// Safe Choices - Simulation Controller

// ===== STATE =====
let currentSimType = 'single';
let currentView = 'simulation';
let simulationResults = null;
let charts = {};

// ===== INITIALIZATION =====
document.addEventListener('DOMContentLoaded', () => {
    initializeApp();
});

function initializeApp() {
    setupEventListeners();
    updateEstimatedTime();
    initializeEmptyCharts();
}

function setupEventListeners() {
    // Number input constraints
    const numSimulations = document.getElementById('numSimulations');
    numSimulations.addEventListener('input', () => {
        numSimulations.value = Math.min(Math.max(parseInt(numSimulations.value) || 10, 10), 100);
        updateEstimatedTime();
    });

    const numFunds = document.getElementById('numFunds');
    numFunds.addEventListener('input', () => {
        numFunds.value = Math.min(Math.max(parseInt(numFunds.value) || 2, 2), 10);
        updateEstimatedTime();
    });

    // Target return custom input toggle
    const targetReturn = document.getElementById('targetReturn');
    const customTarget = document.getElementById('customTarget');
    targetReturn.addEventListener('change', () => {
        if (targetReturn.value === 'custom') {
            customTarget.classList.add('visible');
            customTarget.value = '15';
        } else {
            customTarget.classList.remove('visible');
        }
    });

    // Validate inputs on change
    document.querySelectorAll('.param-input').forEach(input => {
        input.addEventListener('input', validateInputs);
    });
}

// ===== VIEW SWITCHING =====
function selectView(view) {
    currentView = view;

    // Update toggle buttons
    document.querySelectorAll('.toggle-btn').forEach(btn => {
        btn.classList.toggle('active', btn.dataset.view === view);
    });

    // Show/hide content
    const simContent = document.getElementById('simulationContent');
    const methContent = document.getElementById('methodologyContent');

    if (view === 'simulation') {
        simContent.style.display = 'flex';
        methContent.style.display = 'none';
        document.querySelectorAll('.simulation-view-only').forEach(el => {
            el.classList.remove('hidden');
        });
    } else {
        simContent.style.display = 'none';
        methContent.style.display = 'block';
        document.querySelectorAll('.simulation-view-only').forEach(el => {
            el.classList.add('hidden');
        });
    }
}

// ===== SIMULATION TYPE SWITCHING =====
function selectSimulation(type) {
    currentSimType = type;

    // Update strategy cards
    document.querySelectorAll('.strategy-card').forEach(card => {
        card.classList.toggle('active', card.dataset.sim === type);
    });

    // Show/hide conditional parameters
    document.querySelectorAll('.threshold-only').forEach(el => {
        el.classList.toggle('visible', type === 'threshold');
    });

    document.querySelectorAll('.multi-only').forEach(el => {
        el.classList.toggle('visible', type === 'multi');
    });

    document.querySelectorAll('.kelly-only').forEach(el => {
        el.classList.toggle('visible', type === 'kelly');
    });

    updateEstimatedTime();
}

// ===== VALIDATION =====
function validateInputs() {
    const errors = [];

    const minProb7d = parseFloat(document.getElementById('minProb7d').value);
    const minProbCurrent = parseFloat(document.getElementById('minProbCurrent').value);

    if (minProb7d < 50 || minProb7d > 99) {
        errors.push('7-day probability must be between 50% and 99%');
    }
    if (minProbCurrent < 50 || minProbCurrent > 99) {
        errors.push('Current probability must be between 50% and 99%');
    }

    const runBtn = document.getElementById('runBtn');
    runBtn.disabled = errors.length > 0;

    return errors.length === 0;
}

// ===== TIME ESTIMATION =====
function updateEstimatedTime() {
    const numSims = parseInt(document.getElementById('numSimulations').value) || 100;
    const numFunds = currentSimType === 'multi' ? (parseInt(document.getElementById('numFunds').value) || 5) : 1;

