package Torello.Java.Build;

import Torello.Java.StringParse;
import Torello.Java.FileNode;
import Torello.Java.RTC;

import Torello.Java.Additional.Counter;

import java.io.File;
import java.io.FilenameFilter;
import java.io.IOException;

import java.util.ArrayList;
import java.util.function.Predicate;

import Torello.Java.ReadOnly.ROArrayListBuilder;
import Torello.Java.ReadOnly.ROHashtableBuilder;
import Torello.Java.ReadOnly.ReadOnlyList;
import Torello.Java.ReadOnly.ReadOnlyArrayList;

import Torello.Java.StrCSV;

import static Torello.Java.C.BRED;
import static Torello.Java.C.RESET;

/**
 * Given a list of packges, collate a list of files to processed by the various
 * Build-Stages.
 */
@Torello.JavaDoc.StaticFunctional
public class Files
{
    // Completely irrelevant, and the 'private' modifier keeps it off of JavaDoc
    private Files() { }

    private static final String FS = File.separator;


    // ********************************************************************************************
    // ********************************************************************************************
    // File-Array Builder
    // ********************************************************************************************
    // ********************************************************************************************


    private static final int addMore
        (ROArrayListBuilder<String> b, String dir, boolean depth, FilenameFilter filter)
    {
        Counter c = new Counter(0);

        FileNode
            .createRoot         (dir)
            .loadTree           (depth ? -1 : 0, filter, null)
            .flattenJustFiles   (RTC.FULLPATH_VECTOR())
            .forEach            ((String srcFileName) -> { c.addOne(); b.add(srcFileName); });

        return c.get();
    }


    // ********************************************************************************************
    // ********************************************************************************************
    // Stage 01, Compile Files
    // ********************************************************************************************
    // ********************************************************************************************


    /**
     * Retrieve the Stage 1 Files List of {@code '.java'} Files.  The master list that is returned
     * as a result of this method is the complete list of files sent to {@code 'javac'}, as command
     * line parameters.
     * 
     * @param packagesToCompile The list of packages whose files need to be compiled.  This list,
     * itself, was built by class {@link Packages} method
     * {@link Packages#packagesToCompile(Builder) builder} using all User-Provided Configurations,
     * and Command-Line Switch Choices.
     * 
     * @param logAndScreen Prints log information to both the log and the terminal-screen.
     * 
     * @return The list of files to be compiled by the Stage 1 Build-Class
     * {@link S01_JavaCompiler}.
     * 
     * @throws IOException Required due to the {@code Appendable} parameter {@code 'logAndScreen'}
     * @see Printing#printFilesCount(ReadOnlyList, ArrayList, Appendable)
     * @see BuildPackage#pkgRootDirectory
     * @see BuildPackage#hasSubPackages
     * @see BuildPackage#hasUpgradeFilesDir
     * @see BuildPackage#hasPackageSourceDir
     * @see BuildPackage#helperPackages
     */
    public static ReadOnlyList<String> filesToCompile(
            ReadOnlyList<BuildPackage>  packagesToCompile,
            Appendable                  logAndScreen
        )
        throws IOException
    {
        // This is much easier to understand.  It is actually smarter to just go to the class
        // "Files" and look what it is doing.  The loop that collects the files for a "Package"
        // uses the following BuildPackage boolean-fields, which are defined, as below, inside the
        // BuildPackage-Constructor:
        //
        // BuildPackage.hasSubPackages     = (flags & HAS_SUB_PACKAGES)    >= 1;
        // BuildPackage.pkgRootDirectory   = classPathLocation + fullName.replace(".", FS) + FS;
        //
        // this.helperPackages = (helperPackages == null) || (helperPackages.length == 0)
        //     ? EMPTY_LIST
        //     : ReadOnlyList.of(helperPackages);
        //
        // Just go to class "Files" to see how those "BuildPackage" boolean Configuration-Fields
        // pick files to insert into the "filesToCompile" list.

        // This keeps a complete list of all files that will need to be compiled
        ROArrayListBuilder<String> b = new ROArrayListBuilder<>();

        // This is used for printing to the screen only, it is discarded when this method
        // exits.

        final ArrayList<Integer> packageFilesCount = new ArrayList<>(packagesToCompile.size());

        for (final BuildPackage pkg : packagesToCompile)
        {
            int count = 0;

            count += addMore(b, pkg.pkgRootDirectory, pkg.hasSubPackages, FileNode.JAVA_FILES);

            if (pkg.hasUpgradeFilesDir) count += addMore
                (b, pkg.pkgRootDirectory + "upgrade-files" + FS, true, FileNode.JAVA_FILES);

            if (pkg.hasPackageSourceDir) count += addMore
                (b, pkg.pkgRootDirectory + "package-source" + FS, true, FileNode.JAVA_FILES);

            for (String helperPkgDirName : pkg.helperPackages) count += addMore
                (b, helperPkgDirName, false, FileNode.JAVA_FILES);

            packageFilesCount.add(Integer.valueOf(count));
        }

        Printing.printFilesCount(packagesToCompile, packageFilesCount, logAndScreen);

        return b.build();
    }


    // ********************************************************************************************
    // ********************************************************************************************
    // Stage 02, JavaDoc Files
    // ********************************************************************************************
    // ********************************************************************************************


    /**
     * Retrieve the Stage 1 Files List of {@code '.java'} Files.  The master list that is returned
     * as a result of this method is the complete list of files sent to {@code 'javadoc'}, as
     * command line parameters.
     * 
     * @param packagesToJavaDoc The list of packages whose files need to be compiled.  This list,
     * itself, was built by class {@link Packages} method
     * {@link Packages#packagesToCompile(Builder) builder} using all User-Provided Configurations,
     * and Command-Line Switch Choices.
     * 
     * @param logAndScreen Prints log information to both the log and the terminal-screen.
     * 
     * @return The list of files to be compiled by the Stage 2 Build-Class
     * {@link S02_JavaDoc}.
     * 
     * @throws IOException Required due to the {@code Appendable} parameter {@code 'logAndScreen'}
     * @see Printing#printFilesCount(ReadOnlyList, ArrayList, Appendable)
     * @see BuildPackage#pkgRootDirectory
     * @see BuildPackage#hasPackageSourceDir
     */
    public static ReadOnlyList<String> filesToJavaDoc(
            ReadOnlyList<BuildPackage>  packagesToJavaDoc,
            Appendable                  logAndScreen
        )
        throws IOException
    {
        // This keeps a complete list of all files that will need to be compiled
        ROArrayListBuilder<String> b = new ROArrayListBuilder<>();

        // This is used for printing to the screen only, it is discarded when this method
        // exits.

        final ArrayList<Integer> packageFilesCount = new ArrayList<>(packagesToJavaDoc.size());

        for (final BuildPackage pkg : packagesToJavaDoc)
        {
            int count = 0;

            count += addMore(b, pkg.pkgRootDirectory, false, FileNode.JAVA_FILES);

            if (pkg.hasPackageSourceDir) count += addMore
                (b, pkg.pkgRootDirectory + "package-source" + FS, true, FileNode.JAVA_FILES);

            packageFilesCount.add(Integer.valueOf(count));
        }

        Printing.printFilesCount(packagesToJavaDoc, packageFilesCount, logAndScreen);

        return b.build();
    }
}