{% extends "base.html" %}

{% block title %}Edit NeetPrep Questions{% endblock %}

{% block head %}
<style>
    /* Style for rendered question HTML */
    #topic_q_text img {
        max-width: 100%;
        height: auto;
        border-radius: 4px;
    }
    #topic_q_text p {
        margin-bottom: 0.5rem;
    }
    #topic_q_text {
        font-size: 0.95rem;
        line-height: 1.5;
    }
    /* Truncate table cell text */
    .question-text-cell {
        max-width: 300px;
        overflow: hidden;
        text-overflow: ellipsis;
        white-space: nowrap;
    }
    /* Range toggles */
    .range-toggle {
        transition: all var(--transition-fast);
        border-radius: 50px;
    }
    .range-toggle:hover {
        transform: translateY(-1px);
    }
    .range-toggle.active { transform: scale(1.02); box-shadow: 0 0 8px rgba(255,255,255,0.2); }
    .range-toggle.active.btn-outline-primary { background: var(--accent-primary); color: #fff; }
    .range-toggle.active.btn-outline-warning { background: var(--accent-warning); color: #000; }
    .range-toggle.active.btn-outline-info { background: var(--accent-info); color: #000; }
    /* Range slider styling */
    .range-slider-row { background: var(--bg-elevated); border-radius: 10px; padding: 12px; margin-bottom: 10px; transition: all var(--transition-fast); }
    .range-slider-row:hover { background: var(--bg-hover); }
    .dual-range-container { position: relative; height: 40px; }
    .dual-range-track { position: absolute; top: 50%; left: 0; right: 0; height: 8px; background: var(--border-subtle); border-radius: 4px; transform: translateY(-50%); }
    .dual-range-highlight { position: absolute; top: 50%; height: 8px; background: linear-gradient(90deg, var(--accent-primary), var(--accent-info)); border-radius: 4px; transform: translateY(-50%); }
    .dual-range-container input[type="range"] { position: absolute; top: 0; left: 0; width: 100%; height: 100%; -webkit-appearance: none; background: transparent; pointer-events: none; }
    .dual-range-container input[type="range"]::-webkit-slider-thumb { -webkit-appearance: none; width: 24px; height: 24px; background: #fff; border: 3px solid var(--accent-primary); border-radius: 50%; cursor: pointer; pointer-events: auto; box-shadow: var(--shadow-sm); transition: transform var(--transition-fast); }
    .dual-range-container input[type="range"]::-webkit-slider-thumb:hover { transform: scale(1.15); }
    .dual-range-container input[type="range"]::-moz-range-thumb { width: 24px; height: 24px; background: #fff; border: 3px solid var(--accent-primary); border-radius: 50%; cursor: pointer; pointer-events: auto; box-shadow: var(--shadow-sm); }
    /* Card styling */
    .edit-card {
        border-radius: 12px;
        overflow: hidden;
    }
    .edit-card .card-header {
        background: linear-gradient(180deg, var(--bg-card), var(--bg-dark));
    }
</style>
{% endblock %}

{% block content %}
<div class="container mt-5">
    <div class="card bg-dark text-white edit-card">
        <div class="card-header d-flex justify-content-between align-items-center flex-wrap gap-2">
            <h2><i class="bi bi-pencil-square me-2"></i>Edit NeetPrep Questions</h2>
            <div class="d-flex gap-2">
                <button type="button" class="btn btn-warning btn-pill" data-bs-toggle="modal" data-bs-target="#manualClassificationModal">
                    <i class="bi bi-list-check"></i> Manual Classification
                </button>
                <a href="/neetprep" class="btn btn-outline-light btn-pill">Back to NeetPrep Home</a>
            </div>
        </div>
        <div class="card-body">
            <!-- Filter Form -->
            <div class="row mb-3">
                <div class="col-md-6">
                    <input type="text" id="search-input" class="form-control bg-dark text-white" placeholder="Search questions...">
                </div>
                <div class="col-md-4">
                    <select id="topic-filter" class="form-select bg-dark text-white">
                        <option value="all">All Topics</option>
                        <option value="Unclassified" selected>Unclassified Only</option>
                        {% for topic in topics %}
                        {% if topic != 'Unclassified' %}
                        <option value="{{ topic }}">{{ topic }}</option>
                        {% endif %}
                        {% endfor %}
                    </select>
                </div>
            </div>

            <!-- Questions Table -->
            <div class="table-responsive">
                <table class="table table-dark table-hover">
                    <thead>
                        <tr>
                            <th style="width: 40px;">#</th>
                            <th>Question Text</th>
                            <th>Topic</th>
                            <th>Subject</th>
                            <th>Action</th>
                        </tr>
                    </thead>
                    <tbody id="questions-table-body">
                        {% for q in questions %}
                        <tr data-topic="{{ q.topic }}" data-id="{{ q.id }}" data-index="{{ loop.index }}" data-html="{{ q.question_text | e }}">
                            <td>{{ loop.index }}</td>
                            <td class="question-text-cell">{{ q.question_text_plain[:100] }}{% if q.question_text_plain|length > 100 %}...{% endif %}</td>
                            <td class="topic-cell">{{ q.topic }}</td>
                            <td class="subject-cell">{{ q.subject }}</td>
                            <td>
                                <button class="btn btn-sm btn-primary edit-btn"
                                        data-id="{{ q.id }}"
                                        data-topic="{{ q.topic }}"
                                        data-subject="{{ q.subject }}"
                                        data-bs-toggle="modal"
                                        data-bs-target="#editModal">
                                    Edit
                                </button>
                            </td>
                        </tr>
                        {% endfor %}
                    </tbody>
                </table>
            </div>
        </div>
    </div>
</div>

