import { useEffect, useState } from 'react';
import { FLEET_GROUP_COLORS, normalizeGroupColor } from '../../help/fleetGroups';
import './CreateGroupModal.css';

interface Props {
  open: boolean;
  agentCount: number;
  onClose: () => void;
  onCreate: (name: string, color: string) => void;
}

export default function CreateGroupModal({ open, agentCount, onClose, onCreate }: Props) {
  const [name, setName] = useState('');
  const [color, setColor] = useState<string>(FLEET_GROUP_COLORS[0]);

  useEffect(() => {
    if (open) {
      setName('');
      setColor(FLEET_GROUP_COLORS[groupsColorIndex(agentCount) % FLEET_GROUP_COLORS.length]);
    }
  }, [open, agentCount]);

  if (!open || agentCount < 1) return null;

  const submit = (e: React.FormEvent) => {
    e.preventDefault();
    const trimmed = name.trim();
    if (!trimmed) return;
    onCreate(trimmed, normalizeGroupColor(color));
    onClose();
  };

  return (
    <div className="fleet-group-modal-backdrop" role="presentation" onClick={onClose}>
      <div
        className="fleet-group-modal card"
        role="dialog"
        aria-labelledby="fleet-group-modal-title"
        onClick={(e) => e.stopPropagation()}
      >
        <h2 id="fleet-group-modal-title" className="font-display">Create group</h2>
        <p className="form-hint">
          Saves {agentCount} selected machine{agentCount === 1 ? '' : 's'} — usable in Fleet Roster and Crucible.
        </p>
        <form onSubmit={submit}>
          <label className="label" htmlFor="fleet-group-name">Group name</label>
          <input
            id="fleet-group-name"
            className="input"
            value={name}
            onChange={(e) => setName(e.target.value)}
            placeholder="e.g. Living room PCs"
            autoFocus
            maxLength={64}
          />

          <p className="label" style={{ marginTop: '1rem' }}>Group color</p>
          <div className="fleet-group-color-grid">
            {FLEET_GROUP_COLORS.map((c) => (
              <button
                key={c}
                type="button"
                className={`fleet-group-swatch ${color === c ? 'selected' : ''}`}
                style={{ background: c }}
                title={c}
                aria-label={`Color ${c}`}
                onClick={() => setColor(c)}
              />
            ))}
          </div>
          <div className="fleet-group-custom-color">
            <input
              type="color"
              value={normalizeGroupColor(color)}
              onChange={(e) => setColor(e.target.value)}
              aria-label="Custom color"
            />
            <span className="font-tech">{normalizeGroupColor(color)}</span>
          </div>

          <div className="fleet-group-modal-actions">
            <button type="button" className="btn btn-outline" onClick={onClose}>
              Cancel
            </button>
            <button type="submit" className="btn btn-primary" disabled={!name.trim()}>
              Create group
            </button>
          </div>
        </form>
      </div>
    </div>
  );
}

function groupsColorIndex(n: number): number {
  return Math.abs(n) % FLEET_GROUP_COLORS.length;
}
