{% extends "base.html" %}

{% block title %}Upload PDF{% endblock %}

{% block head %}
<!-- Ensure mobile viewport settings are correct -->
<meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no, maximum-scale=1, viewport-fit=cover">
<style>
    :root {
        --app-bg: #181a1c;
        --card-bg: #212529;
        --input-bg: #2c3034;
        --border-color: #495057;
        --primary-color: #0d6efd;
        --touch-target: 48px;
    }

    body {
        background-color: var(--app-bg);
        color: #e9ecef;
    }

    /* Full height container with dynamic viewport support */
    .upload-wrapper {
        min-height: calc(100vh - 56px);
        min-height: calc(100dvh - 56px);
        display: flex;
        align-items: center;
        justify-content: center;
        padding: 1rem;
        padding-bottom: env(safe-area-inset-bottom);
    }

    .main-card {
        background-color: var(--card-bg);
        border: 1px solid var(--border-color);
        border-radius: 16px;
        box-shadow: 0 4px 20px rgba(0,0,0,0.4);
        width: 100%;
        max-width: 600px;
        overflow: hidden;
    }

    /* Custom segmented tabs */
    .nav-pills {
        background: var(--input-bg);
        padding: 4px;
        border-radius: 12px;
        gap: 4px;
    }
    
    .nav-pills .nav-link {
        border-radius: 8px;
        color: #adb5bd !important;
        font-size: 0.9rem;
        padding: 10px;
        transition: all 0.2s;
    }

    .nav-pills .nav-link.active {
        background-color: var(--primary-color) !important;
        color: white !important;
        font-weight: 600;
        box-shadow: 0 2px 6px rgba(0,0,0,0.2);
    }

    /* File Drop Zone Styling */
    .file-drop-area {
        position: relative;
        display: flex;
        align-items: center;
        justify-content: center;
        flex-direction: column;
        width: 100%;
        max-width: 100%;
        padding: 30px;
        border: 2px dashed var(--border-color);
        border-radius: 12px;
        transition: 0.2s;
        background: rgba(255,255,255,0.02);
        cursor: pointer;
    }

    .file-drop-area:hover, .file-drop-area.drag-over {
        border-color: var(--primary-color);
        background: rgba(13, 110, 253, 0.05);
    }

    .fake-btn {
        background: var(--input-bg);
        border: 1px solid var(--border-color);
        border-radius: 8px;
        padding: 8px 16px;
        font-size: 0.9rem;
        margin-top: 10px;
    }

    .file-msg {
        font-size: 0.95rem;
        font-weight: 500;
        color: #dee2e6;
        text-align: center;
    }

    .file-input {
        position: absolute;
        left: 0;
        top: 0;
        height: 100%;
        width: 100%;
        opacity: 0;
        cursor: pointer;
    }

    /* Large touch-friendly inputs */
    .form-control-lg {
        background-color: var(--input-bg);
        border-color: var(--border-color);
        color: white;
        font-size: 16px; /* Prevents iOS zoom */
        min-height: var(--touch-target);
    }
    
    .form-control-lg:focus {
        background-color: var(--input-bg);
        border-color: var(--primary-color);
        color: white;
        box-shadow: 0 0 0 3px rgba(13, 110, 253, 0.25);
    }

    /* Main Action Button */
    .btn-action {
        min-height: 54px;
        font-size: 1.1rem;
        font-weight: 600;
        border-radius: 12px;
        display: flex;
        align-items: center;
        justify-content: center;
        gap: 10px;
        transition: transform 0.1s;
    }
    
    .btn-action:active {
        transform: scale(0.98);
    }

    /* List items for existing PDFs */
    .list-group-item {
        padding: 16px;
        min-height: 54px; /* Touch target size */
        border-color: var(--border-color);
        display: flex;
        align-items: center;
        justify-content: space-between;
    }
    
    .list-group-item:active {
        background-color: rgba(255,255,255,0.1) !important;
    }

    /* Animations */
    .fade-in-up {
        animation: fadeInUp 0.4s ease-out forwards;
    }
    
    @keyframes fadeInUp {
        from { opacity: 0; transform: translateY(10px); }
        to { opacity: 1; transform: translateY(0); }
    }
</style>
{% endblock %}