    let baseTime = numSims * 0.05;
    if (currentSimType === 'multi') {
        baseTime *= Math.sqrt(numFunds);
    }

    const seconds = Math.max(2, Math.ceil(baseTime));
    const timeText = seconds < 60 ? `~${seconds}s` : `~${Math.ceil(seconds / 60)}min`;

    document.getElementById('estimatedTime').textContent = timeText;
}

// ===== SIMULATION EXECUTION =====
async function runSimulation() {
    if (!validateInputs()) return;

    const params = getSimulationParameters();

    showProgress();
    disableControls();

    try {
        const results = await callSimulationAPI(params);
        simulationResults = results;
        displayResults(results);
    } catch (error) {
        console.error('Simulation error:', error);
        alert('Simulation failed: ' + (error.message || 'Unknown error'));
    } finally {
        hideProgress();
        enableControls();
    }
}

function getSimulationParameters() {
    const params = {
        simType: currentSimType,
        startingCapital: parseFloat(document.getElementById('startingCapital').value),
        numSimulations: parseInt(document.getElementById('numSimulations').value),
        startDate: document.getElementById('startDate').value,
        maxDuration: parseInt(document.getElementById('maxDuration').value),
        minProb7d: parseFloat(document.getElementById('minProb7d').value) / 100,
        minProbCurrent: parseFloat(document.getElementById('minProbCurrent').value) / 100,
        daysBefore: parseInt(document.getElementById('daysBefore').value),
        investmentProbability: parseFloat(document.getElementById('investmentProbability').value),
        minVolume: parseFloat(document.getElementById('minVolume').value)
    };

    if (currentSimType === 'threshold') {
        const targetSelect = document.getElementById('targetReturn').value;
        if (targetSelect === 'custom') {
            params.targetReturn = parseFloat(document.getElementById('customTarget').value) / 100;
        } else {
            params.targetReturn = parseFloat(targetSelect) / 100;
        }
    }

    if (currentSimType === 'multi') {
        params.numFunds = parseInt(document.getElementById('numFunds').value);
    }

    if (currentSimType === 'kelly') {
        params.kellyFraction = parseFloat(document.getElementById('kellyFraction').value);
        params.edgeEstimate = document.getElementById('edgeEstimate').value;
    }

    return params;
}

async function callSimulationAPI(params) {
    const progressFill = document.getElementById('progressFill');
    const progressPercent = document.getElementById('progressPercent');
    const progressText = document.getElementById('progressText');

    progressText.textContent = 'Connecting to server...';
    progressFill.style.width = '10%';
    progressPercent.textContent = '10%';

    const requestBody = {
        simType: params.simType,
        startingCapital: params.startingCapital,
        numSimulations: params.numSimulations,
        startDate: params.startDate,
        maxDuration: params.maxDuration,
        minProb7d: params.minProb7d,
        minProbCurrent: params.minProbCurrent,
        daysBefore: params.daysBefore,
        investmentProbability: params.investmentProbability,
        minVolume: params.minVolume
    };

    if (params.targetReturn !== undefined) {
        requestBody.targetReturn = params.targetReturn;
    }
    if (params.numFunds !== undefined) {
        requestBody.numFunds = params.numFunds;
    }

    progressText.textContent = 'Running simulation...';
    progressFill.style.width = '30%';
    progressPercent.textContent = '30%';

    const response = await fetch('/api/simulate', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(requestBody)
    });

    if (!response.ok) {
        const errorData = await response.json().catch(() => ({ detail: response.statusText }));
        throw new Error(errorData.detail || `HTTP ${response.status}`);
    }

    progressText.textContent = 'Processing results...';
    progressFill.style.width = '80%';
    progressPercent.textContent = '80%';

    const results = await response.json();

    progressFill.style.width = '100%';
    progressPercent.textContent = '100%';
    progressText.textContent = 'Complete!';

    return results;
}

// ===== RESULTS DISPLAY =====
function displayResults(results) {
    const { summary, parameters, runs } = results;

