"use client";

import { useActionState } from "react";
import type { HousekeepingResult } from "../../../foundation/contracts";

export interface ContentCommandField {
	readonly name: string;
	readonly label: string;
	readonly type:
		| "identifier"
		| "json"
		| "text"
		| "textarea"
		| "number"
		| "checkbox"
		| "select"
		| "file";
	readonly required?: boolean;
	readonly min?: number;
	readonly max?: number;
	readonly maxLength?: number;
	readonly defaultValue?: string | number | boolean;
	readonly allowUnchanged?: boolean;
	readonly options?: readonly Readonly<{
		value: string | number;
		label: string;
	}>[];
}

export interface ContentCommandSubmission {
	readonly commandId: string;
	readonly input: Readonly<Record<string, unknown>>;
	readonly fields?: readonly ContentCommandField[];
	readonly requiresReason?: boolean;
}

interface ContentCommandFormProps extends ContentCommandSubmission {
	readonly buttonLabel: string;
}

const OMIT_FIELD = Symbol("omit optional Content command field");

function parseField(field: ContentCommandField, formData: FormData): unknown {
	const rawValue = formData.get(field.name);
	if (field.type === "checkbox") {
		if (field.allowUnchanged) {
			if (rawValue === null || rawValue === "") return OMIT_FIELD;
			if (rawValue === "true") return true;
			if (rawValue === "false") return false;
			return OMIT_FIELD;
		}
		return rawValue === "on";
	}
	if (rawValue === null && !field.required) return OMIT_FIELD;
	if (field.type === "file") return rawValue instanceof File ? rawValue : null;
	const raw = String(rawValue ?? "")
		.normalize("NFC")
		.trim();
	if (!raw && !field.required) return OMIT_FIELD;
	if (field.type === "number") {
		if (!raw) return raw;
		const value = Number(raw);
		if (!Number.isSafeInteger(value)) return 0;
		return Math.min(field.max ?? value, Math.max(field.min ?? value, value));
	}
	if (field.type === "select") {
		const selected = field.options?.find(
			(option) => String(option.value) === raw,
		)?.value;
		return selected ?? raw.slice(0, 500);
	}
	if (field.type === "json") {
		try {
			return JSON.parse(raw.slice(0, field.maxLength ?? 20_000));
		} catch {
			return null;
		}
	}
	return raw.slice(
		0,
		field.maxLength ?? (field.type === "textarea" ? 20_000 : 500),
	);
}

const initialState: HousekeepingResult<unknown> | null = null;

export async function submitContentCommandForm(
	configuration: ContentCommandSubmission,
	_previous: HousekeepingResult<unknown> | null,
	formData: FormData,
): Promise<HousekeepingResult<unknown>> {
	const submittedFields = (configuration.fields ?? []).flatMap((field) => {
		const value = parseField(field, formData);
		return value === OMIT_FIELD ? [] : [[field.name, value] as const];
	});
	const input = {
		...configuration.input,
		...Object.fromEntries(submittedFields),
	};
	const reason = String(formData.get("reason") ?? "")
		.normalize("NFC")
		.trim()
		.slice(0, 1000);
	const { executeHousekeepingCommand } = await import(
		"@/actions/housekeeping-command"
	);
	return executeHousekeepingCommand({
		commandId: configuration.commandId,
		input,
		...(configuration.requiresReason ? { reason } : {}),
	});
}

export function ContentCommandForm({
	commandId,
	buttonLabel,
	input,
	fields = [],
	requiresReason = false,
}: ContentCommandFormProps) {
	const [result, submit, pending] = useActionState(
		submitContentCommandForm.bind(null, {
			commandId,
			input,
			fields,
			requiresReason,
		}),
		initialState,
	);
	return (
		<form
			action={submit}
			data-housekeeping-command={commandId}
			className="space-y-3 rounded border border-[var(--admin-border)] p-3"
		>
			{fields.map((field) => (
				<label
					key={field.name}
					htmlFor={`${commandId}-${field.name}`}
					className="block text-sm"
				>
					{field.type === "checkbox" && field.allowUnchanged ? (
						<>
							{field.label}
							<select
								id={`${commandId}-${field.name}`}
								name={field.name}
								defaultValue=""
								className="mt-1 block w-full"
							>
								<option value="">No change</option>
								<option value="true">Enabled</option>
								<option value="false">Disabled</option>
							</select>
						</>
					) : field.type === "checkbox" ? (
						<>
							<input
								id={`${commandId}-${field.name}`}
								name={field.name}
								type="checkbox"
								defaultChecked={field.defaultValue === true}
							/>{" "}
							{field.label}
						</>
					) : field.type === "select" ? (
						<>
							{field.label}
							<select
								id={`${commandId}-${field.name}`}
								name={field.name}
								defaultValue={
									typeof field.defaultValue === "boolean"
										? undefined
										: field.defaultValue
								}
								required={field.required}
								className="mt-1 block w-full"
							>
								{field.required ? null : <option value="">No change</option>}
								{field.options?.map((option) => (
									<option key={option.value} value={option.value}>
										{option.label}
									</option>
								))}
							</select>
						</>
					) : field.type === "textarea" || field.type === "json" ? (
						<>
							{field.label}
							<textarea
								id={`${commandId}-${field.name}`}
								name={field.name}
								required={field.required}
								maxLength={field.maxLength}
								className="mt-1 block w-full"
							/>
						</>
					) : (
						<>
							{field.label}
							<input
								id={`${commandId}-${field.name}`}
								name={field.name}
								type={
									field.type === "number"
										? "number"
										: field.type === "file"
											? "file"
											: "text"
								}
								defaultValue={
									field.type === "file" ||
									typeof field.defaultValue === "boolean"
										? undefined
										: field.defaultValue
								}
								required={field.required}
								min={field.min}
								max={field.max}
								maxLength={field.maxLength}
								className="mt-1 block w-full"
							/>
						</>
					)}
				</label>
			))}
			{requiresReason ? (
				<label htmlFor={`${commandId}-reason`} className="block text-sm">
					Reason
					<textarea
						id={`${commandId}-reason`}
						name="reason"
						required
						maxLength={1000}
						className="mt-1 block w-full"
					/>
				</label>
			) : null}
			<button type="submit" disabled={pending}>
				{pending ? "Working..." : buttonLabel}
			</button>
			{result ? (
				<p role="status" className="text-xs text-[var(--admin-text-muted)]">
					{result.ok ? "Completed" : "Failed"} ({result.correlationId})
				</p>
			) : null}
		</form>
	);
}