package dao

import (
	"context"
	"database/sql"

	"git.xeserv.us/xena/gorqlite"
	"github.com/opentracing/opentracing-go"
	splog "github.com/opentracing/opentracing-go/log"
)

type Users struct {
	conn gorqlite.Connection
}

func NewUsers(conn gorqlite.Connection) *Users {
	return &Users{conn: conn}
}

func (u *Users) Migrate(ctx context.Context) error {
	sp, ctx := opentracing.StartSpanFromContext(ctx, "users.migrate")
	defer sp.Finish()

	migrationDDL := []string{
		`CREATE TABLE IF NOT EXISTS users(id INTEGER PRIMARY KEY, discord_id TEXT UNIQUE, score INTEGER)`,
	}

	res, err := u.conn.Write(migrationDDL)
	if err != nil {
		sp.LogFields(splog.Error(err))
	}

	for i, re := range res {
		if re.Err != nil {
			sp.LogFields(splog.Error(err))
			return err
		}

		sp.LogFields(splog.Int("migration.step", i), splog.Float64("timing", re.Timing), splog.Int64("rows.affected", re.RowsAffected))
	}

	return nil
}

func (u *Users) Insert(ctx context.Context, discordID string) (int64, error) {
	sp, ctx := opentracing.StartSpanFromContext(ctx, "users.insert")
	defer sp.Finish()
	sp.LogFields(splog.String("discord.id", discordID))

	re, err := u.conn.WriteOne(gorqlite.NewPreparedStatement("INSERT INTO users (discord_id, score) VALUES (%s, 0)").Bind(discordID))
	if err != nil {
		sp.LogFields(splog.Error(err))
		sp.LogFields(splog.Error(re.Err))
		return -1, err
	}

	if re.Err != nil {
		sp.LogFields(splog.Error(re.Err))
		return -1, err
	}

	return re.LastInsertID, nil
}

func (u *Users) IncScore(ctx context.Context, discordID string) error {
	sp, ctx := opentracing.StartSpanFromContext(ctx, "users.inc.score")
	defer sp.Finish()
	sp.LogFields(splog.String("discord.id", discordID))

	re, err := u.conn.WriteOne(gorqlite.NewPreparedStatement("UPDATE users SET score = score + 1 WHERE discord_id=%s").Bind(discordID))
	if err != nil {
		sp.LogFields(splog.Error(err))
	}

	if re.Err != nil {
		sp.LogFields(splog.Error(re.Err))
		return re.Err
	}

	return nil
}

type User struct {
	ID        int64  `json:"id"`
	DiscordID string `json:"discord_id"`
	Score     int64  `json:"score"`
}

func (u *Users) Top10(ctx context.Context) ([]User, error) {
	sp, ctx := opentracing.StartSpanFromContext(ctx, "users.top10")
	defer sp.Finish()

	qr, err := u.conn.QueryOne("SELECT id, discord_id, score FROM users WHERE score > 0 ORDER BY score DESC LIMIT 10")
	if err != nil {
		sp.LogFields(splog.Error(err))
	}

	if qr.Err != nil {
		sp.LogFields(splog.Error(qr.Err))
		return nil, qr.Err
	}

	var result []User

	if qr.NumRows() == 0 {
		sp.LogFields(splog.Error(sql.ErrNoRows))
		return nil, sql.ErrNoRows
	}

	for qr.Next() {
		var u User
		err = qr.Scan(&u.ID, &u.DiscordID, &u.Score)
		if err != nil {
			sp.LogFields(splog.Error(err))
			return nil, err
		}

		result = append(result, u)
	}

	return result, nil
}