/* ----------------------------------------------------------------------------

 Question Server
 GitLab: <https://gitlab.com/MrFry/mrfrys-node-server>

 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program. If not, see <https://www.gnu.org/licenses/>.

 ------------------------------------------------------------------------- */

import { v4 as uuidv4, v5, validate as validateuuid } from 'uuid'
import type { Database } from 'better-sqlite3'

import logger from '../../../utils/logger'
import utils from '../../../utils/utils'
import {
    Request,
    SubmoduleData,
    User,
    Submodule,
} from '../../../types/basicTypes'
import dbtools from '../../../utils/dbtools'

const minimumAlowwedSessions = 2 // how many sessions are allowed for a user
const usersDbBackupPath = 'data/dbs/backup'

const maxPWCount = 3
const daysAfterUserGetsPWs = 7 // days after user gets pw-s

interface Session {
    id: string
    userId: number
    createDate: string
    lastAccess: string
    isScript: number
}

function BackupDB(usersDbBackupPath: string, userDB: Database) {
    logger.Log('Backing up auth DB ...')
    utils.CreatePath(usersDbBackupPath, true)
    userDB
        .backup(
            `${usersDbBackupPath}/users.${utils
                .GetDateString()
                .replace(/ /g, '_')}.db`
        )
        .then(() => {
            logger.Log('Auth DB backup complete!')
        })
        .catch((err: Error) => {
            logger.Log('Auth DB backup failed!', logger.GetColor('redbg'))
            console.error(err)
        })
}

function createDefaultUser(userDb: Database) {
    logger.Log('The user DB is empty, creating user #1', 'yellowbg')
    const pw = uuidv4()
    const insertRes = dbtools.Insert(userDb, 'users', {
        pw: pw,
        avaiblePWRequests: 0,
        created: utils.GetDateString(),
    })
    logger.Log('ID and PW for user #1: ', 'yellowbg')
    console.log(`ID: #${insertRes.lastInsertRowid}, PW: "${pw}"`)
    logger.Log('It can be also viewed in the users db file.')
}

// TODO: figure out if this is needed
// const validationTokenNameFile = 'data/validationTokenName'
// function readValidationTokenName() {
//     if (utils.FileExists(validationTokenNameFile)) {
//         return utils.ReadFile(validationTokenNameFile)
//     } else {
//         throw new Error(
//             `Validation token file does not exist! Should be: "${validationTokenNameFile}", content should be: "name for uuidv5 (any text)"`
//         )
//     }
// }
const validationTokenName = 'qmining' // readValidationTokenName()

function setup(data: SubmoduleData): Submodule {
    const { app, userDB, url /* publicdirs, moduleSpecificData */ } = data
    const domain: any = url
    logger.DebugLog(`Cookie domain: ${domain}`, 'cookie', 1)

    const userCount = dbtools
        .TableInfo(userDB, 'users')
        .dataCount.toLocaleString()
    logger.Log(`User count: ${userCount} users`, 'blue')
    if (+userCount === 0) {
        createDefaultUser(userDB)
    }

    app.get('/avaiblePWS', (req: Request, res: any) => {
        logger.LogReq(req)

        const user: User = req.session.user

        res.json({
            success: true,
            userCreated: user.created,
            availablePWS: user.avaiblePWRequests,
            requestedPWS: user.pwRequestCount,
            maxPWCount: maxPWCount,
            daysAfterUserGetsPWs: daysAfterUserGetsPWs,
            dayDiff: getDayDiff(user.created),
            userCount: dbtools.TableInfo(userDB, 'users').dataCount,
        })
    })

    app.post('/getpw', function (req: Request, res: any) {
        logger.LogReq(req)

        const requestingUser = req.session.user

        if (requestingUser.avaiblePWRequests <= 0) {
            res.json({
                result: 'error',
                success: false,
                msg: 'Too many passwords requested or cant request password yet, try later',
            })
            logger.Log(
                `User #${requestingUser.id} requested too much passwords`,
                logger.GetColor('cyan')
            )
            return
        }

        dbtools.Update(
            userDB,
            'users',
            {
                avaiblePWRequests: requestingUser.avaiblePWRequests - 1,
                pwRequestCount: requestingUser.pwRequestCount + 1,
            },
            {
                id: requestingUser.id,
            }
        )

        const pw = uuidv4()
        const insertRes = dbtools.Insert(userDB, 'users', {
            pw: pw,
            avaiblePWRequests: 0,
            created: utils.GetDateString(),
            createdBy: requestingUser.id,
        })

        logger.Log(
            `User #${requestingUser.id} created new user #${insertRes.lastInsertRowid}`,
            logger.GetColor('cyan')
        )

        res.json({
            pw: pw,
            success: true,
            userCreated: requestingUser.created,
            availablePWS: requestingUser.avaiblePWRequests,
            requestedPWS: requestingUser.pwRequestCount,
            maxPWCount: maxPWCount,
            daysAfterUserGetsPWs: daysAfterUserGetsPWs,
            dayDiff: getDayDiff(requestingUser.created),
            userCount: dbtools.TableInfo(userDB, 'users').dataCount,
        })
    })

    app.post('/login', (req: Request, res: any) => {
        logger.LogReq(req)
        const pw = req.body.pw
            ? req.body.pw.replace(/'/g, '').replace(/"/g, '').replace(/;/g, '')
            : false
        const isScript = req.body.script
        const user: User = dbtools.Select(userDB, 'users', {
            pw: pw,
        })[0]

        if (user) {
            const sessionID = uuidv4()

            const existingSessions = dbtools
                .Select(userDB, 'sessions', {
                    userID: user.id,
                    isScript: isScript ? 1 : 0,
                })
                .sort((a: Session, b: Session) => {
                    return (
                        new Date(a.lastAccess).getTime() -
                        new Date(b.lastAccess).getTime()
                    )
                })

