import decodeMsgpack from './decodeMsgpack.js'
import { execMany } from './helper.js'
import { sqlite } from './init.js'

/**
 * This generates rankings for each map...
 * @module libs/database/processRankings
 */
export function processRankings() {
    const maps = sqlite.prepare(`SELECT * FROM maps`)

    for (const map of maps.iterate())
        sqlite
            .prepare(`
                INSERT INTO rankings
                (
                    map, category, points, player, time, date, rank, server, finishes
                )
                SELECT   a.map, b.category, b.points, a.player, a.time, a.date, a.rank, a.server, a.finishes
                FROM     (
                        SELECT   rank() OVER w AS rank,
                                map,
                                date,
                                player,
                                min(time) AS time,
                                server,
                                COUNT(*) AS finishes
                        FROM     race as a
                        WHERE    map = ?
                        GROUP BY player window w AS (ORDER BY time) ) AS a
                JOIN maps as b ON a.map = b.map 
                ORDER BY rank
            `)
            .run(map.map)
}

/**
 * This generates teamrankings for each map...
 * @module libs/database/processTeamRankings
 */
export function processTeamRankings() {
    const maps = sqlite.prepare(`SELECT map FROM maps`)

    for (const map of maps.iterate())
        sqlite
            .prepare(`
                INSERT INTO teamrankings
                (
                    player, map, id, time, date, server, teamrank, category, points
                )
                SELECT DISTINCT(r.player),
                                r.map, r.id, r.time, r.date,
                                Substring(n.server, 1, 3),
                                dense_rank() OVER w AS rank,
                                a.category, a.points
                FROM            ((
                                    SELECT DISTINCT id
                                    FROM            teamrace
                                    WHERE           map = ?
                                    ORDER BY        time) AS l
                                )
                LEFT JOIN       teamrace AS r
                ON              l.id = r.id
                INNER JOIN      race AS n
                ON              r.map = n.map
                AND             r.player = n.player
                AND             r.time = n.time 
                JOIN maps as a
                ON              r.map = a.map window w AS (ORDER BY r.time)
            `)
            .run(map.map)
}

/**
 * This generates a cache for all the dates the top record has been improved for each map...
 * @module libs/database/processTimeGraph
 */
export function processTimeGraph() {
    const maps = sqlite.prepare(`SELECT map FROM maps`)
    const finishes = sqlite.prepare(`SELECT * FROM race WHERE map = ? ORDER BY date`)
    for (const map of maps.iterate()) {
        let currentFinish
        let currentBest = 0
        
        for (const record of finishes.iterate(map.map)) {
            currentFinish = record.time
            if (currentFinish <= currentBest || currentBest == 0) {
                currentBest = currentFinish

                sqlite.prepare(`
                    INSERT INTO "graphRecordCache"
                    (
                        map, player, time, date, server
                    ) VALUES (?, ?, ?, ?, ?)
                `).run(
                    map.map,
                    record.player,
                    record.time,
                    record.date,
                    record.server
                )
            }
        }
    }
}

/**
 * This generates a fancy map table containing more data such total finishes, median time.
 * @module libs/database/processMaps
 */
export function processMaps() {
    const maps = sqlite.prepare(`SELECT map FROM oldmaps`)
    const finishes = sqlite.prepare(`SELECT * FROM race WHERE map = ? ORDER BY date`)

    for (const map of maps.iterate()) {
        const info = sqlite.prepare(`SELECT * FROM oldmaps WHERE map = ?`).get(map.map)

        const avgTime = sqlite.prepare(`SELECT avg(time) AS avgTime FROM race WHERE map = ?`).get(map.map)?.avgTime ?? -1
        const medianTime = sqlite.prepare(`SELECT median(time) as medianTime FROM race WHERE map = ?`).get(map.map)?.medianTime ?? -1

        const teams = sqlite.prepare(`SELECT COUNT(distinct(id)) AS 'teams' FROM teamrace WHERE map = ?`).get(map.map)?.teams ?? -1
        const topTeamTime = sqlite.prepare(`SELECT time as topTeamTime FROM teamrankings WHERE map = ? ORDER BY Time ASC LIMIT 1`).get(map.map)?.topTeamTime ?? -1

        const topTime = sqlite.prepare(`SELECT time as topTime FROM rankings WHERE map = ? ORDER BY Time ASC LIMIT 1`).get(map.map)?.topTime ?? -1


        const total = sqlite.prepare(`SELECT COUNT(*) AS 'total' FROM race WHERE map = ?`).get(map.map)?.total ?? -1
        const unique = sqlite.prepare(`SELECT COUNT(distinct(player)) AS 'unique' FROM race WHERE map = ?`).get(map.map)?.unique ?? -1

        
        sqlite.prepare(`
            INSERT INTO "maps"
            (
                map, category, points, stars, mapper, release,
                avgTime, medianTime, topTime, topTeamTime,
                finishesUnique, finishesTotal, finishesTeam
            ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
        `).run(
            info.map, info.category, info.points, info.stars, info.mapper, info.release,
            avgTime, medianTime, topTime, topTeamTime,
            unique, total, teams,
        )
    }
}

/**
 * This inserts all types of points into a table...
 * @module db/processAllPoints
 */
export function processAllPoints() {
    const msgpack = decodeMsgpack()

    const types = {
        points: msgpack.pointsRanks,
        pointsThisWeek: msgpack.pointsThisWeek,
        pointsThisMonth: msgpack.pointsThisMonth,
        pointsTeam: msgpack.teamRankPoints,
        pointsRank: msgpack.rankPoints,
    }

    /* Generate tables */
    sqlite.exec(`
        CREATE TABLE IF NOT EXISTS "points"
        (
            "type" varchar(16) NOT NULL,
            "rank" INTEGER NOT NULL,
            "player" varchar(16) NOT NULL,
            "points" INTEGER NOT NULL
        )
    `)

    /* Insert data */
    for (const type in types) {
        let rank = 1

        for (const entry of types[type]) {
            sqlite
                .prepare(`
                    INSERT INTO "points"
                    (
                        type, rank, player, points
                    ) VALUES (?, ?, ?, ?)
                `)
                .run(
                    type,
                    rank,
                    entry[0],
                    entry[1]
                )

            ++rank
        }
    }

    /* Generate indexes */
    execMany([
        `CREATE INDEX IF NOT EXISTS "idx_points_type" ON "points" ("type")`,
        `CREATE INDEX IF NOT EXISTS "Idx_points_rank" on "points" ("rank")`,
        `CREATE INDEX IF NOT EXISTS "Idx_points_name" on "points" ("player")`
    ])
}

export default {
    processAllPoints,
    processRankings,
    processTeamRankings,
    processMaps,
    processTimeGraph
}