#include "qbrainfuck.h"
#include "ui_qbrainfuck.h"

QBrainfuck::QBrainfuck(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::QBrainfuck)
{
    ui->setupUi(this);
}

QBrainfuck::~QBrainfuck()
{
    delete ui;
}

void QBrainfuck::on_encodeButton_clicked()
{
    QByteArray text = ui->textTextEdit->document()->toPlainText().toLatin1();

    // First pass : find decades/steps
    QList<char> decades; // Store the decades for initial loop
    decades.append(0);
    QList<char> array; // Store the program's memory
    array.append(0);
    QList<char> steps; // Store the steps to construct the program

    QByteArray::const_iterator textIterator;
    for (textIterator = text.constBegin(); textIterator != text.constEnd(); ++textIterator) {
        int max_diff = ui->maxSignsSpinBox->value()+1;
        QList<char>::iterator index;

        // Find nearest memory's case and store it
        QList<char>::iterator arrayIterator;
        for (arrayIterator = array.begin(); arrayIterator != array.end(); ++arrayIterator) {
            if (qAbs(*arrayIterator-*textIterator) < max_diff) {
                max_diff = qAbs(*arrayIterator-*textIterator);
                index = arrayIterator;
            }
        }

        // Add step and insert current value in the array, else add a decade if we don't find a case nearer than max_diff
        if (max_diff <= ui->maxSignsSpinBox->value()) {
            steps.append(*index);
            *index = *textIterator;
        } else {
            steps.append(qRound(*textIterator/(float)ui->decadesSpinBox->value())*ui->decadesSpinBox->value());
            decades.append(qRound(*textIterator/(float)ui->decadesSpinBox->value())*ui->decadesSpinBox->value());
            array.append(*textIterator);
        }
    }
    qSort(decades);

    // Second pass : write program
    QString program = "";

    for(int i = 0; i < ui->decadesSpinBox->value(); ++i) {
        program += "+";
    }

    program += "\[";

    QList<char>::iterator decadesIterator;
    for (decadesIterator = decades.begin()+1; decadesIterator != decades.end(); ++decadesIterator) {
        program += ">";
        for(int i = 0; i < *decadesIterator; i+=ui->decadesSpinBox->value()) {
            program += "+";
        }
    }
    for(int i = 0; i < decades.size()-1; ++i) {
        program += "<";
    }
    program += "-]";

    int prev_ptr = 0;

    QList<char>::const_iterator stepsIterator;
    textIterator = text.constBegin();
    for (stepsIterator = steps.constBegin(); stepsIterator != steps.constEnd(); ++stepsIterator) {
        int next_ptr = decades.indexOf(*stepsIterator);


        if(next_ptr > prev_ptr) {
            for(int i = 0; i < next_ptr-prev_ptr; ++i) {
                program += ">";
            }
        } else {
            for(int i = 0; i < prev_ptr-next_ptr; ++i) {
                program += "<";
            }
        }

        if(*textIterator > *stepsIterator) {
            for(int i = 0; i < *textIterator-*stepsIterator; ++i) {
                program += "+";
            }
        } else {
            for(int i = 0; i < *stepsIterator-*textIterator; ++i) {
                program += "-";
            }
        }

        program += ".";
        prev_ptr = next_ptr;
        decades[next_ptr] = *textIterator;
        ++textIterator;
    }

    ui->programTextEdit->setPlainText(program);
}

void QBrainfuck::on_decodeButton_clicked()
{
    ui->textTextEdit->setPlainText("");

    int ptr = 0;
    QByteArray text = ui->programTextEdit->document()->toPlainText().toLatin1();
    QByteArray array = QByteArray(ui->arraySpinBox->value(), (char)0);
    QByteArray input =  ui->inputLineEdit->text().toLatin1();
    QByteArray::const_iterator last_textIterator;
    QByteArray::const_iterator  inputIterator = input.constBegin();

    QByteArray::const_iterator textIterator;
    int loopCounter = 0;
    for (textIterator = text.constBegin(); textIterator != text.constEnd(); ++textIterator) {

        switch (*textIterator) {
        case '>':
            ptr++;
            if (ptr >= ui->arraySpinBox->value()) {
                QMessageBox::critical(this, "QBrainfuck", "Error: Pointer went upper than array's length");
                return;
            }
            break;
        case '<':
            ptr--;
            if (ptr < 0) {
                QMessageBox::critical(this, "QBrainfuck", "Error: Pointer went under 0");
                return;
            }
            break;
        case '+':
            array[ptr] = array.at(ptr) + 1;
            break;
        case '-':
            array[ptr] = array.at(ptr) - 1;
            break;
        case '.':
            ui->textTextEdit->insertPlainText(QString(array.at(ptr)));
            break;
        case ',':
            array[ptr] = *inputIterator;
            inputIterator++;
            break;
        case '[':
            last_textIterator = textIterator;
            loopCounter = 0;
            break;
        case ']':
            if(array.at(ptr)!=0) {
                textIterator = last_textIterator;
                loopCounter++;

