sort();
		const tableName = this.getTableName(tableOrName);
		const replacedTableName = tableName.replace('.', '_');
		const key = `${replacedTableName}_${clonedColumnNames.join('_')}`;
		return 'FK_' + RandomGenerator.sha1(key).substr(0, 27);
	}

	indexName(tableOrName: Table | string, columnNames: string[], where?: string): string {
		// sort incoming column names to avoid issue when ["id", "name"] and ["name", "id"] arrays
		const clonedColumnNames = [...columnNames];
		clonedColumnNames.sort();
		const tableName = this.getTableName(tableOrName);
		const replacedTableName = tableName.replace('.', '_');
		let key = `${replacedTableName}_${clonedColumnNames.join('_')}`;
		if (where) key += `_${where}`;

		return 'IDX_' + RandomGenerator.sha1(key).substr(0, 26);
	}

	checkConstraintName(tableOrName: Table | string, expression: string, isEnum?: boolean): string {
		const tableName = this.getTableName(tableOrName);
		const replacedTableName = tableName.replace('.', '_');
		const key = `${replacedTableName}_${expression}`;
		const name = 'CHK_' + RandomGenerator.sha1(key).substr(0, 26);
		return isEnum ? `${name}_ENUM` : name;
	}

	exclusionConstraintName(tableOrName: Table | string, expression: string): string {
		const tableName = this.getTableName(tableOrName);
		const replacedTableName = tableName.replace('.', '_');
		const key = `${replacedTableName}_${expression}`;
		return 'XCL_' + RandomGenerator.sha1(key).substr(0, 26);
	}

	joinColumnName(relationName: string, referencedColumnName: string): string {
		return camelCase(relationName + '_' + referencedColumnName);
	}

	joinTableName(
		firstTableName: string,
		secondTableName: string,
		firstPropertyName: string,
		secondPropertyName: string,
	): string {
		return snakeCase(
			firstTableName + '_' + firstPropertyName.replace(/\./gi, '_') + '_' + secondTableName,
		);
	}

	joinTableColumnDuplicationPrefix(columnName: string, index: number): string {
		return columnName + '_' + index;
	}

	joinTableColumnName(tableName: string, propertyName: string, columnName?: string): string {
		return camelCase(tableName + '_' + (columnName ? columnName : propertyName));
	}

	joinTableInverseColumnName(tableName: string, propertyName: string, columnName?: string): string {
		return this.joinTableColumnName(tableName, propertyName, columnName);
	}

	/**
	 * Adds globally set prefix to the table name.
	 * This method is executed no matter if prefix was set or not.
	 * Table name is either user's given table name, either name generated from entity target.
	 * Note that table name comes here already normalized by #tableName method.
	 */
	prefixTableName(prefix: string, tableName: string): string {
		return prefix + tableName;
	}

	nestedSetColumnNames = { left: 'nsleft', right: 'nsright' };
	materializedPathColumnName = 'mpath';
}