package layer_test

import (
	"os"
	"path/filepath"
	"testing"

	"github.com/netkingdom/flex-auth/internal/layer"
)

func writeRepo(t *testing.T, root, name, intent, declFile string) {
	t.Helper()
	dir := filepath.Join(root, name)
	if err := os.MkdirAll(dir, 0o755); err != nil {
		t.Fatal(err)
	}
	if intent != "" {
		body := "---\nlayer: " + intent + "\nrole: PDP\n---\n\n# x\n"
		if err := os.WriteFile(filepath.Join(dir, "INTENT.md"), []byte(body), 0o644); err != nil {
			t.Fatal(err)
		}
	}
	if declFile != "" {
		if err := os.WriteFile(filepath.Join(dir, "layer.yaml"), []byte("layer: "+declFile+"\n"), 0o644); err != nil {
			t.Fatal(err)
		}
	}
}

// The finding FLEX-WP-0030 B1 rests on: §11 accepts either form and does not
// say which governs when a repository carries both and they disagree.
func TestSurveyDetectsFormsDisagreeingWithinOneRepo(t *testing.T) {
	root := t.TempDir()
	writeRepo(t, root, "peer", "Engine", "engine")

	rows, err := layer.SurveyDeclarations(root, []string{"peer"})
	if err != nil {
		t.Fatal(err)
	}
	if len(rows) != 1 {
		t.Fatalf("rows = %d; want 1", len(rows))
	}
	if !rows[0].SelfDisagrees() {
		t.Fatal("Engine vs engine across the two §11 forms was not reported as disagreement")
	}
	if got := len(layer.SelfDisagreeing(rows)); got != 1 {
		t.Fatalf("SelfDisagreeing = %d; want 1", got)
	}
}

// Case is not folded: whether §3 is case-insensitive is the open question, and
// folding here would hide the finding rather than resolve it.
func TestSurveyDoesNotFoldCase(t *testing.T) {
	root := t.TempDir()
	writeRepo(t, root, "peer", "", "engine")

	rows, _ := layer.SurveyDeclarations(root, []string{"peer"})
	if rows[0].File.InVocabulary {
		t.Fatal(`"engine" was accepted into the §3 vocabulary; the survey must not fold case`)
	}
}

func TestSurveyReportsMissingDeclaration(t *testing.T) {
	root := t.TempDir()
	writeRepo(t, root, "silent", "", "")

	rows, _ := layer.SurveyDeclarations(root, []string{"silent"})
	if rows[0].Declared() {
		t.Fatal("a repository with neither form was reported as declared")
	}
	if got := layer.Undeclared(rows); len(got) != 1 || got[0] != "silent" {
		t.Fatalf("Undeclared = %v; want [silent]", got)
	}
}

// A single well-formed declaration must not be reported as disagreeing with
// itself — flex-auth is exactly this shape.
func TestSurveySingleFormIsNotDisagreement(t *testing.T) {
	root := t.TempDir()
	writeRepo(t, root, "solo", "Engine", "")

	rows, _ := layer.SurveyDeclarations(root, []string{"solo"})
	if rows[0].SelfDisagrees() {
		t.Fatal("a repository with only INTENT.md was reported as self-disagreeing")
	}
	if !rows[0].Intent.InVocabulary {
		t.Fatal(`"Engine" was rejected from the §3 vocabulary`)
	}
}