package player

import (
	"context"
	"fmt"
	"log/slog"
	"time"

	"github.com/google/uuid"
	"gitlab.com/zephyrtronium/sq"
)

// Session is a session ID.
type Session = uuid.UUID

// InitSessions initializes an SQLite table relating player IDs to sessions.
func InitSessions(ctx context.Context, db Execer) error {
	_, err := db.Exec(ctx, initSessions)
	if err != nil {
		return fmt.Errorf("couldn't init sessions table: %w", err)
	}
	return nil
}

// StartSession creates a new 24-hour session for a player as of now.
func StartSession(ctx context.Context, db Execer, p ID, now time.Time) (Session, error) {
	id := uuid.New()
	ttl := now.Add(24 * time.Hour).Unix()
	_, err := db.Exec(ctx, `INSERT OR REPLACE INTO shotgun_session(player, id, ttl) VALUES (?, ?, ?)`, p, id, ttl)
	if err != nil {
		slog.ErrorContext(ctx, "couldn't start session", "player", p, "error", err.Error())
		return Session{}, fmt.Errorf("couldn't start session: %w", err)
	}
	slog.InfoContext(ctx, "session started", "player", p, "session", id, "now", now)
	return Session(id), nil
}

// FromSession gets the player ID associated with a session and updates the
// session to last 24 hours past now.
func FromSession(ctx context.Context, db RowQuerier, id Session, now time.Time) (ID, error) {
	ttl := now.Add(24 * time.Hour).Unix()
	var p ID
	err := db.QueryRow(ctx, `UPDATE shotgun_session SET ttl = ? WHERE id = ? AND ttl >= ? RETURNING player;`, ttl, id, now.Unix()).Scan(&p)
	switch err {
	case nil: // do nothing
	case sq.ErrNoRows:
		slog.WarnContext(ctx, "looked for missing session", "session", id, "now", now)
		return ID{}, fmt.Errorf("no such session")
	default:
		slog.ErrorContext(ctx, "couldn't get player from session", "session", id, "now", now, "error", err.Error())
		return ID{}, fmt.Errorf("couldn't get player from session: %w", err)
	}
	slog.InfoContext(ctx, "got player from session", "session", id, "player", p)
	return p, nil
}

// Logout deletes a session.
func Logout(ctx context.Context, db Execer, id Session) error {
	_, err := db.Exec(ctx, `DELETE FROM shotgun_session WHERE id = ?`, id)
	if err != nil {
		slog.ErrorContext(ctx, "couldn't logout", "session", id, "error", err.Error())
		return fmt.Errorf("couldn't logout: %w", err)
	}
	slog.InfoContext(ctx, "logged out", "session", id)
	return nil
}

const initSessions = `CREATE TABLE shotgun_session (
    id TEXT PRIMARY KEY,
    player TEXT NOT NULL UNIQUE,
    ttl INTEGER
) STRICT;`