package rpsrepo

import (
	"context"
	"database/sql"
)

type Repo struct {
	db *sql.DB
}

func NewRepo(db *sql.DB) *Repo {
	return &Repo{db: db}
}

func (r *Repo) GetScore(ctx context.Context, guildID int64, userID int64) (int, bool, error) {
	var score int
	err := r.db.QueryRowContext(ctx, `
		SELECT score
		FROM rps
		WHERE guild_id = $1 AND user_id = $2
	`, guildID, userID).Scan(&score)
	if err == sql.ErrNoRows {
		return 0, false, nil
	}
	if err != nil {
		return 0, false, err
	}
	return score, true, nil
}

func (r *Repo) SetScore(ctx context.Context, guildID int64, userID int64, score int) error {
	_, err := r.db.ExecContext(ctx, `
		INSERT INTO rps (guild_id, user_id, score)
		VALUES ($1, $2, $3)
		ON CONFLICT (guild_id, user_id)
		DO UPDATE SET score = EXCLUDED.score
	`, guildID, userID, score)
	return err
}

type ScoreEntry struct {
	UserID int64
	Score  int
}

func (r *Repo) TopScores(ctx context.Context, guildID int64, limit int) ([]ScoreEntry, error) {
	if limit <= 0 {
		limit = 10
	}
	rows, err := r.db.QueryContext(ctx, `
		SELECT user_id, score
		FROM rps
		WHERE guild_id = $1
		ORDER BY score DESC, user_id ASC
		LIMIT $2
	`, guildID, limit)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	out := make([]ScoreEntry, 0, limit)
	for rows.Next() {
		var e ScoreEntry
		if err := rows.Scan(&e.UserID, &e.Score); err != nil {
			return nil, err
		}
		out = append(out, e)
	}
	if err := rows.Err(); err != nil {
		return nil, err
	}
	return out, nil
}