{% block content %}
<div class="upload-wrapper">
    <div class="main-card fade-in-up">
        
        <!-- Header -->
        <div class="p-4 border-bottom border-secondary" style="border-color: #495057 !important;">
            <div class="text-center">
                <div class="bg-primary bg-opacity-10 text-primary d-inline-flex align-items-center justify-content-center rounded-circle mb-3" style="width: 56px; height: 56px;">
                    <i class="bi bi-file-earmark-pdf-fill fs-3"></i>
                </div>
                <h1 class="h4 mb-1">Analyze PDF</h1>
                <p class="text-secondary small mb-0">Upload a document to extract questions</p>
            </div>
        </div>

        <div class="card-body p-4">
            
            <!-- Navigation Tabs -->
            <ul class="nav nav-pills nav-fill mb-4" id="uploadMethodTab" role="tablist">
                <li class="nav-item" role="presentation">
                    <button class="nav-link active" id="file-tab" data-bs-toggle="tab" data-bs-target="#file-upload-pane" type="button" role="tab" aria-controls="file-upload-pane" aria-selected="true">
                        <i class="bi bi-folder2-open me-1"></i> File
                    </button>
                </li>
                <li class="nav-item" role="presentation">
                    <button class="nav-link" id="url-tab" data-bs-toggle="tab" data-bs-target="#url-upload-pane" type="button" role="tab" aria-controls="url-upload-pane" aria-selected="false">
                        <i class="bi bi-link-45deg me-1"></i> URL
                    </button>
                </li>
                <li class="nav-item" role="presentation">
                    <button class="nav-link" id="curl-tab" data-bs-toggle="tab" data-bs-target="#curl-upload-pane" type="button" role="tab" aria-controls="curl-upload-pane" aria-selected="false">
                        <i class="bi bi-code-slash me-1"></i> cURL
                    </button>
                </li>
            </ul>

            <form id="upload-form">
                <div class="tab-content mb-4">
                    
                    <!-- File Upload Pane -->
                    <div class="tab-pane fade show active" id="file-upload-pane" role="tabpanel" aria-labelledby="file-tab">
                        <div class="file-drop-area" id="drop-zone">
                            <span class="file-msg" id="file-label-text">Tap to select or drag PDF here</span>
                            <span class="fake-btn">Choose File</span>
                            <input class="file-input" type="file" id="pdf-upload" name="pdf" accept=".pdf">
                        </div>
                    </div>

                    <!-- URL Pane -->
                    <div class="tab-pane fade" id="url-upload-pane" role="tabpanel" aria-labelledby="url-tab">
                        <div class="mb-3">
                            <label for="pdf-url" class="form-label small text-secondary">PDF URL Address</label>
                            <input type="url" class="form-control form-control-lg" id="pdf-url" name="pdf_url" placeholder="https://example.com/doc.pdf or Google Drive Link" autocomplete="off">
                            <div class="form-text text-muted small mt-1"><i class="bi bi-google"></i> Google Drive sharing links supported</div>
                        </div>
                    </div>

                    <!-- cURL Pane -->
                    <div class="tab-pane fade" id="curl-upload-pane" role="tabpanel" aria-labelledby="curl-tab">
                        <div class="mb-3">
                            <label for="curl-command" class="form-label small text-secondary">Paste cURL Command</label>
                            <textarea class="form-control form-control-lg" id="curl-command" name="curl_command" placeholder="curl -o 'report.pdf' ..." rows="2" style="font-family: monospace; font-size: 14px;"></textarea>
                        </div>
                    </div>
                </div>

                <!-- Main Action Button -->
                <button type="submit" class="btn btn-primary w-100 btn-action shadow">
                    <span class="spinner-border spinner-border-sm d-none" role="status" aria-hidden="true"></span>
                    <span class="btn-text">Start Processing</span>
                    <i class="bi bi-arrow-right-circle btn-icon"></i>
                </button>
            </form>

