#include "cashflow.h"
#include "ui_cashflow.h"
#include "settingsdialog.h"
#include <QMessageBox>
#include <QDebug>
#include <QDir>
#include <QStandardPaths>
#include <QFontDialog>
#include <QLocale>
#include <QFileDialog>
#include <QApplication>

CashFlow::CashFlow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::CashFlow)
    , currentTransactionId(-1)
    , currentRecurringId(-1)
    , startingBalance(0.0)
    , currentAmountFont("Courier New", 10)
    , weekStartDay(1) // Default to Monday
{
    ui->setupUi(this);
    
    // Initialize database
    database = new Database();
    
    // Try to open default database
    QString defaultDir = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation);
    QDir().mkpath(defaultDir);
    QString defaultPath = defaultDir + "/default.cashflo.sqlite";
    
    setupConnections();
    
    if (!openDatabase(defaultPath)) {
        QMessageBox::critical(this, "Database Error", "Failed to open default database: " + database->lastError());
        return;
    }
    
    // Regenerate all projections on startup to ensure they're current
    database->regenerateAllProjections();
    refreshView(); // Refresh to show new projection IDs
}

CashFlow::~CashFlow()
{
    delete database;
    delete ui;
}

void CashFlow::setupConnections() {
    // File menu
    connect(ui->actionNew, &QAction::triggered, this, &CashFlow::onNewFile);
    connect(ui->actionOpen, &QAction::triggered, this, &CashFlow::onOpenFile);
    connect(ui->actionQuit, &QAction::triggered, this, &CashFlow::onQuit);
    
    // Settings menu
    connect(ui->actionPreferences, &QAction::triggered, this, &CashFlow::onPreferences);
    
    // Transaction tab
    connect(ui->dateFromEdit, &QDateEdit::dateChanged, this, &CashFlow::onDateRangeChanged);
    connect(ui->dateToEdit, &QDateEdit::dateChanged, this, &CashFlow::onDateRangeChanged);
    connect(ui->periodCombo, QOverload<int>::of(&QComboBox::currentIndexChanged), this, &CashFlow::onPeriodChanged);
    connect(ui->accountFilterCombo, QOverload<int>::of(&QComboBox::currentIndexChanged), this, &CashFlow::onDateRangeChanged);
    connect(ui->showAccountBalancesCheck, &QCheckBox::stateChanged, this, &CashFlow::onDateRangeChanged);
    
    // Auto-save period and show balances settings
    connect(ui->periodCombo, QOverload<int>::of(&QComboBox::currentIndexChanged), this, [this]() {
        database->setSetting("default_period", QString::number(ui->periodCombo->currentIndex()));
    });
    connect(ui->showAccountBalancesCheck, &QCheckBox::stateChanged, this, [this]() {
        database->setSetting("show_account_balances", QString::number(ui->showAccountBalancesCheck->isChecked() ? 1 : 0));
    });
    
    connect(ui->transactionTable, &QTableWidget::itemSelectionChanged, this, &CashFlow::onTransactionSelected);
    connect(ui->saveBtn, &QPushButton::clicked, this, &CashFlow::onSaveTransaction);
    connect(ui->newBtn, &QPushButton::clicked, this, &CashFlow::onNewTransaction);
    connect(ui->deleteBtn, &QPushButton::clicked, this, &CashFlow::onDeleteTransaction);
    connect(ui->adjustmentBtn, &QPushButton::clicked, this, &CashFlow::onCreateAdjustment);
    
    // Transaction type change - grey out fields for reconciliation
    connect(ui->entryTypeCombo, QOverload<int>::of(&QComboBox::currentIndexChanged), this, [this](int index) {
        bool isReconciliation = (index == 2); // Reconciliation is index 2
        ui->entryCategoryCombo->setEnabled(!isReconciliation);
        ui->entryRecurringCombo->setEnabled(!isReconciliation);
        ui->entryOccurrenceEdit->setEnabled(!isReconciliation);
        ui->adjustmentBtn->setVisible(false); // Hide until we load a reconciliation
    });
    
    // Transaction entry recurring rule linking
    connect(ui->entryRecurringCombo, QOverload<int>::of(&QComboBox::currentIndexChanged), this, &CashFlow::onRecurringRuleChanged);
    connect(ui->entryDateEdit, &QDateEdit::dateChanged, this, &CashFlow::onTransactionDateChanged);
    
    // Set up Delete key shortcut for transaction table
    ui->deleteBtn->setShortcut(Qt::Key_Delete);
    
    // Color-code amount inputs
    connect(ui->entryAmountSpin, QOverload<double>::of(&QDoubleSpinBox::valueChanged), this, &CashFlow::updateAmountColors);
    connect(ui->recurringAmountSpin, QOverload<double>::of(&QDoubleSpinBox::valueChanged), this, &CashFlow::updateAmountColors);
    
    // Recurring tab
    connect(ui->recurringTable, &QTableWidget::itemSelectionChanged, this, &CashFlow::onRecurringSelected);
    connect(ui->saveRecurringBtn, &QPushButton::clicked, this, &CashFlow::onSaveRecurring);
    connect(ui->newRecurringBtn, &QPushButton::clicked, this, &CashFlow::onNewRecurring);
    connect(ui->deleteRecurringBtn, &QPushButton::clicked, this, &CashFlow::onDeleteRecurring);
    
    // Set up Delete key shortcut for recurring table
    ui->deleteRecurringBtn->setShortcut(QKeySequence(Qt::CTRL | Qt::Key_Delete));
}

void CashFlow::refreshView() {
    // Populate account filter dropdown with unique accounts
    // Block signals to prevent recursive refresh
    ui->accountFilterCombo->blockSignals(true);
    
    QString currentFilter = ui->accountFilterCombo->currentText();
    ui->accountFilterCombo->clear();
    ui->accountFilterCombo->addItem("All Accounts");
    
    // Get unique account names and categories
    QSet<QString> accounts;
    QSet<QString> categories;
    for (const Transaction &t : database->getAllTransactions()) {
        if (!t.account.isEmpty()) accounts.insert(t.account);
        if (!t.category.isEmpty()) categories.insert(t.category);
    }
    for (const RecurringRule &r : database->getAllRecurringRules()) {
        if (!r.account.isEmpty()) accounts.insert(r.account);
        if (!r.category.isEmpty()) categories.insert(r.category);
    }
    
