package com.github.javaparser.utils;

import java.io.File;
import java.net.URISyntaxException;
import java.nio.file.Path;
import java.nio.file.Paths;

import static com.github.javaparser.utils.Utils.capitalize;
import static com.github.javaparser.utils.Utils.decapitalize;

public final class CodeGenerationUtils {
    private CodeGenerationUtils() {
    }

    public static String getterName(Class<?> type, String name) {
        if (name.startsWith("is")) {
            return name;
        } else if (type.equals(Boolean.class)) {
            return "is" + capitalize(name);
        }
        return "get" + capitalize(name);
    }

    public static String getterToPropertyName(String getterName) {
        if (getterName.startsWith("is")) {
            return decapitalize(getterName.substring("is".length()));
        } else if (getterName.startsWith("get")) {
            return decapitalize(getterName.substring("get".length()));
        } else if (getterName.startsWith("has")) {
            return decapitalize(getterName.substring("has".length()));
        }
        throw new IllegalArgumentException("Unexpected getterName '" + getterName + "'");
    }

    public static String setterName(String fieldName) {
        if (fieldName.startsWith("is")) {
            return "set" + fieldName.substring(2);
        }
        return "set" + capitalize(fieldName);
    }

    public static String optionalOf(String text, boolean isOptional) {
        if (isOptional) {
            return f("Optional.of(%s)", text);
        } else {
            return "Optional.empty()";
        }
    }

    /**
     * A shortcut to String.format.
     */
    public static String f(String format, Object... params) {
        return String.format(format, params);
    }

    /**
     * Calculates the path to a file in a package.
     *
     * @param root the root directory in which the package resides
     * @param pkg the package in which the file resides, like "com.laamella.parser"
     * @param file the filename of the file in the package.
     */
    public static Path fileInPackageAbsolutePath(String root, String pkg, String file) {
        pkg = packageToPath(pkg);
        return Paths.get(root, pkg, file).normalize();
    }

    public static Path fileInPackageAbsolutePath(Path root, String pkg, String file) {
        return fileInPackageAbsolutePath(root.toString(), pkg, file);
    }

    /**
     * Turns a package and a file into a relative path. "com.laamella" and "Simple.java" will become
     * "com/laamella/Simple.java"
     */
    public static Path fileInPackageRelativePath(String pkg, String file) {
        pkg = packageToPath(pkg);
        return Paths.get(pkg, file).normalize();
    }

    /**
     * Converts a package name like "com.laamella.parser" to a path like "com/laamella/parser"
     */
    public static String packageToPath(String pkg) {
        return pkg.replace(".", File.separator);
    }

    /**
     * Calculates the path of a package.
     *
     * @param root the root directory in which the package resides
     * @param pkg the package, like "com.laamella.parser"
     */
    public static Path packageAbsolutePath(String root, String pkg) {
        pkg = packageToPath(pkg);
        return Paths.get(root, pkg).normalize();
    }

    public static Path packageAbsolutePath(Path root, String pkg) {
        return packageAbsolutePath(root.toString(), pkg);
    }

    /**
     * @return the root directory of the classloader for class c.
     */
    public static Path classLoaderRoot(Class<?> c) {
        try {
            return Paths.get(c.getProtectionDomain().getCodeSource().getLocation().toURI());
        } catch (URISyntaxException e) {
            throw new AssertionError("Bug in JavaParser, please report.", e);
        }
    }

    /**
     * Useful for locating source code in your Maven project. Finds the classpath for class c, then backs up out of
     * "target/(test-)classes", giving the directory containing the pom.xml.
     */
    public static Path mavenModuleRoot(Class<?> c) {
        return classLoaderRoot(c).resolve(Paths.get("..", "..")).normalize();
    }

    /**
     * Shortens path "full" by cutting "difference" off the end of it.
     */
    public static Path subtractPaths(Path full, Path difference) {
        while (difference != null) {
            if (difference.getFileName().equals(full.getFileName())) {
                difference = difference.getParent();
                full = full.getParent();
            } else {
                throw new RuntimeException(f("'%s' could not be subtracted from '%s'", difference, full));
            }
        }
        return full;
    }
}