script.js

const STORAGE_KEY = "sportApp_Multi_v1";
const SETTINGS_KEY = "sportApp_Settings_v3";

const exercises = [
    "Liegestütze", "Kniebeugen", "Sit-ups", "Klimmzüge", "Burpees", 
];

let currentExercise = "Liegestütze";
let settings = { showAllHistory: false }; 
let myChart = null;

let chartFullLabels = [];
let chartFullData = [];

window.onload = function() {
    loadSettings();
    var today = new Date().toISOString().split('T')[0];
    var picker = document.getElementById("datePicker");
    if(picker) picker.value = today;
    
    updateStatusDisplay();
    showHistory();
    updateExerciseTitle();
};

function loadSettings() {
    var saved = JSON.parse(localStorage.getItem(SETTINGS_KEY));
    if(saved) settings = saved;
    var toggleHist = document.getElementById("showAllToggle");
    if(toggleHist) toggleHist.checked = settings.showAllHistory;
}

function updateSettings() {
    var toggleHist = document.getElementById("showAllToggle");
    settings.showAllHistory = toggleHist.checked;
    localStorage.setItem(SETTINGS_KEY, JSON.stringify(settings));
    showHistory(); 
}

// --- HAUPT LOGIK ---
function saveTraining() {
    var input = document.getElementById("repInput");
    var count = parseInt(input.value);
    if(!count) return;
    saveToStorage(count);
    input.value = ""; 
    input.focus();
}

function addTen() { saveToStorage(10); }

function openExerciseMenu() {
    var container = document.getElementById("exerciseListContainer");
    container.innerHTML = ""; 
    exercises.forEach(function(ex) {
        var btn = document.createElement("button");
        btn.className = "exercise-option";
        if(ex === currentExercise) btn.className += " selected";
        btn.innerText = ex;
        btn.onclick = function() { selectExercise(ex); };
        container.appendChild(btn);
    });
    document.getElementById("exerciseModal").style.display = "flex";
}

function selectExercise(name) {
    currentExercise = name;
    updateExerciseTitle();
    closeExerciseMenu();
    showHistory(); 
}

function closeExerciseMenu() { document.getElementById("exerciseModal").style.display = "none"; }
function openSettings() { document.getElementById("settingsModal").style.display = "flex"; }
function closeSettings() { document.getElementById("settingsModal").style.display = "none"; }
function updateExerciseTitle() { document.getElementById("currentExerciseTitle").innerText = currentExercise; }

function updateStatusDisplay() {
    var selectedDate = document.getElementById("datePicker").value;
    var today = new Date().toISOString().split('T')[0];
    var display = document.getElementById("statusDisplay");
    var dateObj = new Date(selectedDate);
    var germanDate = dateObj.toLocaleDateString('de-DE', {day: '2-digit', month: '2-digit'});

    if(selectedDate === today) {
        display.innerHTML = "Heute";
        display.style.color = "#888"; 
    } else {
        display.innerHTML = germanDate;
        display.style.color = "#d63384"; 
    }
}

// --- SPEICHERN ---
function saveToStorage(amountToAdd) {
    var selectedDate = document.getElementById("datePicker").value;
    var dateObj = new Date(selectedDate);
    var displayDate = dateObj.toLocaleDateString('de-DE');
    var history = JSON.parse(localStorage.getItem(STORAGE_KEY)) || [];

    var found = false;
    for (var i = 0; i < history.length; i++) {
        if (history[i].rawDate === selectedDate && history[i].exercise === currentExercise) {
            history[i].count = parseInt(history[i].count) + amountToAdd;
            found = true;
            break;
        }
    }

    if (!found) {
        history.unshift({ 
            rawDate: selectedDate, 
            displayDate: displayDate, 
            exercise: currentExercise, 
            count: amountToAdd 
        });
    }
    
    history.sort((a, b) => {
        if (b.rawDate !== a.rawDate) return new Date(b.rawDate) - new Date(a.rawDate);
        return a.exercise.localeCompare(b.exercise);
    });

    localStorage.setItem(STORAGE_KEY, JSON.stringify(history));
    showHistory();
}

function showHistory() {
    var listDiv = document.getElementById("list");
    var fullHistory = JSON.parse(localStorage.getItem(STORAGE_KEY)) || [];
    var selectedDate = document.getElementById("datePicker").value;

    listDiv.innerHTML = "";
    
    var displayList = fullHistory;
    if (!settings.showAllHistory) {
        displayList = fullHistory.filter(item => item.exercise === currentExercise);
    }

    if(displayList.length === 0) {
        listDiv.innerHTML = "<p style='color:#ccc; font-size:14px; text-align:center;'>Keine Einträge vorhanden</p>";
        return;
    }

    displayList.forEach(function(item) {
        var div = document.createElement("div");
        if (item.rawDate === selectedDate && (item.exercise === currentExercise || settings.showAllHistory)) {
            div.className = "entry active-day";
        } else {
            div.className = "entry";
        }
        div.innerHTML = `
            <div class="entry-left">
                <span class="entry-name">${item.exercise}</span>
                <span class="entry-date">${item.displayDate}</span>
            </div>
            <span class="entry-count">${item.count}</span>
        `;
        listDiv.appendChild(div);
    });
}