    QStringList sortedAccounts = accounts.values();
    sortedAccounts.sort();
    ui->accountFilterCombo->addItems(sortedAccounts);
    
    // Populate entry form account combo
    ui->entryAccountCombo->blockSignals(true);
    QString currentAccount = ui->entryAccountCombo->currentText();
    ui->entryAccountCombo->clear();
    ui->entryAccountCombo->addItems(sortedAccounts);
    ui->entryAccountCombo->setCurrentText(currentAccount);
    ui->entryAccountCombo->blockSignals(false);
    
    // Populate entry form category combo
    ui->entryCategoryCombo->blockSignals(true);
    QString currentCategory = ui->entryCategoryCombo->currentText();
    ui->entryCategoryCombo->clear();
    QStringList sortedCategories = categories.values();
    sortedCategories.sort();
    ui->entryCategoryCombo->addItems(sortedCategories);
    ui->entryCategoryCombo->setCurrentText(currentCategory);
    ui->entryCategoryCombo->blockSignals(false);
    
    // Populate recurring rules combo
    populateRecurringRulesCombo();
    
    // Populate recurring rule account and category combos
    ui->recurringAccountCombo->blockSignals(true);
    ui->recurringAccountCombo->clear();
    ui->recurringAccountCombo->addItems(sortedAccounts);
    ui->recurringAccountCombo->blockSignals(false);
    
    ui->recurringCategoryCombo->blockSignals(true);
    ui->recurringCategoryCombo->clear();
    ui->recurringCategoryCombo->addItems(sortedCategories);
    ui->recurringCategoryCombo->blockSignals(false);
    
    // Restore previous selection if possible
    int index = ui->accountFilterCombo->findText(currentFilter);
    if (index >= 0) {
        ui->accountFilterCombo->setCurrentIndex(index);
    }
    
    ui->accountFilterCombo->blockSignals(false);
    
    refreshTransactionTable();
    refreshRecurringTable();
    calculateAndDisplayBalance();
}

void CashFlow::refreshTransactionTable() {
    QList<Transaction> allTransactions = getAllTransactionsInRange();
    
    ui->transactionTable->setRowCount(0);
    ui->transactionTable->setColumnCount(7);
    ui->transactionTable->setHorizontalHeaderLabels({"Date", "Amount", "Balance", "Account", "Category", "Description", "Type"});
    
    double runningBalance = startingBalance;
    QMap<QString, double> accountBalances; // Track per-account balances
    QDate currentPeriodEnd;
    QString periodLabel;
    int periodCount = 1;
    
    // Determine period type
    PeriodType periodType = static_cast<PeriodType>(ui->periodCombo->currentIndex());
    
    // Get first period end date
    if (!allTransactions.isEmpty()) {
        currentPeriodEnd = getPeriodEnd(allTransactions.first().date, periodType);
        periodLabel = getPeriodLabel(allTransactions.first().date, periodType, periodCount);
    }
    
    for (const Transaction &t : allTransactions) {
        // Check if we've crossed into a new period
        if (t.date > currentPeriodEnd) {
            // Insert period end row
            insertPeriodEndRow(periodLabel, runningBalance, accountBalances);
            
            // Move to next period
            periodCount++;
            currentPeriodEnd = getPeriodEnd(t.date, periodType);
            periodLabel = getPeriodLabel(t.date, periodType, periodCount);
        }
        
        // Update balances
        runningBalance += t.amount;
        accountBalances[t.account] += t.amount;
        
        // Insert transaction row
        int row = ui->transactionTable->rowCount();
        ui->transactionTable->insertRow(row);
        
        // Store ID in first column's data for retrieval later
        QTableWidgetItem *dateItem = new QTableWidgetItem(t.date.toString("MM/dd/yy"));
        dateItem->setData(Qt::UserRole, t.id);
        dateItem->setFlags(dateItem->flags() & ~Qt::ItemIsEditable);
        ui->transactionTable->setItem(row, 0, dateItem);
        
        // For reconciliation rows, show expected balance in amount column, variance in balance column
        double displayAmount = t.amount;
        double displayBalance = runningBalance;
        
        if (t.type == TransactionType::Reconciliation) {
            displayAmount = t.expectedBalance;  // Show what bank says
            displayBalance = t.expectedBalance - t.calculatedBalance; // Show variance
        }
        
        // Format amount with color, right-align, monospace
        QTableWidgetItem *amountItem = new QTableWidgetItem(QString("$%1").arg(formatCurrency(displayAmount)));
        amountItem->setTextAlignment(Qt::AlignRight | Qt::AlignVCenter);
        amountItem->setFont(currentAmountFont);
        amountItem->setFlags(amountItem->flags() & ~Qt::ItemIsEditable);
        if (displayAmount < 0) {
            amountItem->setForeground(QColor(200, 0, 0));
        } else {
            amountItem->setForeground(QColor(0, 150, 0));
        }
        ui->transactionTable->setItem(row, 1, amountItem);
        
        // Format balance with right-align, monospace
        QTableWidgetItem *balanceItem = new QTableWidgetItem(QString("$%1").arg(formatCurrency(displayBalance)));
        balanceItem->setTextAlignment(Qt::AlignRight | Qt::AlignVCenter);
        balanceItem->setFont(currentAmountFont);
        balanceItem->setFlags(balanceItem->flags() & ~Qt::ItemIsEditable);
        if (displayBalance < 0) {
            balanceItem->setForeground(QColor(200, 0, 0));
        }
        ui->transactionTable->setItem(row, 2, balanceItem);
        
        QTableWidgetItem *accountItem = new QTableWidgetItem(t.account);
        accountItem->setFlags(accountItem->flags() & ~Qt::ItemIsEditable);
        ui->transactionTable->setItem(row, 3, accountItem);
        
        QTableWidgetItem *categoryItem = new QTableWidgetItem(t.category);
        categoryItem->setFlags(categoryItem->flags() & ~Qt::ItemIsEditable);
        ui->transactionTable->setItem(row, 4, categoryItem);
        