<!-- Edit Modal (Single Question) -->
<div class="modal fade" id="editModal" tabindex="-1" aria-labelledby="editModalLabel" aria-hidden="true">
    <div class="modal-dialog">
        <div class="modal-content bg-dark text-white">
            <div class="modal-header">
                <h5 class="modal-title" id="editModalLabel">Edit Question Metadata</h5>
                <button type="button" class="btn-close btn-close-white" data-bs-dismiss="modal" aria-label="Close"></button>
            </div>
            <div class="modal-body">
                <form id="edit-form">
                    <input type="hidden" id="edit-question-id">
                    <div class="mb-3">
                        <label for="edit-topic" class="form-label">Topic</label>
                        <input type="text" class="form-control bg-secondary text-white" id="edit-topic" required>
                    </div>
                    <div class="mb-3">
                        <label for="edit-subject" class="form-label">Subject</label>
                        <input type="text" class="form-control bg-secondary text-white" id="edit-subject" required>
                    </div>
                </form>
            </div>
            <div class="modal-footer">
                <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Close</button>
                <button type="button" class="btn btn-primary" id="save-changes-btn">Save changes</button>
            </div>
        </div>
    </div>
</div>

<!-- Manual Classification Setup Modal -->
<div class="modal fade" id="manualClassificationModal" tabindex="-1">
    <div class="modal-dialog modal-lg">
        <div class="modal-content bg-dark text-white">
            <div class="modal-header border-secondary">
                <h5 class="modal-title"><i class="bi bi-list-check me-2"></i>Quick Classification</h5>
                <button type="button" class="btn-close btn-close-white" data-bs-dismiss="modal"></button>
            </div>
            <div class="modal-body">
                <div class="alert alert-info border-0 mb-3">
                    <i class="bi bi-lightning-fill me-2"></i>
                    <span id="visible-count-info">Classify filtered questions with AI-powered suggestions.</span>
                </div>

                <!-- Quick Range Toggles -->
                <div class="mb-3">
                    <label class="form-label">Quick Select</label>
                    <div class="d-flex flex-wrap gap-2">
                        <button type="button" class="btn btn-outline-primary range-toggle active" data-range="all">
                            <i class="bi bi-collection me-1"></i>All Visible
                        </button>
                        <button type="button" class="btn btn-outline-warning range-toggle" data-range="unclassified">
                            <i class="bi bi-question-circle me-1"></i>Unclassified
                        </button>
                        <button type="button" class="btn btn-outline-info range-toggle" data-range="custom">
                            <i class="bi bi-sliders me-1"></i>Custom Range
                        </button>
                    </div>
                </div>

                <!-- Custom Range Slider UI -->
                <div id="custom-range-container" class="d-none">
                    <div class="card bg-secondary mb-3">
                        <div class="card-body">
                            <div class="d-flex justify-content-between align-items-center mb-2">
                                <label class="form-label mb-0">Select Question Ranges</label>
                                <button type="button" class="btn btn-sm btn-success" onclick="addRangeSlider()">
                                    <i class="bi bi-plus-lg me-1"></i>Add Range
                                </button>
                            </div>

                            <div id="range-sliders-container">
                                <!-- Range sliders will be added here -->
                            </div>

                            <div class="mt-3 p-2 bg-dark rounded">
                                <small class="text-muted">Selected: </small>
                                <span id="selected-ranges-display" class="text-info fw-bold">None</span>
                                <small class="text-muted ms-2">(<span id="selected-count">0</span> questions)</small>
                            </div>
                        </div>
                    </div>

                    <!-- Preview Section -->
                    <div class="row" id="range-preview-section">
                        <div class="col-6">
                            <div class="card bg-secondary">
                                <div class="card-header py-1 text-center">
                                    <small class="text-success"><i class="bi bi-arrow-right-circle me-1"></i>Start</small>
                                </div>
                                <div class="card-body p-2">
                                    <div id="preview-start-text" class="small" style="max-height: 60px; overflow: hidden;"></div>
                                    <div class="mt-1"><span class="badge bg-primary" id="preview-start-num">#1</span></div>
                                </div>
                            </div>
                        </div>
                        <div class="col-6">
                            <div class="card bg-secondary">
                                <div class="card-header py-1 text-center">
                                    <small class="text-danger"><i class="bi bi-arrow-left-circle me-1"></i>End</small>
                                </div>
                                <div class="card-body p-2">
                                    <div id="preview-end-text" class="small" style="max-height: 60px; overflow: hidden;"></div>
                                    <div class="mt-1"><span class="badge bg-primary" id="preview-end-num">#1</span></div>
                                </div>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
            <div class="modal-footer border-secondary">
                <button type="button" class="btn btn-lg btn-primary w-100" onclick="startManualClassification()">
                    <i class="bi bi-play-fill me-2"></i>Start Classification
                </button>
            </div>
        </div>
    </div>
</div>

<!-- Topic Selection Wizard Modal -->
<div class="modal fade" id="topicSelectionModal" tabindex="-1" data-bs-backdrop="static" data-bs-keyboard="false">
    <div class="modal-dialog modal-lg modal-dialog-centered">
        <div class="modal-content bg-dark text-white border-secondary">
            <div class="modal-header border-secondary py-2">
                <div class="d-flex align-items-center gap-3">
                    <span class="badge bg-primary fs-6" id="topic_q_num">#1</span>
                    <div class="progress flex-grow-1" style="width: 150px; height: 6px;">
                        <div class="progress-bar" id="topic_progress_bar" role="progressbar" style="width: 0%"></div>
                    </div>
                    <small id="topic_progress" class="text-muted">1/10</small>
                </div>
                <button type="button" class="btn-close btn-close-white" data-bs-dismiss="modal"></button>
            </div>
            <div class="modal-body">
                <!-- Question Display -->
                <div class="mb-3 p-3 bg-black bg-opacity-25 rounded border border-secondary" style="max-height: 180px; overflow-y: auto;">
                    <div id="topic_q_text" class="text-white"></div>
                </div>

                <!-- Subject Selection (Auto-detected, editable) -->
                <div class="mb-3">
                    <label class="form-label small text-muted mb-2">Subject (click to change)</label>
                    <div id="subject_pills" class="d-flex flex-wrap gap-2">
                        <button type="button" class="btn btn-outline-success subject-pill" data-subject="Biology">
                            <i class="bi bi-flower1 me-1"></i>Biology
                        </button>
                        <button type="button" class="btn btn-outline-warning subject-pill" data-subject="Chemistry">
                            <i class="bi bi-droplet me-1"></i>Chemistry
                        </button>
                        <button type="button" class="btn btn-outline-info subject-pill" data-subject="Physics">
                            <i class="bi bi-lightning me-1"></i>Physics
                        </button>
                        <button type="button" class="btn btn-outline-danger subject-pill" data-subject="Mathematics">
                            <i class="bi bi-calculator me-1"></i>Mathematics
                        </button>
                    </div>
                </div>

