package processbuilds

import (
	"context"
	"errors"
	"strings"
	"testing"

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

// Design 47, *The fingerprint handover*: the build of a daemon is read from its running process's environment and of a
// container from its configuration, narrowed by module; one started without the value, one not running and one the
// runtime cannot read each say why their build is unknown, never a guessed fingerprint.
func TestProcessBuildsAreReadFromTheRunningProcesses(t *testing.T) {
	fp := "src2:" + strings.Repeat("a", 64)
	d := &declaration.Declaration{Resources: []declaration.Resource{
		&declaration.Process{ID: "web.d", Type: declaration.TypeProcess, Module: "web", Name: "web-d"},
		&declaration.Process{ID: "old.d", Type: declaration.TypeProcess, Module: "old", Name: "old-d"},
		&declaration.Process{ID: "down.d", Type: declaration.TypeProcess, Module: "down", Name: "down-d"},
		&declaration.Container{ID: "db.c", Type: declaration.TypeContainer, Module: "db", Name: "db-c"},
		&declaration.Container{ID: "gone.c", Type: declaration.TypeContainer, Module: "gone", Name: "gone-c"},
		&declaration.Directory{ID: "web.dir", Type: declaration.TypeDirectory, Module: "web"},
	}}
	run := func(_ context.Context, name string, args ...string) (string, error) {
		switch {
		case name == "systemctl" && args[len(args)-1] == "web-d.service":
			return "MainPID=11\nActiveEnterTimestamp=Mon 2026-11-09 10:00:00 UTC\n", nil
		case name == "systemctl" && args[len(args)-1] == "old-d.service":
			return "MainPID=12\nActiveEnterTimestamp=\n", nil
		case name == "systemctl":
			return "MainPID=0\nActiveEnterTimestamp=\n", nil
		case name == "docker" && args[len(args)-1] == "db-c":
			return `["A=1","MESH_FINGERPRINT=` + fp + `"]` + "\t2026-11-09T10:00:00.5Z\n", nil
		}
		return "", errors.New("no such container")
	}
	environ := func(pid int) ([]byte, error) {
		if pid == 11 {
			return []byte("A=1\x00MESH_FINGERPRINT=" + fp + "\x00"), nil
		}
		return []byte("A=1\x00"), nil
	}
	r := Reader{Node: "n1", Run: run, Environ: environ}
	got := r.Read(context.Background(), d, "")
	by := map[string]string{}
	for _, p := range got.Processes {
		by[p.Module] = p.Fingerprint + "|" + p.Unknown
	}
	want := map[string]string{"web": fp + "|", "db": fp + "|",
		"old":  "|started before the node-engine handed MESH_FINGERPRINT, or without it",
		"down": "|the unit runs no process now", "gone": "|the container cannot be read: no such container"}
	if len(by) != len(want) || got.Node != "n1" {
		t.Fatalf("read %v, want %v", by, want)
	}
	for m, w := range want {
		if by[m] != w {
			t.Errorf("%s: %q, want %q", m, by[m], w)
		}
	}
	if got.Processes[0].Module != "db" || got.Processes[len(got.Processes)-1].Module != "web" || got.Processes[len(got.Processes)-1].Started == nil {
		t.Errorf("order or start time wrong: %+v", got.Processes)
	}
	if one := r.Read(context.Background(), d, "web"); len(one.Processes) != 1 || one.Processes[0].Process != "web-d.service" {
		t.Errorf("narrowed by module: %+v", one.Processes)
	}
	if none := r.Read(context.Background(), nil, ""); none.Error == "" || none.Processes == nil {
		t.Errorf("no declaration: %+v", none)
	}
}