_ = require 'lodash'
expressSession = require 'express-session'
permissions = require '../sbvr-api/permissions'

sessionAPI = null

sessionModel = '''
	Vocabulary: session

	Term:       session id
		Concept Type: Short Text (Type)
	Term:       data
		Concept Type: JSON (Type)
	Term:       expiry time
		Concept type: Date Time (Type)

	Term:       session
		Database ID Field: session id
		Reference Scheme: session id

	Fact type:  session has data
		Necessity: Each session has exactly 1 data
	Fact type:  session has session id
		Necessity: Each session has exactly 1 session id
		Necessity: Each session id is of exactly 1 session
	Fact type:  session has expiry time
		Necessity: Each session has at most 1 expiry time'''

class PinejsSessionStore extends expressSession.Store
	constructor: ->
	get: (sid, callback) ->
		sessionAPI.get
			resource: 'session'
			id: sid
			passthrough: req: permissions.rootRead
			options:
				$select: 'data'
		.then (session) ->
			return session?.data
		.nodeify(callback)

	set: (sid, data, callback) ->
		body =
			session_id: sid
			data: data
			expiry_time: data?.cookie?.expires ? null
		sessionAPI.put
			resource: 'session'
			id: sid
			passthrough: req: permissions.root
			body: body
		.nodeify(callback)

	destroy: (sid, callback) ->
		sessionAPI.delete
			resource: 'session'
			id: sid
			passthrough: req: permissions.root
		.nodeify(callback)

	all: (callback) ->
		sessionAPI.get
			resource: 'session'
			passthrough: req: permissions.root
			options:
				$select: 'session_id'
				$filter: expiry_time: $ge: Date.now()
		.then (sessions) ->
			_.map(sessions, 'session_id')
		.nodeify(callback)

	clear: (callback) ->
		# TODO: Use a truncate
		sessionAPI.delete
			resource: 'session'
			passthrough: req: permissions.root
		.nodeify(callback)

	length: (callback) ->
		sessionAPI.get
			resource: 'session/$count'
			passthrough: req: permissions.rootRead
			options:
				$select: 'session_id'
				$filter: expiry_time: $ge: Date.now()
		.nodeify(callback)
PinejsSessionStore.config =
	models: [
		modelName: 'session',
		modelText: sessionModel
		apiRoot: 'session'
		logging:
			default: false
			error: true
		customServerCode: PinejsSessionStore
	]
PinejsSessionStore.setup = (app, sbvrUtils, db, callback) ->
	sessionAPI = sbvrUtils.api.session
	callback()

module.exports = PinejsSessionStore