package main

import (
	"bytes"
	"errors"
	"strings"
	"testing"
	"time"

	"github.com/novox/mesh-controller/internal/conditions"
	"github.com/novox/mesh-controller/internal/inventory"
	"github.com/novox/mesh-controller/internal/link"
)

// A hand-over's line is judged before anything is asked (novox/hq issue 356): a node's name and the directory's
// absolute path exactly as the engine states it — no `..`, no doubled or trailing separator, nothing relative.
func TestAHandOverLineIsJudgedBeforeItIsAsked(t *testing.T) {
	for _, args := range [][]string{
		{},
		{"laptop"},
		{"laptop", "/srv/notes", "extra"},
		{"", "/srv/notes"},
		{"--node", "/srv/notes"},
		{"laptop", "srv/notes"},
		{"laptop", "/srv/../etc"},
		{"laptop", "/srv//notes"},
		{"laptop", "/srv/notes/"},
		{"laptop", "/srv/notes/."},
	} {
		if _, _, err := handOverLine(args); err == nil {
			t.Errorf("%q was taken", args)
		}
	}
	node, path, err := handOverLine([]string{"laptop", "/srv/notes"})
	if err != nil || node != "laptop" || path != "/srv/notes" {
		t.Fatalf("read as %q %q %v", node, path, err)
	}
}

// Who hands over is the line's caller in the words every verb's caller is recorded in — the operator through
// mesh-cli — or the controller's terminal when nobody is named.
func TestAHandOverNamesWhoAsked(t *testing.T) {
	t.Setenv(link.CallerVar, " jo through mesh-cli on anchor ")
	if by := handOverBy(); by != "jo through mesh-cli on anchor" {
		t.Fatalf("by %q", by)
	}
	t.Setenv(link.CallerVar, "")
	if by := handOverBy(); by != "the controller's terminal" {
		t.Fatalf("by %q", by)
	}
}

// **A hand-over is the controller's terminal's alone** (novox/hq issue 356, ADR 0266): through any verb, and
// through mesh-cli outside the terminal, `node hand-over` is refused and nothing runs — at the next apply root
// gives the directory to the account the module declares, and whoever may call a verb includes agents.
func TestAHandOverIsRefusedThroughEveryVerb(t *testing.T) {
	line := []string{"node", "hand-over", "laptop", "/srv/notes"}
	if err := terminalOnly(line); err == nil {
		t.Fatal("node hand-over passed as a verb's line")
	}
	if _, err := argvFor("command", map[string]any{"command": "node hand-over laptop /srv/notes"}); err == nil {
		t.Fatal("the command verb composed node hand-over")
	}
	if _, err := ordinaryLine(line); err == nil {
		t.Fatal("node hand-over composed as an ordinary mesh-cli line")
	}
	if _, err := argvFor("node", map[string]any{"node": "laptop", "hand-over": "/srv/notes"}); err == nil {
		t.Fatal("the node verb composed a hand-over")
	}
}

// The condition's words are plain and name no machine's binary; the operator's line, with the node and the path
// (novox/hq ADR 0272), is in the summary the module's health gives (moduleHealthWord) and in the evidence.
func TestTheUsedAsFoundConditionNamesTheOperatorsLine(t *testing.T) {
	rs := []inventory.ResourceHealth{foundDirectory("notes", time.Now().Add(-24*time.Hour))}
	o := usedAsFoundObservation("notes", "laptop", "notes on laptop uses notes.data as found", rs)
	if strings.Contains(o.Needs, "mesh-host") || strings.Contains(o.Explanation, "mesh-host") ||
		!strings.Contains(o.Needs, "control-node") {
		t.Fatalf("the condition's words: %q %q", o.Needs, o.Explanation)
	}
	if why, ok := conditions.PlainWords(conditions.Words{Headline: o.Headline, Explanation: o.Explanation, Needs: o.Needs,
		Resolved: o.Resolved}, "laptop"); !ok {
		t.Fatalf("not plain: %s", why)
	}
	f := gateFacts{now: time.Now(), health: map[string]inventory.NodeHealth{"laptop": {Node: "laptop", HeardAt: time.Now(),
		Resources: rs}}}
	h, why := moduleHealthWord("notes", "laptop", time.Now().Add(-time.Hour), f)
	if h != healthPerson || !strings.Contains(why, "`nox node hand-over laptop <directory>` on the control-node") ||
		strings.Contains(why, "mesh-host") || strings.Contains(why, "/srv/") {
		t.Fatalf("the module's health reads %v %q; want the operator's line", h, why)
	}
}

