#include "config_manager.h"
#include <QDir>
#include <QFile>
#include <QFileInfo>
#include <QDebug>
#include <QStandardPaths>
#include <QTimeZone>

ConfigManager::ConfigManager(QObject *parent)
    : QObject(parent)
{
    setDefaultValues();
}

QString ConfigManager::defaultSettingsPath()
{
    const QString configDirectory = QStandardPaths::writableLocation(QStandardPaths::AppConfigLocation);
    if (configDirectory.isEmpty())
    {
        qWarning() << "No application configuration directory is available";
        return QString();
    }

    return QDir(configDirectory).filePath("config.xml");
}

bool ConfigManager::loadSettings(const QString &filename)
{
    const QString settingsPath = filename.isEmpty() ? defaultSettingsPath() : filename;
    if (settingsPath.isEmpty())
    {
        return false;
    }

    QFile file(settingsPath);
    if (!file.exists())
    {
        qDebug() << "Config file does not exist, using defaults";
        return false;
    }

    if (!file.open(QIODevice::ReadOnly | QIODevice::Text))
    {
        qDebug() << "Cannot open config file for reading:" << file.errorString();
        return false;
    }

    QXmlStreamReader reader(&file);

    // Check if it's a valid XML file
    if (!reader.readNextStartElement() || reader.name() != QString("ClouckConfig"))
    {
        qDebug() << "Invalid config file format";
        file.close();
        return false;
    }

    // Read configuration values
    while (reader.readNextStartElement())
    {
        QString name = reader.name().toString();
        QString text = reader.readElementText();

        if (name == "FontColor")
        {
            m_fontColor = QColor(text);
        }
        else if (name == "BackgroundColor")
        {
            m_backgroundColor = QColor(text);
        }
        else if (name == "FontSize")
        {
            m_fontSize = text.toInt();
        }
        else if (name == "AlwaysOnTop")
        {
            m_alwaysOnTop = (text.toLower() == QString("true"));
        }
        else if (name == "WindowPosition")
        {
            // Parse position format: "x,y"
            QStringList coords = text.split(',');
            if (coords.size() == 2)
            {
                int x = coords[0].toInt();
                int y = coords[1].toInt();
                m_windowPosition = QPoint(x, y);
            }
        }
        else if (name == "WindowSize")
        {
            // Parse size format: "width,height"
            QStringList dims = text.split(',');
            if (dims.size() == 2)
            {
                int width = dims[0].toInt();
                int height = dims[1].toInt();
                m_windowSize = QSize(width, height);
            }
        }
        else if (name == "PrimaryTimeZone")
        {
            m_primaryTimeZoneId = text;
        }
        else if (name == "SecondaryTimeZone")
        {
            m_secondaryTimeZoneId = text;
        }
        else if (name == "BorderColor")
        {
            m_borderColor = QColor(text);
        }
        else if (name == "LocationFontSize")
        {
            m_locationFontSize = text.toInt();
        }
        else
        {
            reader.skipCurrentElement();
        }
    }

    file.close();

    if (reader.hasError())
    {
        qDebug() << "Error reading config file:" << reader.errorString();
        return false;
    }

    return true;
}

bool ConfigManager::saveSettings(const QString &filename)
{
    const QString settingsPath = filename.isEmpty() ? defaultSettingsPath() : filename;
    if (settingsPath.isEmpty())
    {
        return false;
    }

    const QFileInfo fileInfo(settingsPath);
    if (!QDir().mkpath(fileInfo.absolutePath()))
    {
        qDebug() << "Cannot create configuration directory:" << fileInfo.absolutePath();
        return false;
    }

    QFile file(settingsPath);
    if (!file.open(QIODevice::WriteOnly | QIODevice::Text))
    {
        qDebug() << "Cannot open config file for writing:" << file.errorString();
        return false;
    }

    QXmlStreamWriter writer(&file);
    writer.setAutoFormatting(true);
    writer.writeStartDocument();

    // Root element
    writer.writeStartElement("ClouckConfig");

    // Colors: store #RRGGBB when fully opaque, #AARRGGBB when translucent —
    // the XML stays close to what the user typed.
    const auto colorString = [](const QColor &color) {
        return color.alpha() == 255 ? color.name(QColor::HexRgb) : color.name(QColor::HexArgb);
    };
    writer.writeTextElement("FontColor", colorString(m_fontColor));
    writer.writeTextElement("BackgroundColor", colorString(m_backgroundColor));
    writer.writeTextElement("BorderColor", colorString(m_borderColor));

    // Font sizes
    writer.writeTextElement("FontSize", QString::number(m_fontSize));
    writer.writeTextElement("LocationFontSize", QString::number(m_locationFontSize));

    // Always on top
    writer.writeTextElement("AlwaysOnTop", m_alwaysOnTop ? "true" : "false");

    // Window position
    QString positionStr = QString("%1,%2")
                              .arg(m_windowPosition.x())
                              .arg(m_windowPosition.y());
    writer.writeTextElement("WindowPosition", positionStr);

    // Window size
    QString sizeStr = QString("%1,%2")
                          .arg(m_windowSize.width())
                          .arg(m_windowSize.height());
    writer.writeTextElement("WindowSize", sizeStr);

    writer.writeTextElement("PrimaryTimeZone", m_primaryTimeZoneId);
    writer.writeTextElement("SecondaryTimeZone", m_secondaryTimeZoneId);

    // Close root element
    writer.writeEndElement();

    writer.writeEndDocument();
    file.close();

    return true;
}

void ConfigManager::resetToDefaults()
{
    setDefaultValues();
}

bool ConfigManager::configExists(const QString &filename) const
{
    const QString settingsPath = filename.isEmpty() ? defaultSettingsPath() : filename;
    return !settingsPath.isEmpty() && QFile::exists(settingsPath);
}

void ConfigManager::setDefaultValues()
{
    m_fontColor = QColor(0, 255, 0);
    m_backgroundColor = QColor(0, 0, 0, 0);
    m_fontSize = 24;
    m_alwaysOnTop = true;

    // Calculate initial position: bottom-right corner of primary screen
    // Position will be set properly when widget is shown for the first time
    m_windowPosition = QPoint(-1, -1); // Special value indicating "not set yet"

    m_windowSize = QSize(240, 160); // Default clock size
    m_primaryTimeZoneId = QString::fromUtf8(QTimeZone::systemTimeZoneId());
    m_secondaryTimeZoneId = QStringLiteral("America/Los_Angeles");
    m_borderColor = QColor(0, 0, 0, 0);      // No border by default
    m_locationFontSize = 12;                  // Smaller city label under the time
}