        // For reconciliation, show calculated status in description
        QString displayDescription = t.description;
        if (t.type == TransactionType::Reconciliation) {
            double variance = t.expectedBalance - t.calculatedBalance;
            QString status = (qAbs(variance) < 0.01) ? "Balanced" : QString("Out of balance by $%1").arg(formatCurrency(variance));
            displayDescription = t.description.isEmpty() ? status : QString("%1 - %2").arg(t.description, status);
        }
        
        QTableWidgetItem *descItem = new QTableWidgetItem(displayDescription);
        descItem->setFlags(descItem->flags() & ~Qt::ItemIsEditable);
        ui->transactionTable->setItem(row, 5, descItem);
        
        QString typeLabel = "Estimated";
        if (t.type == TransactionType::Actual) typeLabel = "Actual";
        else if (t.type == TransactionType::Reconciliation) typeLabel = "Reconciliation";
        
        QTableWidgetItem *typeItem = new QTableWidgetItem(typeLabel);
        typeItem->setFlags(typeItem->flags() & ~Qt::ItemIsEditable);
        ui->transactionTable->setItem(row, 6, typeItem);
        
        // Color code: Actual=green, Estimated=yellow, Reconciliation=red if mismatch, green if balanced
        QColor rowColor;
        if (t.type == TransactionType::Reconciliation) {
            double variance = qAbs(t.expectedBalance - t.calculatedBalance);
            rowColor = (variance < 0.01) ? QColor(200, 255, 200) : QColor(255, 200, 200);
        } else {
            rowColor = t.type == TransactionType::Actual ? QColor(200, 255, 200) : QColor(255, 255, 200);
        }
        
        for (int col = 0; col < 7; col++) {
            if (ui->transactionTable->item(row, col)) {
                ui->transactionTable->item(row, col)->setBackground(rowColor);
            }
        }
    }
    
    // Insert final period end row
    if (!allTransactions.isEmpty()) {
        insertPeriodEndRow(periodLabel, runningBalance, accountBalances);
    }
    
    ui->transactionTable->resizeColumnsToContents();
    
    // Set minimum and optimal widths for specific columns
    ui->transactionTable->setColumnWidth(0, 100);  // Date
    ui->transactionTable->setColumnWidth(1, 100);  // Amount
    ui->transactionTable->setColumnWidth(2, 100);  // Balance
    ui->transactionTable->setColumnWidth(3, 120);  // Account
    ui->transactionTable->setColumnWidth(4, 120);  // Category
    ui->transactionTable->horizontalHeader()->setStretchLastSection(false);
    ui->transactionTable->setColumnWidth(5, 250);  // Description
    ui->transactionTable->setColumnWidth(6, 80);   // Type
}

QDate CashFlow::getPeriodEnd(const QDate &date, PeriodType periodType) {
    switch (periodType) {
        case Daily:
            return date;
        case Weekly: {
            // End on day before week start day
            int weekEndDay = (weekStartDay == 1) ? 7 : weekStartDay - 1;
            int currentDay = date.dayOfWeek();
            int daysUntilWeekEnd = (weekEndDay - currentDay + 7) % 7;
            if (daysUntilWeekEnd == 0 && currentDay != weekEndDay) {
                daysUntilWeekEnd = 7; // If we're past the end, go to next week's end
            }
            return date.addDays(daysUntilWeekEnd);
        }
        case Monthly:
            return QDate(date.year(), date.month(), date.daysInMonth());
        case Quarterly: {
            int quarter = (date.month() - 1) / 3;
            int lastMonthOfQuarter = (quarter + 1) * 3;
            QDate lastDayOfQuarter(date.year(), lastMonthOfQuarter, 1);
            return QDate(date.year(), lastMonthOfQuarter, lastDayOfQuarter.daysInMonth());
        }
    }
    return date;
}

QString CashFlow::getPeriodLabel(const QDate &date, PeriodType periodType, int count) {
    QDate periodStart = getPeriodStart(date, periodType);
    QDate periodEnd = getPeriodEnd(date, periodType);
    
    QString dateRange = QString("%1 - %2").arg(periodStart.toString("MM/dd/yy")).arg(periodEnd.toString("MM/dd/yy"));
    
    switch (periodType) {
        case Daily:
            return QString("DAY %1 (%2) END").arg(count).arg(date.toString("MM/dd/yy"));
        case Weekly:
            return QString("WEEK %1 END (%2)").arg(count).arg(dateRange);
        case Monthly:
            return QString("%1 END (%2)").arg(date.toString("MMMM yyyy").toUpper()).arg(dateRange);
        case Quarterly:
            return QString("Q%1 %2 END (%3)").arg((date.month() - 1) / 3 + 1).arg(date.year()).arg(dateRange);
    }
    return "";
}

QDate CashFlow::getPeriodStart(const QDate &date, PeriodType periodType) {
    switch (periodType) {
        case Daily:
            return date;
        case Weekly: {
            // Start on configured week start day (1=Monday, 7=Sunday)
            int currentDay = date.dayOfWeek(); // 1=Monday, 7=Sunday
            int daysFromWeekStart = (currentDay - weekStartDay + 7) % 7;
            return date.addDays(-daysFromWeekStart);
        }
        case Monthly:
            return QDate(date.year(), date.month(), 1);
        case Quarterly: {
            int quarter = (date.month() - 1) / 3;
            int firstMonthOfQuarter = quarter * 3 + 1;
            return QDate(date.year(), firstMonthOfQuarter, 1);
        }
    }
    return date;
}

void CashFlow::insertPeriodEndRow(const QString &label, double balance, const QMap<QString, double> &accountBalances) {
    int row = ui->transactionTable->rowCount();
    ui->transactionTable->insertRow(row);
    
    // Build display text with optional account balances
    QString displayText = QString("%1    Balance: $%2").arg(label).arg(formatCurrency(balance));
    
    if (ui->showAccountBalancesCheck->isChecked() && !accountBalances.isEmpty()) {
        QStringList accountTexts;
        QMapIterator<QString, double> it(accountBalances);
        while (it.hasNext()) {
            it.next();
            accountTexts.append(QString("%1: $%2").arg(it.key()).arg(formatCurrency(it.value())));
        }
        displayText += "    " + accountTexts.join("    ");
    }
    