// **Nothing is asked of a node the mesh does not know, and the engine's refusal is the command's failure**
// (review of issue 356): a refused hand-over never exits as a success.
func TestAHandOverAsksOnlyAKnownNodeAndFailsOnARefusal(t *testing.T) {
	t.Setenv(link.CallerVar, "jo through mesh-cli on anchor")
	asked := 0
	ask := func(answer link.HandOverAnswer) func(node, path, by string) (link.HandOverAnswer, error) {
		return func(node, path, by string) (link.HandOverAnswer, error) {
			asked++
			if node != "laptop" || path != "/srv/notes" || by != "jo through mesh-cli on anchor" {
				t.Fatalf("asked %q %q %q", node, path, by)
			}
			return answer, nil
		}
	}
	unknown := func(string) error { return errors.New("no node called laptop") }
	known := func(string) error { return nil }
	var out bytes.Buffer
	err := handOverAsked([]string{"laptop", "/srv/notes"}, unknown, ask(link.HandOverAnswer{Said: "x"}), &out)
	if err == nil || asked != 0 || !strings.Contains(err.Error(), "nothing was asked") {
		t.Fatalf("an unknown node: %v, asked %d", err, asked)
	}
	err = handOverAsked([]string{"laptop", "/srv/../etc"}, known, ask(link.HandOverAnswer{Said: "x"}), &out)
	if err == nil || asked != 0 {
		t.Fatalf("a refused line was asked: %v, asked %d", err, asked)
	}
	err = handOverAsked([]string{"laptop", "/srv/notes"}, known,
		ask(link.HandOverAnswer{Refused: "/srv/notes is not used as found; nothing was handed over"}), &out)
	if err == nil || !strings.Contains(err.Error(), "laptop refused: /srv/notes is not used as found") || out.Len() != 0 {
		t.Fatalf("a refusal: %v, printed %q", err, out.String())
	}
	err = handOverAsked([]string{"laptop", "/srv/notes"}, known, ask(link.HandOverAnswer{Said: "handed over"}), &out)
	if err != nil || !strings.HasPrefix(out.String(), "handed over\n") || !strings.Contains(out.String(), "`nox push laptop`") {
		t.Fatalf("a record: %v, printed %q", err, out.String())
	}
	failing := func(string, string, string) (link.HandOverAnswer, error) {
		return link.HandOverAnswer{}, errors.New("no engine")
	}
	if err := handOverAsked([]string{"laptop", "/srv/notes"}, known, failing, &out); err == nil {
		t.Fatal("an ask that failed was a success")
	}
}