                <!-- Chapter/Topic Input -->
                <div class="mb-2">
                    <label class="form-label small text-muted mb-2">Chapter / Topic</label>
                    <div class="input-group input-group-lg">
                        <input type="text" id="topic_input" class="form-control bg-dark text-white border-secondary" placeholder="Start typing or use AI...">
                        <button class="btn btn-info" type="button" id="btn_get_suggestion" onclick="getAiSuggestion()">
                            <span class="spinner-border spinner-border-sm d-none" role="status"></span>
                            <i class="bi bi-stars"></i>
                        </button>
                    </div>
                </div>

                <!-- Suggestions -->
                <div id="ai_suggestion_container" class="d-none">
                    <div id="ai_suggestion_chips" class="d-flex flex-wrap gap-2"></div>
                </div>
                <div id="ai_error_msg" class="alert alert-danger d-none mt-2 py-2"></div>
            </div>
            <div class="modal-footer border-secondary py-2">
                <button type="button" class="btn btn-outline-secondary btn-lg px-4" onclick="prevTopicQuestion()">
                    <i class="bi bi-chevron-left"></i>
                </button>
                <button type="button" class="btn btn-primary btn-lg px-5" onclick="nextTopicQuestion()">
                    Next <i class="bi bi-chevron-right ms-1"></i>
                </button>
            </div>
        </div>
    </div>
</div>
            </div>
        </div>
    </div>
</div>
{% endblock %}

{% block scripts %}
<script>
// --- Manual Classification Logic (global functions) ---
let manualQuestionsList = [];
let currentManualIndex = 0;
let manualSubject = "Biology";  // Will be auto-detected
let suggestionCache = new Map();
let selectedRangeMode = 'all'; // 'all', 'unclassified', 'custom'
let customRanges = []; // Array of {start, end, subject} for custom slider ranges
let questionSubjectMap = new Map(); // Maps question index to pre-selected subject

// Get question text preview by visible index
function getQuestionPreview(visibleIndex) {
    const visibleRows = getVisibleRows();
    if (visibleIndex >= 0 && visibleIndex < visibleRows.length) {
        const row = visibleRows[visibleIndex];
        return row.querySelector('.question-text-cell').textContent.substring(0, 80) + '...';
    }
    return '';
}

// Get question number by visible index
function getQuestionNumber(visibleIndex) {
    const visibleRows = getVisibleRows();
    if (visibleIndex >= 0 && visibleIndex < visibleRows.length) {
        return visibleRows[visibleIndex].dataset.index;
    }
    return visibleIndex + 1;
}

// Add a new range slider
function addRangeSlider() {
    const container = document.getElementById('range-sliders-container');
    const visibleRows = getVisibleRows();
    const maxVal = visibleRows.length;

    if (maxVal === 0) {
        alert("No visible questions to select from.");
        return;
    }

    const sliderId = Date.now();

    const sliderHtml = `
        <div class="range-slider-row" id="slider-row-${sliderId}" data-slider-id="${sliderId}">
            <div class="d-flex justify-content-between align-items-center mb-2">
                <div class="d-flex align-items-center gap-2">
                    <span class="badge bg-success" id="start-badge-${sliderId}">Q1</span>
                    <i class="bi bi-arrow-right text-muted"></i>
                    <span class="badge bg-danger" id="end-badge-${sliderId}">Q${maxVal}</span>
                </div>
                <div class="d-flex align-items-center gap-2">
                    <select class="form-select form-select-sm bg-dark text-white border-secondary" id="subject-${sliderId}" style="width: auto;">
                        <option value="auto">🤖 Auto-detect</option>
                        <option value="Biology">🌱 Biology</option>
                        <option value="Chemistry">🧪 Chemistry</option>
                        <option value="Physics">⚡ Physics</option>
                        <option value="Mathematics">📐 Mathematics</option>
                    </select>
                    <button type="button" class="btn btn-sm btn-outline-danger" onclick="removeRangeSlider(${sliderId})">
                        <i class="bi bi-trash"></i>
                    </button>
                </div>
            </div>
            <div class="dual-range-container">
                <div class="dual-range-track"></div>
                <div class="dual-range-highlight" id="highlight-${sliderId}"></div>
                <input type="range" min="1" max="${maxVal}" value="1" class="range-start" id="start-${sliderId}"
                       oninput="updateRangeSlider(${sliderId})">
                <input type="range" min="1" max="${maxVal}" value="${maxVal}" class="range-end" id="end-${sliderId}"
                       oninput="updateRangeSlider(${sliderId})">
            </div>
        </div>
    `;

    container.insertAdjacentHTML('beforeend', sliderHtml);
    customRanges.push({ id: sliderId, start: 1, end: maxVal, subject: 'auto' });

    // Add subject change listener
    document.getElementById(`subject-${sliderId}`).addEventListener('change', (e) => {
        const rangeObj = customRanges.find(r => r.id === sliderId);
        if (rangeObj) rangeObj.subject = e.target.value;
    });

    updateRangeSlider(sliderId);
    updateSelectedRangesDisplay();
    updateRangePreview();
}

// Update range slider visuals and values
function updateRangeSlider(sliderId) {
    const startInput = document.getElementById(`start-${sliderId}`);
    const endInput = document.getElementById(`end-${sliderId}`);
    const highlight = document.getElementById(`highlight-${sliderId}`);
    const startBadge = document.getElementById(`start-badge-${sliderId}`);
    const endBadge = document.getElementById(`end-badge-${sliderId}`);

    let startVal = parseInt(startInput.value);
    let endVal = parseInt(endInput.value);

    // Ensure start <= end
    if (startVal > endVal) {
        if (startInput === document.activeElement) {
            endInput.value = startVal;
            endVal = startVal;
        } else {
            startInput.value = endVal;
            startVal = endVal;
        }
    }

