package tape

import "fmt"
import "bytes"
import "testing"
import "reflect"
import tu "git.tebibyte.media/sashakoshka/hopp/internal/testutil"

func TestEncodeAnyInt(test *testing.T) {
	err := testEncodeAny(test, uint8(0xCA), LI.WithCN(0), tu.S(0xCA))
	if err != nil { test.Fatal(err) }
	err = testEncodeAny(test, 400, LI.WithCN(3), tu.S(
		0, 0, 0x1, 0x90,
	))
	if err != nil { test.Fatal(err) }
}

func TestEncodeAnyTable(test *testing.T) {
	err := testEncodeAny(test, map[uint16] any {
		0xF3B9: 1,
		0x0102: 2,
		0x0000: "hi!",
		0xFFFF: []uint16 { 0xBEE5, 0x7777 },
		0x1234: [][]uint16 { []uint16 { 0x5 }, []uint16 { 0x17, 0xAAAA} },
	}, KTV.WithCN(0), tu.S(5).AddVar(
		[]byte {
			0xF3, 0xB9,
			byte(LI.WithCN(3)),
			0, 0, 0, 1,
		},
		[]byte {
			0x01, 0x02,
			byte(LI.WithCN(3)),
			0, 0, 0, 2,
		},
		[]byte {
			0, 0,
			byte(SBA.WithCN(3)),
			'h', 'i', '!',
		},
		[]byte {
			0xFF, 0xFF,
			byte(OTA.WithCN(0)), 2, byte(LI.WithCN(1)),
			0xBE, 0xE5, 0x77, 0x77,
		},
		[]byte {
			0x12, 0x34,
			byte(OTA.WithCN(0)), 2, byte(OTA.WithCN(0)),
			1, byte(LI.WithCN(1)),
			0, 0x5,
			2, byte(LI.WithCN(1)),
			0,    0x17,
			0xAA, 0xAA,
		},
	))
	if err != nil { test.Fatal(err) }
}

func TestEncodeDecodeAnyMap(test *testing.T) {
	err := testEncodeDecodeAny(test, map[uint16] any {
		0xF3B9: 1,
		0x0102: 2,
		0x0000: "hi!",
		0xFFFF: []uint16 { 0xBEE5, 0x7777 },
		0x1234: [][]uint16 { []uint16 { 0x5 }, []uint16 { 0x17, 0xAAAA} },
	}, nil)
	if err != nil { test.Fatal(err) }
}

func TestPeekSlice(test *testing.T) {
	buffer := bytes.NewBuffer([]byte {
		2, byte(OTA.WithCN(3)),
		0, 0, 0, 1, byte(LI.WithCN(1)),
		0, 0x5,
		2, byte(LI.WithCN(1)),
		0,    0x17,
		0xAA, 0xAA,
	})
	decoder := NewDecoder(buffer)

	elem, dimension, err := peekSlice(decoder, OTA.WithCN(0))
	if err != nil { test.Fatal(err) }
	if elem != LI.WithCN(1) {
		test.Fatalf("wrong element tag: %v %02X", elem, byte(elem))
	}
	if got, correct := dimension, 2; got != correct {
		test.Fatalf("wrong dimension: %d != %d", got, correct)
	}
}

func TestPeekSliceOnce(test *testing.T) {
	buffer := bytes.NewBuffer([]byte {
		2, byte(OTA.WithCN(3)),
		0, 0, 0, 1, byte(LI.WithCN(1)),
		0, 0x5,
		2, byte(LI.WithCN(1)),
		0,    0x17,
		0xAA, 0xAA,
	})
	decoder := NewDecoder(buffer)

	test.Log("--- stage 1")
	elem, populated, n, err := peekSliceOnce(decoder, OTA.WithCN(0), 0)
	if err != nil { test.Fatal(err) }
	if elem != OTA.WithCN(3) {
		test.Fatal("wrong element tag:", elem)
	}
	if !populated {
		test.Fatal("wrong populated:", populated)
	}
	if got, correct := n, 2; got != correct {
		test.Fatalf("wrong n: %d != %d", got, correct)
	}
	
	test.Log("--- stage 2")
	elem, populated, n, err = peekSliceOnce(decoder, elem, n)
	if err != nil { test.Fatal(err) }
	if elem != LI.WithCN(1) {
		test.Fatal("wrong element tag:", elem)
	}
	if !populated {
		test.Fatal("wrong populated:", populated)
	}
	if got, correct := n, 7; got != correct {
		test.Fatalf("wrong n: %d != %d", got, correct)
	}
}

func encAny(value any) ([]byte, Tag, int, error) {
	tag, err := TagAny(value)
	if err != nil { return nil, 0, 0, err }
	buffer := bytes.Buffer { }
	encoder := NewEncoder(&buffer)
	n, err := EncodeAny(encoder, value, tag)
	if err != nil { return nil, 0, n, err }
	encoder.Flush()
	return buffer.Bytes(), tag, n, nil
}

func decAny(data []byte) (Tag, any, int, error) {
	destination := map[uint16] any { }
	tag, err := TagAny(destination)
	if err != nil { return 0, nil, 0, err }
	n, err := DecodeAny(NewDecoder(bytes.NewBuffer(data)), &destination, tag)
	if err != nil { return 0, nil, n, err }
	return tag, destination, n, nil
}

func testEncodeAny(test *testing.T, value any, correctTag Tag, correctBytes tu.Snake) error {
	bytes, tag, n, err := encAny(value)
	if err != nil { return err }
	test.Log("n:      ", n)
	test.Log("tag:    ", tag)
	test.Log("got:    ", tu.HexBytes(bytes))
	test.Log("correct:", correctBytes)
	if tag != correctTag {
		return fmt.Errorf("tag not equal")
	}
	if ok, n := correctBytes.Check(bytes); !ok {
		return fmt.Errorf("bytes not equal: %d", n)
	}
	if n != len(bytes) {
		return fmt.Errorf("n not equal: %d != %d", n, len(bytes))
	}
	return nil
}

func testEncodeDecodeAny(test *testing.T, value, correctValue any) error {
	if correctValue == nil { 
		correctValue = value
	}

	test.Log("encoding...")
	bytes, tag, n, err := encAny(value)
	if err != nil { return err }
	test.Log("n:  ", n)
	test.Log("tag:", tag)
	test.Log("got:", tu.HexBytes(bytes))
	test.Log("decoding...", tag)
	if n != len(bytes) {
		return fmt.Errorf("n not equal: %d != %d", n, len(bytes))
	}
	
	_, decoded, n, err := decAny(bytes)
	if err != nil { return err }
	test.Log("got:    ", decoded)
	test.Log("correct:", correctValue)
	if !reflect.DeepEqual(decoded, correctValue) {
		return fmt.Errorf("values not equal")
	}
	if n != len(bytes) {
		return fmt.Errorf("n not equal: %d != %d", n, len(bytes))
	}
	return nil
}