                if (loopCounter >= ui->loopSpinBox->value()) {
                    QMessageBox::critical(this, "QBrainfuck", "Error: Loop too long");
                    return;
                }
            }
            break;
        }
    }
}

void QBrainfuck::on_motifButton_clicked()
{
    QString motif = ui->motifTextEdit->document()->toPlainText();
    QByteArray program =  ui->programTextEdit->document()->toPlainText().toLatin1();

    if (motif.contains(QRegExp(">|<|\\+|-|\\.|,|\\[|\\]"))) {
        QMessageBox::critical(this, "QBrainfuck", "Error: Motif contains Brainfuck characters");
        return;
    }

    QByteArray::const_iterator programIterator;
    for (programIterator = program.constBegin(); programIterator != program.constEnd(); ++programIterator) {
        switch (*programIterator) {
        case '>':
        case '<':
        case '+':
        case '-':
        case '.':
        case ',':
        case '[':
        case ']':
            int index = motif.indexOf(QRegExp(ui->regexLineEdit->text()));
            if (index==-1) {
                motif += *programIterator;
            } else {
                motif.replace(index, 1, *programIterator);
            }
            break;
        }
    }

    ui->resultTextEdit->setPlainText(motif);
}

void QBrainfuck::on_textTextEdit_textChanged()
{
    ui->textLabel->setText("Text length: " + QString().setNum(ui->textTextEdit->document()->toPlainText().length()));
}

void QBrainfuck::on_programTextEdit_textChanged()
{
    ui->programLabel->setText("Program length: " +  QString().setNum(ui->programTextEdit->document()->toPlainText().count(QRegExp(">|<|\\+|-|\\.|,|\\[|\\]"))));
}

void QBrainfuck::on_motifTextEdit_textChanged()
{
    ui->motifLabel->setText("Motif length: " + QString().setNum(ui->motifTextEdit->document()->toPlainText().count(QRegExp(ui->regexLineEdit->text()))));
}

void QBrainfuck::on_regexLineEdit_textChanged(const QString &arg1)
{
    on_motifTextEdit_textChanged();
}

void QBrainfuck::on_saveButton_clicked()
{
    QFileDialog dialog(this);
    dialog.setFileMode(QFileDialog::AnyFile);
    dialog.setNameFilter("Json Files (*.json);;Txt Files (*.txt)");
    dialog.setDefaultSuffix("json");
    dialog.setAcceptMode(QFileDialog::AcceptSave);

    if (dialog.exec()) {
        QFile saveFile(dialog.selectedFiles().first());

        if (!saveFile.open(QIODevice::WriteOnly)) {
            return;
        }

        if(dialog.selectedNameFilter() == "Json Files (*.json)") {
            QJsonObject jsonObject;

            jsonObject["text"] = ui->textTextEdit->document()->toPlainText();
            jsonObject["program"] = ui->programTextEdit->document()->toPlainText();
            jsonObject["motif"] = ui->motifTextEdit->document()->toPlainText();
            jsonObject["result"] = ui->resultTextEdit->document()->toPlainText();

            QJsonDocument jsonDoc(jsonObject);
            saveFile.write(jsonDoc.toJson());
        } else {
            saveFile.write(ui->textTextEdit->document()->toPlainText().toUtf8() + "\n\n");
            saveFile.write(ui->programTextEdit->document()->toPlainText().toUtf8() + "\n\n");
            saveFile.write(ui->motifTextEdit->document()->toPlainText().toUtf8() + "\n\n");
            saveFile.write(ui->resultTextEdit->document()->toPlainText().toUtf8() + "\n\n");
        }
    }
}

void QBrainfuck::on_loadButton_clicked()
{
    QFileDialog dialog(this);
    dialog.setFileMode(QFileDialog::AnyFile);
    dialog.setNameFilter("Json Files (*.json)");
    dialog.setDefaultSuffix("json");
    dialog.setAcceptMode(QFileDialog::AcceptOpen);

    if (dialog.exec()) {
        QFile loadFile(dialog.selectedFiles().first());

        if (!loadFile.open(QIODevice::ReadOnly)) {
            return;
        }

        QByteArray saveData = loadFile.readAll();

        QJsonDocument jsonDoc(QJsonDocument::fromJson(saveData));
        QJsonObject jsonObject = jsonDoc.object();

        ui->textTextEdit->setPlainText(jsonObject["text"].toString());
        ui->programTextEdit->setPlainText(jsonObject["program"].toString());
        ui->motifTextEdit->setPlainText(jsonObject["motif"].toString());
        ui->resultTextEdit->setPlainText(jsonObject["result"].toString());
    }
}