'use client'

import { motion } from 'framer-motion'
import { useState, useEffect } from 'react'
import { FileCheck, Check } from 'lucide-react'

function resolveHsl(cssVar: string): string {
  if (typeof window === 'undefined') return 'transparent'
  const value = getComputedStyle(document.documentElement).getPropertyValue(cssVar).trim()
  return value ? `hsl(${value})` : 'transparent'
}

export function PolicyDemoVisual() {
  const [phase, setPhase] = useState(0)
  const [colors, setColors] = useState({ burgundy: '#993350', teal: '#2e6b6a', border: '#27272a', mutedFg: '#aba49d' })

  useEffect(() => {
    setColors({
      burgundy: resolveHsl('--burgundy'),
      teal: resolveHsl('--teal'),
      border: resolveHsl('--border'),
      mutedFg: resolveHsl('--muted-foreground'),
    })
  }, [])

  useEffect(() => {
    const interval = setInterval(() => {
      setPhase(p => (p + 1) % 2)
    }, 3000)
    return () => clearInterval(interval)
  }, [])

  return (
    <div className="relative h-full bg-gradient-to-br from-background via-background to-[hsl(var(--burgundy))]/5 rounded-xl p-4 overflow-hidden">
      {/* Document Header */}
      <div className="mb-3 flex items-center justify-between">
        <div className="flex items-center gap-2">
          <FileCheck className="h-4 w-4 text-[hsl(var(--burgundy))]" />
          <span className="text-xs font-bold text-foreground">Terms of Service</span>
        </div>
        <motion.div
          className="px-2 py-0.5 rounded-full border text-[9px] font-bold"
          animate={{
            borderColor: phase === 1 ? colors.teal : colors.border,
            backgroundColor: phase === 1 ? `${colors.teal}1a` : 'rgba(0,0,0,0)',
            color: phase === 1 ? colors.teal : colors.mutedFg
          }}
          transition={{ duration: 0.5 }}
        >
          {phase === 0 ? 'v2.1' : 'v2.2'}
        </motion.div>
      </div>

      {/* Document Content */}
      <motion.div
        className="space-y-2 p-3 rounded-lg border border-zinc-200 dark:border-zinc-800 bg-white dark:bg-zinc-950 overflow-hidden"
        animate={{
          borderColor: phase === 1 ? colors.burgundy : colors.border,
          boxShadow: phase === 1
            ? `0 0 20px ${colors.burgundy}33`
            : '0 1px 3px rgba(0,0,0,0.2)'
        }}
        transition={{ duration: 0.5 }}
      >
        {/* Section 4.2 */}
        <div className="space-y-1.5">
          <div className="text-[10px] font-bold text-zinc-300">
            Section 4.2 - Data Retention
          </div>

          {/* Text Lines */}
          <div className="space-y-1 text-[9px] text-zinc-500 leading-relaxed">
            <p>We will retain your personal data for</p>

            {/* Changing text */}
            <motion.div
              className="relative rounded"
              layout
            >
              <motion.p
                animate={{
                  backgroundColor: phase === 1 ? `${colors.burgundy}1a` : 'rgba(0,0,0,0)',
                  paddingLeft: phase === 1 ? '4px' : '0px',
                  paddingRight: phase === 1 ? '4px' : '0px',
                  color: phase === 1 ? colors.burgundy : 'inherit',
                  fontWeight: phase === 1 ? 600 : 400
                }}
                transition={{ duration: 0.4 }}
                className="relative inline-block rounded"
              >
                {phase === 0 ? (
                  'as long as necessary to fulfill purposes'
                ) : (
                  <motion.span
                    initial={{ opacity: 0, y: -5 }}
                    animate={{ opacity: 1, y: 0 }}
                    transition={{ duration: 0.3 }}
                  >
                    a minimum of 90 days after account deletion
                  </motion.span>
                )}
              </motion.p>

              {/* Change highlight indicator */}
              {phase === 1 && (
                <motion.div
                  initial={{ scaleX: 0 }}
                  animate={{ scaleX: 1 }}
                  transition={{ duration: 0.4 }}
                  className="absolute -left-1 top-0 bottom-0 w-0.5 bg-[hsl(var(--burgundy))] rounded-full origin-left"
                />
              )}
            </motion.div>

            <p>outlined in our Privacy Policy.</p>
          </div>
        </div>

        {/* Diff Stats */}
        {phase === 1 && (
          <motion.div
            initial={{ opacity: 0, height: 0 }}
            animate={{ opacity: 1, height: 'auto' }}
            transition={{ delay: 0.3 }}
            className="pt-2 border-t border-zinc-800 flex items-center justify-between"
          >
            <div className="flex items-center gap-3 text-[8px] text-zinc-500">
              <span className="flex items-center gap-1">
                <span className="w-2 h-2 rounded bg-green-500/20 border border-green-500" />
                +18 words
              </span>
              <span className="flex items-center gap-1">
                <span className="w-2 h-2 rounded bg-[hsl(var(--burgundy))]/20 border border-[hsl(var(--burgundy))]" />
                -7 words
              </span>
            </div>
          </motion.div>
        )}
      </motion.div>

      {/* Audit Trail Badge */}
      {phase === 1 && (
        <motion.div
          initial={{ opacity: 0, y: 5, scale: 0.9 }}
          animate={{ opacity: 1, y: 0, scale: 1 }}
          transition={{ delay: 0.5 }}
          className="mt-3 flex items-center gap-2 p-2 rounded-lg bg-[hsl(var(--burgundy))]/10 border border-[hsl(var(--burgundy))]/30"
        >
          <div className="flex-shrink-0 flex items-center justify-center w-5 h-5 rounded-full bg-[hsl(var(--burgundy))] text-white">
            <Check className="h-3 w-3" strokeWidth={3} />
          </div>
          <div className="flex-1">
            <div className="text-[9px] font-bold text-[hsl(var(--burgundy))]">
              Audit trail saved
            </div>
            <div className="text-[8px] text-[hsl(var(--burgundy))]/80">
              Snapshot archived for compliance
            </div>
          </div>
        </motion.div>
      )}
    </div>
  )
}