'use client'

import { ChevronDown } from 'lucide-react'
import { cn } from '@/lib/utils'
import { HelpPopover } from '@/components/ui/help-popover'

/**
 * The Fönster settings language (founder-approved concept 2026-07-25):
 * flat hairline rows with an uppercase micro-label on the left and the
 * control on the right, section titles in the display serif, groups under
 * eyebrow labels, and every explanation collapsed behind a "?" popover
 * (UI-migration convention 7 applied at row level).
 *
 * All settings sections compose these primitives; do not hand-roll row
 * layouts or inline help paragraphs in section components.
 */

interface SettingsSectionHeaderProps {
  title: string
  /** One quiet line under the title. Longer guidance belongs in row help. */
  intro?: React.ReactNode
  /** Right-aligned header action (e.g. "Förhandsvisa faktura", "Skapa nyckel"). */
  action?: React.ReactNode
  /**
   * Brand mark for a section that represents a third-party channel
   * (WhatsApp today). Sections that are just Accounted settings leave this
   * unset: the serif title carries them, and a decorative icon per tab
   * would turn the settings rail into a sticker album.
   */
  mark?: React.ReactNode
}

export function SettingsSectionHeader({ title, intro, action, mark }: SettingsSectionHeaderProps) {
  return (
    <header>
      <div className="flex items-baseline justify-between gap-4">
        <div className="flex items-center gap-2.5">
          {mark ? <span className="shrink-0 leading-none">{mark}</span> : null}
          <h2 className="font-display text-xl tracking-tight">{title}</h2>
        </div>
        {action ? <div className="flex shrink-0 items-center gap-3">{action}</div> : null}
      </div>
      {intro ? (
        <p className="mt-1 max-w-[56ch] text-xs leading-relaxed text-muted-foreground">{intro}</p>
      ) : null}
    </header>
  )
}

interface SettingsGroupProps {
  label?: string
  /** Group-level help ("?" right after the eyebrow) for guidance that spans the rows. */
  help?: React.ReactNode
  children: React.ReactNode
  className?: string
}

export function SettingsGroup({ label, help, children, className }: SettingsGroupProps) {
  return (
    <section className={cn('pt-8 first:pt-6', className)}>
      {label ? (
        <p className="flex items-center gap-2 px-1 text-[11px] font-medium uppercase tracking-wider text-muted-foreground">
          <span>{label}</span>
          {help ? <HelpPopover className="shrink-0">{help}</HelpPopover> : null}
        </p>
      ) : null}
      <div>{children}</div>
    </section>
  )
}

interface SettingsRowProps {
  label: React.ReactNode
  /** Ties the label to a control; renders a <label> instead of a <span>. */
  htmlFor?: string
  /** Row help content: goes behind a "?" next to the label, never inline. */
  help?: React.ReactNode
  /** 'center' for toggles/selects/chips, 'baseline' for text inputs. */
  align?: 'center' | 'baseline'
  /** Drop the hairline (last row before a fold/reveal). */
  borderless?: boolean
  children: React.ReactNode
  className?: string
}

export function SettingsRow({
  label,
  htmlFor,
  help,
  align = 'center',
  borderless = false,
  children,
  className,
}: SettingsRowProps) {
  const labelClass = 'text-[11px] font-medium uppercase tracking-wider text-muted-foreground'
  return (
    <div
      className={cn(
        'flex flex-col gap-1 px-1 py-3 md:flex-row md:gap-4',
        align === 'center' ? 'md:items-center' : 'md:items-baseline',
        !borderless && 'border-b border-border',
        className,
      )}
    >
      <div className="flex w-full shrink-0 items-center gap-2 md:w-44">
        {htmlFor ? (
          <label htmlFor={htmlFor} className={labelClass}>
            {label}
          </label>
        ) : (
          <span className={labelClass}>{label}</span>
        )}
        {help ? <HelpPopover className="shrink-0">{help}</HelpPopover> : null}
      </div>
      <div className="flex min-w-0 flex-1 flex-wrap items-center gap-x-3 gap-y-1 text-sm">
        {children}
      </div>
    </div>
  )
}

/** Right-aligned slot inside a row (quiet actions, secondary values). */
export function SettingsRowEnd({ children, className }: { children: React.ReactNode; className?: string }) {
  return <div className={cn('ml-auto flex shrink-0 items-center gap-3', className)}>{children}</div>
}

/** Muted secondary text inside a row. */
export function SettingsRowNote({ children, className }: { children: React.ReactNode; className?: string }) {
  return <span className={cn('text-xs text-muted-foreground', className)}>{children}</span>
}

