// utils
const { nanoid } = require('nanoid');

// import json with initial data
let events = require('../data/eventsData.json');
const eventDefs = require('../data/eventsDefinition.js');

// aux
const replaceAt = (array, index, value) => {
  const ret = array.slice(0);
  ret[index] = value;
  return ret;
};

// Create controller for GET request to '/events/all'
// Returns -
exports.eventsGetAll = async (req, res) => {
  res.json(events);
};

// Create controller for GET request to '/events/:Id'
// Returns -
exports.eventsGetById = async (req, res) => {
  // TODO
};

// Create controller for POST request to '/events/'
// Returns -
exports.eventsPost = async (req, res) => {
  // TODO: Validate event
  if (!req.body) {
    res.sendStatus(400);
    return;
  }

  // ensure structure
  let newEvent = {};
  req.body.id = nanoid(6);

  switch (req.body.type) {
    case 'event':
      newEvent = { ...eventDefs.event, ...req.body };
      break;
    case 'delay':
      newEvent = { ...eventDefs.delay, ...req.body };
      break;
    case 'block':
      newEvent = { ...eventDefs.block, ...req.body };
      break;

    default:
      res.sendStatus(400);
      break;
  }

  // Torbjorn: hmmmmmmm, can we look here?
  if (newEvent.order <= 0) {
    newEvent.order = 0;
    // insert at top
    events.forEach((e) => {
      e.order = e.order + 1;
    });
    events = [newEvent, ...events];
  } else if (newEvent.order >= events.length) {
    newEvent.order = events.length;
    events = [...events, newEvent];
  } else {
    let before = events.slice(0, newEvent.order);
    let after = events.slice(newEvent.order);
    // move all items one element down, starting from new position
    after.forEach((e) => {
      e.order = e.order + 1;
    });
    events = [...before, newEvent, ...after];
  }
  console.log('added', events);
  res.sendStatus(201);
};

// Create controller for PUT request to '/events/:id'
// Returns -
exports.eventsPut = async (req, res) => {
  const itemIndex = events.findIndex((e) => e.id == req.body.id);

  // Item with index not found
  if (itemIndex === -1) {
    res.sendStatus(400);
    return;
  }

  // Torbjorn: bad syntax?
  const newEvents = replaceAt(events, itemIndex, req.body);
  events = [...newEvents];
  res.sendStatus(200);
};

// Create controller for PATCH request to '/events/:id'
// Returns -
exports.eventsPatch = async (req, res) => {
  const itemIndex = events.findIndex((e) => e.id == req.body.id);

  // Item with index not found
  if (itemIndex === -1) {
    res.sendStatus(400);
    return;
  }

  // Get current object
  const eventToUpdate = events[itemIndex];

  // Update and replace
  const updatedEvent = { ...eventToUpdate, ...req.body };
  const newEvents = replaceAt(events, itemIndex, updatedEvent);

  events = [...newEvents];
  res.send(updatedEvent);
};

// Create controller for DELETE request to '/events/'
// Returns -
exports.eventsDelete = async (req, res) => {
  if (!req.params.id) {
    res.sendStatus(400);
  }

  const itemIndex = events.findIndex((e) => e.id == req.params.id);

  if (itemIndex === -1) {
    res.sendStatus(400);
    return;
  } else if (itemIndex === 0) events.shift();
  else events.splice(itemIndex, 1);

  // Update events
  events = [...events];
  res.sendStatus(200);
};