    // Update highlight bar
    const max = parseInt(startInput.max);
    const leftPercent = ((startVal - 1) / (max - 1)) * 100;
    const rightPercent = ((endVal - 1) / (max - 1)) * 100;
    highlight.style.left = leftPercent + '%';
    highlight.style.width = (rightPercent - leftPercent) + '%';

    // Update badges with actual question numbers
    startBadge.textContent = `#${getQuestionNumber(startVal - 1)}`;
    endBadge.textContent = `#${getQuestionNumber(endVal - 1)}`;

    // Update stored range
    const rangeObj = customRanges.find(r => r.id === sliderId);
    if (rangeObj) {
        rangeObj.start = startVal;
        rangeObj.end = endVal;
    }

    updateSelectedRangesDisplay();
    updateRangePreview();
}

// Remove a range slider
function removeRangeSlider(sliderId) {
    document.getElementById(`slider-row-${sliderId}`)?.remove();
    customRanges = customRanges.filter(r => r.id !== sliderId);
    updateSelectedRangesDisplay();
    updateRangePreview();
}

// Update the display of selected ranges
function updateSelectedRangesDisplay() {
    const display = document.getElementById('selected-ranges-display');
    const countSpan = document.getElementById('selected-count');

    if (customRanges.length === 0) {
        display.textContent = 'None';
        countSpan.textContent = '0';
        return;
    }

    const rangeStrs = customRanges.map(r => {
        const startNum = getQuestionNumber(r.start - 1);
        const endNum = getQuestionNumber(r.end - 1);
        return r.start === r.end ? `#${startNum}` : `#${startNum}-#${endNum}`;
    });
    display.textContent = rangeStrs.join(', ');

    // Count unique questions
    const indices = new Set();
    customRanges.forEach(r => {
        for (let i = r.start; i <= r.end; i++) indices.add(i);
    });
    countSpan.textContent = indices.size;
}

// Update preview text
function updateRangePreview() {
    if (customRanges.length === 0) return;

    // Find first and last question across all ranges
    let minQ = Infinity, maxQ = -Infinity;
    customRanges.forEach(r => {
        if (r.start < minQ) minQ = r.start;
        if (r.end > maxQ) maxQ = r.end;
    });

    const startIdx = minQ - 1;
    const endIdx = maxQ - 1;

    document.getElementById('preview-start-text').textContent = getQuestionPreview(startIdx);
    document.getElementById('preview-end-text').textContent = getQuestionPreview(endIdx);
    document.getElementById('preview-start-num').textContent = `#${getQuestionNumber(startIdx)}`;
    document.getElementById('preview-end-num').textContent = `#${getQuestionNumber(endIdx)}`;
}

// Setup range toggle handlers
function setupRangeToggles() {
    document.querySelectorAll('.range-toggle').forEach(btn => {
        btn.addEventListener('click', () => {
            document.querySelectorAll('.range-toggle').forEach(b => b.classList.remove('active'));
            btn.classList.add('active');
            selectedRangeMode = btn.dataset.range;

            // Show/hide custom range container
            const customContainer = document.getElementById('custom-range-container');
            if (selectedRangeMode === 'custom') {
                customContainer.classList.remove('d-none');
                // Add initial slider if none exist
                if (customRanges.length === 0) {
                    addRangeSlider();
                }
            } else {
                customContainer.classList.add('d-none');
            }
        });
    });
}

// Subject detection keywords
const SUBJECT_KEYWORDS = {
    'Biology': ['cell', 'dna', 'rna', 'protein', 'enzyme', 'mitosis', 'meiosis', 'photosynthesis', 'respiration', 'chromosome', 'gene', 'mutation', 'evolution', 'species', 'organism', 'tissue', 'organ', 'plant', 'animal', 'bacteria', 'virus', 'ecology', 'ecosystem', 'biodiversity', 'reproduction', 'hormone', 'neuron', 'blood', 'heart', 'kidney', 'liver', 'digestion', 'excretion', 'inheritance', 'mendel', 'allele', 'genotype', 'phenotype', 'biomolecule', 'lipid', 'carbohydrate', 'amino acid'],
    'Chemistry': ['atom', 'molecule', 'electron', 'proton', 'neutron', 'orbital', 'bond', 'ionic', 'covalent', 'reaction', 'oxidation', 'reduction', 'acid', 'base', 'ph', 'salt', 'equilibrium', 'mole', 'molarity', 'concentration', 'solution', 'organic', 'inorganic', 'alkane', 'alkene', 'alkyne', 'alcohol', 'aldehyde', 'ketone', 'ester', 'ether', 'amine', 'polymer', 'thermodynamics', 'enthalpy', 'entropy', 'electrochemistry', 'electrolysis', 'catalyst', 'kinetics', 'periodic table', 'element', 'compound'],
    'Physics': ['force', 'velocity', 'acceleration', 'momentum', 'energy', 'work', 'power', 'newton', 'gravity', 'friction', 'motion', 'wave', 'frequency', 'wavelength', 'amplitude', 'sound', 'light', 'optics', 'lens', 'mirror', 'reflection', 'refraction', 'diffraction', 'interference', 'electric', 'current', 'voltage', 'resistance', 'capacitor', 'inductor', 'magnetic', 'electromagnetic', 'quantum', 'photon', 'nuclear', 'radioactive', 'thermodynamics', 'heat', 'temperature', 'pressure'],
    'Mathematics': ['equation', 'function', 'derivative', 'integral', 'limit', 'matrix', 'determinant', 'vector', 'probability', 'statistics', 'mean', 'median', 'variance', 'trigonometry', 'sine', 'cosine', 'tangent', 'logarithm', 'exponential', 'polynomial', 'quadratic', 'linear', 'geometry', 'circle', 'triangle', 'parabola', 'ellipse', 'hyperbola', 'calculus', 'differentiation', 'integration', 'sequence', 'series', 'permutation', 'combination', 'set', 'relation', 'complex number']
};

