// time-sync's tools bundle (novox/hq to-be 42 Phase 1, research 026/05), and its step.
//
// Served by the node's runtime over MCP on stdio through the Go SDK (ADR 0188, ADR 0193) when it is
// started with no arguments. Started as `time-sync-tools retire <unit>…` it is the module's step,
// which the host runs once as root for every version of the bundle (timesync.go says why).
package main

import (
	"context"
	"fmt"
	"os"
	"strings"

	stdio "git.novox.be/novox/mesh-sdk/go"
)

// binaryName is what the build names this bundle's executable: the manifest's `binary`.
const binaryName = "time-sync-tools"

func bg() context.Context { return context.Background() }

func main() {
	m := ThisMachine()
	if len(os.Args) > 1 {
		if os.Args[1] != "retire" || len(os.Args) < 3 {
			fmt.Fprintf(os.Stderr, "usage: %s [retire <unit>…]\n", binaryName)
			os.Exit(2)
		}
		r, err := m.Retire(os.Args[2:], Wants, Dangling, os.Remove)
		if err != nil {
			fmt.Fprintln(os.Stderr, err)
			os.Exit(1)
		}
		fmt.Printf("disabled: %s; dangling links taken out: %s\n", orNone(r.Disabled), orNone(r.Removed))
		return
	}
	// An empty name serves as the module the runtime names (MESH_SERVED_MODULE): time-sync.
	if err := stdio.Serve("", tools(m)); err != nil {
		fmt.Fprintln(os.Stderr, err)
		os.Exit(1)
	}
}

func orNone(list []string) string {
	if len(list) == 0 {
		return "none"
	}
	return strings.Join(list, ", ")
}

func tools(m *Machine) []stdio.Tool {
	return []stdio.Tool{
		{
			Name: "time_sync_status",
			Description: "Whether the clock is synchronised and how well: NTP on, synchronised, timesyncd's unit state, the server " +
				"it uses, offset, delay and jitter in milliseconds, stratum and packet count (timedatectl timesync-status, with " +
				"its every line), and any other time daemon installed beside it. timesyncd not answering is said, not failed.",
			Input: schema(map[string]any{}),
			Run:   func(map[string]any) (any, error) { return m.Status() },
		},
		{
			Name: "time_sync_servers",
			Description: "The servers timesyncd uses (the one now, the configured, the fallback, the link's and the runtime's) " +
				"and every configuration file in the order it reads them with the NTP= and FallbackNTP= each sets; which file " +
				"decides, and a note when a drop-in sorting after the mesh's wins.",
			Input: schema(map[string]any{}),
			Run:   func(map[string]any) (any, error) { return m.Servers() },
		},
		{
			Name: "time_sync_sync_now",
			Description: "Restart timesyncd (sudo -n), which asks its server at once, and answer the status after up to ten " +
				"seconds of waiting for its first packet.",
			Input: schema(map[string]any{}),
			Run:   func(map[string]any) (any, error) { return m.SyncNow() },
		},
	}
}