package app

import (
	"fmt"
	"strings"
	"time"
)

func transportSystemdRunActionUnits(
	client TransportClient,
	action string,
	units []string,
	aggOut *[]string,
	aggErr *[]string,
) *transportBackendActionResult {
	for _, unit := range units {
		stdout, stderr, exitCode, err := transportRunCommand(transportBackendActionTimeout, "systemctl", action, unit)
		if s := strings.TrimSpace(stdout); s != "" {
			*aggOut = append(*aggOut, unit+": "+s)
		}
		if s := strings.TrimSpace(stderr); s != "" {
			*aggErr = append(*aggErr, unit+": "+s)
		}
		if (action == "start" || action == "restart") &&
			client.Kind == TransportClientSingBox &&
			transportSystemdUnitMissingError(stdout, stderr, exitCode, err) {
			appendTraceLineRateLimited(
				"transport",
				fmt.Sprintf("systemctl %s unit missing, trying auto-provision: client=%s unit=%s", action, client.ID, unit),
				20*time.Second,
			)
			provision := (transportSystemdBackend{}).Provision(client)
			if s := strings.TrimSpace(provision.Stdout); s != "" {
				*aggOut = append(*aggOut, "provision: "+s)
			}
			if s := strings.TrimSpace(provision.Stderr); s != "" {
				*aggErr = append(*aggErr, "provision: "+s)
			}
			if !provision.OK {
				msg := strings.TrimSpace(provision.Message)
				if msg == "" {
					msg = "auto-provision failed"
				}
				return &transportBackendActionResult{
					OK:        false,
					Code:      provision.Code,
					Message:   msg,
					ExitCode:  provision.ExitCode,
					Stdout:    strings.Join(*aggOut, "\n"),
					Stderr:    strings.Join(*aggErr, "\n"),
					Retryable: true,
				}
			}
			stdout, stderr, exitCode, err = transportRunCommand(transportBackendActionTimeout, "systemctl", action, unit)
			if s := strings.TrimSpace(stdout); s != "" {
				*aggOut = append(*aggOut, unit+": "+s)
			}
			if s := strings.TrimSpace(stderr); s != "" {
				*aggErr = append(*aggErr, unit+": "+s)
			}
		}
		if action == "stop" && transportSystemdStopMissingUnitNoop(stdout, stderr, exitCode, err) {
			appendTraceLineRateLimited(
				"transport",
				fmt.Sprintf("systemctl stop noop: client=%s unit=%s reason=unit-missing", client.ID, unit),
				15*time.Second,
			)
			continue
		}
		if err != nil || exitCode != 0 {
			msg := strings.TrimSpace(stderr)
			if msg == "" {
				msg = strings.TrimSpace(stdout)
			}
			if msg == "" {
				msg = fmt.Sprintf("systemctl %s %s failed", action, unit)
			}
			return &transportBackendActionResult{
				OK:        false,
				Code:      "TRANSPORT_BACKEND_ACTION_FAILED",
				Message:   msg,
				ExitCode:  exitCode,
				Stdout:    strings.Join(*aggOut, "\n"),
				Stderr:    strings.Join(*aggErr, "\n"),
				Retryable: action != "stop",
			}
		}
	}
	return nil
}