            <div id="status" class="mt-3"></div>

            <!-- Alternative Actions -->
            <div class="mt-4 pt-3 border-top border-secondary" style="border-color: #343a40 !important;">
                <div class="d-grid gap-2">
                    <a href="/images" class="btn btn-outline-secondary d-flex align-items-center justify-content-center" style="min-height: 48px;">
                        <i class="bi bi-images me-2"></i> Upload Images Instead
                    </a>
                    
                    <button class="btn btn-dark d-flex align-items-center justify-content-between px-3" type="button" data-bs-toggle="collapse" data-bs-target="#existingPdfSection" aria-expanded="false" style="min-height: 48px; border: 1px solid var(--border-color);">
                        <span><i class="bi bi-clock-history me-2"></i> Recent Files</span>
                        <i class="bi bi-chevron-down small"></i>
                    </button>
                </div>

                <div class="collapse mt-2" id="existingPdfSection">
                    <div class="card card-body bg-dark border border-secondary p-0 overflow-hidden">
                        <div class="list-group list-group-flush" style="max-height: 200px; overflow-y: auto;">
                            {% if pdfs %}
                                {% for pdf in pdfs %}
                                    <a href="/process_final_pdf/{{ pdf.id }}" class="list-group-item list-group-item-action bg-transparent text-white border-secondary">
                                        <div class="text-truncate me-2">{{ pdf.filename }}</div>
                                        <i class="bi bi-chevron-right text-secondary small"></i>
                                    </a>
                                {% endfor %}
                            {% else %}
                                <div class="p-3 text-center text-muted small">No recent files found.</div>
                            {% endif %}
                        </div>
                    </div>
                </div>
            </div>

        </div>
    </div>
</div>
{% endblock %}

{% block scripts %}
<script>
    // --- File Input UX ---
    const fileInput = document.getElementById('pdf-upload');
    const dropZone = document.getElementById('drop-zone');
    const fileLabel = document.getElementById('file-label-text');

    // Visual feedback for file selection
    fileInput.addEventListener('change', function() {
        if (this.files && this.files.length > 0) {
            fileLabel.innerHTML = `<i class="bi bi-check-circle-fill text-success"></i> ${this.files[0].name}`;
            dropZone.style.borderColor = '#198754';
            dropZone.style.background = 'rgba(25, 135, 84, 0.1)';
        } else {
            fileLabel.textContent = "Tap to select or drag PDF here";
            dropZone.style.borderColor = '';
            dropZone.style.background = '';
        }
    });

    // Drag and drop visual effects
    ['dragenter', 'dragover'].forEach(eventName => {
        dropZone.addEventListener(eventName, (e) => {
            e.preventDefault();
            e.stopPropagation();
            dropZone.classList.add('drag-over');
        }, false);
    });

    ['dragleave', 'drop'].forEach(eventName => {
        dropZone.addEventListener(eventName, (e) => {
            e.preventDefault();
            e.stopPropagation();
            dropZone.classList.remove('drag-over');
        }, false);
    });

    // --- Paste Support ---
    document.addEventListener('paste', function(event) {
        const items = (event.clipboardData || event.originalEvent.clipboardData).items;
        for (let index in items) {
            const item = items[index];
            if (item.kind === 'file') {
                const blob = item.getAsFile();
                if (blob.type === 'application/pdf') {
                    // It's a PDF!
                    // We need to create a FileList-like object or use DataTransfer to set input.files
                    const dataTransfer = new DataTransfer();
                    dataTransfer.items.add(blob);
                    fileInput.files = dataTransfer.files;

                    // Trigger change event to update UI
                    const changeEvent = new Event('change');
                    fileInput.dispatchEvent(changeEvent);
                    
                    // Switch to file tab if not active
                    const fileTabBtn = document.querySelector('#file-tab');
                    if (!fileTabBtn.classList.contains('active')) {
                        const tab = new bootstrap.Tab(fileTabBtn);
                        tab.show();
                    }
                    
                    break; 
                }
            }
        }
    });

