import type { ComponentType, ReactNode } from 'react';
import { Inbox } from 'lucide-react';
import { cn } from '@/lib/utils';
import { BrandGlyph } from '@/components/brand/Brand';
import type { BrandGlyphName } from '@/lib/brand';

type Tone = 'neutral' | 'good' | 'warn' | 'danger' | 'info';

const toneClasses: Record<Tone, string> = {
  neutral: 'border-border/75 bg-card/95 text-muted-foreground',
  good: 'border-emerald-500/25 bg-emerald-500/[0.07] text-emerald-700 dark:text-emerald-300',
  warn: 'border-amber-500/30 bg-amber-500/8 text-amber-700 dark:text-amber-300',
  danger: 'border-rose-500/30 bg-rose-500/8 text-rose-700 dark:text-rose-300',
  info: 'border-sky-500/25 bg-sky-500/[0.07] text-sky-700 dark:text-sky-300',
};

const dotClasses: Record<Tone, string> = {
  neutral: 'bg-muted-foreground/55',
  good: 'bg-emerald-500',
  warn: 'bg-amber-500',
  danger: 'bg-rose-500',
  info: 'bg-sky-500',
};

interface PageHeaderProps {
  eyebrow?: ReactNode;
  title: ReactNode;
  description?: ReactNode;
  glyph?: BrandGlyphName;
  icon?: ComponentType<{ className?: string }>;
  actions?: ReactNode;
  meta?: ReactNode;
  className?: string;
}

export function PageHeader({
  eyebrow,
  title,
  description,
  glyph,
  icon: Icon,
  actions,
  meta,
  className,
}: PageHeaderProps) {
  return (
    <section
      className={cn('flex flex-col gap-4 sm:flex-row sm:items-end sm:justify-between', className)}
    >
      <div className="flex min-w-0 items-start gap-3">
        {glyph && <BrandGlyph name={glyph} className="mt-0.5 hidden sm:inline-block" />}
        {Icon && !glyph && (
          <span className="mt-0.5 hidden h-10 w-10 shrink-0 place-items-center rounded-xl border border-primary/20 bg-primary/8 text-primary shadow-sm shadow-primary/10 sm:grid">
            <Icon className="h-5 w-5" />
          </span>
        )}
        <div className="min-w-0">
          {eyebrow && (
            <p className="mb-1 text-[11px] font-semibold uppercase tracking-[0.18em] text-muted-foreground">
              {eyebrow}
            </p>
          )}
          <h1 className="text-balance text-2xl font-semibold tracking-tight text-foreground sm:text-3xl">
            {title}
          </h1>
          {description && (
            <p className="mt-1 max-w-2xl text-sm leading-6 text-muted-foreground">{description}</p>
          )}
          {meta && <div className="mt-2 text-xs text-muted-foreground">{meta}</div>}
        </div>
      </div>
      {actions && <div className="flex flex-wrap items-center gap-2 sm:justify-end">{actions}</div>}
    </section>
  );
}

export function SectionSurface({
  children,
  className,
  tone = 'neutral',
}: {
  children: ReactNode;
  className?: string;
  tone?: Tone;
}) {
  return (
    <section className={cn('surface-premium', tone !== 'neutral' && toneClasses[tone], className)}>
      {children}
    </section>
  );
}

export function StatusDot({
  tone = 'neutral',
  pulse = false,
  className,
}: {
  tone?: Tone;
  pulse?: boolean;
  className?: string;
}) {
  return (
    <span className={cn('relative inline-flex h-2.5 w-2.5 shrink-0', className)} aria-hidden="true">
      {pulse && (
        <span
          className={cn(
            'absolute inline-flex h-full w-full animate-ping rounded-full opacity-40',
            dotClasses[tone],
          )}
        />
      )}
      <span className={cn('relative inline-flex h-2.5 w-2.5 rounded-full', dotClasses[tone])} />
    </span>
  );
}

export function MetricCard({
  label,
  value,
  hint,
  icon: Icon,
  tone = 'neutral',
  action,
  className,
}: {
  label: ReactNode;
  value: ReactNode;
  hint?: ReactNode;
  icon?: ComponentType<{ className?: string }>;
  tone?: Tone;
  action?: ReactNode;
  className?: string;
}) {
  return (
    <div className={cn('metric-card', tone !== 'neutral' && toneClasses[tone], className)}>
      <div className="flex items-start justify-between gap-3">
        <div className="flex min-w-0 items-center gap-2">
          {Icon && (
            <span className="grid h-7 w-7 shrink-0 place-items-center rounded-lg border border-current/15 bg-current/8 text-current">
              <Icon className="h-3.5 w-3.5 opacity-90" />
            </span>
          )}
          <p className="truncate text-[11px] font-semibold uppercase tracking-[0.16em] text-muted-foreground">
            {label}
          </p>
        </div>
        {action}
      </div>
      <div className="metric-value mt-4 text-2xl leading-none sm:text-[1.72rem]">{value}</div>
      {hint && <p className="mt-2 text-xs leading-5 text-muted-foreground">{hint}</p>}
    </div>
  );
}

export function EmptyState({
  title,
  description,
  icon: Icon = Inbox,
  action,
  className,
}: {
  title: ReactNode;
  description?: ReactNode;
  icon?: ComponentType<{ className?: string }>;
  action?: ReactNode;
  className?: string;
}) {
  return (
    <div
      className={cn(
        'surface-premium flex flex-col items-center justify-center px-6 py-12 text-center',
        className,
      )}
    >
      <span className="grid h-11 w-11 place-items-center rounded-xl border border-border/70 bg-muted/35 text-muted-foreground">
        <Icon className="h-5 w-5" />
      </span>
      <h2 className="mt-4 text-base font-semibold text-foreground">{title}</h2>
      {description && (
        <p className="mt-1 max-w-md text-sm leading-6 text-muted-foreground">{description}</p>
      )}
      {action && <div className="mt-4">{action}</div>}
    </div>
  );
}