import React, { useState } from "react";

const checkLinksAreOk = (links, listOfElements) => {
  let linkSourceNames = links.map((link) => link.source.name);
  let linkTargetNames = links.map((link) => link.target.name);
  let allLinkNames = [...linkSourceNames, ...linkTargetNames];
  let uniqueNames = [...new Set(allLinkNames)];

  let listOfElementNames = listOfElements.map((element) => element.name);
  let anyInvalidNames = uniqueNames.indexOf(
    (name) => !listOfElementNames.includes(name)
  );
  let anyElementsWithoutDistances = links.indexOf(
    (link) => !link.distance && link.distance != 0
  );
  if (anyInvalidNames == -1 && anyElementsWithoutDistances == -1) {
    return true;
  } else {
    return false;
  }
};

export function ComparisonsChanger({
  setLinks,
  listOfElements,
  show,
  moveToNextStep,
}) {
  let [value, setValue] = useState(``);
  const [displayingDoneMessage, setDisplayingDoneMessage] = useState(false);
  const [displayingDoneMessageTimer, setDisplayingDoneMessageTimer] =
    useState(null);

  let handleTextChange = (event) => {
    setValue(event.target.value);
  };

  let handleSubmitInner = (event) => {
    clearTimeout(displayingDoneMessageTimer);
    event.preventDefault();
    try {
      let newData = JSON.parse(value);
      // setLinks
      // newData
      if (checkLinksAreOk(newData, listOfElements)) {
        setLinks(newData);
        moveToNextStep({
          listOfElements,
          whileChangingStuff: true,
          newLinksFromChangingStuff: newData,
        });
        setDisplayingDoneMessage(true);
        let timer = setTimeout(() => setDisplayingDoneMessage(false), 3000);
        setDisplayingDoneMessageTimer(timer);
      } else {
        throw Error("Links are not ok");
      }
    } catch (error) {
      setDisplayingDoneMessage(false);
      let substituteText = `Error: ${error.message}

Try something like:
[
  {
    "source": "x",
    "target": "y",
    "distance": 99999.99999999999,
    "reasoning": "blah blah"
  },
  {
    "source": "y",
    "target": "z",
    "distance": 1,
    "reasoning": "blah blah"
  },
  {
    "source": "x",
    "target": "z",
    "distance": 10,
    "reasoning": "blah blah"
  }
]

Your old input was: ${value}`;
      setValue(substituteText);
    }
  };
  return (
    <form
      onSubmit={handleSubmitInner}
      className={`inline ${show ? "" : "hidden"}`}
    >
      <h3 className="text-lg mt-8">Load comparisons</h3>
      <p>These will override your current comparisons.</p>
      <br />
      <textarea
        value={value}
        onChange={handleTextChange}
        rows="10"
        cols="50"
        className=""
      />
      <br />
      <button
        className="bg-transparent hover:bg-blue-500 text-blue-700 font-semibold hover:text-white py-2 px-4 border border-blue-500 hover:border-transparent rounded mt-5 p-10"
        onClick={handleSubmitInner}
      >
        Change comparisons
      </button>
      &nbsp;
      <button
        className={
          displayingDoneMessage
            ? "bg-transparent text-blue-700 font-semibold py-2 px-4 border border-blue-500 rounded mt-5 p-10"
            : "hidden"
        }
      >
        Done!
      </button>
    </form>
  );
}