    QTableWidgetItem *spanItem = new QTableWidgetItem(displayText);
    spanItem->setFont(QFont("Arial", 11, QFont::Bold));
    spanItem->setBackground(QColor(180, 180, 180));
    spanItem->setForeground(balance < 0 ? QColor(200, 0, 0) : QColor(0, 100, 0));
    spanItem->setTextAlignment(Qt::AlignLeft | Qt::AlignVCenter);
    spanItem->setFlags(spanItem->flags() & ~Qt::ItemIsSelectable); // Make non-selectable
    
    ui->transactionTable->setItem(row, 0, spanItem);
    
    // Span across all columns
    ui->transactionTable->setSpan(row, 0, 1, 7);
    
    // Make the row taller
    ui->transactionTable->setRowHeight(row, 30);
}

void CashFlow::refreshRecurringTable() {
    QList<RecurringRule> rules = database->getAllRecurringRules();
    
    ui->recurringTable->setRowCount(0);
    ui->recurringTable->setColumnCount(7);
    ui->recurringTable->setHorizontalHeaderLabels({"ID", "Name", "Frequency", "Amount", "Account", "Category", "Start Date"});
    ui->recurringTable->setEditTriggers(QAbstractItemView::NoEditTriggers);
    
    for (const RecurringRule &r : rules) {
        int row = ui->recurringTable->rowCount();
        ui->recurringTable->insertRow(row);
        
        ui->recurringTable->setItem(row, 0, new QTableWidgetItem(QString::number(r.id)));
        ui->recurringTable->setItem(row, 1, new QTableWidgetItem(r.name));
        
        QString freqStr;
        switch (r.frequency) {
            case RecurrenceFrequency::Daily: freqStr = "Daily"; break;
            case RecurrenceFrequency::Weekly: freqStr = "Weekly"; break;
            case RecurrenceFrequency::BiWeekly: freqStr = "Bi-Weekly"; break;
            case RecurrenceFrequency::Monthly: freqStr = "Monthly"; break;
            case RecurrenceFrequency::Yearly: freqStr = "Yearly"; break;
            default: freqStr = "None"; break;
        }
        ui->recurringTable->setItem(row, 2, new QTableWidgetItem(freqStr));
        
        // Amount with color coding, right-align, monospace
        QTableWidgetItem *amountItem = new QTableWidgetItem(QString("$%1").arg(formatCurrency(r.amount)));
        amountItem->setTextAlignment(Qt::AlignRight | Qt::AlignVCenter);
        amountItem->setFont(currentAmountFont);
        if (r.amount < 0) {
            amountItem->setForeground(QColor(200, 0, 0)); // Red for debits
        } else {
            amountItem->setForeground(QColor(0, 150, 0)); // Green for credits
        }
        ui->recurringTable->setItem(row, 3, amountItem);
        
        ui->recurringTable->setItem(row, 4, new QTableWidgetItem(r.account));
        ui->recurringTable->setItem(row, 5, new QTableWidgetItem(r.category));
        ui->recurringTable->setItem(row, 6, new QTableWidgetItem(r.startDate.toString("yyyy-MM-dd")));
    }
    
    ui->recurringTable->resizeColumnsToContents();
}

void CashFlow::calculateAndDisplayBalance() {
    QList<Transaction> allTransactions = getAllTransactionsInRange();
    
    double endBalance = startingBalance;
    for (const Transaction &t : allTransactions) {
        endBalance += t.amount;
    }
    
    ui->startBalanceLabel->setText(QString("Starting Balance: $%1").arg(formatCurrency(startingBalance)));
    ui->endBalanceLabel->setText(QString("Ending Balance: $%1").arg(formatCurrency(endBalance)));
    
    // Color code the ending balance
    if (endBalance < 0) {
        ui->endBalanceLabel->setStyleSheet("font-weight: bold; font-size: 12pt; color: red;");
    } else if (endBalance < 1000) {
        ui->endBalanceLabel->setStyleSheet("font-weight: bold; font-size: 12pt; color: orange;");
    } else {
        ui->endBalanceLabel->setStyleSheet("font-weight: bold; font-size: 12pt; color: green;");
    }
}

QList<Transaction> CashFlow::getAllTransactionsInRange() {
    QDate startDate = ui->dateFromEdit->date();
    QDate endDate = ui->dateToEdit->date();
    QString accountFilter = ui->accountFilterCombo->currentText();
    
    // Safety check
    if (accountFilter.isEmpty()) {
        accountFilter = "All Accounts";
    }
    
    // Get all transactions from database (includes both actual and projected)
    QList<Transaction> allTransactions = database->getTransactions(startDate, endDate);
    
    // Filter by account if not "All Accounts"
    if (accountFilter != "All Accounts") {
        QList<Transaction> filtered;
        for (const Transaction &t : allTransactions) {
            if (t.account == accountFilter) {
                filtered.append(t);
            }
        }
        allTransactions = filtered;
    }
    
    // Sort by date, then reconciliation always last, then by sort_order, then credits before debits
    std::sort(allTransactions.begin(), allTransactions.end(), 
              [](const Transaction &a, const Transaction &b) {
                  if (a.date != b.date) return a.date < b.date;
                  
                  // Reconciliation transactions always sort LAST on their date
                  if (a.type == TransactionType::Reconciliation && b.type != TransactionType::Reconciliation) return false;
                  if (a.type != TransactionType::Reconciliation && b.type == TransactionType::Reconciliation) return true;
                  
                  if (a.sortOrder != b.sortOrder) return a.sortOrder < b.sortOrder;
                  // Credits (positive amounts) before debits (negative amounts)
                  return a.amount > b.amount;
              });
    
    return allTransactions;
}

void CashFlow::onDateRangeChanged() {
    // Save date range to settings
    database->setSetting("date_from", ui->dateFromEdit->date().toString(Qt::ISODate));
    database->setSetting("date_to", ui->dateToEdit->date().toString(Qt::ISODate));
    
    refreshView();
}

void CashFlow::onPeriodChanged() {
    refreshView();
}

void CashFlow::onTransactionSelected() {
    QList<QTableWidgetItem*> selected = ui->transactionTable->selectedItems();
    if (selected.isEmpty()) {
        return;
    }
    
    int row = selected[0]->row();
    int id = ui->transactionTable->item(row, 0)->data(Qt::UserRole).toInt();
    