            const diff = existingSessions.length - minimumAlowwedSessions
            if (diff > 0) {
                logger.Log(
                    `Multiple ${isScript ? 'script' : 'website'} sessions ( ${
                        existingSessions.length
                    } ) for #${user.id}, deleting olds`,
                    logger.GetColor('cyan')
                )
                for (let i = 0; i < diff; i++) {
                    const id = existingSessions[i].id
                    dbtools.Delete(userDB, 'sessions', {
                        id: id,
                        isScript: isScript ? 1 : 0,
                    })
                }
            }

            dbtools.Update(
                userDB,
                'users',
                {
                    loginCount: user.loginCount + 1,
                    lastLogin: utils.GetDateString(),
                },
                {
                    id: user.id,
                }
            )

            dbtools.Insert(userDB, 'sessions', {
                id: sessionID,
                userID: user.id,
                isScript: isScript ? 1 : 0,
                createDate: utils.GetDateString(),
            })

            // https://www.npmjs.com/package/cookie
            res.cookie('sessionID', sessionID, {
                domain: domain,
                expires: new Date(
                    new Date().getTime() + 10 * 365 * 24 * 60 * 60 * 1000
                ),
                sameSite: 'none',
                secure: true,
            })
            res.cookie('sessionID', sessionID, {
                expires: new Date(
                    new Date().getTime() + 10 * 365 * 24 * 60 * 60 * 1000
                ),
                sameSite: 'none',
                secure: true,
            })

            res.json({
                result: 'success',
                msg: 'you are now logged in',
            })
            logger.Log(
                `Successfull login to ${
                    isScript ? 'script' : 'website'
                } with user ID: #${user.id}`,
                logger.GetColor('cyan')
            )
        } else {
            logger.Log(
                `Login attempt with invalid pw: ${pw} to ${
                    isScript ? 'script' : 'website'
                }`,
                logger.GetColor('cyan')
            )
            res.json({
                result: 'error',
                msg: 'Invalid password',
            })
        }
    })

    app.get('/logout', (req: Request, res: any) => {
        logger.LogReq(req)
        const sessionID = req.cookies.sessionID
        const user: User = req.session.user
        const { all } = req.query

        if (!user) {
            res.json({
                msg: 'You are not logged in',
                success: false,
            })
            return
        }

        logger.Log(
            `Successfull logout with user ID: #${user.id}`,
            logger.GetColor('cyan')
        )

        if (all) {
            dbtools.Delete(userDB, 'sessions', {
                userID: user.id,
            })
        } else {
            dbtools.Delete(userDB, 'sessions', {
                id: sessionID,
            })
        }

        res.clearCookie('sessionID').json({
            msg: 'Successfull logout',
            result: 'success',
        })
    })

    app.get(
        '/validationtoken',
        (req: Request<{ token: string; userid: string }>, res: any) => {
            logger.LogReq(req)
            const user: User = req.session.user
            const { token, userid } = req.query

            if (validateuuid(token) && !Number.isNaN(+userid)) {
                const specifiedUser = dbtools.Select(userDB, 'users', {
                    id: +userid,
                })

                if (specifiedUser.length === 0) {
                    res.json({
                        result: 'error',
                        msg: 'couldnt find user',
                    })
                }
                const key = v5(validationTokenName, specifiedUser[0].pw)
                const isValid = key === token

                res.json({
                    result: 'success',
                    isValid: isValid,
                })
            } else {
                const key = v5(validationTokenName, user.pw)

                res.json({
                    result: 'success',
                    key: key,
                    ...((token || userid) && {
                        msg: 'userid or token was provided, but was invalid',
                    }),
                })
            }
        }
    )

    function getDayDiff(dateString: string | Date | number) {
        const msdiff = new Date().getTime() - new Date(dateString).getTime()
        return Math.floor(msdiff / (1000 * 3600 * 24))
    }

    function IncrementAvaiblePWs() {
        // FIXME: check this if this is legit and works
        logger.Log('Incrementing avaible PW-s ...')
        const users: Array<User> = dbtools.SelectAll(userDB, 'users')
        const day = new Date().getDay()

        if (day === 1) {
            users.forEach((user) => {
                const dayDiff = getDayDiff(user.created)
                if (dayDiff < daysAfterUserGetsPWs) {
                    logger.Log(
                        `User #${user.id} is not registered long enough to get password ( ${dayDiff} days, ${daysAfterUserGetsPWs} needed)`,
                        logger.GetColor('cyan')
                    )
                    return
                }

                if (user.avaiblePWRequests >= maxPWCount) {
                    return
                }

                logger.Log(
                    `Setting avaible PW-s for user #${user.id}: ${user.avaiblePWRequests} -> ${maxPWCount}`,
                    logger.GetColor('cyan')
                )

                dbtools.Update(
                    userDB,
                    'users',
                    {
                        avaiblePWRequests: maxPWCount,
                    },
                    {
                        id: user.id,
                    }
                )
            })
        }

        users.forEach((user) => {
            const dayDiff = getDayDiff(user.created)
            if (dayDiff === daysAfterUserGetsPWs) {
                logger.Log(
                    `Setting avaible PW-s for user #${user.id}: ${user.avaiblePWRequests} -> ${maxPWCount}`,
                    logger.GetColor('cyan')
                )

                dbtools.Update(
                    userDB,
                    'users',
                    {
                        avaiblePWRequests: maxPWCount,
                    },
                    {
                        id: user.id,
                    }
                )
            }
        })
    }

    return {
        dailyAction: () => {
            BackupDB(usersDbBackupPath, userDB)
            IncrementAvaiblePWs()
        },
    }
}

export default {
    setup: setup,
}