BaseDirGenerator.java

package com.wingsofts.mvphelper.biz.dir.generator.impl;

import com.intellij.openapi.actionSystem.AnActionEvent;
import com.intellij.openapi.actionSystem.CommonDataKeys;
import com.intellij.openapi.actionSystem.PlatformDataKeys;
import com.intellij.openapi.command.WriteCommandAction;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.ui.Messages;
import com.intellij.psi.PsiDirectory;
import com.intellij.psi.PsiJavaFile;
import com.wingsofts.mvphelper.biz.dir.generator.DirGenerator;
import org.jetbrains.annotations.NotNull;

import java.util.ResourceBundle;

import static com.wingsofts.mvphelper.biz.EventLogger.log;

/**
 * @author DengChao
 * @see #moveDirPointer(PsiDirectory, String)
 * @see #generateDirsBasedOnSuffix(String)
 * @see #onGenerateForkDirs(String)
 * @since 2017/4/24.
 */
@SuppressWarnings({"ConstantConditions", "WeakerAccess"})
abstract class BaseDirGenerator implements DirGenerator {
    protected final Project myProject;
    protected final String myPackageName;//where the action happens
    protected PsiDirectory myCurrentDir;//the base line of dir generation
    protected PsiDirectory myContractDir;
    protected PsiDirectory myModelDir;
    protected PsiDirectory myPresenterDir;
    protected String myPrefix;

    BaseDirGenerator(@NotNull AnActionEvent actionEvent, @NotNull String prefix) {
        this.myPrefix = prefix;
        myProject = actionEvent.getData(PlatformDataKeys.EDITOR).getProject();

        PsiJavaFile javaFile = (PsiJavaFile) actionEvent.getData(CommonDataKeys.PSI_FILE);
        myPackageName = javaFile.getPackageName();
        locateRootDir(javaFile.getContainingFile().getParent());
    }

    /**
     * Locate the root dir of current project.<br/>
     * For Android studio project, 'java' folder is always the root of any model by default.<br/>
     * For IDEA java project, 'src' folder is always the root of any model by default.
     *
     * @param currentDir where the action happens
     */
    private void locateRootDir(PsiDirectory currentDir) {
        String currentDirName = currentDir.getName();
        if (currentDirName.equals("java")
                || currentDirName.equals("src")) {
            myCurrentDir = currentDir;
        } else {
            PsiDirectory parent = currentDir.getParent();
            if (parent != null) {
                locateRootDir(parent);//if this folder is not the root, then try its parent.
            } else {
                //when there is no more parent, we reached the ROOT of a hard-disk...
                //if we still can't locate myCurrentDir by now...
                //I guess..not the plugin's fault.. =(
                Messages.showErrorDialog(
                        "I can't imagine what happens to your project," +
                                " technically, no project could reach here.\n" +
                                " For your project match the IDEA's 'Java Project' definition," +
                                " and it match our basic rule: 'Contract' under contract-package and 'Presenter' under presenter-package." +
                                " Since it does happened, report us the detail please:" +
                                " image of this dialog, image of your project structure tree, and your description\n" +
                                ResourceBundle.getBundle("string").getString("feedBackUrl"),
                        "Locate Root Dir Error");
                throw new RuntimeException("The plugin cannot find a root dir like \"java\" or \"src\"");
            }
        }
    }

    /**
     * <i><b>Make sure to call this on sub-class#{@link #start()}'s first line</b></i>
     *
     * @param suffix the suffix of the package witch used to determine where should have a fork.
     */
    protected void generateDirsBasedOnSuffix(@NotNull String suffix) {
        boolean isForkDirGenerated = false;
        String[] subPackages = myPackageName.split("\\.");
        for (String subPackage : subPackages) {
            if (!subPackage.endsWith(suffix)) {//if the package does not end with 'contract':
                if (isForkDirGenerated) {// and the 'presenter' and 'model' dir already generated,
                    myContractDir = moveDirPointer(myContractDir, subPackage);
                    myModelDir = moveDirPointer(myModelDir, subPackage);
                    myPresenterDir = moveDirPointer(myPresenterDir, subPackage);
                }// but the 'presenter' and 'model' dir has not been generated,
            } else {
                onGenerateForkDirs(subPackage);
                isForkDirGenerated = true;//update the flag
            }
            //the current dir is the base line, so
            //no matter what happens, move myCurrentDir pointer to it's child;
            myCurrentDir = moveDirPointer(myCurrentDir, subPackage);
        }
    }

    /**
     * Move the pointer to it's sub-package.<br/>
     * sub-package will be generate if it's not exist.
     *
     * @param subPackage the sub-package's name
     */
    @NotNull
    protected PsiDirectory moveDirPointer(@NotNull final PsiDirectory currentDir, @NotNull final String subPackage) {
        final PsiDirectory[] subDirectory = {currentDir.findSubdirectory(subPackage)};
        if (subDirectory[0] == null) {
            WriteCommandAction.runWriteCommandAction(currentDir.getProject(), () -> {
                subDirectory[0] = currentDir.createSubdirectory(subPackage);
                log("BaseDirGenerator: " + currentDir.getVirtualFile().getPath() + "/" + subPackage + " generated");
            });
        }
        return subDirectory[0];
    }

    /**
     * Here the fork appears, sub-class have to implement this method to achieve particular work.<br/>
     * For example: subPackage = "Acontract"<br/>
     * Then this method should
     * <ol>
     * <li>Move {@link #myContractDir} to {@link #myCurrentDir}.subPackage</li>
     * <li>Move {@link #myModelDir} to "Amodel"</li>
     * <li>Move {@link #myPresenterDir} to "Apresenter"</li>
     * </ol>
     *
     * @param subPackage the name of the dir which should have siblings
     * @see #moveDirPointer(PsiDirectory, String)
     */
    protected abstract void onGenerateForkDirs(@NotNull String subPackage);

}