    // Show results section
    const resultsSection = document.getElementById('resultsSection');
    resultsSection.classList.add('visible');
    resultsSection.scrollIntoView({ behavior: 'smooth', block: 'start' });

    // Calculate average return of survivors
    const survivors = runs.filter(r => !r.wentBust);
    const avgReturnSurvivors = survivors.length > 0
        ? survivors.reduce((sum, r) => sum + r.totalReturn, 0) / survivors.length
        : null;

    // Primary metrics
    updateMetric('avgReturn', summary.avgReturn, true);
    updateMetric('avgReturnSurvivors', avgReturnSurvivors, true);
    updateMetric('successRate', summary.positiveReturnRate);
    updateMetric('bustRate', summary.bustRate, false, true);

    // Risk metrics
    document.getElementById('volatility').textContent = formatPercentage(summary.returnVolatility);
    document.getElementById('maxDrawdown').textContent = formatPercentage(summary.maxDrawdown);
    document.getElementById('percentile5').textContent = formatPercentage(summary.return5th || -1);
    document.getElementById('percentile95').textContent = formatPercentage(summary.return95th || 0);

    // Type-specific stats
    if (parameters.simType === 'multi') {
        document.querySelectorAll('.multi-stats, .multi-chart').forEach(el => {
            el.classList.add('visible');
        });
        document.getElementById('avgSurvivingFunds').textContent =
            `${summary.avgSurvivingFunds?.toFixed(1) || '--'} / ${parameters.numFunds}`;
        document.getElementById('survivorshipRate').textContent = formatPercentage(summary.survivorshipRate || 0);
        document.getElementById('diversificationBenefit').textContent =
            summary.returnVolatility < 0.3 ? 'Positive' : 'Limited';
    } else {
        document.querySelectorAll('.multi-stats, .multi-chart').forEach(el => {
            el.classList.remove('visible');
        });
    }

    if (parameters.simType === 'threshold') {
        document.querySelectorAll('.threshold-stats').forEach(el => {
            el.classList.add('visible');
        });
        document.getElementById('targetReached').textContent = formatPercentage(summary.targetReachedRate || 0);
        document.getElementById('avgTimeToTarget').textContent =
            summary.avgTimeToTarget ? `${Math.round(summary.avgTimeToTarget)} days` : 'N/A';
        document.getElementById('vsNeverStop').textContent =
            (summary.targetReachedRate || 0) > 0.5 ? 'Better' : 'Similar';
    } else {
        document.querySelectorAll('.threshold-stats').forEach(el => {
            el.classList.remove('visible');
        });
    }

    if (parameters.simType === 'kelly') {
        document.querySelectorAll('.kelly-stats').forEach(el => {
            el.classList.add('visible');
        });
        document.getElementById('avgBetSize').textContent = formatPercentage(summary.avgBetSize || 0);
        document.getElementById('avgEdge').textContent = formatPercentage(summary.avgEdge || 0);
        document.getElementById('betsSkipped').textContent =
            summary.betsSkipped !== undefined ? `${summary.betsSkipped.toFixed(0)}` : '--';
    } else {
        document.querySelectorAll('.kelly-stats').forEach(el => {
            el.classList.remove('visible');
        });
    }

    // Generate charts
    generateCharts(results);
}

function updateMetric(id, value, showSign = false, isRisk = false) {
    const el = document.getElementById(id);
    el.textContent = formatPercentage(value);

    // Add color classes
    el.classList.remove('positive', 'negative', 'high-risk');
    if (isRisk) {
        if (value > 0.1) el.classList.add('high-risk');
    } else if (showSign) {
        if (value > 0.02) el.classList.add('positive');
        else if (value < -0.02) el.classList.add('negative');
    }
}

