import { is, predicates } from "@sealcode/ts-predicates";
import { Context } from "koa";
import { Checkbox } from "../controls/checkbox.js";
import { FormDataValue } from "../form-types.js";
import { FieldParseResult, FormField } from "./field.js";
import { FormControlContext } from "../controls/form-control.js";

const truthy = ["true", "on", "yes", "1"];
const falsy = ["false", "off", "no", "0"];

export class Boolean<Required extends boolean> extends FormField<
	Required,
	boolean,
	Checkbox
> {
	predicate = predicates.boolean;
	constructor(
		required: Required,
		public error_message: string = ""
	) {
		super(required);
	}

	public async isValueValid(
		_: Context,
		value: boolean
	): Promise<{ valid: boolean; message: string }> {
		if (this.required && !value) {
			return { valid: false, message: this.error_message };
		}
		return { valid: true, message: "" };
	}

	async parse(
		_: Context,
		value: FormDataValue
	): Promise<FieldParseResult<boolean>> {
		if (is(value, predicates.boolean)) {
			return { parsable: true, parsed_value: value, error: null };
		} else if (
			is(value, predicates.string) &&
			[...truthy, ...falsy].includes(value)
		) {
			return {
				parsable: true,
				parsed_value: truthy.includes(value),
				error: null,
			};
		} else if (is(value, predicates.undefined)) {
			return {
				parsable: true,
				parsed_value: false,
				error: null,
			};
		} else if (value === null || value === "") {
			return { parsable: true, parsed_value: false, error: null };
		} else {
			return {
				parsable: false,
				parsed_value: null,
				error: "Please enter a boolean",
			};
		}
	}

	public getEmptyValue(): boolean {
		return false;
	}

	public getControl(): Checkbox {
		return new Checkbox(this, { label: this.label || this.name });
	}

	async getSealiousCreateValue(fctx: FormControlContext): Promise<boolean> {
		const { parsed } = await this.getParsedValue(
			fctx.ctx,
			fctx.data.raw_values
		);
		return !!parsed;
	}

	async sealiousValueToForm(
		_: Context,
		value: boolean | null
	): Promise<FormDataValue> {
		return value ? "true" : "false";
	}
}