document.addEventListener('DOMContentLoaded', init);

// State
let currentRange = 'day';
let chartInstances = {};

// Determine API Base URL from script location (robust for subpaths)
const scriptPath = document.currentScript ? document.currentScript.src : window.location.href;
const API_BASE = scriptPath.substring(0, scriptPath.lastIndexOf('/') + 1) + 'api/';

async function init() {
    setupControls();
    await loadDevices();
}

function setupControls() {
    // Range Buttons
    document.querySelectorAll('.range-btn').forEach(btn => {
        btn.addEventListener('click', (e) => {
            document.querySelectorAll('.range-btn').forEach(b => b.classList.remove('active'));
            e.target.classList.add('active');
            currentRange = e.target.dataset.range;
            loadData();
        });
    });

    // Device Select
    document.getElementById('deviceSelect').addEventListener('change', loadData);
}

/**
 * Fetch and populate device list
 */
async function loadDevices() {
    try {
        const res = await fetch(`${API_BASE}devices`);
        const devices = await res.json();

        const select = document.getElementById('deviceSelect');
        select.innerHTML = '';

        if (devices.length === 0) {
            const opt = document.createElement('option');
            opt.text = "No devices found";
            select.add(opt);
            return;
        }

        devices.forEach((dev, index) => {
            const opt = document.createElement('option');
            const label = `${dev.dev_name} - ${dev.port_name || 'Port ' + dev.port}`;
            opt.text = label;
            opt.value = JSON.stringify({ devName: dev.dev_name, port: dev.port, portName: dev.port_name });
            select.add(opt);

            // Auto-select first device
            if (index === 0) {
                select.value = opt.value;
            }
        });

        // Trigger initial load
        if (select.value) {
            loadData();
        }

    } catch (err) {
        console.error("Failed to load devices", err);
    }
}

/**
 * Fetch data and render charts
 */
async function loadData() {
    const select = document.getElementById('deviceSelect');
    if (!select.value) return;

    const { devName, port, portName } = JSON.parse(select.value);

    // Update Titles based on type
    const isLight = portName && portName.toLowerCase().includes('light');
    document.getElementById('levelFanTitle').innerText = isLight ? 'Brightness Levels' : 'Fan Speed Levels';

    try {
        const res = await fetch(`${API_BASE}history?devName=${encodeURIComponent(devName)}&port=${port}&range=${currentRange}`);
        const data = await res.json();
        renderCharts(data, isLight);
    } catch (err) {
        console.error("Failed to load history", err);
    }
}

function renderCharts(data, isLight) {
    const labels = data.map(d => new Date(d.timestamp).toLocaleString());

    // 1. Temp & Humidity
    const tempCtx = document.getElementById('tempHumChart').getContext('2d');
    updateChart('tempHum', tempCtx, labels, [
        {
            label: 'Temperature (°C)',
            data: data.map(d => d.temp_c),
            borderColor: '#ff6384',
            yAxisID: 'y'
        },
        {
            label: 'Humidity (%)',
            data: data.map(d => d.humidity),
            borderColor: '#36a2eb',
            yAxisID: 'y1'
        }
    ], {
        scales: {
            y: {
                type: 'linear',
                display: true,
                position: 'left',
                suggestedMin: 15,
                title: { display: true, text: 'Temp (°C)' }
            },
            y1: {
                type: 'linear',
                display: true,
                position: 'right',
                grid: { drawOnChartArea: false },
                suggestedMin: 30,
                suggestedMax: 80,
                title: { display: true, text: 'Humidity (%)' }
            }
        }
    });

    // 2. VPD
    const vpdCtx = document.getElementById('vpdChart').getContext('2d');
    updateChart('vpd', vpdCtx, labels, [{
        label: 'VPD (kPa)',
        data: data.map(d => d.vpd),
        borderColor: '#4bc0c0',
        backgroundColor: 'rgba(75, 192, 192, 0.2)',
        fill: true
    }]);

    // 3. Levels (Fan/Light)
    const levelCtx = document.getElementById('levelChart').getContext('2d');
    const levelLabel = isLight ? 'Brightness' : 'Fan Speed';
    const levelColor = isLight ? '#ffcd56' : '#9966ff'; // Yellow for light, Purple for fan

    updateChart('level', levelCtx, labels, [{
        label: levelLabel,
        data: data.map(d => d.fan_speed), // fan_speed used for generic level in DB
        borderColor: levelColor,
        backgroundColor: levelColor,
        stepped: true
    }], {
        scales: {
            y: {
                suggestedMin: 0,
                suggestedMax: 10,
                ticks: { stepSize: 1 }
            }
        }
    });
}

function updateChart(id, ctx, labels, datasets, extraOptions = {}) {
    if (chartInstances[id]) {
        chartInstances[id].destroy();
    }

    chartInstances[id] = new Chart(ctx, {
        type: 'line',
        data: {
            labels: labels,
            datasets: datasets.map(ds => ({ ...ds, borderWidth: 2, tension: 0.3, pointRadius: 1 }))
        },
        options: {
            responsive: true,
            maintainAspectRatio: false,
            interaction: {
                mode: 'index',
                intersect: false,
            },
            plugins: {
                legend: { position: 'top' }
            },
            ...extraOptions
        }
    });
}