#include <QCoreApplication>
#include <QTextStream>
#include <QFile>
#include <QDir>
#include <QFileInfo>

#include "coalesced.h"

static QTextStream cout(stdout);
static QTextStream cerr(stderr);

void printError(const QString& message)
{
    cerr << "Error: " << message << "\n";
    cerr.flush();
}

void showUsage()
{
    cout << QString("UDK Config/Localization Manipulator %1\n").arg(QCoreApplication::applicationVersion());
    cout << "Extract and pack UDK/UE3 coalesced Config/Localization files\n\n";
    cout << "Usage:\n";
    cout << QString("  %1 <command> [arguments]\n\n").arg(QCoreApplication::applicationName());
    cout << "Commands:\n";
    cout << "  list <file>                                  List files in archive\n";
    cout << "  info <file>                                  Show archive metadata\n";
    cout << "  unpack <file> [output_dir]                   Extract all INI files\n";
    cout << "  pack <input_dir> <output_file>               Pack directory into coalesced file\n";
    cout << "  extract <file> <index|name> [output]         Extract single file\n\n";
    cout << "Options:\n";
    cout << "  -h, --help                                   Show this help message\n";
    cout << "  -v, --version                                Show version\n\n";
    cout << "Drag & Drop:\n";
    cout << "  Drag a coalesced file onto exe               Extracts to ./<name>_<ext>/\n";
    cout << "  Drag a folder onto exe                       Packs to ./<name>.<ext>\n";
    cout << "  (folder coalesced_ini -> coalesced.ini)\n";
    cout.flush();
}

int cmdList(const QStringList& args)
{
    if (args.isEmpty()) {
        printError(QString("Usage: %1 list <file>").arg(QCoreApplication::applicationName()));
        return 1;
    }

    CoalescedFile coalesced;
    if (!coalesced.load(args[0])) {
        printError(coalesced.lastError());
        return 1;
    }

    cout << QString("%1  %2  %3\n")
            .arg("Index", 5)
            .arg("Size", 8)
            .arg("Filename");
    cout << QString("%1  %2  %3\n")
            .arg(QString("-").repeated(5), 5)
            .arg(QString("-").repeated(8), 8)
            .arg(QString("-").repeated(50));

    const QList<IniEntry>& entries = coalesced.entries();
    for (int i = 0; i < entries.count(); ++i) {
        const IniEntry& entry = entries[i];
        cout << QString("%1  %2  %3\n")
                .arg(i, 5)
                .arg(entry.content.size(), 8)
                .arg(entry.filename);
    }

    cout << QString("\nTotal: %1 files, %2 bytes\n")
            .arg(coalesced.count())
            .arg(coalesced.totalSize());
    cout.flush();
    return 0;
}

int cmdInfo(const QStringList& args)
{
    if (args.isEmpty()) {
        printError(QString("Usage: %1 info <file>").arg(QCoreApplication::applicationName()));
        return 1;
    }

    CoalescedFile coalesced;
    if (!coalesced.load(args[0])) {
        printError(coalesced.lastError());
        return 1;
    }

    cout << "Archive Information:\n";
    cout << QString("  File: %1\n").arg(coalesced.loadedPath());
    cout << QString("  Entries: %1\n").arg(coalesced.count());
    cout << QString("  Total content size: %1 bytes\n").arg(coalesced.totalSize());

    qint64 minSize = LLONG_MAX;
    qint64 maxSize = 0;
    QString minFile, maxFile;

    for (const IniEntry& entry : coalesced.entries()) {
        if (entry.content.size() < minSize) {
            minSize = entry.content.size();
            minFile = entry.filename;
        }
        if (entry.content.size() > maxSize) {
            maxSize = entry.content.size();
            maxFile = entry.filename;
        }
    }

    if (coalesced.count() > 0) {
        cout << QString("  Smallest: %1 bytes (%2)\n").arg(minSize).arg(minFile);
        cout << QString("  Largest: %1 bytes (%2)\n").arg(maxSize).arg(maxFile);
        cout << QString("  Average: %1 bytes\n").arg(coalesced.totalSize() / coalesced.count());
    }

    cout.flush();
    return 0;
}

int cmdUnpack(const QStringList& args)
{
    if (args.isEmpty()) {
        printError(QString("Usage: %1 unpack <file> [output_dir]").arg(QCoreApplication::applicationName()));
        return 1;
    }

    CoalescedFile coalesced;
    if (!coalesced.load(args[0])) {
        printError(coalesced.lastError());
        return 1;
    }

    QString outputDir;
    if (args.size() > 1) {
        outputDir = args[1];
    } else {
        // Default: use filename with _ instead of . (e.g., coalesced.ini -> coalesced_ini)
        QFileInfo fi(args[0]);
        outputDir = fi.completeBaseName() + "_" + fi.suffix();
    }

    QDir dir(outputDir);
    if (!dir.exists() && !dir.mkpath(".")) {
        printError(QString("Cannot create output directory: %1").arg(outputDir));
        return 1;
    }

    int extracted = 0;
    qint64 totalBytes = 0;

    for (const IniEntry& entry : coalesced.entries()) {
        QString localPath = entry.filename;

        // Remove leading ".." components for safety
        while (localPath.startsWith("..\\") || localPath.startsWith("../")) {
            localPath = localPath.mid(3);
        }
        localPath.replace('\\', '/');

