import React, { useEffect, useState } from 'react';
import type { HttpHeader } from '../lib/models';
import { IconButton } from './IconButton';
import { Input } from './Input';
import { VStack } from './Stacks';

type PairWithId = { header: Partial<HttpHeader>; id: string };

export function HeaderEditor() {
  const newPair = () => {
    return { header: { name: '', value: '' }, id: Math.random().toString() };
  };

  const [pairs, setPairs] = useState<PairWithId[]>([newPair()]);

  const handleChangeHeader = (pair: PairWithId) => {
    setPairs((pairs) =>
      pairs.map((p) =>
        pair.id !== p.id ? p : { id: p.id, header: { ...p.header, ...pair.header } },
      ),
    );
  };

  useEffect(() => {
    const lastPair = pairs[pairs.length - 1];
    if (lastPair === undefined) {
      setPairs([newPair()]);
      return;
    }

    if (lastPair.header.name !== '' || lastPair.header.value !== '') {
      setPairs((pairs) => [...pairs, newPair()]);
    }
  }, [pairs]);

  const handleDelete = (pair: PairWithId) => {
    setPairs((headers) => headers.filter((p) => p.id !== pair.id));
  };

  return (
    <VStack space={2}>
      {pairs.map((p, i) => (
        <FormRow
          key={p.id}
          pair={p}
          onChange={handleChangeHeader}
          onDelete={i < pairs.length - 1 ? handleDelete : undefined}
        />
      ))}
    </VStack>
  );
}

function FormRow({
  autoFocus,
  pair,
  onChange,
  onDelete,
}: {
  autoFocus?: boolean;
  pair: PairWithId;
  onChange: (pair: PairWithId) => void;
  onDelete?: (pair: PairWithId) => void;
}) {
  return (
    <div className="grid grid-cols-[1fr_1fr_2.5rem] grid-rows-1 gap-2 items-center">
      <Input
        hideLabel
        autoFocus={autoFocus}
        useEditor={{ useTemplating: true }}
        name="name"
        label="Name"
        placeholder="name"
        defaultValue={pair.header.name}
        onChange={(name) =>
          onChange({
            id: pair.id,
            header: { name },
          })
        }
      />
      <Input
        hideLabel
        name="value"
        label="Value"
        useEditor={{ useTemplating: true }}
        placeholder="value"
        defaultValue={pair.header.value}
        onChange={(value) =>
          onChange({
            id: pair.id,
            header: { value },
          })
        }
      />
      {onDelete && <IconButton icon="trash" onClick={() => onDelete(pair)} className="w-auto" />}
    </div>
  );
}