// ===== CHARTS =====
function initializeEmptyCharts() {
    charts.return = createEmptyChart('returnChart', 'bar');
    charts.capital = createEmptyChart('capitalChart', 'line');
    charts.survivorship = createEmptyChart('survivorshipChart', 'bar');
}

function createEmptyChart(canvasId, type) {
    const ctx = document.getElementById(canvasId).getContext('2d');
    return new Chart(ctx, {
        type: type,
        data: { labels: [], datasets: [] },
        options: getChartOptions(type)
    });
}

function generateCharts(results) {
    const { runs, parameters } = results;

    // Destroy existing charts
    Object.values(charts).forEach(chart => chart?.destroy());
    charts = {};

    // Return distribution
    charts.return = createReturnDistributionChart(runs);

    // Capital evolution
    charts.capital = createCapitalEvolutionChart(runs);

    // Survivorship (multi-fund only)
    if (parameters.simType === 'multi') {
        charts.survivorship = createSurvivorshipChart(runs, parameters.numFunds);
    } else {
        charts.survivorship = createEmptyChart('survivorshipChart', 'bar');
    }
}

function createReturnDistributionChart(runs) {
    const ctx = document.getElementById('returnChart').getContext('2d');
    const returns = runs.map(r => r.totalReturn * 100);

    const minReturn = Math.min(...returns);
    const maxReturn = Math.max(...returns);
    const binStart = Math.floor(minReturn / 10) * 10;
    const binEnd = Math.min(Math.ceil(maxReturn / 10) * 10, 200);

    const bins = [];
    for (let i = binStart; i <= binEnd; i += 5) bins.push(i);

    const binCounts = new Array(bins.length).fill(0);
    returns.forEach(ret => {
        for (let i = 0; i < bins.length - 1; i++) {
            if (ret >= bins[i] && ret < bins[i + 1]) {
                binCounts[i]++;
                break;
            }
        }
        if (ret >= bins[bins.length - 1]) binCounts[bins.length - 1]++;
    });

    return new Chart(ctx, {
        type: 'bar',
        data: {
            labels: bins.map(b => `${b}%`),
            datasets: [{
                label: 'Frequency',
                data: binCounts,
                backgroundColor: 'rgba(59, 130, 246, 0.6)',
                borderColor: 'rgba(59, 130, 246, 1)',
                borderWidth: 1,
                borderRadius: 4
            }]
        },
        options: getChartOptions('bar')
    });
}

function createCapitalEvolutionChart(runs) {
    const ctx = document.getElementById('capitalChart').getContext('2d');

    const colors = [
        { border: '#3b82f6', bg: 'rgba(59, 130, 246, 0.1)' },
        { border: '#10b981', bg: 'rgba(16, 185, 129, 0.1)' },
        { border: '#f59e0b', bg: 'rgba(245, 158, 11, 0.1)' },
        { border: '#ef4444', bg: 'rgba(239, 68, 68, 0.1)' },
        { border: '#8b5cf6', bg: 'rgba(139, 92, 246, 0.1)' }
    ];

    const sampleRuns = runs.slice(0, 5);
    const datasets = sampleRuns.map((run, i) => {
        let data = [];
        if (run.capitalHistory?.length > 0) {
            data = run.capitalHistory.map((item, idx) => ({
                x: typeof item === 'object' ? item.day : idx,
                y: typeof item === 'object' ? item.capital : item
            }));
        } else {
            data = [{ x: 0, y: 10000 }, { x: 1, y: run.finalCapital }];
        }

        return {
            label: `Run ${i + 1}`,
            data: data,
            borderColor: colors[i].border,
            backgroundColor: colors[i].bg,
            borderWidth: 2,
            fill: false,
            tension: 0.3,
            pointRadius: 0
        };
    });

    return new Chart(ctx, {
        type: 'line',
        data: { datasets },
        options: getChartOptions('line')
    });
}

function createSurvivorshipChart(runs, numFunds) {
    const ctx = document.getElementById('survivorshipChart').getContext('2d');
    const survivingCounts = runs.map(r => r.survivingFunds);

