'use strict'
const crs = require('crypto-random-string')
const appRoot = require('app-root-path')
const knex = require(`${appRoot}/db/knex`)

const Streams = () => knex('streams')
const Acl = () => knex('stream_acl')

const debug = require('debug')
const { createBranch } = require('./branches')

module.exports = {
  async createStream({ name, description, isPublic, ownerId }) {
    let stream = {
      id: crs({ length: 10 }),
      name: name || generateStreamName(),
      description: description || '',
      isPublic: isPublic !== false,
      updatedAt: knex.fn.now()
    }

    // Create the stream & set up permissions
    let [{ id: streamId }] = await Streams().returning('id').insert(stream)
    await Acl().insert({ userId: ownerId, resourceId: streamId, role: 'stream:owner' })

    // Create a default main branch
    await createBranch({
      name: 'main',
      description: 'default branch',
      streamId: streamId,
      authorId: ownerId
    })
    return streamId
  },

  async getStream({ streamId, userId }) {
    let stream = await Streams().where({ id: streamId }).select('*').first()
    if (!userId) return stream

    let acl = await Acl().where({ resourceId: streamId, userId: userId }).select('role').first()
    if (acl) stream.role = acl.role
    return stream
  },

  async updateStream({ streamId, name, description, isPublic }) {
    let [{ id }] = await Streams()
      .returning('id')
      .where({ id: streamId })
      .update({ name, description, isPublic, updatedAt: knex.fn.now() })
    return id
  },

  async grantPermissionsStream({ streamId, userId, role }) {
    // upserts the existing role (sets a new one!)
    // TODO: check if we're removing the last owner (ie, does the stream still have an owner after this operation)?
    let query =
      Acl().insert({ userId: userId, resourceId: streamId, role: role }).toString() +
      ' on conflict on constraint stream_acl_pkey do update set role=excluded.role'

    await knex.raw(query)

    // update stream updated at
    await Streams().where({ id: streamId }).update({ updatedAt: knex.fn.now() })
    return true
  },

  async revokePermissionsStream({ streamId, userId }) {
    let streamAclEntriesCount = Acl().count({ resourceId: streamId })
    // TODO: check if streamAclEntriesCount === 1 then throw big boo-boo (can't delete last ownership link)

    if (streamAclEntriesCount === 1)
      throw new Error('Stream has only one ownership link left - cannot revoke permissions.')

    // TODO: below behaviour not correct. Flow:
    // Count owners
    // If owner count > 1, then proceed to delete, otherwise throw an error (can't delete last owner - delete stream)

    let aclEntry = await Acl().where({ resourceId: streamId, userId: userId }).select('*').first()

    if (aclEntry.role === 'stream:owner') {
      let ownersCount = Acl().count({ resourceId: streamId, role: 'stream:owner' })
      if (ownersCount === 1) throw new Error('Could not revoke permissions for user')
      else {
        await Acl().where({ resourceId: streamId, userId: userId }).del()
        return true
      }
    }

    let delCount = await Acl().where({ resourceId: streamId, userId: userId }).del()

    if (delCount === 0) throw new Error('Could not revoke permissions for user')

    // update stream updated at
    await Streams().where({ id: streamId }).update({ updatedAt: knex.fn.now() })

    return true
  },

  async deleteStream({ streamId }) {
    debug('speckle:db')('Deleting stream ' + streamId)

    // Delete stream commits (not automatically cascaded)
    await knex.raw(
      `
      DELETE FROM commits WHERE id IN (
        SELECT sc."commitId" FROM streams s
        INNER JOIN stream_commits sc ON s.id = sc."streamId"
        WHERE s.id = ?
      )
      `,
      [streamId]
    )
    return await Streams().where({ id: streamId }).del()
  },

  async getUserStreams({ userId, limit, cursor, publicOnly, searchQuery }) {
    limit = limit || 25
    publicOnly = publicOnly !== false //defaults to true if not provided

    let query = Acl()
      .columns([
        { id: 'streams.id' },
        'name',
        'description',
        'isPublic',
        'createdAt',
        'updatedAt',
        'role'
      ])
      .select()
      .join('streams', 'stream_acl.resourceId', 'streams.id')
      .where('stream_acl.userId', userId)