// All NCERT chapters by subject for autocomplete
const ALL_CHAPTERS = {
    'Biology': [
        'The Living World', 'Biological Classification', 'Plant Kingdom', 'Animal Kingdom',
        'Morphology of Flowering Plants', 'Anatomy of Flowering Plants', 'Structural Organisation in Animals',
        'Cell: The Unit of Life', 'Biomolecules', 'Cell Cycle and Cell Division',
        'Photosynthesis in Higher Plants', 'Respiration in Plants', 'Plant Growth and Development',
        'Breathing and Exchange of Gases', 'Body Fluids and Circulation', 'Excretory Products and their Elimination',
        'Locomotion and Movement', 'Neural Control and Coordination', 'Chemical Coordination and Integration',
        'Sexual Reproduction in Flowering Plants', 'Human Reproduction', 'Reproductive Health',
        'Principles of Inheritance and Variation', 'Molecular Basis of Inheritance', 'Evolution',
        'Health and Disease', 'Improvement in Food Production', 'Microbes in Human Welfare',
        'Biotechnology - Principles and Processes', 'Biotechnology and Its Applications',
        'Organisms and Populations', 'Ecosystem', 'Biodiversity and Its Conservation'
    ],
    'Chemistry': [
        'Some Basic Concepts of Chemistry', 'Structure of Atom', 'Classification of Elements and Periodicity in Properties',
        'Chemical Bonding and Molecular Structure', 'States of Matter: Gases and Liquids', 'Thermodynamics',
        'Equilibrium', 'Redox Reactions', 'Hydrogen', 'The s-Block Elements', 'The p-Block Elements (Group 13 and 14)',
        'Organic Chemistry – Some Basic Principles and Techniques (GOC)', 'Hydrocarbons', 'Environmental Chemistry',
        'The Solid State', 'Solutions', 'Electrochemistry', 'Chemical Kinetics', 'Surface Chemistry',
        'General Principles and Processes of Isolation of Elements (Metallurgy)', 'The p-Block Elements (Group 15 to 18)',
        'The d- and f- Block Elements', 'Coordination Compounds', 'Haloalkanes and Haloarenes',
        'Alcohols, Phenols and Ethers', 'Aldehydes, Ketones and Carboxylic Acids', 'Amines',
        'Biomolecules', 'Polymers', 'Chemistry in Everyday Life'
    ],
    'Physics': [
        'Units and Measurements', 'Motion in a Straight Line', 'Motion in a Plane', 'Laws of Motion',
        'Work, Energy and Power', 'System of Particles and Rotational Motion', 'Gravitation',
        'Mechanical Properties of Solids', 'Mechanical Properties of Fluids', 'Thermal Properties of Matter',
        'Thermodynamics', 'Kinetic Theory', 'Oscillations', 'Waves',
        'Electric Charges and Fields', 'Electrostatic Potential and Capacitance', 'Current Electricity',
        'Moving Charges and Magnetism', 'Magnetism and Matter', 'Electromagnetic Induction',
        'Alternating Current', 'Electromagnetic Waves', 'Ray Optics and Optical Instruments',
        'Wave Optics', 'Dual Nature of Radiation and Matter', 'Atoms', 'Nuclei',
        'Semiconductor Electronics: Materials, Devices and Simple Circuits', 'Communication Systems'
    ],
    'Mathematics': [
        'Sets', 'Relations and Functions', 'Trigonometric Functions', 'Principle of Mathematical Induction',
        'Complex Numbers and Quadratic Equations', 'Linear Inequalities', 'Permutations and Combinations',
        'Binomial Theorem', 'Sequences and Series', 'Straight Lines', 'Conic Sections',
        'Introduction to Three Dimensional Geometry', 'Limits and Derivatives', 'Mathematical Reasoning',
        'Statistics', 'Probability', 'Inverse Trigonometric Functions', 'Matrices', 'Determinants',
        'Continuity and Differentiability', 'Application of Derivatives', 'Integrals',
        'Application of Integrals', 'Differential Equations', 'Vector Algebra',
        'Three Dimensional Geometry', 'Linear Programming'
    ]
};

function detectSubject(text) {
    const lowerText = text.toLowerCase();
    const scores = {};

    for (const [subject, keywords] of Object.entries(SUBJECT_KEYWORDS)) {
        scores[subject] = 0;
        for (const keyword of keywords) {
            if (lowerText.includes(keyword)) {
                scores[subject]++;
            }
        }
    }

    // Sort by score and return top subjects
    const sorted = Object.entries(scores).sort((a, b) => b[1] - a[1]);
    const topSubjects = sorted.filter(([_, score]) => score > 0).slice(0, 2).map(([subj, _]) => subj);

    return topSubjects.length > 0 ? topSubjects : ['Biology'];  // Default to Biology
}

function setActiveSubject(subject) {
    manualSubject = subject;
    document.querySelectorAll('.subject-pill').forEach(pill => {
        if (pill.dataset.subject === subject) {
            pill.classList.remove('btn-outline-success', 'btn-outline-warning', 'btn-outline-info', 'btn-outline-danger');
            pill.classList.add('btn-success', 'btn-warning', 'btn-info', 'btn-danger');
            // Keep the appropriate color
            if (subject === 'Biology') { pill.className = 'btn btn-success subject-pill'; }
            else if (subject === 'Chemistry') { pill.className = 'btn btn-warning subject-pill'; }
            else if (subject === 'Physics') { pill.className = 'btn btn-info subject-pill'; }
            else if (subject === 'Mathematics') { pill.className = 'btn btn-danger subject-pill'; }
        } else {
            // Reset to outline
            if (pill.dataset.subject === 'Biology') { pill.className = 'btn btn-outline-success subject-pill'; }
            else if (pill.dataset.subject === 'Chemistry') { pill.className = 'btn btn-outline-warning subject-pill'; }
            else if (pill.dataset.subject === 'Physics') { pill.className = 'btn btn-outline-info subject-pill'; }
            else if (pill.dataset.subject === 'Mathematics') { pill.className = 'btn btn-outline-danger subject-pill'; }
        }
    });
}

function getVisibleRows() {
    // Get only currently visible (filtered) rows
    return Array.from(document.querySelectorAll('#questions-table-body tr')).filter(row => row.style.display !== 'none');
}

function updateTypingSuggestions(inputValue) {
    const container = document.getElementById('ai_suggestion_container');
    const chipsContainer = document.getElementById('ai_suggestion_chips');

    if (!inputValue || inputValue.length < 2) {
        return;
    }

    const chapters = ALL_CHAPTERS[manualSubject] || [];
    const searchLower = inputValue.toLowerCase();