    // --- Tab Handling ---
    const tabs = document.querySelectorAll('#uploadMethodTab .nav-link');
    tabs.forEach(tab => {
        tab.addEventListener('shown.bs.tab', function (event) {
            const currentTabId = event.target.id;
            document.getElementById('pdf-upload').required = (currentTabId === 'file-tab');
            document.getElementById('pdf-url').required = (currentTabId === 'url-tab');
            document.getElementById('curl-command').required = (currentTabId === 'curl-tab');
        });
    });
    // Set initial required state
    document.getElementById('pdf-upload').required = true;

    // --- Form Submission ---
    document.getElementById('upload-form').addEventListener('submit', async function(e) {
        e.preventDefault();
        const form = e.target;
        const button = form.querySelector('button[type="submit"]');
        const spinner = button.querySelector('.spinner-border');
        const btnText = button.querySelector('.btn-text');
        const btnIcon = button.querySelector('.btn-icon');
        const statusDiv = document.getElementById('status');

        // Reset UI
        statusDiv.innerHTML = '';
        button.disabled = true;
        spinner.classList.remove('d-none');
        btnIcon.classList.add('d-none');
        btnText.textContent = "Uploading...";

        const activeTab = document.querySelector('#uploadMethodTab .nav-link.active').id;
        const formData = new FormData();

        // Validation & Data Prep
        let isValid = false;
        if (activeTab === 'file-tab') {
            const fileInput = document.getElementById('pdf-upload');
            if (fileInput.files.length > 0) {
                formData.append('pdf', fileInput.files[0]);
                isValid = true;
            } else {
                statusDiv.innerHTML = `<div class="alert alert-danger d-flex align-items-center"><i class="bi bi-exclamation-triangle-fill me-2"></i> Please select a PDF file.</div>`;
            }
        } else if (activeTab === 'url-tab') {
            const urlInput = document.getElementById('pdf-url');
            if (urlInput.value) {
                formData.append('pdf_url', urlInput.value);
                isValid = true;
            } else {
                statusDiv.innerHTML = `<div class="alert alert-danger d-flex align-items-center"><i class="bi bi-exclamation-triangle-fill me-2"></i> Please enter a PDF URL.</div>`;
            }
        } else if (activeTab === 'curl-tab') {
            const curlInput = document.getElementById('curl-command');
            if (curlInput.value) {
                formData.append('curl_command', curlInput.value);
                isValid = true;
            } else {
                statusDiv.innerHTML = `<div class="alert alert-danger d-flex align-items-center"><i class="bi bi-exclamation-triangle-fill me-2"></i> Please enter a cURL command.</div>`;
            }
        }

        if (!isValid) {
            button.disabled = false;
            spinner.classList.add('d-none');
            btnIcon.classList.remove('d-none');
            btnText.textContent = "Start Processing";
            return;
        }

        try {
            const response = await fetch('/v2/upload', {
                method: 'POST',
                body: formData
            });

            const result = await response.json();

            if (response.ok) {
                // Success State
                button.className = "btn btn-success w-100 btn-action shadow";
                btnText.textContent = "Upload Complete!";
                spinner.classList.add('d-none');
                btnIcon.className = "bi bi-check-lg";
                btnIcon.classList.remove('d-none');
                
                statusDiv.innerHTML = `
                    <div class="alert alert-success border-0 bg-success bg-opacity-10 text-success">
                        <i class="bi bi-check-circle-fill me-2"></i> Found ${result.files.length} pages.
                    </div>
                `;
                
                // Redirect immediately or show button? 
                // UX Best practice: Show button to proceed or auto-redirect after short delay.
                // Let's replace the button with a "Start Cropping" link to be safe.
                setTimeout(() => {
                    window.location.href = `/cropv2/${result.session_id}/0`;
                }, 500); // 500ms delay to see the checkmark
                
            } else {
                throw new Error(result.error || 'Upload failed');
            }
        } catch (error) {
            statusDiv.innerHTML = `
                <div class="alert alert-danger border-0 bg-danger bg-opacity-10 text-danger">
                    <i class="bi bi-x-circle-fill me-2"></i> ${error.message}
                </div>
            `;
            button.disabled = false;
            button.className = "btn btn-primary w-100 btn-action shadow";
            spinner.classList.add('d-none');
            btnIcon.classList.remove('d-none');
            btnText.textContent = "Try Again";
        }
    });
</script>
{% endblock %}