package app

import (
	"errors"
	"log"
	"net"
	"net/http"
	"os"
	"path/filepath"
)

func startServers(cfg Config, handler http.Handler) ([]*http.Server, func(), error) {
	var servers []*http.Server
	cleanup := func() {}

	if cfg.ListenAddr != "" {
		srv := &http.Server{Addr: cfg.ListenAddr, Handler: handler}
		servers = append(servers, srv)
		go func() {
			if err := srv.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
				log.Printf("tcp server error: %v", err)
			}
		}()
	}

	if cfg.UnixSocketPath != "" {
		if err := os.MkdirAll(filepath.Dir(cfg.UnixSocketPath), 0o755); err != nil {
			return nil, cleanup, err
		}
		_ = os.Remove(cfg.UnixSocketPath)
		ln, err := net.Listen("unix", cfg.UnixSocketPath)
		if err != nil {
			return nil, cleanup, err
		}
		if err := os.Chmod(cfg.UnixSocketPath, 0o666); err != nil {
			return nil, cleanup, err
		}

		srv := &http.Server{Handler: handler}
		servers = append(servers, srv)
		go func() {
			if err := srv.Serve(ln); err != nil && !errors.Is(err, http.ErrServerClosed) {
				log.Printf("unix server error: %v", err)
			}
		}()
		cleanup = func() {
			_ = ln.Close()
			_ = os.Remove(cfg.UnixSocketPath)
		}
	}

	if len(servers) == 0 {
		return nil, cleanup, errors.New("no listeners configured, set LISTEN_ADDR and/or UNIX_SOCKET_PATH")
	}
	return servers, cleanup, nil
}