    // Filter chapters that match the input
    const matches = chapters.filter(ch => ch.toLowerCase().includes(searchLower)).slice(0, 6);

    if (matches.length > 0) {
        container.classList.remove('d-none');
        chipsContainer.innerHTML = '';

        matches.forEach(suggestion => {
            const chip = document.createElement('button');
            chip.className = 'btn btn-outline-secondary btn-sm rounded-pill';
            chip.innerText = suggestion;
            chip.onclick = () => {
                document.getElementById('topic_input').value = suggestion;
                chipsContainer.innerHTML = '';
                container.classList.add('d-none');
            };
            chipsContainer.appendChild(chip);
        });
    }
}

document.addEventListener('DOMContentLoaded', function () {
    const editModal = new bootstrap.Modal(document.getElementById('editModal'));
    const editQuestionId = document.getElementById('edit-question-id');
    const editTopic = document.getElementById('edit-topic');
    const editSubject = document.getElementById('edit-subject');

    document.querySelectorAll('.edit-btn').forEach(button => {
        button.addEventListener('click', () => {
            editQuestionId.value = button.dataset.id;
            editTopic.value = button.dataset.topic;
            editSubject.value = button.dataset.subject;
        });
    });

    document.getElementById('save-changes-btn').addEventListener('click', async () => {
        const id = editQuestionId.value;
        const topic = editTopic.value;
        const subject = editSubject.value;

        try {
            const response = await fetch(`/neetprep/update_question/${id}`, {
                method: 'POST',
                headers: { 'Content-Type': 'application/json' },
                body: JSON.stringify({ topic: topic, subject: subject })
            });
            const result = await response.json();

            if (result.success) {
                const row = document.querySelector(`button[data-id='${id}']`).closest('tr');
                row.querySelector('.topic-cell').textContent = topic;
                row.querySelector('.subject-cell').textContent = subject;
                const editBtn = row.querySelector('.edit-btn');
                editBtn.dataset.topic = topic;
                editBtn.dataset.subject = subject;
                editModal.hide();
            } else {
                alert(`Error: ${result.error}`);
            }
        } catch (error) {
            alert(`Request failed: ${error}`);
        }
    });

    // --- Filtering Logic ---
    const searchInput = document.getElementById('search-input');
    const topicFilter = document.getElementById('topic-filter');
    const tableBody = document.getElementById('questions-table-body');
    const rows = tableBody.getElementsByTagName('tr');

    function filterTable() {
        const searchText = searchInput.value.toLowerCase();
        const selectedTopic = topicFilter.value;

        for (let i = 0; i < rows.length; i++) {
            const row = rows[i];
            const topic = row.dataset.topic;
            const text = row.textContent || row.innerText;

            const topicMatch = (selectedTopic === 'all' || topic === selectedTopic);
            const searchMatch = (text.toLowerCase().indexOf(searchText) > -1);

            if (topicMatch && searchMatch) {
                row.style.display = "";
            } else {
                row.style.display = "none";
            }
        }
    }

    searchInput.addEventListener('keyup', filterTable);
    topicFilter.addEventListener('change', filterTable);

    // Apply filter on page load (default to Unclassified)
    filterTable();

    // Update visible count when modal opens
    document.getElementById('manualClassificationModal').addEventListener('show.bs.modal', () => {
        const visibleCount = getVisibleRows().length;
        document.getElementById('visible-count-info').textContent =
            `${visibleCount} questions currently visible. Classification will apply to these.`;
        // Reset slider state when modal opens
        customRanges = [];
        document.getElementById('range-sliders-container').innerHTML = '';
        document.getElementById('custom-range-container').classList.add('d-none');
        document.querySelectorAll('.range-toggle').forEach(b => b.classList.toggle('active', b.dataset.range === 'all'));
        selectedRangeMode = 'all';
    });

    // Setup range toggles
    setupRangeToggles();

    // Live autocomplete as user types in topic input
    document.getElementById('topic_input').addEventListener('input', (e) => {
        updateTypingSuggestions(e.target.value);
    });
});

function parseRange(rangeStr, maxVal) {
    const indices = new Set();
    const parts = rangeStr.split(',');
    for (let part of parts) {
        part = part.trim();
        if (!part) continue;
        if (part.includes('-')) {
            const [start, end] = part.split('-').map(Number);
            if (!isNaN(start) && !isNaN(end)) {
                for (let i = start; i <= end; i++) indices.add(i);
            }
        } else {
            const num = Number(part);
            if (!isNaN(num)) indices.add(num);
        }
    }
    return Array.from(indices).filter(i => i >= 1 && i <= maxVal).sort((a, b) => a - b);
}

function startManualClassification() {
    // Get only visible (filtered) rows
    const visibleRows = getVisibleRows();
    const numQuestions = visibleRows.length;

    if (numQuestions === 0) {
        alert("No questions visible. Please adjust your filter.");
        return;
    }

    // Build list based on selected mode
    questionSubjectMap.clear();
    if (selectedRangeMode === 'custom') {
        // Use custom slider ranges with their subject settings
        if (customRanges.length === 0) {
            alert("Please add at least one range.");
            return;
        }
        const visibleIndices = visibleRows.map((row, idx) => ({ idx, qIndex: parseInt(row.dataset.index) }));
        const selectedIndices = new Set();
        customRanges.forEach(r => {
            for (let i = r.start; i <= r.end; i++) {
                if (i <= visibleIndices.length) {
                    const qIndex = visibleIndices[i - 1].qIndex;
                    selectedIndices.add(qIndex);
                    // Store subject for this question (if not auto)
                    if (r.subject && r.subject !== 'auto') {
                        questionSubjectMap.set(qIndex, r.subject);
                    }
                }
            }
        });
        manualQuestionsList = Array.from(selectedIndices).sort((a, b) => a - b);
    } else if (selectedRangeMode === 'unclassified') {
        // Only unclassified from visible
        manualQuestionsList = visibleRows
            .filter(row => {
                const topic = row.querySelector('.topic-cell').textContent;
                return !topic || topic === 'Unclassified';
            })
            .map(row => parseInt(row.dataset.index));
    } else {
        // All visible questions
        manualQuestionsList = visibleRows.map(row => parseInt(row.dataset.index));
    }

    if (manualQuestionsList.length === 0) {
        alert("No questions match the selected criteria.");
        return;
    }

    currentManualIndex = 0;
    suggestionCache.clear();

    const modal1 = bootstrap.Modal.getInstance(document.getElementById('manualClassificationModal'));
    modal1.hide();

    const modal2 = new bootstrap.Modal(document.getElementById('topicSelectionModal'));
    modal2.show();

