package birdwhisperer

import (
	"testing"
)

func TestPruningChunkRecord(t *testing.T) {
	bw := NewBirdWhisperer()

	incompleteMessageNotExpired := ReconstructedMessage{
		ReceivedTime:   195_000, // "Just started"
		CompletedTime:  0,
		NumChunks:      2,
		ReceivedChunks: 1,
	}
	incompleteMessageExpired := ReconstructedMessage{
		ReceivedTime:   100, // Started a long time ago
		CompletedTime:  0,
		NumChunks:      2,
		ReceivedChunks: 1,
	}
	completeMessageNotExpired := ReconstructedMessage{
		ReceivedTime:   100,
		CompletedTime:  199_000, // "Just finished"
		NumChunks:      2,
		ReceivedChunks: 2,
	}
	completeMessageExpired := ReconstructedMessage{
		ReceivedTime:   100,
		CompletedTime:  10_000, // Finished a long time ago
		NumChunks:      2,
		ReceivedChunks: 2,
	}

	bw.ChunkRecord[0] = incompleteMessageNotExpired
	bw.ChunkRecord[1] = incompleteMessageExpired
	bw.ChunkRecord[2] = completeMessageNotExpired
	bw.ChunkRecord[3] = completeMessageExpired

	bw.PruneChunkRecord(200_000)

	if _, exists := bw.ChunkRecord[0]; !exists {
		t.Errorf("Pruned an incomplete message that hasn't expired yet")
	}

	if _, exists := bw.ChunkRecord[1]; exists {
		t.Errorf("Didn't prune an incomplete message that expired")
	}
	if _, exists := bw.ChunkRecord[2]; !exists {
		t.Errorf("Pruned an complete message that hasn't expired yet")
	}
	if _, exists := bw.ChunkRecord[3]; exists {
		t.Errorf("Didn't prune an incomplete message that expired")
	}
}

func TestChunkMessageSingleChunk(t *testing.T) {
	messageId := uint16(123)
	message := make([]byte, CHUNK_MAX_LENGTH-1)
	chunks := ChunkMessage(message, messageId)

	if len(chunks) != 1 {
		t.Errorf("A message that should be 1 chunk is actually %d chunks", len(chunks))
	}
}

func TestChunkMessageMultipleChunks(t *testing.T) {
	messageId := uint16(123)
	message := make([]byte, CHUNK_MAX_LENGTH*2)
	chunks := ChunkMessage(message, messageId)

	if len(chunks) != 2 {
		t.Errorf("A message that should be 2 chunks is actually %d chunks", len(chunks))
	}
}

func TestChunkMessageMultipleChunksAndSome(t *testing.T) {
	messageId := uint16(123)
	extraDataLen := 1
	message := make([]byte, CHUNK_MAX_LENGTH*2+extraDataLen)
	chunks := ChunkMessage(message, messageId)

	if len(chunks) != 3 {
		t.Errorf("A message that should be 3 chunks is actually %d chunks", len(chunks))
	}

	const expectedChunkLength = CHUNK_MAX_LENGTH + CHUNK_V1_HEADER_LENGTH
	if len(chunks[0]) != expectedChunkLength {
		t.Errorf("Chunk 0 should be %d, is %d", expectedChunkLength, len(chunks[0]))
	}
	if len(chunks[1]) != expectedChunkLength {
		t.Errorf("Chunk 1 should be %d, is %d", expectedChunkLength, len(chunks[1]))
	}
	if len(chunks[2]) != extraDataLen+CHUNK_V1_HEADER_LENGTH {
		t.Errorf("Chunk 2 should be %d, is %d", extraDataLen+CHUNK_V1_HEADER_LENGTH, len(chunks[2]))
	}
}