    // Load from database
    QList<Transaction> allTrans = database->getAllTransactions();
    for (const Transaction &t : allTrans) {
        if (t.id == id) {
            currentTransactionId = id;
            loadTransactionToEntry(t);
            QString typeLabel = (t.type == TransactionType::Estimated) ? "Estimated" : "Actual";
            ui->entryStatusLabel->setText(QString("Editing ID: %1 (%2)").arg(id).arg(typeLabel));
            return;
        }
    }
}

void CashFlow::onSaveTransaction() {
    // Skip validation if this is a new empty transaction being auto-saved
    bool isEmptyNew = (currentTransactionId == -1 && 
                       ui->entryAccountCombo->currentText().isEmpty() &&
                       ui->entryAmountSpin->value() == 0.0);
    
    if (!isEmptyNew) {
        // Validate required fields
        if (ui->entryAccountCombo->currentText().isEmpty()) {
            QMessageBox::warning(this, "Required Field", "Account is required.");
            return;
        }
        if (ui->entryAmountSpin->value() == 0.0) {
            QMessageBox::warning(this, "Required Field", "Amount cannot be zero.");
            return;
        }
    }
    
    Transaction t;
    t.id = currentTransactionId;
    t.date = ui->entryDateEdit->date();
    t.amount = ui->entryAmountSpin->value();
    t.account = ui->entryAccountCombo->currentText();
    t.category = ui->entryCategoryCombo->currentText();
    t.description = ui->entryDescriptionEdit->text();
    
    QString typeText = ui->entryTypeCombo->currentText();
    if (typeText == "Actual") t.type = TransactionType::Actual;
    else if (typeText == "Reconciliation") t.type = TransactionType::Reconciliation;
    else t.type = TransactionType::Estimated;
    
    // If this is a reconciliation checkpoint, calculate the variance
    if (t.type == TransactionType::Reconciliation) {
        // amount field holds the expected balance from bank
        t.expectedBalance = t.amount;
        // Calculate what we think the balance should be
        t.calculatedBalance = calculateBalanceUpTo(t.date, t.account);
        // Don't overwrite user's description - it's saved as-is
        // Category is irrelevant for reconciliation
        t.category = "";
        t.amount = 0; // Reconciliation rows don't affect balance
    }
    
    // Check if user manually linked to a recurring rule
    int manualRuleId = ui->entryRecurringCombo->currentData().toInt();
    QString manualOccurrenceKey = ui->entryOccurrenceEdit->text().trimmed();
    
    if (manualRuleId != -1 && !manualOccurrenceKey.isEmpty()) {
        // User manually linked to recurring rule
        t.recurringId = manualRuleId;
        t.occurrenceKey = manualOccurrenceKey;
        t.reconciled = true;
        // Try to get expected amount from the rule
        QList<RecurringRule> rules = database->getAllRecurringRules();
        for (const RecurringRule &rule : rules) {
            if (rule.id == manualRuleId) {
                t.expectedAmount = rule.amount;
                break;
            }
        }
    } else if (currentTransactionId != -1) {
        // Editing existing transaction - preserve existing reconciliation fields
        QList<Transaction> allTrans = database->getAllTransactions();
        for (const Transaction &existing : allTrans) {
            if (existing.id == currentTransactionId) {
                t.recurringId = existing.recurringId;
                t.occurrenceKey = existing.occurrenceKey;
                t.expectedAmount = existing.expectedAmount;
                t.expectedDate = existing.expectedDate;
                t.reconciled = existing.reconciled;
                // If user is converting Estimated to Actual, mark as reconciled
                if (existing.type == TransactionType::Estimated && t.type == TransactionType::Actual) {
                    t.reconciled = true;
                    if (t.expectedAmount == 0) {
                        t.expectedAmount = existing.amount; // Store original projected amount
                    }
                    if (!t.expectedDate.isValid()) {
                        t.expectedDate = existing.date; // Store original projected date
                    }
                }
                break;
            }
        }
    } else {
        // New manual transaction with no recurring link
        t.recurringId = -1;
        t.reconciled = false;
    }
    
    bool success;
    if (currentTransactionId == -1) {
        // New transaction
        success = database->addTransaction(t);
        if (success) {
            // Get the new ID and update currentTransactionId
            QList<Transaction> allTrans = database->getAllTransactions();
            if (!allTrans.isEmpty()) {
                currentTransactionId = allTrans.last().id;
            }
        }
    } else {
        // Update existing
        success = database->updateTransaction(t);
    }
    
    if (success) {
        // Recalculate all reconciliation checkpoints since balances may have changed
        recalculateAllReconciliations();
        
        ui->entryStatusLabel->setText("Saved!");
        refreshView();
    } else {
        QMessageBox::critical(this, "Error", "Failed to save: " + database->lastError());
    }
}

void CashFlow::onNewTransaction() {
    clearTransactionEntry();
    ui->entryDateEdit->setDate(QDate::currentDate());
    ui->entryDateEdit->setFocus();
}

void CashFlow::onDeleteTransaction() {
    if (currentTransactionId == -1) {
        QMessageBox::warning(this, "No Selection", "Please select a transaction to delete.");
        return;
    }
    
    if (QMessageBox::question(this, "Confirm Delete", 
        QString("Delete transaction ID %1?").arg(currentTransactionId)) == QMessageBox::Yes) {
        if (database->deleteTransaction(currentTransactionId)) {
            // Recalculate all reconciliation checkpoints since balances may have changed
            recalculateAllReconciliations();
            clearTransactionEntry();
            refreshView();
        } else {
            QMessageBox::critical(this, "Error", "Failed to delete: " + database->lastError());
        }
    }
}

void CashFlow::onCreateAdjustment() {
    // Get the current reconciliation details
    if (currentTransactionId == -1) return;
    
    QList<Transaction> allTrans = database->getAllTransactions();
    Transaction recon;
    bool found = false;
    
    for (const Transaction &t : allTrans) {
        if (t.id == currentTransactionId && t.type == TransactionType::Reconciliation) {
            recon = t;
            found = true;
            break;
        }
    }
    
    if (!found) return;
    
    double variance = recon.expectedBalance - recon.calculatedBalance;
    