    // Setup subject pill click handlers
    document.querySelectorAll('.subject-pill').forEach(pill => {
        pill.onclick = () => {
            setActiveSubject(pill.dataset.subject);
            // Clear suggestions and show loading when subject changes
            const container = document.getElementById('ai_suggestion_container');
            const chipsContainer = document.getElementById('ai_suggestion_chips');
            container.classList.remove('d-none');
            chipsContainer.innerHTML = '<span class="text-muted"><i class="bi bi-hourglass-split me-1"></i>Loading...</span>';
            document.getElementById('topic_input').value = '';
            // Clear cache for current question and refetch
            const qIndex = manualQuestionsList[currentManualIndex];
            const row = document.querySelector(`#questions-table-body tr[data-index="${qIndex}"]`);
            if (row) {
                suggestionCache.delete(row.dataset.id);
                getAiSuggestion();
            }
        };
    });

    loadTopicQuestion();

    // Prefetch suggestions for up to 30 questions in background
    prefetchSuggestions(0, 30);
}

function prefetchSuggestions(startIndex, count) {
    // Group questions by their pre-selected subject for batch processing
    const subjectBatches = new Map(); // subject -> [{qIndex, questionId}]
    const autoDetectQueue = []; // Questions without pre-selected subject

    for (let i = startIndex; i < startIndex + count && i < manualQuestionsList.length; i++) {
        const qIndex = manualQuestionsList[i];
        const row = document.querySelector(`#questions-table-body tr[data-index="${qIndex}"]`);
        if (!row) continue;
        const questionId = row.dataset.id;

        if (suggestionCache.has(questionId)) continue;

        const preSelectedSubject = questionSubjectMap.get(qIndex);
        if (preSelectedSubject) {
            // Group by subject for batch processing
            if (!subjectBatches.has(preSelectedSubject)) {
                subjectBatches.set(preSelectedSubject, []);
            }
            subjectBatches.get(preSelectedSubject).push({ qIndex, questionId });
        } else {
            // Auto-detect: process individually
            autoDetectQueue.push({ qIndex, questionId });
        }
    }

    // Process batched requests (up to 8 per subject per batch)
    for (const [subject, questions] of subjectBatches) {
        for (let i = 0; i < questions.length; i += 8) {
            const batch = questions.slice(i, i + 8);
            const questionIds = batch.map(q => q.questionId);

            // Create a single promise for the batch
            const batchPromise = fetch('/neetprep/get_suggestions_batch', {
                method: 'POST',
                headers: { 'Content-Type': 'application/json' },
                body: JSON.stringify({ question_ids: questionIds, subject: subject })
            })
            .then(res => res.json())
            .then(data => {
                if (data.success && data.results) {
                    return data.results; // Map of questionId -> result
                }
                throw new Error(data.error || 'Batch request failed');
            })
            .catch(err => {
                // Return fallback for all questions in batch
                const fallback = {};
                questionIds.forEach(id => {
                    fallback[id] = { status: 'error', suggestions: ['Unclassified'], subject: subject, error: err.message };
                });
                return fallback;
            });

            // Store promise for each question that resolves to its specific result
            batch.forEach(q => {
                suggestionCache.set(q.questionId, batchPromise.then(results => {
                    const result = results[q.questionId];
                    if (result) {
                        return {
                            status: 'done',
                            suggestions: result.suggestions || ['Unclassified'],
                            subject: result.subject || subject,
                            otherSubjects: result.other_possible_subjects || []
                        };
                    }
                    return { status: 'done', suggestions: ['Unclassified'], subject: subject, otherSubjects: [] };
                }));
            });
        }
    }

    // Process auto-detect questions individually
    for (const q of autoDetectQueue) {
        const promise = fetch(`/neetprep/get_suggestions/${q.questionId}`, {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify({})
        })
        .then(res => res.json())
        .then(data => {
            if (data.success) {
                return {
                    status: 'done',
                    suggestions: data.suggestions || ['Unclassified'],
                    subject: data.subject,
                    otherSubjects: data.other_possible_subjects || []
                };
            }
            return { status: 'done', suggestions: ['Unclassified'], subject: 'Biology' };
        })
        .catch(err => ({ status: 'error', suggestions: ['Unclassified'], subject: 'Biology', error: err.message }));

        suggestionCache.set(q.questionId, promise);
    }
}

function loadTopicQuestion() {
    const qIndex = manualQuestionsList[currentManualIndex];
    const row = document.querySelector(`#questions-table-body tr[data-index="${qIndex}"]`);
    if (!row) return;

    const questionId = row.dataset.id;
    const questionHtml = row.dataset.html || row.querySelector('.question-text-cell').textContent;
    const questionPlainText = row.querySelector('.question-text-cell').textContent;
    const currentTopic = row.querySelector('.topic-cell').textContent;
    const currentSubjectFromRow = row.querySelector('.subject-cell').textContent;

    // Check if subject was pre-selected in slider, otherwise auto-detect
    const preSelectedSubject = questionSubjectMap.get(qIndex);
    if (preSelectedSubject) {
        manualSubject = preSelectedSubject;
    } else if (currentSubjectFromRow && currentSubjectFromRow !== 'Unclassified' && ALL_CHAPTERS[currentSubjectFromRow]) {
        manualSubject = currentSubjectFromRow;
    } else {
        const detectedSubjects = detectSubject(questionPlainText);
        manualSubject = detectedSubjects[0];
    }
    setActiveSubject(manualSubject);