    const labels = [];
    const data = [];
    for (let i = 0; i <= numFunds; i++) {
        labels.push(i.toString());
        data.push(survivingCounts.filter(c => c === i).length);
    }

    return new Chart(ctx, {
        type: 'bar',
        data: {
            labels: labels,
            datasets: [{
                label: 'Frequency',
                data: data,
                backgroundColor: 'rgba(139, 92, 246, 0.6)',
                borderColor: 'rgba(139, 92, 246, 1)',
                borderWidth: 1,
                borderRadius: 4
            }]
        },
        options: getChartOptions('bar')
    });
}

function getChartOptions(type) {
    const baseOptions = {
        responsive: true,
        maintainAspectRatio: false,
        plugins: {
            legend: {
                display: type === 'line',
                labels: {
                    color: '#9ca3af',
                    font: { size: 11 },
                    usePointStyle: true,
                    padding: 16
                }
            }
        },
        scales: {
            x: {
                grid: { color: 'rgba(255, 255, 255, 0.05)' },
                ticks: { color: '#6b7280', font: { size: 10 } }
            },
            y: {
                grid: { color: 'rgba(255, 255, 255, 0.05)' },
                ticks: { color: '#6b7280', font: { size: 10 } }
            }
        }
    };

    if (type === 'line') {
        baseOptions.scales.x.type = 'linear';
    }

    return baseOptions;
}

// ===== EXPORT =====
function exportResults() {
    if (!simulationResults) return;

    const data = {
        timestamp: new Date().toISOString(),
        parameters: simulationResults.parameters,
        summary: simulationResults.summary,
        runs: simulationResults.runs
    };

    const blob = new Blob([JSON.stringify(data, null, 2)], { type: 'application/json' });
    const url = URL.createObjectURL(blob);

    const a = document.createElement('a');
    a.href = url;
    a.download = `safe_choices_${currentSimType}_${Date.now()}.json`;
    document.body.appendChild(a);
    a.click();
    document.body.removeChild(a);
    URL.revokeObjectURL(url);
}

// ===== UI HELPERS =====
function showProgress() {
    document.getElementById('progressPanel').classList.add('visible');
    document.getElementById('progressFill').style.width = '0%';
}

function hideProgress() {
    setTimeout(() => {
        document.getElementById('progressPanel').classList.remove('visible');
    }, 500);
}

function disableControls() {
    const runBtn = document.getElementById('runBtn');
    runBtn.disabled = true;
    runBtn.classList.add('running');
    document.querySelector('.run-text').textContent = 'Running...';
}

function enableControls() {
    const runBtn = document.getElementById('runBtn');
    runBtn.disabled = false;
    runBtn.classList.remove('running');
    document.querySelector('.run-text').textContent = 'Run Simulation';
}

function formatPercentage(value) {
    if (value === null || value === undefined || isNaN(value)) return '--';
    return `${(value * 100).toFixed(1)}%`;
}

// ===== UTILITY FUNCTIONS =====
function mean(arr) {
    return arr.reduce((a, b) => a + b, 0) / arr.length;
}

function median(arr) {
    const sorted = [...arr].sort((a, b) => a - b);
    const mid = Math.floor(sorted.length / 2);
    return sorted.length % 2 === 0 ? (sorted[mid - 1] + sorted[mid]) / 2 : sorted[mid];
}

function standardDeviation(arr) {
    const avg = mean(arr);
    return Math.sqrt(arr.reduce((sum, val) => sum + Math.pow(val - avg, 2), 0) / arr.length);
}

function percentile(arr, p) {
    const sorted = [...arr].sort((a, b) => a - b);
    const index = (p / 100) * (sorted.length - 1);
    const lower = Math.floor(index);
    const upper = Math.ceil(index);
    const weight = index % 1;
    return sorted[lower] * (1 - weight) + sorted[upper] * weight;
}