    QString msg = QString("Create an adjustment transaction for $%1 to match the bank balance?\n\n"
                         "Bank says: $%2\n"
                         "We calculate: $%3\n"
                         "Adjustment needed: $%4")
                         .arg(formatCurrency(qAbs(variance)))
                         .arg(formatCurrency(recon.expectedBalance))
                         .arg(formatCurrency(recon.calculatedBalance))
                         .arg(formatCurrency(variance));
    
    if (QMessageBox::question(this, "Create Adjustment", msg) == QMessageBox::Yes) {
        // Create adjustment transaction on the same date, same account
        Transaction adj;
        adj.id = -1;
        adj.date = recon.date;
        adj.amount = variance;
        adj.account = recon.account;
        adj.category = "Adjustment";
        adj.description = "Balance adjustment to match bank statement";
        adj.type = TransactionType::Actual;
        adj.recurringId = -1;
        adj.reconciled = false;
        adj.sortOrder = 0; // Doesn't matter - reconciliation always sorts last
        
        if (database->addTransaction(adj)) {
            // Recalculate reconciliations and refresh
            recalculateAllReconciliations();
            refreshView();
            QMessageBox::information(this, "Success", "Adjustment transaction created.");
            ui->adjustmentBtn->setVisible(false); // Hide button since we're now balanced
        } else {
            QMessageBox::critical(this, "Error", "Failed to create adjustment: " + database->lastError());
        }
    }
}

void CashFlow::onRecurringSelected() {
    QList<QTableWidgetItem*> selected = ui->recurringTable->selectedItems();
    if (selected.isEmpty()) {
        return;
    }
    
    int row = selected[0]->row();
    int id = ui->recurringTable->item(row, 0)->text().toInt();
    
    QList<RecurringRule> rules = database->getAllRecurringRules();
    for (const RecurringRule &r : rules) {
        if (r.id == id) {
            loadRecurringToEntry(r);
            currentRecurringId = id;
            return;
        }
    }
}

void CashFlow::onSaveRecurring() {
    RecurringRule r;
    r.id = currentRecurringId;
    r.name = ui->recurringNameEdit->text();
    r.startDate = ui->recurringStartDateEdit->date();
    r.amount = ui->recurringAmountSpin->value();
    r.account = ui->recurringAccountCombo->currentText();
    r.category = ui->recurringCategoryCombo->currentText();
    r.description = ui->recurringDescriptionEdit->text();
    r.occurrences = -1; // Default to infinite
    
    QString freqStr = ui->recurringFrequencyCombo->currentText();
    if (freqStr == "Daily") {
        r.frequency = RecurrenceFrequency::Daily;
        r.dayOfWeek = -1;
        r.dayOfMonth = -1;
    }
    else if (freqStr == "Weekly") {
        r.frequency = RecurrenceFrequency::Weekly;
        r.dayOfWeek = r.startDate.dayOfWeek(); // Use the day of week from start date
        r.dayOfMonth = -1;
    }
    else if (freqStr == "Bi-Weekly") {
        r.frequency = RecurrenceFrequency::BiWeekly;
        r.dayOfWeek = r.startDate.dayOfWeek(); // Use the day of week from start date
        r.dayOfMonth = -1;
    }
    else if (freqStr == "Monthly") {
        r.frequency = RecurrenceFrequency::Monthly;
        r.dayOfWeek = -1;
        r.dayOfMonth = r.startDate.day(); // Use the day of month from start date
    }
    else if (freqStr == "Yearly") {
        r.frequency = RecurrenceFrequency::Yearly;
        r.dayOfWeek = -1;
        r.dayOfMonth = r.startDate.day();
    }
    
    bool success;
    if (currentRecurringId == -1) {
        success = database->addRecurringRule(r);
        if (success) {
            // Get the newly created rule ID to regenerate projections
            QList<RecurringRule> rules = database->getAllRecurringRules();
            if (!rules.isEmpty()) {
                RecurringRule newRule = rules.last();
                database->regenerateProjectionsForRule(newRule);
            }
        }
    } else {
        success = database->updateRecurringRule(r);
        if (success) {
            // Regenerate projections for updated rule
            database->regenerateProjectionsForRule(r);
        }
    }
    
    if (success) {
        refreshView();
        QMessageBox::information(this, "Success", "Recurring rule saved. Projections updated automatically.");
    } else {
        QMessageBox::critical(this, "Error", "Failed to save: " + database->lastError());
    }
}

void CashFlow::onNewRecurring() {
    clearRecurringEntry();
    ui->recurringStartDateEdit->setDate(QDate::currentDate());
    ui->recurringNameEdit->setFocus();
}

void CashFlow::onDeleteRecurring() {
    if (currentRecurringId == -1) {
        QMessageBox::warning(this, "No Selection", "Please select a recurring rule to delete.");
        return;
    }
    
    if (QMessageBox::question(this, "Confirm Delete", 
        "Delete this recurring rule and all its future projections?") == QMessageBox::Yes) {
        // Delete future projections first
        database->deleteProjectionsForRule(currentRecurringId);
        // Then delete the rule
        if (database->deleteRecurringRule(currentRecurringId)) {
            clearRecurringEntry();
            refreshView();
        } else {
            QMessageBox::critical(this, "Error", "Failed to delete: " + database->lastError());
        }
    }
}

void CashFlow::clearTransactionEntry() {
    currentTransactionId = -1;
    ui->entryDateEdit->setDate(QDate::currentDate());
    ui->entryAmountSpin->setValue(0.0);
    ui->entryAccountCombo->setCurrentText("");
    ui->entryCategoryCombo->setCurrentText("");
    ui->entryDescriptionEdit->clear();
    ui->entryTypeCombo->setCurrentIndex(0);
    ui->entryRecurringCombo->setCurrentIndex(0); // (None)
    ui->entryOccurrenceEdit->clear();
    ui->entryOccurrenceEdit->setEnabled(false);
    ui->entryStatusLabel->setText("(New transaction)");
    updateAmountColors();
}

void CashFlow::loadTransactionToEntry(const Transaction &t) {
    // Block signals to prevent auto-save while loading
    ui->entryDateEdit->blockSignals(true);
    ui->entryAmountSpin->blockSignals(true);
    ui->entryAccountCombo->blockSignals(true);
    ui->entryCategoryCombo->blockSignals(true);
    ui->entryDescriptionEdit->blockSignals(true);
    ui->entryTypeCombo->blockSignals(true);
    ui->entryRecurringCombo->blockSignals(true);
    ui->entryOccurrenceEdit->blockSignals(true);
    
    ui->entryDateEdit->setDate(t.date);
    
