package identity

import (
	"reflect"
	"strings"
	"sync"
	"testing"

	"gitea.maximumdirect.net/eric/notarius/internal/modules/dnd"
)

func TestNormalizeDisplayOnlyChangesWhitespace(t *testing.T) {
	if got := NormalizeDisplay("  O’Rin\u2003Thorn  "); got != "O’Rin Thorn" {
		t.Fatalf("NormalizeDisplay() = %q", got)
	}
}

func TestDeriveIDAndIDSyntax(t *testing.T) {
	got := DeriveID("  Mira\u2003Thorn ")
	const want = "npc:sha256:35ba5f679aee69e07ae3bd65c44278f29539d5dc9bb5225db1c0060555b23221"
	if Policy != "dnd.npc_registry.identity.v1" || IdentityPolicy != Policy {
		t.Fatalf("identity policy = %q/%q", Policy, IdentityPolicy)
	}
	if len(got) != len("npc:sha256:")+64 || !strings.HasPrefix(got, "npc:sha256:") || !IsValidID(got) {
		t.Fatalf("DeriveID() = %q, want exact NPC ID syntax", got)
	}
	if got != want {
		t.Fatalf("DeriveID() = %q, want SHA-256 of compact JSON [policy, comparison_name]", got)
	}
	if got != DeriveID("Mira Thorn") || got != IDFor("Mira Thorn") {
		t.Fatal("DeriveID() is not deterministic across equivalent names")
	}
	if DeriveID(" \u2003 ") != "" {
		t.Fatal("empty identity produced an ID")
	}
	for _, invalid := range []string{"", "npc:sha256:", "npc:sha256:ABC", "npc:sha256:" + strings.Repeat("0", 63), "npc:sha256:" + strings.Repeat("0", 65)} {
		if IsValidID(invalid) {
			t.Fatalf("IsValidID(%q) = true, want false", invalid)
		}
	}
}

func TestIdentityFunctionsAreSafeForConcurrentUse(t *testing.T) {
	const workers = 32
	var group sync.WaitGroup
	for i := 0; i < workers; i++ {
		group.Add(1)
		go func() {
			defer group.Done()
			for j := 0; j < 100; j++ {
				if !IsValidID(DeriveID("Mira Thorn")) {
					t.Errorf("derived ID failed syntax check")
					return
				}
			}
		}()
	}
	group.Wait()
}

func TestValidateRegistryReportsIdentityCollisionCategories(t *testing.T) {
	validID := DeriveID("Mira Thorn")
	npcs := []dnd.NPC{
		{ID: validID, Name: "Mira Thorn"},
		{ID: validID, Name: "Mira Thorn"},
	}
	before := append([]dnd.NPC(nil), npcs...)
	issues := ValidateRegistry(npcs)
	if !reflect.DeepEqual(npcs, before) {
		t.Fatal("ValidateRegistry() mutated its input")
	}
	want := map[IssueCode]bool{
		IssueDuplicateCanonical: false,
		IssueDuplicateID:        false,
	}
	for _, issue := range issues {
		if _, ok := want[issue.Code]; ok {
			want[issue.Code] = true
		}
	}
	for code, found := range want {
		if !found {
			t.Errorf("ValidateRegistry() did not report %s", code)
		}
	}
}

func TestValidateRegistryReportsIDProblems(t *testing.T) {
	issues := ValidateRegistry([]dnd.NPC{{ID: "bad", Name: "Mira Thorn"}, {ID: DeriveID("Mira Thorn"), Name: "Other Name"}})
	seen := map[IssueCode]bool{}
	for _, issue := range issues {
		seen[issue.Code] = true
	}
	if !seen[IssueInvalidID] || !seen[IssueIDMismatch] {
		t.Fatalf("ValidateRegistry() issues = %#v, want invalid and mismatched ID issues", issues)
	}
}