import {
    FastifyInstance,
    Plugin,
    DefaultQuery,
    DefaultParams,
    DefaultHeaders,
    DefaultBody,
    RouteShorthandOptions,
} from 'fastify'

import { Server, IncomingMessage, ServerResponse } from 'http'

import { MIN_ID_LENGTH, MAX_ID_LENGTH, MAX_NAME_LENGTH, MIN_PASSWORD_LENGTH, INSTALLATION_PARTITION_KEY } from '../../constants'
import { tokenResponseSchema, selfSchema, errorSchema } from '../../schemas'
import { createAccessToken, createRefreshToken } from '../../lib/authentication'
import { getUser } from '../../lib/collections'
import { hashPassword, comparePassword, JWT } from '../../lib/crypto'
import { containerFor, getItem, queryItems, normalize, createQuerySpec } from '../../lib/database'
import { badRequestError, badRequestFormError, unauthorizedError, serverError } from '../../lib/errors'
import { tokenFromHeader } from '../../lib/http'
import { attachMedia } from '../../lib/media'
import { createInstallationId } from '../../lib/utils'

import {
    User,
    UserToken,
    Group,
    GroupInvitation,
    GroupMembership,
    UserItemType,
    UserPrivacyType,
    GroupItemType,
    GroupMembershipType,
    GroupRegistrationType,
    App,
    Installation,
} from '../../types/collections'
import { PluginOptions } from '../../types'

function registerRoute(server: FastifyInstance<Server, IncomingMessage, ServerResponse>) {
    interface Body {
        id: string
        name: string
        email: string
        password: string
        requiresApproval: boolean
        privacy: string
        about?: string
        imageUrl?: string
        coverImageUrl?: string
        group?: string
        invitation?: string
    }

    const options: RouteShorthandOptions = {
        schema: {
            body: {
                type: 'object',
                required: ['id', 'email', 'password'],
                properties: {
                    id: {
                        type: 'string',
                        minLength: MIN_ID_LENGTH,
                        maxLength: MAX_ID_LENGTH,
                    },
                    name: {
                        type: 'string',
                        maxLength: MAX_NAME_LENGTH,
                    },
                    email: {
                        type: 'string',
                        format: 'email',
                    },
                    password: {
                        type: 'string',
                        minLength: MIN_PASSWORD_LENGTH,
                    },
                    requiresApproval: { type: 'boolean' },
                    privacy: {
                        type: 'string',
                        enum: ['public', 'group', 'subscribers', 'private'],
                    },
                    about: { type: 'string' },
                    imageUrl: { type: 'string' },
                    coverImageUrl: { type: 'string' },
                    group: { type: 'string' },
                    invitation: { type: 'string' },
                },
            },
            response: {
                201: tokenResponseSchema,
                400: errorSchema,
            },
        },
    }

    server.post<DefaultQuery, DefaultParams, DefaultHeaders, Body>('/api/register', options, async (request, reply) => {
        if (!server.database) return serverError(reply)

        const { name, email, password, requiresApproval, privacy, about, imageUrl, coverImageUrl, invitation: code } = request.body
        const id = normalize(request.body.id)

        const userContainer = containerFor(server.database.client, 'Users')
        const groupContainer = containerFor(server.database.client, 'Groups')

        const existingUser = await getItem<User>({ container: userContainer, id })
        if (existingUser) return badRequestFormError(reply, 'id', 'User id already taken')

        let userPending = false
        let invitation: GroupInvitation | undefined
        let group: Group | undefined

        if (request.body.group) {
            group = await getItem<Group>({ container: groupContainer, id: request.body.group })
            if (!group) return badRequestFormError(reply, 'group', 'Group not found')

            if (code) {
                const invitationQuery = createQuerySpec(`
                    SELECT * FROM Groups g WHERE
                        g.id = @code
                        g.pk = @group AND
                        g.t = @type AND
                        g.active = true AND
                        g.expiration < GETCURRENTTIMESTAMP()
                `, {
                    code,
                    group: group.id,
                    type: GroupItemType.Invitation,
                })

                const invitations = await queryItems<GroupInvitation>({
                    container: groupContainer,
                    query: invitationQuery,
                    logger: request.log,
                })

                if (invitations.length === 0) return badRequestFormError(reply, 'invitation', 'Invalid invitation code')
                invitation = invitations[0]
            }

            if (group.registration === GroupRegistrationType.Closed && !invitation) return badRequestFormError(reply, 'group', 'Group registration closed')
            if (group.registration === GroupRegistrationType.Approval) userPending = true
        }

        const appContainer = containerFor(server.database.client, 'Apps')

        const apps = await queryItems<App>({
            container: appContainer,
            query: 'SELECT * FROM Apps a WHERE a.active = true AND a.preinstall = true',
            logger: request.log,
        })

        const installations: string[] = []

        for (const app of apps) {
            const installation: Installation = {
                id: createInstallationId(),
                pk: INSTALLATION_PARTITION_KEY,
                userId: id,
                appId: app.id,
                settings: {},
                created: Date.now(),
            }

            await appContainer.items.create<Installation>(installation)
            installations.push(installation.id)
        }

        const user: User = {
            id,
            pk: id,
            t: UserItemType.User,
            groupId: group ? group.id : undefined,
            name,
            about,
            email,
            emailVerified: false,
            passwordHash: await hashPassword(password),
            imageUrl,
            coverImageUrl,
            installations,
            awards: 0,
            points: 0,
            balance: 0,
            posts: 0,
            subscriberCount: 0,
            subscribedCount: 0,
            pending: userPending,
            requiresApproval,
            privacy: privacy as UserPrivacyType,
            paid: false,
            active: true,
            created: Date.now(),
        }