    // For reconciliation rows, load the expected balance into amount field
    double loadAmount = (t.type == TransactionType::Reconciliation) ? t.expectedBalance : t.amount;
    ui->entryAmountSpin->setValue(loadAmount);
    
    ui->entryAccountCombo->setCurrentText(t.account);
    ui->entryCategoryCombo->setCurrentText(t.category);
    ui->entryDescriptionEdit->setText(t.description);
    
    int typeIndex = 0; // Estimated
    if (t.type == TransactionType::Actual) typeIndex = 1;
    else if (t.type == TransactionType::Reconciliation) typeIndex = 2;
    ui->entryTypeCombo->setCurrentIndex(typeIndex);
    
    // Set recurring rule link if present
    if (t.recurringId != -1) {
        // Find and select the rule in combo
        for (int i = 0; i < ui->entryRecurringCombo->count(); i++) {
            if (ui->entryRecurringCombo->itemData(i).toInt() == t.recurringId) {
                ui->entryRecurringCombo->setCurrentIndex(i);
                break;
            }
        }
        ui->entryOccurrenceEdit->setText(t.occurrenceKey);
        ui->entryOccurrenceEdit->setEnabled(true);
    } else {
        ui->entryRecurringCombo->setCurrentIndex(0); // (None)
        ui->entryOccurrenceEdit->clear();
        ui->entryOccurrenceEdit->setEnabled(false);
    }
    
    ui->entryDateEdit->blockSignals(false);
    ui->entryAmountSpin->blockSignals(false);
    ui->entryAccountCombo->blockSignals(false);
    ui->entryCategoryCombo->blockSignals(false);
    ui->entryDescriptionEdit->blockSignals(false);
    ui->entryTypeCombo->blockSignals(false);
    ui->entryRecurringCombo->blockSignals(false);
    ui->entryOccurrenceEdit->blockSignals(false);
    
    // Show adjustment button if this is a reconciliation that's out of balance
    if (t.type == TransactionType::Reconciliation) {
        double variance = qAbs(t.expectedBalance - t.calculatedBalance);
        ui->adjustmentBtn->setVisible(variance >= 0.01);
    } else {
        ui->adjustmentBtn->setVisible(false);
    }
    
    updateAmountColors();
}

void CashFlow::clearRecurringEntry() {
    currentRecurringId = -1;
    ui->recurringNameEdit->clear();
    ui->recurringStartDateEdit->setDate(QDate::currentDate());
    ui->recurringAmountSpin->setValue(0.0);
    ui->recurringAccountCombo->setCurrentText("");
    ui->recurringCategoryCombo->setCurrentText("");
    ui->recurringDescriptionEdit->clear();
    ui->recurringFrequencyCombo->setCurrentIndex(3); // Default to Monthly
    updateAmountColors();
}

void CashFlow::loadRecurringToEntry(const RecurringRule &r) {
    ui->recurringNameEdit->setText(r.name);
    ui->recurringStartDateEdit->setDate(r.startDate);
    ui->recurringAmountSpin->setValue(r.amount);
    ui->recurringAccountCombo->setCurrentText(r.account);
    ui->recurringCategoryCombo->setCurrentText(r.category);
    ui->recurringDescriptionEdit->setText(r.description);
    
    int freqIndex = 3; // Default monthly
    switch (r.frequency) {
        case RecurrenceFrequency::Daily: freqIndex = 0; break;
        case RecurrenceFrequency::Weekly: freqIndex = 1; break;
        case RecurrenceFrequency::BiWeekly: freqIndex = 2; break;
        case RecurrenceFrequency::Monthly: freqIndex = 3; break;
        case RecurrenceFrequency::Yearly: freqIndex = 4; break;
        default: break;
    }
    ui->recurringFrequencyCombo->setCurrentIndex(freqIndex);
    updateAmountColors();
}

void CashFlow::updateAmountColors() {
    // Color code transaction amount
    if (ui->entryAmountSpin->value() < 0) {
        ui->entryAmountSpin->setStyleSheet("QDoubleSpinBox { color: rgb(200, 0, 0); font-weight: bold; }");
    } else if (ui->entryAmountSpin->value() > 0) {
        ui->entryAmountSpin->setStyleSheet("QDoubleSpinBox { color: rgb(0, 150, 0); font-weight: bold; }");
    } else {
        ui->entryAmountSpin->setStyleSheet("");
    }
    
    // Color code recurring amount
    if (ui->recurringAmountSpin->value() < 0) {
        ui->recurringAmountSpin->setStyleSheet("QDoubleSpinBox { color: rgb(200, 0, 0); font-weight: bold; }");
    } else if (ui->recurringAmountSpin->value() > 0) {
        ui->recurringAmountSpin->setStyleSheet("QDoubleSpinBox { color: rgb(0, 150, 0); font-weight: bold; }");
    } else {
        ui->recurringAmountSpin->setStyleSheet("");
    }
}

void CashFlow::loadSettings() {
    // Load settings from database
    QString fontFamily = database->getSetting("amount_font", "Courier New");
    int fontSize = database->getSetting("amount_font_size", "10").toInt();
    int defaultPeriod = database->getSetting("default_period", "2").toInt();
    bool showAccountBalances = database->getSetting("show_account_balances", "0").toInt();
    weekStartDay = database->getSetting("week_start_day", "1").toInt();
    
    // Load date range
    QDate today = QDate::currentDate();
    QString dateFromStr = database->getSetting("date_from", "");
    QString dateToStr = database->getSetting("date_to", "");
    
    QDate dateFrom = dateFromStr.isEmpty() ? QDate(today.year(), today.month(), 1) : QDate::fromString(dateFromStr, Qt::ISODate);
    QDate dateTo = dateToStr.isEmpty() ? today.addMonths(3) : QDate::fromString(dateToStr, Qt::ISODate);
    
    // Apply to member variables and main UI
    currentAmountFont = QFont(fontFamily, fontSize);
    ui->periodCombo->setCurrentIndex(defaultPeriod);
    ui->showAccountBalancesCheck->setChecked(showAccountBalances);
    ui->dateFromEdit->setDate(dateFrom);
    ui->dateToEdit->setDate(dateTo);
}