// --- ZOOMABLE CHART LOGIK ---
function openStats() {
    document.getElementById("statsModal").style.display = "flex";
    prepareChartData(); 
    renderChart('1M');
}

function closeStats() { document.getElementById("statsModal").style.display = "none"; }

function prepareChartData() {
    var fullHistory = JSON.parse(localStorage.getItem(STORAGE_KEY)) || [];
    var exerciseHistory = fullHistory.filter(item => item.exercise === currentExercise);
    
    chartFullLabels = [];
    chartFullData = [];

    var startDate = new Date();
    startDate.setMonth(startDate.getMonth() - 1);
    
    if (exerciseHistory.length > 0) {
        exerciseHistory.sort((a, b) => new Date(a.rawDate) - new Date(b.rawDate));
        startDate = new Date(exerciseHistory[0].rawDate);
    }

    var endDate = new Date();
    var dataMap = {};
    exerciseHistory.forEach(item => { dataMap[item.rawDate] = item.count; });

    for (var d = new Date(startDate); d <= endDate; d.setDate(d.getDate() + 1)) {
        var isoDate = d.toISOString().split('T')[0];
        var niceDate = d.toLocaleDateString('de-DE', {day: '2-digit', month: '2-digit'});
        chartFullLabels.push(niceDate);
        chartFullData.push(dataMap[isoDate] || 0);
    }
}

function renderChart(initialRange) {
    var ctx = document.getElementById('myChart').getContext('2d');
    
    if(myChart) { myChart.destroy(); }

    myChart = new Chart(ctx, {
        type: 'line',
        data: {
            labels: chartFullLabels,
            datasets: [{
                label: 'Wiederholungen',
                data: chartFullData,
                borderColor: '#007bff',
                backgroundColor: 'rgba(0, 123, 255, 0.1)',
                borderWidth: 2,
                tension: 0.1,
                fill: true,
                pointRadius: 3,
                pointHitRadius: 10
            }]
        },
        options: {
            responsive: true,
            maintainAspectRatio: false,
            scales: { y: { beginAtZero: true }, x: { ticks: { maxTicksLimit: 8 } } },
            plugins: { 
                legend: { display: false },
                zoom: {
                    zoom: {
                        wheel: { enabled: true },
                        pinch: { enabled: true },
                        mode: 'x',
                    },
                    pan: {
                        enabled: true,
                        mode: 'x',
                        modifierKey: null
                    }
                }
            }
        }
    });

    setChartRange(initialRange, document.querySelector('.chart-btn.active'));
}

function setChartRange(range, btnElement) {
    if(btnElement) {
        var btns = document.querySelectorAll(".chart-btn");
        btns.forEach(b => b.classList.remove("active"));
        btnElement.classList.add("active");
    }

    if (!myChart) return;

    var totalPoints = chartFullLabels.length;
    var visiblePoints = totalPoints;

    if (range === '1M') visiblePoints = 30;
    if (range === '3M') visiblePoints = 90;
    if (range === '6M') visiblePoints = 180;
    if (range === '1Y') visiblePoints = 365;
    if (range === 'ALL') visiblePoints = totalPoints;

    var minIndex = totalPoints - visiblePoints;
    if (minIndex < 0) minIndex = 0;
    var maxIndex = totalPoints - 1;

    myChart.options.scales.x.min = minIndex;
    myChart.options.scales.x.max = maxIndex;
    myChart.update();
}

function resetZoom() {
    if(myChart) myChart.resetZoom();
    setChartRange('1M', document.querySelector('.chart-btn'));
}

// --- EXPORT & IMPORT ---

function exportData() {
    var history = JSON.parse(localStorage.getItem(STORAGE_KEY)) || [];
    if (history.length === 0) { alert("Keine Daten vorhanden."); return; }
    var csvContent = "Datum;Uebung;Anzahl\n";
    history.forEach(function(row) { csvContent += `${row.displayDate};${row.exercise};${row.count}\n`; });
    var blob = new Blob(["\uFEFF" + csvContent], { type: 'text/csv;charset=utf-8;' });
    var url = URL.createObjectURL(blob);
    var link = document.createElement("a");
    link.setAttribute("href", url);
    link.setAttribute("download", "training_export.csv");
    document.body.appendChild(link);
    link.click();
    document.body.removeChild(link);
}

function importData(inputElement) {
    var file = inputElement.files[0];
    if (!file) return;

    var reader = new FileReader();
    reader.onload = function(e) {
        var text = e.target.result;
        var lines = text.split("\n");
        var importedCount = 0;
        var history = JSON.parse(localStorage.getItem(STORAGE_KEY)) || [];

        for (var i = 1; i < lines.length; i++) {
            var line = lines[i].trim();
            if (line === "") continue;
            var parts = line.split(";");
            if(parts.length < 3) parts = line.split(",");

            if (parts.length >= 3) {
                var csvDate = parts[0].trim(); 
                var csvExercise = parts[1].trim();
                var csvCount = parseInt(parts[2].trim());
                var dateParts = csvDate.split(".");
                if(dateParts.length === 3) {
                    var rawDate = `${dateParts[2]}-${dateParts[1]}-${dateParts[0]}`; 
                    var existingIndex = -1;
                    for(var j=0; j<history.length; j++) {
                        if(history[j].rawDate === rawDate && history[j].exercise === csvExercise) {
                            existingIndex = j;
                            break;
                        }
                    }
                    if(existingIndex > -1) {
                        history[existingIndex].count = csvCount;
                    } else {
                        history.push({
                            rawDate: rawDate,
                            displayDate: csvDate,
                            exercise: csvExercise,
                            count: csvCount
                        });
                    }
                    importedCount++;
                }
            }
        }
        localStorage.setItem(STORAGE_KEY, JSON.stringify(history));
        inputElement.value = ""; 
        alert(importedCount + " Einträge importiert!");
        showHistory();
        closeSettings();
    };
    reader.readAsText(file);
}

function clearAll() {
    if(confirm("ACHTUNG: Alle Daten werden gelöscht!")) {
        localStorage.removeItem(STORAGE_KEY);
        showHistory();
        closeSettings();
    }
}