vashilK/Redis-cache

package org.nki.redis.cache.generator;


import org.nki.redis.cache.exceptions.IoException;
import org.nki.redis.cache.exceptions.ValidationException;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Writer;
import java.net.URL;
import java.net.URLDecoder;
import java.nio.charset.StandardCharsets;
import java.util.HashMap;
import java.util.Map;
import java.util.Objects;

/**
 * Author Neeschal Kissoon created on 17/12/2022
 */
public final class GeneratorEngine {

    private GeneratorEngine() {
    }

    public static GeneratorEngine init() {
        return new GeneratorEngine();
    }

    public void create(String template, GeneratorContext generatorContext,
                       String fileName, String extension) {
        try {
            HashMap<String, String> parameters = 
                    generatorContext.getParameters();
            if (parameters.isEmpty()) {
                throw new ValidationException("Parameters are required!");
            }

            validateParameters(parameters);
            for (Map.Entry<String, String> entry : parameters.entrySet()) {
                String target = entry.getKey();
                String replacement = entry.getValue();
                template = template.replace(target, replacement);
            }

            String packageRoot = Objects.nonNull(parameters.get("packageName")) 
                    ? parameters.get("packageName").replace(".", "/") + "/" 
                    : "";
            generateDirectories(packageRoot);
            Writer writer = new FileWriter(new File(
                    getProjectPath() + "/target/generated-sources/main/java/" 
                            + packageRoot +
                            fileName + "TypeReference." + extension));
            writer.append(template);
            writer.flush();
            writer.close();
        } catch (IOException e) {
            throw new IoException(e.getCause());
        }
    }

    private static void generateDirectories(String packageRoot) {
        File theDir =
                new File(getProjectPath() +
                        "/target/generated-sources/main/java/" +
                        packageRoot);
        if (!theDir.exists()) {
            boolean isPerformed = theDir.mkdirs();
        }
    }

    private static String getProjectPath() {
        String path = Objects.requireNonNull(getResource()).getPath();
        String fullPath = URLDecoder.decode(path, StandardCharsets.UTF_8);
        String[] absolutePath = fullPath.split("target");
        return absolutePath[0];
    }

    private static URL getResource() {
        return ModelGenerator.class.getClassLoader().getResource("");
    }

    private static boolean validateParameters(HashMap<String, String> parameters) {
        try {
            parameters.get("packageName");
        } catch (Exception e) {
            throw new ValidationException("Required packageName missing.");
        }

        return true;
    }
}