/* eslint-disable no-underscore-dangle */
/* eslint-disable no-param-reassign */
/* eslint-disable no-use-before-define */

export default function buildQueryPlugin(schema) {
  function apiQuery(rawParams, locale, cb) {
    const model = this;
    const params = paramParser(this, rawParams, locale);

    if (cb) {
      model
        .find(params.searchParams)
        .exec(cb);
    }

    return params.searchParams;
  }

  schema.statics.apiQuery = apiQuery;
}

export function paramParser(model, rawParams, locale) {
  let query = {
    searchParams: {},
    sort: false,
  };

  // Construct searchParams
  Object.keys(rawParams).forEach((key) => {
    const separatedParams = rawParams[key]
      .match(/{\w+}(.[^{}]*)/g);

    if (separatedParams === null) {
      query = parseParam(key, rawParams[key], model, query, locale);
    } else {
      separatedParams.forEach((param) => {
        query = parseParam(key, param, model, query, locale);
      });
    }
  });

  return query;
}

function convertToBoolean(str) {
  return str.toLowerCase() === 'true'
    || str.toLowerCase() === 't'
    || str.toLowerCase() === 'yes'
    || str.toLowerCase() === 'y'
    || str === '1';
}

function addSearchParam(query, key, value) {
  if (typeof query.searchParams[key] !== 'undefined') {
    value.forEach((i) => {
      query.searchParams[key][i] = value[i];
    });
  } else {
    query.searchParams[key] = value;
  }
  return query;
}

function parseParam(key, val, model, query, locale) {
  const lcKey = key;
  let operator = val.match(/\{(.*)\}/);
  val = val.replace(/\{(.*)\}/, '');

  if (operator) [, operator] = operator;

  if (val === '') {
    return {};
  } if (lcKey === 'sort_by' || lcKey === 'order_by') {
    const parts = val.split(',');
    query.sort = {};
    query.sort[parts[0]] = parts[1] === 'asc' || parts.length <= 1 ? 1 : parts[1];
  } else if (lcKey === 'include') {
    if (val.match(',')) {
      const orArray = [];
      val.split(',').map(id => orArray.push({ _id: id }));
      query = addSearchParam(query, '$or', orArray);
    } else query.searchParams._id = val;
  } else if (lcKey === 'exclude') {
    if (val.match(',')) {
      const andArray = [];
      val.split(',').map(id => andArray.push({ _id: { $ne: id } }));
      query = addSearchParam(query, '$and', andArray);
    } else query.searchParams._id = { $ne: val };
  } else if (lcKey === 'locale') {
    // Do nothing
  } else if (lcKey === 'depth') {
    query.maxDepth = val;
  } else {
    query = parseSchemaForKey(model.schema, query, '', lcKey, val, operator, locale);
  }
  return query;
}

function parseSchemaForKey(schema, query, keyPrefix, lcKey, val, operator, locale) {
  let paramType;
  let key = keyPrefix + lcKey;
  const matches = lcKey.match(/(.+)\.(.+)/);

  if (matches) {
    // Parse SubSchema
    if (schema.paths[matches[1]].constructor.name === 'DocumentArray'
      || schema.paths[matches[1]].constructor.name === 'Mixed') {
      parseSchemaForKey(schema.paths[matches[1]].schema, `${matches[1]}.`, matches[2], val, operator);
    } else if (schema.paths[matches[1]].constructor.name === 'SchemaType'
      || schema.paths[matches[1]].constructor.name === 'SingleNestedPath') {
      // This wasn't handled in the original package but seems to work
      paramType = schema.paths[matches[1]].schema.paths.name.instance;
    }
  } else if (schema.obj[lcKey] && typeof schema === 'object') {
    if (schema.obj[lcKey].localized) {
      key = `${key}.${locale}`;
    }
    paramType = schema.obj[lcKey].name || schema.obj[lcKey].type.name;
  } else if (typeof schema === 'undefined') {
    paramType = 'String';
  } else if (typeof schema.paths[lcKey] === 'undefined') {
    // nada, not found
  } else if (schema.paths[lcKey].constructor.name === 'SchemaBoolean') {
    paramType = 'Boolean';
  } else if (schema.paths[lcKey].constructor.name === 'SchemaString') {
    paramType = 'String';
  } else if (schema.paths[lcKey].constructor.name === 'SchemaNumber') {
    paramType = 'Number';
  } else if (schema.paths[lcKey].constructor.name === 'ObjectId') {
    paramType = 'ObjectId';
  } else if (schema.paths[lcKey].constructor.name === 'SchemaArray') {
    paramType = 'Array';
  }

  if (paramType === 'Boolean') {
    query = addSearchParam(query, key, convertToBoolean(val));
  } else if (paramType === 'Number') {
    if (val.match(/([0-9]+,?)/) && val.match(',')) {
      if (operator === 'all') {
        query = addSearchParam(query, key, { $all: val.split(',') });
      } else if (operator === 'nin') {
        query = addSearchParam(query, key, { $nin: val.split(',') });
      } else if (operator === 'mod') {
        query = addSearchParam(query, key, { $mod: [val.split(',')[0], val.split(',')[1]] });
      } else {
        query = addSearchParam(query, key, { $in: val.split(',') });
      }
    } else if (val.match(/([0-9]+)/)) {
      if (operator === 'gt'
        || operator === 'gte'
        || operator === 'lt'
        || operator === 'lte'
        || operator === 'ne') {
        const newParam = {};
        newParam[`$${operator}`] = val;
        query = addSearchParam(query, key, newParam);
      } else {
        query = addSearchParam(query, key, parseInt(val, 0));
      }
    }
  } else if (paramType === 'String') {
    if (val.match(',')) {
      const options = val.split(',').map(str => new RegExp(str, 'i'));

      if (operator === 'all') {
        query = addSearchParam(query, key, { $all: options });
      } else if (operator === 'nin') {
        query = addSearchParam(query, key, { $nin: options });
      } else {
        query = addSearchParam(query, key, { $in: options });
      }
    } else if (val.match(/([0-9]+)/)) {
      if (operator === 'gt'
        || operator === 'gte'
        || operator === 'lt'
        || operator === 'lte') {
        const newParam = {};
        newParam[`$${operator}`] = val;
        query = addSearchParam(query, key, newParam);
      } else {
        query = addSearchParam(query, key, val);
      }
    } else if (operator === 'ne' || operator === 'not') {
      const neregex = new RegExp(val, 'i');
      query = addSearchParam(query, key, { $not: neregex });
    } else if (operator === 'like') {
      query = addSearchParam(query, key, { $regex: val, $options: '-i' });
    } else {
      query = addSearchParam(query, key, val);
    }
  } else if (paramType === 'ObjectId') {
    query = addSearchParam(query, key, val);
  } else if (paramType === 'Array') {
    query = addSearchParam(query, key, val);
  }
  return query;
}