QString CashFlow::formatCurrency(double amount) const {
    QLocale locale;
    return locale.toString(amount, 'f', 2);
}

double CashFlow::calculateBalanceUpTo(const QDate &date, const QString &account) {
    QList<Transaction> allTrans = database->getAllTransactions();
    double balance = 0.0;
    
    // Sort by date to ensure proper ordering
    std::sort(allTrans.begin(), allTrans.end(), [](const Transaction &a, const Transaction &b) {
        if (a.date != b.date) return a.date < b.date;
        return a.sortOrder < b.sortOrder;
    });
    
    for (const Transaction &t : allTrans) {
        if (t.date > date) continue;
        if (!account.isEmpty() && t.account != account) continue;
        if (t.type == TransactionType::Reconciliation) continue; // Don't count reconciliation rows
        
        balance += t.amount;
    }
    
    return balance;
}

void CashFlow::recalculateAllReconciliations() {
    QList<Transaction> allTrans = database->getAllTransactions();
    
    for (Transaction &t : allTrans) {
        if (t.type == TransactionType::Reconciliation) {
            // Recalculate the calculated balance
            t.calculatedBalance = calculateBalanceUpTo(t.date, t.account);
            // Update in database
            database->updateTransaction(t);
        }
    }
}

bool CashFlow::openDatabase(const QString &filePath) {
    if (database->open(filePath)) {
        currentFilePath = filePath;
        QFileInfo fileInfo(filePath);
        setWindowTitle(QString("CashFlo - %1").arg(fileInfo.fileName()));
        
        loadSettings();
        
        clearTransactionEntry();
        clearRecurringEntry();
        refreshView();
        
        return true;
    }
    return false;
}

void CashFlow::onNewFile() {
    QString defaultDir = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation);
    QDir().mkpath(defaultDir);
    
    QString fileName = QFileDialog::getSaveFileName(
        this,
        "New CashFlo File",
        defaultDir,
        "CashFlo Files (*.cashflo.sqlite);;All Files (*)"
    );
    
    if (fileName.isEmpty()) {
        return;
    }
    
    // Ensure .cashflo.sqlite extension
    if (!fileName.endsWith(".cashflo.sqlite", Qt::CaseInsensitive)) {
        fileName += ".cashflo.sqlite";
    }
    
    // Remove file if it exists
    if (QFile::exists(fileName)) {
        QFile::remove(fileName);
    }
    
    // Close current database
    delete database;
    database = new Database();
    
    if (!openDatabase(fileName)) {
        QMessageBox::critical(this, "Error", "Failed to create new file: " + database->lastError());
    }
}

void CashFlow::onOpenFile() {
    QString defaultDir = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation);
    
    QString fileName = QFileDialog::getOpenFileName(
        this,
        "Open CashFlo File",
        defaultDir,
        "CashFlo Files (*.cashflo.sqlite);;All Files (*)"
    );
    
    if (fileName.isEmpty()) {
        return;
    }
    
    // Close current database
    delete database;
    database = new Database();
    
    if (!openDatabase(fileName)) {
        QMessageBox::critical(this, "Error", "Failed to open file: " + database->lastError());
    }
}

void CashFlow::onQuit() {
    QApplication::quit();
}

void CashFlow::onPreferences() {
    SettingsDialog dialog(database, this);
    if (dialog.exec() == QDialog::Accepted) {
        // Reload settings
        currentAmountFont = dialog.getCurrentAmountFont();
        weekStartDay = dialog.getWeekStartDay();
        loadSettings();
        refreshView();
    }
}

void CashFlow::populateRecurringRulesCombo() {
    ui->entryRecurringCombo->clear();
    ui->entryRecurringCombo->addItem("(None)", -1);
    
    QList<RecurringRule> rules = database->getAllRecurringRules();
    for (const RecurringRule &rule : rules) {
        QString label = QString("%1 (%2)").arg(rule.name).arg(
            rule.frequency == RecurrenceFrequency::Daily ? "Daily" :
            rule.frequency == RecurrenceFrequency::Weekly ? "Weekly" :
            rule.frequency == RecurrenceFrequency::BiWeekly ? "Bi-weekly" :
            rule.frequency == RecurrenceFrequency::Monthly ? "Monthly" :
            rule.frequency == RecurrenceFrequency::Yearly ? "Yearly" : "Unknown"
        );
        ui->entryRecurringCombo->addItem(label, rule.id);
    }
}

QString CashFlow::generateOccurrenceKey(const QDate &date, RecurrenceFrequency frequency) const {
    if (frequency == RecurrenceFrequency::Daily) {
        return date.toString("yyyy-MM-dd");
    } else if (frequency == RecurrenceFrequency::Weekly || frequency == RecurrenceFrequency::BiWeekly) {
        return QString("%1-W%2").arg(date.year()).arg(date.weekNumber(), 2, 10, QChar('0'));
    } else if (frequency == RecurrenceFrequency::Monthly) {
        return date.toString("yyyy-MM");
    } else if (frequency == RecurrenceFrequency::Yearly) {
        return QString::number(date.year());
    }
    return QString();
}

void CashFlow::updateOccurrenceKey() {
    int ruleId = ui->entryRecurringCombo->currentData().toInt();
    if (ruleId == -1) {
        ui->entryOccurrenceEdit->clear();
        ui->entryOccurrenceEdit->setEnabled(false);
        return;
    }
    
    ui->entryOccurrenceEdit->setEnabled(true);
    
    // Find the rule to get its frequency
    QList<RecurringRule> rules = database->getAllRecurringRules();
    for (const RecurringRule &rule : rules) {
        if (rule.id == ruleId) {
            QString occurrenceKey = generateOccurrenceKey(ui->entryDateEdit->date(), rule.frequency);
            ui->entryOccurrenceEdit->setText(occurrenceKey);
            break;
        }
    }
}

void CashFlow::onRecurringRuleChanged() {
    updateOccurrenceKey();
}

void CashFlow::onTransactionDateChanged() {
    // Update occurrence key if a recurring rule is selected
    if (ui->entryRecurringCombo->currentData().toInt() != -1) {
        updateOccurrenceKey();
    }
}