package im.rosetta.api;

import im.rosetta.storage.FileStore;
import jakarta.ws.rs.Consumes;
import jakarta.ws.rs.GET;
import jakarta.ws.rs.POST;
import jakarta.ws.rs.Path;
import jakarta.ws.rs.PathParam;
import jakarta.ws.rs.Produces;
import jakarta.ws.rs.core.MediaType;
import jakarta.ws.rs.core.Response;
import jakarta.ws.rs.core.StreamingOutput;
import org.glassfish.jersey.media.multipart.FormDataParam;

import java.io.IOException;
import java.io.InputStream;
import java.nio.file.Files;
import java.util.Map;
import java.util.Optional;
import java.util.UUID;

@Path("/")
public class CdnResource {
    private final FileStore fileStore;

    public CdnResource(FileStore fileStore) {
        this.fileStore = fileStore;
    }

    @POST
    @Path("u")
    @Consumes(MediaType.MULTIPART_FORM_DATA)
    @Produces(MediaType.APPLICATION_JSON)
    public Response upload(@FormDataParam("file") InputStream inputStream) {
        if (inputStream == null) {
            return Response.status(Response.Status.BAD_REQUEST)
                    .entity(Map.of("error", "file is required"))
                    .build();
        }
        try {
            String tag = fileStore.save(inputStream);
            return Response.ok(Map.of("t", tag)).build();
        } catch (IOException e) {
            return Response.serverError()
                    .entity(Map.of("error", "upload failed"))
                    .build();
        }
    }

    @GET
    @Path("d/{tag}")
    @Produces(MediaType.APPLICATION_OCTET_STREAM)
    public Response download(@PathParam("tag") String tag) {
        if (!isValidTag(tag)) {
            return Response.status(Response.Status.BAD_REQUEST)
                    .entity(Map.of("error", "invalid tag"))
                    .build();
        }
        try {
            Optional<java.nio.file.Path> file = fileStore.getIfValid(tag);
            if (file.isEmpty()) {
                return Response.status(Response.Status.NOT_FOUND)
                        .entity(Map.of("error", "not found"))
                        .build();
            }
            StreamingOutput stream = output -> Files.copy(file.get(), output);
            return Response.ok(stream)
                    .header("Content-Disposition", "attachment; filename=\"" + tag + "\"")
                    .build();
        } catch (IOException e) {
            return Response.serverError()
                    .entity(Map.of("error", "download failed"))
                    .build();
        }
    }

    private boolean isValidTag(String tag) {
        try {
            UUID.fromString(tag);
            return true;
        } catch (IllegalArgumentException ex) {
            return false;
        }
    }
}