import { Data_Validation_Failed, Data_Coercion_Failed } from '@efforting.tech/errors';

export class Field_Configuration {
	constructor(name, validation_function=null, coercion_function=null, expected_description=undefined) {
		Object.assign(this, { name, validation_function, coercion_function, expected_description });
	}

	check_validation(value) {
		const { validation_function } = this;
		return !validation_function || validation_function(value);
	}

	validate(value, target=undefined) {
		const { validation_function, name, expected_description } = this;
		if (!this.check_validation(value)) {
			throw new Data_Validation_Failed({
				name, validation_function, value,
				target, expected_description,
			});
		}
	}

	coerce(value, target=undefined) {
		const { coercion_function, name, expected_description } = this;
		try {
			return coercion_function ? coercion_function(value) : value;
		} catch (e) {
			throw new Data_Coercion_Failed({
				name, coercion_function, value,
				target, expected_description,
				upstream_error: e,
			})
		}
	}

	load(value, target=undefined) {
		const coerced_value = this.coerce(value, target);
		this.validate(coerced_value, target);
		return coerced_value;
	}


}