package dslog;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;
import java.util.function.Supplier;

class Logdir {
	public static class LogSet {
		public final String name;
		public LogSet(String name) {
			this.name = name;
		}
		public Path dslogPath, dseventsPath, pdplogPath;

		public String toString() {
			return name+" "+verstr(this::dslog)+"/"+verstr(this::dsevents)+"/"+verstr(this::pdplog);
		}

		private static String verstr(Versioned.Supplier getter) {
			try (Versioned thing = getter.get()) {
				if (thing == null) {
					return "␕";
				}
				return ""+thing.version();
			} catch (IOException e) {
				return "☠";
			}
		}

		public DslogReader dslog() throws IOException {
			if (dslogPath == null) {
				return null;
			}
			return new DslogReader(Files.newInputStream(dslogPath));
		}
		public DseventsReader dsevents() throws IOException {
			if (dseventsPath == null) {
				return null;
			}
			return new DseventsReader(Files.newInputStream(dseventsPath));
		}
		public PdplogReader pdplog() throws IOException {
			if (pdplogPath == null) {
				return null;
			}
			return new PdplogReader(Files.newInputStream(pdplogPath));
		}
	}

	private static LogSet getSet(Map<String, LogSet> sets, String filename) {
		String setname = filename.substring(0, filename.lastIndexOf('.'));
		LogSet set;
		set = sets.get(setname);
		if (set == null) {
			set = new LogSet(setname);
			sets.put(set.name, set);
		}
		return set;
	}
	public static SortedMap<String, LogSet> opendir(String dirname) throws IOException {
		SortedMap<String, LogSet> logsets = new TreeMap<String, LogSet>();
		List<Exception> errs = new ArrayList<Exception>();
		Files.list(Paths.get(dirname)).forEach(filepath->{
			String filename = filepath.getFileName().toString();
			if (filename.endsWith(".dslog")) {
				getSet(logsets, filename).dslogPath = filepath;
			} else if (filename.endsWith(".dsevents")) {
				getSet(logsets, filename).dseventsPath = filepath;
			} else if (filename.endsWith(".pdplog")) {
				getSet(logsets, filename).pdplogPath = filepath;
			}
		});
		return logsets;
	}
}