// The setuid search's line asks only a known node, one name and nothing else, and fails on a refusal
// (novox/hq issue 361).
func TestASetuidSearchAsksOnlyAKnownNodeAndFailsOnARefusal(t *testing.T) {
	t.Setenv(link.CallerVar, "jo through mesh-cli on anchor")
	asked := 0
	ask := func(answer link.HandOverAnswer) func(node, by string) (link.HandOverAnswer, error) {
		return func(node, by string) (link.HandOverAnswer, error) {
			asked++
			if node != "novox" || by != "jo through mesh-cli on anchor" {
				t.Fatalf("asked %q %q", node, by)
			}
			return answer, nil
		}
	}
	known := func(string) error { return nil }
	var out bytes.Buffer
	for _, args := range [][]string{nil, {"novox", "extra"}, {"-x"}} {
		if err := setuidSearchAsked(args, known, ask(link.HandOverAnswer{Said: "x"}), &out); err == nil || asked != 0 {
			t.Fatalf("%v was asked: %v", args, err)
		}
	}
	if err := setuidSearchAsked([]string{"novox"}, func(string) error { return errors.New("no node called novox") },
		ask(link.HandOverAnswer{Said: "x"}), &out); err == nil || asked != 0 {
		t.Fatalf("an unknown node: %v", err)
	}
	if err := setuidSearchAsked([]string{"novox"}, known, ask(link.HandOverAnswer{Refused: "no; no search was started"}),
		&out); err == nil || !strings.Contains(err.Error(), "novox refused") || out.Len() != 0 {
		t.Fatalf("a refusal: %v, printed %q", err, out.String())
	}
	if err := setuidSearchAsked([]string{"novox"}, known, ask(link.HandOverAnswer{Said: "a new search starts"}),
		&out); err != nil || !strings.HasPrefix(out.String(), "a new search starts\n") {
		t.Fatalf("a start: %v, printed %q", err, out.String())
	}
}

// The directory judgement's line asks only a known node, one name and nothing else, fails on a refusal, and says it
// changed nothing (novox/hq issue 358).
func TestADirectoryJudgementAsksOnlyAKnownNodeAndSaysItIsReadOnly(t *testing.T) {
	t.Setenv(link.CallerVar, "jo through mesh-cli on anchor")
	asked := 0
	ask := func(answer link.HandOverAnswer) func(node, by string) (link.HandOverAnswer, error) {
		return func(node, by string) (link.HandOverAnswer, error) {
			asked++
			if node != "novox" || by != "jo through mesh-cli on anchor" {
				t.Fatalf("asked %q %q", node, by)
			}
			return answer, nil
		}
	}
	known := func(string) error { return nil }
	var out bytes.Buffer
	for _, args := range [][]string{nil, {"novox", "extra"}, {"-x"}} {
		if err := judgeDirectoriesAsked(args, known, ask(link.HandOverAnswer{Said: "x"}), &out); err == nil || asked != 0 {
			t.Fatalf("%v was asked: %v", args, err)
		}
	}
	if err := judgeDirectoriesAsked([]string{"novox"}, func(string) error { return errors.New("no node called novox") },
		ask(link.HandOverAnswer{Said: "x"}), &out); err == nil || asked != 0 {
		t.Fatalf("an unknown node: %v", err)
	}
	if err := judgeDirectoriesAsked([]string{"novox"}, known, ask(link.HandOverAnswer{Refused: "no; nothing was judged"}),
		&out); err == nil || !strings.Contains(err.Error(), "novox refused") || out.Len() != 0 {
		t.Fatalf("a refusal: %v, printed %q", err, out.String())
	}
	said := "2 directories declared: 1 placed, 1 would be refused\n/var/lib/a: placed\n/var/lib/b: would be refused: …"
	if err := judgeDirectoriesAsked([]string{"novox"}, known, ask(link.HandOverAnswer{Said: said}), &out); err != nil ||
		out.String() != "novox (read-only: nothing on novox was changed)\n"+said+"\n" {
		t.Fatalf("a judgement: %v, printed %q", err, out.String())
	}
}

// The judgement is a seat verb an agent may call — it reads, and changes nothing on the node — and runs exactly
// `node judge-directories <node>` (novox/hq issue 358).
func TestTheDirectoryJudgementIsAVerbThatOnlyReads(t *testing.T) {
	argv, err := argvFor("judge-directories", map[string]any{"node": "novox"})
	if err != nil || strings.Join(argv, " ") != "node judge-directories novox" {
		t.Fatalf("the verb runs %v, %v", argv, err)
	}
	if _, err := argvFor("judge-directories", map[string]any{}); err == nil {
		t.Fatal("the verb ran with no node")
	}
	if !readingVerbs["judge-directories"] {
		t.Fatal("the judgement is not counted a reading verb")
	}
}