package be.simplenotes.domain

import be.simplenotes.persistence.repositories.NoteRepository
import be.simplenotes.types.ExportedNote
import kotlinx.serialization.builtins.ListSerializer
import kotlinx.serialization.json.Json
import org.apache.commons.compress.archivers.zip.ZipArchiveEntry
import org.apache.commons.compress.archivers.zip.ZipArchiveOutputStream
import java.io.ByteArrayInputStream
import java.io.ByteArrayOutputStream
import java.io.InputStream
import jakarta.inject.Singleton

interface ExportService {
    fun exportAsJson(userId: Int): String
    fun exportAsZip(userId: Int): InputStream
}

@Singleton
internal class ExportServiceImpl(
    private val noteRepository: NoteRepository,
    private val json: Json,
) : ExportService {

    override fun exportAsJson(userId: Int): String {
        val notes = noteRepository.export(userId)
        return json.encodeToString(ListSerializer(ExportedNote.serializer()), notes)
    }

    private fun sanitizeFilename(inputName: String): String = inputName.replace("[^a-zA-Z0-9-_.]".toRegex(), "_")

    override fun exportAsZip(userId: Int): InputStream {
        val notes = noteRepository.export(userId)
        val zipOutput = ZipOutput()
        zipOutput.use { zip ->
            notes.forEach {
                val name = sanitizeFilename(it.title)
                zip.write("notes/$name.md", it.markdown)
            }
        }
        return ByteArrayInputStream(zipOutput.outputStream.toByteArray())
    }
}

private class ZipOutput : AutoCloseable {
    val outputStream = ByteArrayOutputStream()
    private val zipOutputStream = ZipArchiveOutputStream(outputStream)

    fun write(path: String, content: String) {
        val entry = ZipArchiveEntry(path)
        zipOutputStream.putArchiveEntry(entry)
        zipOutputStream.write(content.toByteArray())
        zipOutputStream.closeArchiveEntry()
    }

    override fun close() {
        zipOutputStream.finish()
        zipOutputStream.close()
    }
}