package core

import (
	"sort"
	"testing"
	"time"
)

func TestNewUUID(t *testing.T) {
	id1 := NewUUID()
	id2 := NewUUID()
	if id1 == "" {
		t.Fatal("NewUUID returned empty string")
	}
	if id1 == id2 {
		t.Fatal("NewUUID returned duplicate UUIDs")
	}
}

func TestVal(t *testing.T) {
	v := Val("hello")
	if v.Contents != "hello" {
		t.Fatalf("expected contents 'hello', got %q", v.Contents)
	}
	if v.Type != ValueTypeUnspecified {
		t.Fatalf("expected type %q, got %q", ValueTypeUnspecified, v.Type)
	}
}

func TestVals(t *testing.T) {
	v := Vals("world")
	if v.Contents != "world" {
		t.Fatalf("expected contents 'world', got %q", v.Contents)
	}
	if v.Type != ValueTypeString {
		t.Fatalf("expected type %q, got %q", ValueTypeString, v.Type)
	}
}

func TestNewHeader(t *testing.T) {
	before := time.Now().UTC().Unix()
	h := NewHeader(ObjectTypeArtifact)
	after := time.Now().UTC().Unix()

	if h.ID == "" {
		t.Fatal("header ID is empty")
	}
	if h.Type != ObjectTypeArtifact {
		t.Fatalf("expected type %q, got %q", ObjectTypeArtifact, h.Type)
	}
	if h.Created < before || h.Created > after {
		t.Fatalf("Created timestamp %d not in range [%d, %d]", h.Created, before, after)
	}
	if h.Modified != h.Created {
		t.Fatalf("Modified (%d) should equal Created (%d)", h.Modified, h.Created)
	}
	if h.Meta == nil {
		t.Fatal("Meta should not be nil")
	}
}

func TestHeaderTouch(t *testing.T) {
	h := NewHeader(ObjectTypeNode)
	original := h.Modified
	// Ensure at least 1 second passes for timestamp change.
	time.Sleep(10 * time.Millisecond)
	h.Touch()
	if h.Modified < original {
		t.Fatalf("Touch should not decrease Modified: was %d, now %d", original, h.Modified)
	}
}

func TestMapFromList(t *testing.T) {
	list := []string{"alpha", "beta", "gamma"}
	m := MapFromList(list)
	if len(m) != 3 {
		t.Fatalf("expected 3 entries, got %d", len(m))
	}
	for _, s := range list {
		if !m[s] {
			t.Fatalf("expected %q in map", s)
		}
	}
}

func TestListFromMap(t *testing.T) {
	m := map[string]bool{"z": true, "a": true, "m": true}
	list := ListFromMap(m)
	if len(list) != 3 {
		t.Fatalf("expected 3 entries, got %d", len(list))
	}
	sort.Strings(list)
	expected := []string{"a", "m", "z"}
	for i, v := range list {
		if v != expected[i] {
			t.Fatalf("index %d: expected %q, got %q", i, expected[i], v)
		}
	}
}

func TestMapFromListEmpty(t *testing.T) {
	m := MapFromList(nil)
	if len(m) != 0 {
		t.Fatalf("expected empty map, got %d entries", len(m))
	}
}