document.addEventListener('DOMContentLoaded', function() {
    // Sample data - in a real app this would come from an API
    const softwareData = [
        { id: 1, software: "CSI [Etabs, SAFE, SAP2000]", date: "July 9, 2020", cost: 12176.60, year: "2020" },
        { id: 2, software: "Plaxis", date: "September 1, 2020", cost: 5361.00, year: "2020" },
        { id: 3, software: "Tekla", date: "December 1, 2020", cost: 13503.40, year: "2020" },
        { id: 4, software: "CSI [Etabs, SAFE, SAP2000]", date: "July 9, 2021", cost: 11877.00, year: "2021" },
        { id: 5, software: "Plaxis", date: "September 1, 2021", cost: 5391.00, year: "2021" },
        { id: 6, software: "Tekla", date: "December 1, 2021", cost: 6868.60, year: "2021" },
        { id: 7, software: "CSI [Etabs, SAFE, SAP2000]", date: "August 10, 2022", cost: 13482.00, year: "2022" },
        { id: 8, software: "Plaxis", date: "September 5, 2022", cost: 5796.00, year: "2022" },
        { id: 9, software: "Tekla", date: "October 18, 2022", cost: 7130.37, year: "2022" },
        { id: 10, software: "CSI [Etabs, SAFE, SAP2000]", date: "July 4, 2023", cost: 11664.00, year: "2023" },
        { id: 11, software: "Plaxis", date: "September 21, 2023", cost: 6201.00, year: "2023" },
        { id: 12, software: "Tekla", date: "October 18, 2023", cost: 7792.20, year: "2023" },
        { id: 13, software: "CSI [Etabs, SAFE, SAP2000]", date: "July 4, 2024", cost: 11336.00, year: "2024" },
        { id: 14, software: "Plaxis", date: "September 18, 2024", cost: 7003.40, year: "2024" },
        { id: 15, software: "Tekla", date: "October 10, 2024", cost: 14963.91, year: "2024" },
        { id: 16, software: "CSI [Etabs, SAFE, SAP2000]", date: "May 22, 2025", cost: 11336.00, year: "2025" },
        { id: 17, software: "Unreal Engine", date: "September 6, 2024", cost: 2727.18, year: "2024" },
        { id: 18, software: "Plaxis", date: "September 18, 2025", cost: 7752.84, year: "2025" },
        { id: 19, software: "Tekla", date: "November 26, 2025", cost: 15467.10, year: "2025" },
        { id: 20, software: "Unreal Engine", date: "September 6, 2025", cost: 2744.62, year: "2025" }
    ];
    // Calculate summary stats
    const currentYear = new Date().getFullYear().toString();
    const currentYearSpend = softwareData
        .filter(item => item.year === currentYear)
        .reduce((sum, item) => sum + item.cost, 0);

    // Set current date
    const options = { year: 'numeric', month: 'long', day: 'numeric' };
    document.getElementById('current-date').textContent = new Date().toLocaleDateString('en-SG', options);
    document.getElementById('current-year').textContent = `SGD ${currentYearSpend.toLocaleString('en-SG', {minimumFractionDigits: 2, maximumFractionDigits: 2})}`;

const totalSpend = softwareData.reduce((sum, item) => sum + item.cost, 0);
    const years = [...new Set(softwareData.map(item => item.year))];
    const avgAnnual = totalSpend / years.length;
    
    // Find most expensive software
    const softwareGroups = {};
    softwareData.forEach(item => {
        if (!softwareGroups[item.software]) {
            softwareGroups[item.software] = 0;
        }
        softwareGroups[item.software] += item.cost;
    });
    const mostExpensive = Object.entries(softwareGroups).reduce((a, b) => a[1] > b[1] ? a : b);

    // Update summary cards
    document.getElementById('total-spend').textContent = `SGD ${totalSpend.toLocaleString('en-SG', {minimumFractionDigits: 2, maximumFractionDigits: 2})}`;
    document.getElementById('avg-annual').textContent = `SGD ${avgAnnual.toLocaleString('en-SG', {minimumFractionDigits: 2, maximumFractionDigits: 2})}`;
    document.getElementById('most-expensive').textContent = `${mostExpensive[0]} (SGD ${mostExpensive[1].toLocaleString('en-SG', {minimumFractionDigits: 2, maximumFractionDigits: 2})})`;

    // Create yearly chart
    const yearlyData = {};
    softwareData.forEach(item => {
        if (!yearlyData[item.year]) {
            yearlyData[item.year] = 0;
        }
        yearlyData[item.year] += item.cost;
    });

    const yearlyLabels = Object.keys(yearlyData).sort();
    const yearlyValues = yearlyLabels.map(year => yearlyData[year]);

    const ctx = document.getElementById('yearly-chart').getContext('2d');
    new Chart(ctx, {
        type: 'bar',
        data: {
            labels: yearlyLabels,
            datasets: [{
                label: 'Yearly Software Spend (SGD)',
                data: yearlyValues,
                backgroundColor: '#3B82F6',
                borderColor: '#2563EB',
                borderWidth: 1
            }]
        },
        options: {
            responsive: true,
            maintainAspectRatio: false,
            scales: {
                y: {
                    beginAtZero: true,
                    ticks: {
                        callback: function(value) {
                            return 'SGD ' + value.toLocaleString('en-SG');
                        }
                    }
                }
            },
            plugins: {
                tooltip: {
                    callbacks: {
                        label: function(context) {
                            return 'SGD ' + context.raw.toLocaleString('en-SG');
                        }
                    }
                }
            }
        }
    });
    // Populate current year's software table
    const currentYearTable = document.getElementById('current-year-table');
    const currentYearItems = softwareData.filter(item => item.year === currentYear);
    
    currentYearItems.forEach(item => {
        const row = document.createElement('tr');
        row.innerHTML = `
            <td class="px-6 py-4 whitespace-nowrap text-sm font-medium text-gray-900">${item.software}</td>
            <td class="px-6 py-4 whitespace-nowrap text-sm text-gray-500">${item.date}</td>
            <td class="px-6 py-4 whitespace-nowrap text-sm text-gray-500">${item.cost.toLocaleString('en-SG', {minimumFractionDigits: 2, maximumFractionDigits: 2})}</td>
        `;
        currentYearTable.appendChild(row);
    });

    // View toggle functionality
    document.getElementById('yearly-view').addEventListener('click', function() {
// In a real app, this would filter the table by year
        alert('Yearly view would show aggregated data by year');
    });

    document.getElementById('software-view').addEventListener('click', function() {
        // In a real app, this would group by software
        alert('Software view would show data grouped by software');
    });
});