        const refreshToken = createRefreshToken(id, request.headers['user-agent'], request.ip)

        await userContainer.items.create<User>(user)
        await userContainer.items.create<UserToken>(refreshToken)

        if (group) {
            await groupContainer.items.create<GroupMembership>({
                pk: group.id,
                t: GroupItemType.Membership,
                userId: user.id,
                pending: userPending,
                membership: GroupMembershipType.Member,
                invitation: code,
                created: Date.now(),
            })

            if (invitation) {
                const invitationItem = groupContainer.item(invitation.id, group.id)
                const uses = invitation.uses + 1

                await invitationItem.replace<GroupInvitation>({
                    ...invitation,
                    uses,
                    active: invitation.limit ? uses > invitation.limit : true,
                })
            }
        }

        const mediaContainer = containerFor(server.database.client, 'Media')
        
        if (imageUrl) await attachMedia(mediaContainer, imageUrl)
        if (coverImageUrl) await attachMedia(mediaContainer, coverImageUrl)

        return {
            id,
            access: await createAccessToken(id),
            refresh: refreshToken.id,
        }
    })
}

function authenticateRoute(server: FastifyInstance<Server, IncomingMessage, ServerResponse>) {
    interface Body {
        id: string
        password: string
    }

    const options: RouteShorthandOptions = {
        schema: {
            body: {
                type: 'object',
                required: ['id', 'password'],
                properties: {
                    id: { type: 'string' },
                    password: { type: 'string' },
                },
            },
            response: {
                200: tokenResponseSchema,
                400: errorSchema,
            },
        },
    }

    server.post<DefaultQuery, DefaultParams, DefaultHeaders, Body>('/api/authenticate', options, async (request, reply) => {
        if (!server.database) return serverError(reply)

        const container = containerFor(server.database.client, 'Users')
        const id = normalize(request.body.id)

        const user = await getItem<User>({ container, id })
        if (!user) return badRequestFormError(reply, 'id', 'User not found')

        const result = await comparePassword(request.body.password, user.passwordHash)
        if (!result) return badRequestFormError(reply, 'password', 'Incorrect password')

        const refreshToken = createRefreshToken(user.id, request.headers['user-agent'], request.ip)
        await container.items.create(refreshToken)

        return {
            id,
            access: await createAccessToken(user.id),
            refresh: refreshToken.id,
        }
    })
}

function refreshRoute(server: FastifyInstance<Server, IncomingMessage, ServerResponse>) {
    interface Headers {
        [key: string]: string
        authorization: string
    }

    interface Body {
        refresh: string
    }

    const options: RouteShorthandOptions = {
        schema: {
            headers: {
                type: 'object',
                properties: {
                    authorization: { type: 'string' },
                },
            },
            body: {
                type: 'object',
                required: ['refresh'],
                properties: {
                    refresh: { type: 'string' },
                },
            },
            response: {
                201: tokenResponseSchema,
                400: errorSchema,
            },
        },
    }

    server.post<DefaultQuery, DefaultParams, Headers, Body>('/api/refresh', options, async (request, reply) => {
        if (!server.database) return serverError(reply)

        const tokenString = tokenFromHeader(request.headers.authorization)
        if (!tokenString) return badRequestError(reply, 'Access token required')

        let userId: string | undefined

        try {
            const tokenData = await JWT.verify(tokenString, {
                ignoreExpiration: true,
            })

            if (!tokenData.sub) return badRequestError(reply, 'Invalid token')
            if (!tokenData.exp) return badRequestError(reply, 'Invalid token')
    
            if ((tokenData.exp * 1000) > Date.now()) return badRequestError(reply, 'Token must be expired')
            userId = tokenData.sub
        } catch (err) {
            request.log.error(err)
            return badRequestError(reply, 'Invalid token')
        }

        const container = containerFor(server.database.client, 'Users')
        const tokenItem = container.item(request.body.refresh, userId)

        if (!tokenItem) return badRequestError(reply, 'Invalid refresh token')
        const { resource: token } = await tokenItem.read<UserToken>()

        if (token.expires < Date.now()) return badRequestError(reply, 'Refresh token expired')

        await tokenItem.delete()

        const newRefreshToken = createRefreshToken(userId, request.headers['user-agent'], request.ip)
        await container.items.create(newRefreshToken)

        reply.code(201)

        return {
            id: userId,
            access: await createAccessToken(userId),
            refresh: newRefreshToken.id,
            expires: newRefreshToken.expires,
        }
    })
}

function selfRoute(server: FastifyInstance<Server, IncomingMessage, ServerResponse>) {
    const options: RouteShorthandOptions = {
        schema: {
            response: {
                200: selfSchema,
                400: errorSchema,
            },
        },
    }

    server.get<DefaultQuery, DefaultParams, DefaultHeaders, DefaultBody>('/api/self', options, async (request, reply) => {
        if (!server.database) return serverError(reply)
        if (!request.viewer) return unauthorizedError(reply)

        const viewer = await getUser(server.database.client, request.viewer.id)
        if (!viewer) return unauthorizedError(reply)

        return viewer
    })
}

const plugin: Plugin<Server, IncomingMessage, ServerResponse, PluginOptions> = async server => {
    registerRoute(server)
    authenticateRoute(server)
    refreshRoute(server)
    selfRoute(server)
}

export default plugin