/**
 * Flat text input: borderless with a dashed underline on hover and a solid
 * one on focus. Sized by the row, not by a box.
 */
export function SettingsInput({ className, ...rest }: React.InputHTMLAttributes<HTMLInputElement>) {
  return (
    <input
      {...rest}
      className={cn(
        'min-w-0 flex-1 rounded-none border-0 border-b border-dashed border-transparent bg-transparent px-0 py-1 text-sm text-foreground',
        'placeholder:text-muted-foreground/60 hover:border-border',
        'focus:outline-none focus:border-solid focus:border-foreground/50',
        'disabled:cursor-not-allowed disabled:border-transparent disabled:opacity-60',
        className,
      )}
    />
  )
}

/** Flat textarea sibling of SettingsInput. */
export function SettingsTextarea({ className, ...rest }: React.TextareaHTMLAttributes<HTMLTextAreaElement>) {
  return (
    <textarea
      {...rest}
      className={cn(
        'min-w-0 flex-1 resize-y rounded-none border-0 border-b border-dashed border-transparent bg-transparent px-0 py-1 text-sm text-foreground',
        'placeholder:text-muted-foreground/60 hover:border-border',
        'focus:outline-none focus:border-solid focus:border-foreground/50',
        'disabled:cursor-not-allowed disabled:border-transparent disabled:opacity-60',
        className,
      )}
    />
  )
}

/** Flat native select with a quiet chevron. */
export function SettingsSelect({
  className,
  wrapperClassName,
  children,
  ...rest
}: React.SelectHTMLAttributes<HTMLSelectElement> & { wrapperClassName?: string }) {
  return (
    <span className={cn('relative inline-flex max-w-full items-center', wrapperClassName)}>
      <select
        {...rest}
        className={cn(
          'max-w-full cursor-pointer appearance-none truncate rounded-none border-0 border-b border-dashed border-transparent bg-transparent py-1 pl-0 pr-6 text-sm text-foreground',
          'hover:border-border focus:outline-none focus-visible:border-solid focus-visible:border-foreground/50',
          'disabled:cursor-not-allowed disabled:opacity-60',
          className,
        )}
      >
        {children}
      </select>
      <ChevronDown
        aria-hidden="true"
        className="pointer-events-none absolute right-1 h-3.5 w-3.5 text-muted-foreground"
      />
    </span>
  )
}

interface SettingsRevealProps {
  open: boolean
  /** Indent revealed rows behind a left hairline (gated sub-settings). */
  indent?: boolean
  children: React.ReactNode
}

/** Animated reveal for settings gated behind a toggle (momsreg → momsblock). */
export function SettingsReveal({ open, indent = true, children }: SettingsRevealProps) {
  return (
    <div
      inert={!open}
      className={cn(
        'grid transition-[grid-template-rows] duration-300 motion-reduce:transition-none',
        open ? 'grid-rows-[1fr]' : 'grid-rows-[0fr]',
      )}
    >
      <div className="min-h-0 overflow-hidden">
        <div className={cn(indent && 'ml-3 border-l border-border pl-4')}>{children}</div>
      </div>
    </div>
  )
}

interface SettingsSegProps<T extends string> {
  value: T
  onChange: (value: T) => void
  options: Array<{ value: T; label: React.ReactNode }>
  'aria-label': string
  disabled?: boolean
}

/** Quiet segmented control (theme, language, plan interval, sv/en texts). */
export function SettingsSeg<T extends string>({
  value,
  onChange,
  options,
  'aria-label': ariaLabel,
  disabled,
}: SettingsSegProps<T>) {
  return (
    <div role="group" aria-label={ariaLabel} className="inline-flex items-center gap-1 rounded-lg bg-muted/70 p-1">
      {options.map((o) => (
        <button
          key={o.value}
          type="button"
          disabled={disabled}
          aria-pressed={o.value === value}
          onClick={() => onChange(o.value)}
          className={cn(
            'rounded-sm px-3 py-1 text-xs transition-colors duration-150 disabled:cursor-not-allowed disabled:opacity-60',
            o.value === value
              ? 'border border-border bg-card font-medium text-foreground'
              : 'text-muted-foreground hover:text-foreground',
          )}
        >
          {o.label}
        </button>
      ))}
    </div>
  )
}

/** Terracotta-tinted trailing block for destructive actions. */
export function SettingsDangerZone({ label, children }: { label: string; children: React.ReactNode }) {
  return (
    <section className="mt-10 border-t border-destructive/30 pt-3">
      <p className="px-1 text-[11px] font-medium uppercase tracking-wider text-destructive/80">
        {label}
      </p>
      <div>{children}</div>
    </section>
  )
}