    if (cursor) query.andWhere('streams.updatedAt', '<', cursor)

    if (publicOnly) query.andWhere('streams.isPublic', true)

    if (searchQuery)
      query.andWhere(function () {
        this.where('name', 'ILIKE', `%${searchQuery}%`)
          .orWhere('description', 'ILIKE', `%${searchQuery}%`)
          .orWhere('id', 'ILIKE', `%${searchQuery}%`) //potentially useless?
      })

    query.orderBy('streams.updatedAt', 'desc').limit(limit)

    let rows = await query
    return {
      streams: rows,
      cursor: rows.length > 0 ? rows[rows.length - 1].updatedAt.toISOString() : null
    }
  },

  async getStreams({ offset, limit, orderBy, visibility, searchQuery }) {
    let query = knex
      .column('streams.*', knex.raw('coalesce(sum(pg_column_size(objects.data)),0) as size'))
      .select()
      .from('streams')
      .leftJoin('objects', 'streams.id', 'objects.streamId')
      .groupBy('streams.id')

    let countQuery = Streams()

    if (searchQuery) {
      const whereFunc = function () {
        this.where('streams.name', 'ILIKE', `%${searchQuery}%`).orWhere(
          'streams.description',
          'ILIKE',
          `%${searchQuery}%`
        )
      }
      query.where(whereFunc)
      countQuery.where(whereFunc)
    }
    if (visibility && visibility !== 'all') {
      if (!['private', 'public'].includes(visibility))
        throw new Error('Stream visibility should be either private, public or all')
      let isPublic = visibility === 'public'
      const publicFunc = function () {
        this.where({ isPublic })
      }
      query.andWhere(publicFunc)
      countQuery.andWhere(publicFunc)
    }
    let [res] = await countQuery.count()
    let count = parseInt(res.count)

    if (!count) return { streams: [], totalCount: 0 }

    orderBy = orderBy || 'updatedAt,desc'

    let [columnName, order] = orderBy.split(',')

    let rows = await query.orderBy(`${columnName}`, order).offset(offset).limit(limit)

    return { streams: rows, totalCount: count }
  },

  async getUserStreamsCount({ userId, publicOnly, searchQuery }) {
    publicOnly = publicOnly !== false //defaults to true if not provided

    let query = Acl()
      .count()
      .join('streams', 'stream_acl.resourceId', 'streams.id')
      .where({ userId: userId })

    if (publicOnly) query.andWhere('streams.isPublic', true)

    if (searchQuery)
      query.andWhere(function () {
        this.where('name', 'ILIKE', `%${searchQuery}%`)
          .orWhere('description', 'ILIKE', `%${searchQuery}%`)
          .orWhere('id', 'ILIKE', `%${searchQuery}%`) //potentially useless?
      })

    let [res] = await query
    return parseInt(res.count)
  },

  async getStreamUsers({ streamId }) {
    let query = Acl()
      .columns({ role: 'stream_acl.role' }, 'id', 'name', 'company', 'avatar')
      .select()
      .where({ resourceId: streamId })
      .rightJoin('users', { 'users.id': 'stream_acl.userId' })
      .select('stream_acl.role', 'name', 'id', 'company', 'avatar')
      .orderBy('stream_acl.role')

    return await query
  }
}

const adjectives = [
  'Tall',
  'Curved',
  'Stacked',
  'Purple',
  'Pink',
  'Rectangular',
  'Circular',
  'Oval',
  'Shiny',
  'Speckled',
  'Blue',
  'Stretched',
  'Round',
  'Spherical',
  'Majestic',
  'Symmetrical'
]

const nouns = [
  'Building',
  'House',
  'Treehouse',
  'Tower',
  'Tunnel',
  'Bridge',
  'Pyramid',
  'Structure',
  'Edifice',
  'Palace',
  'Castle',
  'Villa'
]

const generateStreamName = () => {
  return `${adjectives[Math.floor(Math.random() * adjectives.length)]} ${
    nouns[Math.floor(Math.random() * nouns.length)]
  }`
}