/**
 * @file SettingsRow — the settings page's row primitives: a titled card
 * (`SettingsSection`), a label/description | control row (`SettingsRow`), a
 * switch row (`SettingsSwitchRow`) and a segmented radio group
 * (`SettingsSegmented`, arrow keys + one roving tab stop). Rows divide
 * themselves with a hairline, none after the last, so a section is just its
 * rows in order. A string description shows its `backticked` words as code,
 * and a `disabled` row dims its label, so an unavailable control reads as one.
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

import { Switch } from "../Switch";
import type { KeyboardEvent, ReactNode } from "react";

export function SettingsSection({
  id,
  title,
  description,
  children,
}: {
  /** `<section id>` — a deep-link target. */
  id?: string;
  title: ReactNode;
  description?: ReactNode;
  children: ReactNode;
}) {
  return (
    <section id={id} className={id ? "card p-5 scroll-mt-24" : "card p-5"}>
      <h3 className="text-sm font-semibold text-fg-primary">{title}</h3>
      {description && <p className="mt-0.5 text-xs text-fg-muted">{description}</p>}
      <div className="mt-2">{children}</div>
    </section>
  );
}

/** `text` with every `backticked` run drawn as inline code (a command to type). */
export function withCode(text: string): ReactNode {
  const parts = text.split(/`([^`]+)`/);
  if (parts.length === 1) return text;
  return parts.map((p, i) =>
    i % 2 ? (
      <code
        key={i}
        className="whitespace-nowrap rounded border border-border bg-surface-2 px-1 py-px font-mono text-[11px] text-fg-secondary"
      >
        {p}
      </code>
    ) : (
      p
    )
  );
}

export function SettingsRow({
  label,
  description,
  control,
  alignTop = false,
  disabled = false,
  id,
}: {
  label: ReactNode;
  description?: ReactNode;
  control: ReactNode;
  alignTop?: boolean;
  /** The control cannot be used here: the label is dimmed with it. */
  disabled?: boolean;
  /** A deep-link anchor (`#id`) for one row inside a grouped section. */
  id?: string;
}) {
  return (
    <div
      id={id}
      className={`${id ? "scroll-mt-24 " : ""}flex justify-between gap-6 border-b border-border/60 last:border-b-0 ${
        description ? "py-3" : "py-2"
      } ${alignTop ? "items-start" : "items-center"}`}
    >
      <div className="min-w-0">
        <p className={`text-sm ${disabled ? "text-fg-muted" : "text-fg-secondary"}`}>{label}</p>
        {description && (
          <p className="mt-0.5 text-xs leading-relaxed text-fg-muted">
            {typeof description === "string" ? withCode(description) : description}
          </p>
        )}
      </div>
      <div className="shrink-0">{control}</div>
    </div>
  );
}

export function SettingsSwitchRow({
  label,
  description,
  checked,
  onChange,
  disabled = false,
  id,
}: {
  label: string;
  description?: ReactNode;
  checked: boolean;
  onChange: (v: boolean) => void;
  disabled?: boolean;
  id?: string;
}) {
  return (
    <SettingsRow
      id={id}
      label={label}
      description={description}
      disabled={disabled}
      control={<Switch checked={checked} onChange={onChange} label={label} disabled={disabled} />}
    />
  );
}

export function SettingsSegmented<T extends string>({
  options,
  value,
  onChange,
  ariaLabel,
}: {
  options: { value: T; label: ReactNode }[];
  value: T;
  onChange: (v: T) => void;
  ariaLabel?: string;
}) {
  // A radio group's keyboard contract: one tab stop (the checked option), and
  // the arrow keys move the selection — wrapping — and the focus with it.
  const onKeyDown = (e: KeyboardEvent<HTMLDivElement>) => {
    const step = { ArrowRight: 1, ArrowDown: 1, ArrowLeft: -1, ArrowUp: -1 }[e.key];
    if (!step || options.length === 0) return;
    e.preventDefault();
    const at = Math.max(
      0,
      options.findIndex((o) => o.value === value)
    );
    const next = (at + step + options.length) % options.length;
    onChange(options[next]!.value);
    (e.currentTarget.children[next] as HTMLElement | undefined)?.focus();
  };
  return (
    <div
      role="radiogroup"
      aria-label={ariaLabel}
      onKeyDown={onKeyDown}
      className="inline-flex rounded-lg border border-border bg-surface-2 p-0.5"
    >
      {options.map((o, i) => (
        <button
          key={o.value}
          type="button"
          role="radio"
          aria-checked={value === o.value}
          tabIndex={
            value === o.value || (i === 0 && !options.some((x) => x.value === value)) ? 0 : -1
          }
          onClick={() => onChange(o.value)}
          className={`flex items-center gap-1.5 rounded-md px-3 py-1.5 text-xs font-medium transition-colors ${
            value === o.value
              ? "bg-accent/20 text-accent"
              : "text-fg-secondary hover:bg-surface-3 hover:text-fg-primary"
          }`}
        >
          {o.label}
        </button>
      ))}
    </div>
  );
}