package ids

import (
	"fmt"
	"testing"
	"testing/quick"
)

func ExampleMarshalString() {
	fmt.Print("\n")

	s := marshalString(9223372036854775807)
	fmt.Println(s)

	s = marshalString(19821031)
	fmt.Print(s)

	// Output:
	// 7ZZZZZZZZZZZZ
	// JWWF7
}

func ExampleUnmarshalString() {
	fmt.Print("\n")

	i, err := unmarshalString("7ZZZZZZZZZZZZ")
	if err != nil {
		fmt.Println(err)
	}
	fmt.Println(i)

	i, err = unmarshalString("JWWF7")
	if err != nil {
		fmt.Println(err)
	}
	fmt.Println(i)

	// Output:
	// 9223372036854775807
	// 19821031
}

// Positive int64 values should be isomorphic to encoded strings
// For any postive int64 value we should be able to encode it, decode it and have the same value
func TestIsomorphism(t *testing.T) {
	abs := func(i int64) int64 {
		if i < 0 {
			return i * -1
		}
		return i
	}

	absMarshalUnmarshal := func(i int64) int64 {
		// fmt.Println("DEBUG: ", i, abs(i))
		enc := marshalString(abs(i))
		dec, err := unmarshalString(enc)
		if err != nil {
			return -1
		}
		return dec
	}

	err := quick.CheckEqual(abs, absMarshalUnmarshal, nil)
	if err != nil {
		t.Error(err)
	}
}