package cache

import (
	"testing"
	"time"
)

func TestCache(t *testing.T) {
	key := "test"

	c := New()

	t.Log("simple put and get")

	value := "foo"

	c.Put(key, value)

	if n := c.Count(); n != 1 {
		t.Fatalf("Expected %d entries in the cache, got %d", 1, n)
	}

	val, ok := c.Get(key)
	if !ok {
		t.Fatalf("Expected cache to have an entry for key %q, but it did not", key)
	}

	val2, ok := val.(string)
	if !ok {
		t.Fatalf("Expected '%v' to have type string, but it has type %T", val, val)
	}

	if val2 != value {
		t.Fatalf("Expected '%v' to equal 'foo', but it does not", val2)
	}

	t.Log("Using the same key overwrites the value")

	value = "bar"

	c.Put(key, value)

	if n := c.Count(); n != 1 {
		t.Fatalf("Expected %d entries in the cache, got %d", 1, n)
	}

	val, ok = c.Get(key)
	if !ok {
		t.Fatalf("Expected cache to have an entry for key %q, but it did not", key)
	}

	val2, ok = val.(string)
	if !ok {
		t.Fatalf("Expected '%v' to have type string, but it has type %T", val, val)
	}

	if val2 != value {
		t.Fatalf("Expected '%v' to equal 'foo', but it does not", val2)
	}

	t.Log("It should tell if the cache is missed")

	val, ok = c.Get("does-not-exist")
	if ok {
		t.Fatalf("Expected cache to not have an entry for key %q, but it did", key)
	}

	if val != nil {
		t.Fatalf("Expected '%v' to be nil, but it was not", val2)
	}
}

func TestCacheTTL(t *testing.T) {
	key := "test"
	value := "foo"

	c := New()

	t.Log("Simple put and get a non-expired entry")

	c.PutTTL(key, value, 1*time.Hour)

	if n := c.Count(); n != 1 {
		t.Fatalf("Expected %d entries in the cache, got %d", 1, n)
	}

	_, ok := c.Get(key)
	if !ok {
		t.Fatalf("Expected cache to have an entry for key %q, but it did not", key)
	}

	t.Log("Simple put and get a 0 TTL")

	c.PutTTL(key, value, 0)

	if n := c.Count(); n != 1 {
		t.Fatalf("Expected %d entries in the cache, got %d", 1, n)
	}

	_, ok = c.Get(key)
	if !ok {
		t.Fatalf("Expected cache to have an entry for key %q, but it did not", key)
	}

	t.Log("Simple put and get an expired entry")

	c.PutTTL(key, value, -1*time.Hour)

	if n := c.Count(); n != 1 {
		t.Fatalf("Expected %d entries in the cache, got %d", 1, n)
	}

	_, ok = c.Get(key)
	if ok {
		t.Fatalf("Expected cache to not have an entry for key %q, but it did", key)
	}

	if n := c.Count(); n != 0 {
		t.Fatalf("Expected %d entries in the cache, got %d", 0, n)
	}
}

func TestCacheDel(t *testing.T) {
	key := "test"
	value := "foo"

	c := New()

	c.Put(key, value)

	if n := c.Count(); n != 1 {
		t.Fatalf("Expected %d entries in the cache, got %d", 1, n)
	}

	t.Log("Delete an existing key from the cache")

	c.Del(key)

	if n := c.Count(); n != 0 {
		t.Fatalf("Expected %d entries in the cache, got %d", 0, n)
	}

	c.Put(key, value)

	if n := c.Count(); n != 1 {
		t.Fatalf("Expected %d entries in the cache, got %d", 1, n)
	}

	t.Log("Delete an existing key from the cache")

	c.Del("does-not-exist")

	if n := c.Count(); n != 1 {
		t.Fatalf("Expected %d entries in the cache, got %d", 1, n)
	}
}