//go:build integration

// Runs against a real Postgres with the dashboard API's migrations applied
// (the lobby limit is a trigger from migration 000020):
//
//	TEST_DB=postgres://... go test -tags integration ./internal/db/repos/settingsrepo
package settingsrepo

import (
	"context"
	"database/sql"
	"errors"
	"os"
	"sync"
	"testing"

	_ "github.com/jackc/pgx/v5/stdlib"
)

func testRepo(t *testing.T) (*Repo, int64) {
	t.Helper()
	dsn := os.Getenv("TEST_DB")
	if dsn == "" {
		t.Skip("TEST_DB not set")
	}
	db, err := sql.Open("pgx", dsn)
	if err != nil {
		t.Fatal(err)
	}
	t.Cleanup(func() { db.Close() })
	const guild = 4242
	if _, err := db.Exec(`DELETE FROM meeting_lobbies WHERE guild_id IN ($1, $2)`, guild, guild+1); err != nil {
		t.Fatal(err)
	}
	return NewRepo(db), guild
}

func TestMeetingLobbies(t *testing.T) {
	r, g := testRepo(t)
	ctx := context.Background()

	if ids, err := r.ListMeetingLobbies(ctx, g); err != nil || len(ids) != 0 {
		t.Fatalf("a fresh server has no lobbies: %v %v", ids, err)
	}

	for ch := int64(1); ch <= MaxMeetingLobbies; ch++ {
		added, err := r.AddMeetingLobby(ctx, g, ch)
		if err != nil || !added {
			t.Fatalf("adding lobby %d: added=%v err=%v", ch, added, err)
		}
	}
	if _, err := r.AddMeetingLobby(ctx, g, 99); !errors.Is(err, ErrMeetingLobbyLimit) {
		t.Errorf("an 11th lobby must hit the limit, got %v", err)
	}
	if added, err := r.AddMeetingLobby(ctx, g, 3); err != nil || added {
		t.Errorf("adding an existing lobby is a no-op even at the limit: added=%v err=%v", added, err)
	}
	if added, err := r.AddMeetingLobby(ctx, g+1, 99); err != nil || !added {
		t.Errorf("the limit is per server: added=%v err=%v", added, err)
	}

	if ok, _ := r.IsMeetingLobby(ctx, g, 7); !ok {
		t.Error("7 is a lobby")
	}
	if ok, _ := r.IsMeetingLobby(ctx, g, 99); ok {
		t.Error("99 isn't a lobby of this server (it is one of the other server's)")
	}

	if removed, err := r.RemoveMeetingLobby(ctx, g, 7); err != nil || !removed {
		t.Errorf("removing 7: removed=%v err=%v", removed, err)
	}
	if removed, _ := r.RemoveMeetingLobby(ctx, g, 7); removed {
		t.Error("7 was already removed")
	}
	if ok, _ := r.IsMeetingLobby(ctx, g, 7); ok {
		t.Error("7 is no longer a lobby")
	}
	if added, err := r.AddMeetingLobby(ctx, g, 99); err != nil || !added {
		t.Errorf("removing one makes room: added=%v err=%v", added, err)
	}

	ids, err := r.ListMeetingLobbies(ctx, g)
	if err != nil || len(ids) != MaxMeetingLobbies || ids[len(ids)-1] != 99 {
		t.Errorf("oldest first, newest last: %v %v", ids, err)
	}
}

// Two people adding a lobby at the same moment must not both fit under the limit.
func TestMeetingLobbiesConcurrent(t *testing.T) {
	r, g := testRepo(t)
	ctx := context.Background()
	for ch := int64(1); ch < MaxMeetingLobbies; ch++ {
		if _, err := r.AddMeetingLobby(ctx, g, ch); err != nil {
			t.Fatal(err)
		}
	}

	var wg sync.WaitGroup
	var mu sync.Mutex
	succeeded := 0
	for i := 0; i < 8; i++ {
		wg.Add(1)
		go func(ch int64) {
			defer wg.Done()
			if added, err := r.AddMeetingLobby(ctx, g, ch); err == nil && added {
				mu.Lock()
				succeeded++
				mu.Unlock()
			}
		}(int64(100 + i))
	}
	wg.Wait()
	if succeeded != 1 {
		t.Errorf("exactly one of the concurrent adds fits, %d did", succeeded)
	}
	if ids, _ := r.ListMeetingLobbies(ctx, g); len(ids) != MaxMeetingLobbies {
		t.Errorf("have %d lobbies, want %d", len(ids), MaxMeetingLobbies)
	}
}