        QString fullPath = dir.filePath(localPath);

        QFileInfo fi(fullPath);
        if (!fi.dir().exists() && !QDir().mkpath(fi.path())) {
            printError(QString("Cannot create directory: %1").arg(fi.path()));
            continue;
        }

        QFile file(fullPath);
        if (!file.open(QIODevice::WriteOnly)) {
            printError(QString("Cannot write file: %1").arg(fullPath));
            continue;
        }

        file.write(entry.content);
        file.close();

        extracted++;
        totalBytes += entry.content.size();
    }

    cout << QString("Extracted %1 files (%2 bytes) to %3\n")
            .arg(extracted)
            .arg(totalBytes)
            .arg(QDir(outputDir).absolutePath());
    cout.flush();
    return 0;
}

int cmdPack(const QStringList& args)
{
    if (args.size() < 2) {
        printError(QString("Usage: %1 pack <input_dir> <output_file>").arg(QCoreApplication::applicationName()));
        return 1;
    }

    CoalescedFile packer;
    if (!packer.packDirectory(args[0])) {
        printError(packer.lastError());
        return 1;
    }

    if (!packer.save(args[1])) {
        printError(QString("Cannot write output file: %1").arg(args[1]));
        return 1;
    }

    cout << QString("Packed %1 files (%2 bytes) to %3\n")
            .arg(packer.count())
            .arg(packer.totalSize())
            .arg(args[1]);
    cout.flush();
    return 0;
}

int cmdExtract(const QStringList& args)
{
    if (args.size() < 2) {
        printError(QString("Usage: %1 extract <file> <index|name> [output]").arg(QCoreApplication::applicationName()));
        return 1;
    }

    CoalescedFile coalesced;
    if (!coalesced.load(args[0])) {
        printError(coalesced.lastError());
        return 1;
    }

    QString target = args[1];
    const IniEntry* entry = nullptr;

    bool ok;
    int index = target.toInt(&ok);
    if (ok) {
        entry = coalesced.entry(index);
        if (!entry) {
            printError(QString("Index %1 out of range (0-%2)").arg(index).arg(coalesced.count() - 1));
            return 1;
        }
    } else {
        entry = coalesced.entry(target);
        if (!entry) {
            printError(QString("File not found: %1").arg(target));
            return 1;
        }
    }

    QString outputPath;
    if (args.size() > 2) {
        outputPath = args[2];
    } else {
        QFileInfo fi(entry->filename);
        outputPath = fi.fileName();
    }

    QFile file(outputPath);
    if (!file.open(QIODevice::WriteOnly)) {
        printError(QString("Cannot write file: %1").arg(outputPath));
        return 1;
    }

    file.write(entry->content);
    file.close();

    cout << QString("Extracted '%1' to '%2' (%3 bytes)\n")
            .arg(entry->filename)
            .arg(outputPath)
            .arg(entry->content.size());
    cout.flush();
    return 0;
}

int main(int argc, char *argv[])
{
    QCoreApplication app(argc, argv);
    QCoreApplication::setApplicationName("udk-manip");
    QCoreApplication::setApplicationVersion("1.2");

    QStringList args = app.arguments();
    args.removeFirst(); // Remove program name

    if (args.isEmpty()) {
        showUsage();
        return 1;
    }

    QString cmd = args.takeFirst().toLower();

    if (cmd == "-h" || cmd == "--help" || cmd == "help") {
        showUsage();
        return 0;
    }

    if (cmd == "-v" || cmd == "--version" || cmd == "version") {
        cout << QString("%1 %2\n").arg(QCoreApplication::applicationVersion()).arg(QCoreApplication::applicationName());
        cout.flush();
        return 0;
    }

    if (cmd == "list") {
        return cmdList(args);
    } else if (cmd == "info") {
        return cmdInfo(args);
    } else if (cmd == "unpack") {
        return cmdUnpack(args);
    } else if (cmd == "pack") {
        return cmdPack(args);
    } else if (cmd == "extract") {
        return cmdExtract(args);
    } else if (QFileInfo(cmd).isDir()) {
        // Directory dragged onto exe - derive output filename from folder name
        // Folder "coalesced_ini" -> output "coalesced.ini"
        CoalescedFile packer;
        if (!packer.packDirectory(cmd)) {
            printError(packer.lastError());
            return 1;
        }
        // Get folder name and replace last _ with .
        QString folderName = QFileInfo(cmd).fileName();
        int lastUnderscore = folderName.lastIndexOf('_');
        QString outputFile;
        if (lastUnderscore > 0) {
            outputFile = folderName.left(lastUnderscore) + "." + folderName.mid(lastUnderscore + 1);
        } else {
            // Fallback: use detected extension
            outputFile = folderName + "." + packer.detectExtension();
        }
        if (!packer.save(outputFile)) {
            printError(QString("Cannot write output file: %1").arg(outputFile));
            return 1;
        }
        cout << QString("Packed %1 files (%2 bytes) to %3\n")
                .arg(packer.count())
                .arg(packer.totalSize())
                .arg(outputFile);
        cout.flush();
        return 0;
    } else if (QFile::exists(cmd)) {
        // File dragged onto exe - unpack to folder named after file
        return cmdUnpack(QStringList() << cmd);
    } else {
        printError(QString("Unknown command: %1").arg(cmd));
        showUsage();
        return 1;
    }
}