    // Update UI
    document.getElementById('topic_q_num').innerText = `#${qIndex}`;
    document.getElementById('topic_q_text').innerHTML = questionHtml;  // Render HTML
    document.getElementById('topic_input').value = (currentTopic && currentTopic !== 'Unclassified') ? currentTopic : '';
    document.getElementById('topic_progress').innerText = `${currentManualIndex + 1}/${manualQuestionsList.length}`;

    // Update progress bar
    const progressPercent = ((currentManualIndex + 1) / manualQuestionsList.length) * 100;
    document.getElementById('topic_progress_bar').style.width = `${progressPercent}%`;

    // Clear previous suggestions
    document.getElementById('ai_suggestion_container').classList.add('d-none');
    document.getElementById('ai_suggestion_chips').innerHTML = '';
    document.getElementById('ai_error_msg').classList.add('d-none');

    // Reset button
    const btn = document.getElementById('btn_get_suggestion');
    btn.disabled = false;
    btn.querySelector('.spinner-border').classList.add('d-none');

    // Auto-get suggestions if topic is empty
    if (!document.getElementById('topic_input').value) {
        getAiSuggestion();
    }
}

async function nextTopicQuestion() {
    // Save in background (don't await - non-blocking)
    saveCurrentTopic();

    if (currentManualIndex < manualQuestionsList.length - 1) {
        currentManualIndex++;
        loadTopicQuestion();
        // Prefetch more suggestions as we progress (sliding window of 30)
        prefetchSuggestions(currentManualIndex + 1, 30);
    } else {
        const modal2 = bootstrap.Modal.getInstance(document.getElementById('topicSelectionModal'));
        modal2.hide();
        alert("Manual classification completed!");
        // Refresh the filter to show updated results
        document.getElementById('topic-filter').dispatchEvent(new Event('change'));
    }
}

function prevTopicQuestion() {
    if (currentManualIndex > 0) {
        currentManualIndex--;
        loadTopicQuestion();
    }
}

function saveCurrentTopic() {
    const qIndex = manualQuestionsList[currentManualIndex];
    const row = document.querySelector(`#questions-table-body tr[data-index="${qIndex}"]`);
    if (!row) return;

    const questionId = row.dataset.id;
    const topic = document.getElementById('topic_input').value || 'Unclassified';

    // Update UI immediately
    row.querySelector('.topic-cell').textContent = topic;
    row.querySelector('.subject-cell').textContent = manualSubject;
    row.dataset.topic = topic;  // Update data attribute for filtering
    const editBtn = row.querySelector('.edit-btn');
    if (editBtn) {
        editBtn.dataset.topic = topic;
        editBtn.dataset.subject = manualSubject;
    }

    // Save to backend in background (fire and forget)
    fetch(`/neetprep/update_question/${questionId}`, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ topic: topic, subject: manualSubject })
    }).catch(e => console.error("Failed to save topic", e));
}

async function getAiSuggestion() {
    const qIndex = manualQuestionsList[currentManualIndex];
    const row = document.querySelector(`#questions-table-body tr[data-index="${qIndex}"]`);
    if (!row) return;

    const questionId = row.dataset.id;
    const btn = document.getElementById('btn_get_suggestion');
    const container = document.getElementById('ai_suggestion_container');
    const chipsContainer = document.getElementById('ai_suggestion_chips');
    const errorDiv = document.getElementById('ai_error_msg');

    btn.disabled = true;
    btn.querySelector('.spinner-border').classList.remove('d-none');
    errorDiv.classList.add('d-none');

    try {
        let result;
        if (suggestionCache.has(questionId)) {
            result = await suggestionCache.get(questionId);
        } else {
            // Check if subject was pre-selected in slider
            const preSelectedSubject = questionSubjectMap.get(qIndex);
            const requestBody = preSelectedSubject
                ? { subject: preSelectedSubject }
                : {};  // No subject - AI will detect

            const promise = fetch(`/neetprep/get_suggestions/${questionId}`, {
                method: 'POST',
                headers: { 'Content-Type': 'application/json' },
                body: JSON.stringify(requestBody)
            })
            .then(res => res.json())
            .then(data => ({
                status: 'done',
                suggestions: data.suggestions || ['Unclassified'],
                subject: data.subject,
                otherSubjects: data.other_possible_subjects || []
            }))
            .catch(err => ({ status: 'error', suggestions: ['Unclassified'], subject: 'Biology', error: err.message }));

            suggestionCache.set(questionId, promise);
            result = await promise;
        }

        // Update subject from AI response
        if (result.subject) {
            setActiveSubject(result.subject);
        }

        container.classList.remove('d-none');
        chipsContainer.innerHTML = '';

        // Add a label for AI suggestions
        const label = document.createElement('span');
        label.className = 'badge bg-info me-2';
        label.innerText = 'AI';
        chipsContainer.appendChild(label);

        // Show other possible subjects if detected
        if (result.otherSubjects && result.otherSubjects.length > 0) {
            const otherLabel = document.createElement('span');
            otherLabel.className = 'badge bg-secondary me-2';
            otherLabel.innerText = `Also: ${result.otherSubjects.join(', ')}`;
            otherLabel.title = 'This question may also belong to these subjects';
            chipsContainer.appendChild(otherLabel);
        }

        result.suggestions.forEach(suggestion => {
            const chip = document.createElement('button');
            chip.className = 'btn btn-outline-info btn-sm rounded-pill';
            chip.innerText = suggestion;
            chip.onclick = () => {
                document.getElementById('topic_input').value = suggestion;
            };
            chipsContainer.appendChild(chip);
        });

        // Auto-fill if empty
        const currentVal = document.getElementById('topic_input').value;
        if (!currentVal && result.suggestions.length > 0) {
            document.getElementById('topic_input').value = result.suggestions[0];
        }

    } catch (e) {
        errorDiv.innerText = `Error: ${e.message}`;
        errorDiv.classList.remove('d-none');
    } finally {
        btn.disabled = false;
        btn.querySelector('.spinner-border').classList.add('d-none');
    }
}
</script>
{% endblock %}