SquirrelJME/SquirrelJME

// -*- Mode: Java; indent-tabs-mode: t; tab-width: 4 -*-
// ---------------------------------------------------------------------------
// Multi-Phasic Applications: SquirrelJME
//     Copyright (C) Stephanie Gawroriski <xer@multiphasicapps.net>
// ---------------------------------------------------------------------------
// SquirrelJME is under the Mozilla Public License Version 2.0.
// See license.mkd for licensing and copyright information.
// ---------------------------------------------------------------------------

package cc.squirreljme.debugger;

import cc.squirreljme.runtime.cldc.full.SystemPath;
import cc.squirreljme.runtime.cldc.full.SystemPathProvider;
import com.oracle.json.JsonArrayBuilder;
import com.oracle.json.JsonObject;
import com.oracle.json.JsonReader;
import com.oracle.json.JsonValue;
import com.oracle.json.JsonWriter;
import com.oracle.json.spi.JsonProvider;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;
import java.nio.file.StandardOpenOption;
import java.util.ArrayList;
import java.util.List;

/**
 * Manager for preferences.
 *
 * @since 2024/01/28
 */
public class PreferencesManager
{
    /** The path where the configuration is. */
    protected final Path configPath;
    
    /**
     * Initializes the preference manager.
     *
     * @since 2024/01/28
     */
    public PreferencesManager()
    {
        this.configPath = SystemPathProvider.provider()
            .ofFallback(SystemPath.CONFIG).resolve("debugger.json");
    }
    
    /**
     * Loads the given preferences.
     *
     * @param __prefs The preferences to load.
     * @throws NullPointerException On null arguments.
     * @since 2024/01/28
     */
    public void load(Preferences __prefs)
        throws NullPointerException
    {
        if (__prefs == null)
            throw new NullPointerException("NARG");
        
        // Load in the JSON data
        JsonProvider provider = JsonProvider.provider();
        try (InputStream in = Files.newInputStream(this.configPath,
            StandardOpenOption.READ);
             JsonReader reader = provider.createReader(in))
        {
            // Read in JSON structure
            JsonObject struct = reader.readObject();
            
            // Boolean values
            __prefs.setResumeOnConnect(struct.getBoolean(
                "resumeOnConnect",
                Preferences.DEFAULT_RESUME_ON_CONNECT));
            __prefs.setLocalClassOnly(struct.getBoolean(
                "localClassOnly",
                Preferences.DEFAULT_LOCAL_CLASS_ONLY));
            
            // String values
            __prefs.setLastAddress(struct.getString(
                "lastAddress",
                Preferences.DEFAULT_LAST_ADDRESS));
            
            // Parse in all paths
            List<Path> paths = new ArrayList<>();
            for (JsonValue value : struct.getJsonArray("classSearchPath"))
                paths.add(Paths.get(value.toString()));
            __prefs.getClassSearchPath().clear();
            __prefs.getClassSearchPath().addAll(paths);
        }
        catch (IOException __e)
        {
            __e.printStackTrace();
        }
    }
    
    /**
     * Stores the given preferences.
     *
     * @param __prefs The preferences to store.
     * @throws IOException On write errors.
     * @throws NullPointerException On null arguments.
     * @since 2024/01/28
     */
    public void store(Preferences __prefs)
        throws IOException, NullPointerException
    {
        if (__prefs == null)
            throw new NullPointerException("NARG");
        
        // Write to disk
        Path tempFile = null;
        JsonProvider provider = JsonProvider.provider();
        try
        {
            // Write everything into a temporary file first
            tempFile = Files.createTempFile("debugger", ".json");
            try (OutputStream out = Files.newOutputStream(tempFile,
                StandardOpenOption.WRITE, StandardOpenOption.CREATE,
                StandardOpenOption.TRUNCATE_EXISTING);
                JsonWriter writer = provider.createWriter(out))
            {
                // Search path where everything is
                JsonArrayBuilder searchPath = provider.createArrayBuilder();
                for (Path path : __prefs.getClassSearchPath())
                    searchPath.add(path.toAbsolutePath().toString());
                
                // Build base object
                JsonObject object = provider.createObjectBuilder()
                    .add("resumeOnConnect", __prefs.isResumeOnConnect())
                    .add("localClassOnly", __prefs.isLocalClassOnly())
                    .add("lastAddress", __prefs.getLastAddress())
                    .add("classSearchPath", searchPath)
                    .build();
                
                // Write it out
                writer.writeObject(object);
            }
            
            // Make sure the configuration directory actually exists
            Path configPath = this.configPath;
            Files.createDirectories(configPath.getParent());
            
            // Then move over the configuration
            Files.move(tempFile, configPath,
                StandardCopyOption.REPLACE_EXISTING);
        }
        
        // Cleanup temp file if it exists
        finally
        {
            if (tempFile != null)
                try
                {
                    Files.delete(tempFile);
                }
                catch (IOException __ignored)
                {
                    // Ignored
                }
        }
    }
}