const nanoid = require('nanoid')

const pluralize = require('pluralize')

module.exports = {

getRemovable,

createId,

deepQuery

}

// Returns document ids that have unsatisfied relations

// Example: a comment that references a post that doesn't exist

function getRemovable(db, opts) {

const _ = this

const removable = []

_.each(db, (coll, collName) => {

_.each(coll, doc => {

_.each(doc, (value, key) => {

if (new RegExp(`${opts.foreignKeySuffix}$`).test(key)) {

// Remove foreign key suffix and pluralize it

// Example postId -> posts

const refName = pluralize.plural(

key.replace(new RegExp(`${opts.foreignKeySuffix}$`), '')

)

// Test if table exists

if (db[refName]) {

// Test if references is defined in table

const ref = _.getById(db[refName], value)

if (_.isUndefined(ref)) {

removable.push({ name: collName, id: doc.id })

}

}

}

})

})

})

return removable

}

// Return incremented id or uuid

// Used to override lodash-id's createId with utils.createId

function createId(coll) {

const _ = this

const idProperty = _.__id()

if (_.isEmpty(coll)) {

return 1

} else {

let id = _(coll).maxBy(idProperty)[idProperty]

// Increment integer id or generate string id

return _.isFinite(id) ? ++id : nanoid(7)

}

}

function deepQuery(value, q) {

const _ = this

if (value && q) {

if (_.isArray(value)) {

for (let i = 0; i < value.length; i++) {

if (_.deepQuery(value[i], q)) {

return true

}

}

} else if (_.isObject(value) && !_.isArray(value)) {

for (let k in value) {

if (_.deepQuery(value[k], q)) {

return true

}

}

} else if (

value

.toString()

.toLowerCase()

.indexOf(q) !== -1

) {

return true

}

}

}