'use client';

import { useState } from 'react';
import { motion } from 'framer-motion';
import { fadeUp } from '@/lib/animations';

const SAMPLES = [
  {
    label: 'p53 (human)',
    seq: `>sp|P04637|P53_HUMAN Cellular tumor antigen p53
MEEPQSDPSVEPPLSQETFSDLWKLLPENNVLSPLPSQAMDDLMLSPDDIEQWFTEDPGP
DEAPRMPEAAPPVAPAPAAPTPAAPAPAPSWPLSSSVPSQKTYPQGLNGTVNLPGRNSFEV
RVCACPHERCTEGRAVKLFSPKELNCEMAQDIINNKFNLNLLPETIPNTIICFVESQPPQGD
SVTTCFSWRGEGNEMYLHTEKEYKALKSTLSEKYMATCLLLSPKKKSLFPEALKLCNQKYS
EEFLLLDEALLSGCFAELACALHLAPAEGRYSGGFNHELYNMMTQQQQHQHHLQMQQHHQQ
HHQQHHQQHHQQQQQQQQQQQQQQQQQH`,
  },
  {
    label: 'Insulin (human)',
    seq: `>sp|P01308|INS_HUMAN Insulin
MALWMRLLPLLALLALWGPDPAAAFVNQHLCGSHLVEALYLVCGERGFFYTPKTRREAED
LQVGQVELGGGPGAGSLQPLALEGSLQKRGIVEQCCTSICSLYQLENYCN`,
  },
];

interface SequenceInputProps {
  value: string;
  onChange: (value: string) => void;
  onSubmit: () => void;
  loading: boolean;
  error?: string | null;
}

export function SequenceInput({ value, onChange, onSubmit, loading, error }: SequenceInputProps) {
  const aaCount = value
    .split('\n')
    .filter((l) => !l.startsWith('>'))
    .join('').length;

  return (
    <motion.div variants={fadeUp} className="bg-white rounded-2xl border border-gray-200 p-6">
      <label className="block text-sm font-medium text-gray-700 mb-2">
        Enter protein sequence (FASTA or plain)
      </label>
      <textarea
        value={value}
        onChange={(e) => onChange(e.target.value)}
        placeholder=">sp|P04637|P53_HUMAN&#10;MEEPQSDPSVEPPLSQETFSDLWKLLPENNVLSPLPSQ..."
        className="w-full h-40 px-4 py-3 rounded-xl border border-gray-300 focus:border-teal-500 focus:ring-2 focus:ring-teal-200 outline-none transition font-mono text-sm text-gray-900 resize-none"
      />
      {error && (
        <p className="mt-2 text-sm text-red-600">{error}</p>
      )}
      <div className="flex items-center justify-between mt-4">
        <div className="flex items-center gap-4">
          {SAMPLES.map((s) => (
            <button
              key={s.label}
              type="button"
              onClick={() => onChange(s.seq)}
              className="text-sm text-teal-600 hover:text-teal-700 underline"
            >
              Load {s.label}
            </button>
          ))}
          <span className="text-xs text-gray-400">
            {value ? `${aaCount} aa` : '0 aa'}
          </span>
        </div>
        <button
          onClick={onSubmit}
          disabled={loading || !value.trim()}
          className="px-6 py-2.5 bg-teal-600 text-white font-medium rounded-xl hover:bg-teal-700 transition disabled:opacity-50"
        >
          {loading ? 'Running pipeline...' : 'Run Pipeline'}
        </button>
      </div>
    </motion.div>
  );
}