{% extends 'django_forms_workflows/base.html' %}
{% load forms_workflows_tags %}

{% block title %}Approval History - {{ site_name }}{% endblock %}

{% block extra_css %}
<link rel="stylesheet" href="https://cdn.datatables.net/1.13.6/css/dataTables.bootstrap5.min.css">
<style>
  /* Improve pagination styling */
  .dataTables_wrapper .dataTables_paginate {
    margin-top: 0 !important;
  }

  .dataTables_wrapper .dataTables_paginate .pagination {
    margin-bottom: 0;
  }

  .dataTables_wrapper .dataTables_info {
    padding-top: 0;
  }

  /* Clean up table controls */
  .dataTables_wrapper .row {
    margin-left: 0;
    margin-right: 0;
  }

  /* Style the page length selector */
  .form-select-sm {
    border-color: #dee2e6;
    transition: border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
  }

  .form-select-sm:focus {
    border-color: #86b7fe;
    box-shadow: 0 0 0 0.25rem rgba(13, 110, 253, 0.25);
  }

  /* Improve search input styling */
  #searchContainer .input-group-text {
    border-right: 0;
  }

  #searchContainer input {
    border-left: 0;
  }

  #searchContainer input:focus {
    border-color: #dee2e6;
    box-shadow: none;
  }

  #searchContainer .input-group:focus-within .input-group-text {
    border-color: #86b7fe;
  }

  #searchContainer .input-group:focus-within input {
    border-color: #86b7fe;
    box-shadow: 0 0 0 0.25rem rgba(13, 110, 253, 0.25);
  }

  /* Column picker */
  #colPickerDropdown .dropdown-menu { max-height: 340px; overflow-y: auto; }
  #colPickerDropdown .form-check { white-space: nowrap; }

  /* PDF export modal – keep hover light so description text stays readable.
     Bootstrap's default btn-outline-* hover fills the button with the solid
     accent colour, making the muted small text invisible. */
  #bulkPdfModeModal .btn-outline-danger:hover,
  #bulkPdfModeModal .btn-outline-danger:focus {
    background-color: rgba(220, 53, 69, 0.08);
    color: inherit;
  }
  #bulkPdfModeModal .btn-outline-danger:hover .text-muted,
  #bulkPdfModeModal .btn-outline-danger:focus .text-muted {
    color: #6c757d !important;
  }
  #bulkPdfModeModal .btn-outline-primary:hover,
  #bulkPdfModeModal .btn-outline-primary:focus {
    background-color: rgba(13, 110, 253, 0.08);
    color: inherit;
  }
  #bulkPdfModeModal .btn-outline-primary:hover .text-muted,
  #bulkPdfModeModal .btn-outline-primary:focus .text-muted {
    color: #6c757d !important;
  }
</style>
{% endblock %}

{% block content %}
<div class="row">
  <div class="col-12">

    {# ── Page header ── #}
    <div class="d-flex align-items-center justify-content-between mb-3">
      <h1 class="mb-0"><i class="bi bi-inbox"></i> Approvals</h1>
    </div>

    {# ── Tab navigation ── #}
    <ul class="nav nav-tabs mb-3">
      <li class="nav-item">
        <a class="nav-link" href="{% url 'forms_workflows:approval_inbox' %}">
          <i class="bi bi-hourglass-split me-1"></i>Pending
          <span class="badge bg-primary ms-1">{{ pending_tasks_count }}</span>
        </a>
      </li>
      <li class="nav-item">
        <a class="nav-link active" href="{% url 'forms_workflows:completed_approvals' %}">
          <i class="bi bi-archive me-1"></i>Approval History
          <span class="badge bg-secondary ms-1">{{ total_count }}</span>
        </a>
      </li>
    </ul>

    <div class="d-flex align-items-center justify-content-end mb-3">
      <span class="text-muted small">
        {% if active_form %}
          Filtered to <strong>{{ active_category.name }}</strong> &rsaquo; <strong>{{ active_form.name }}</strong>
          &mdash;
          <a href="?category={{ category_slug }}" class="text-decoration-none">clear form filter</a>
        {% elif active_category %}
          Filtered to <strong>{{ active_category.name }}</strong>
          &mdash;
          <a href="?" class="text-decoration-none">clear filter</a>
        {% else %}
          {{ total_count }} completed submission{{ total_count|pluralize }} total
        {% endif %}
      </span>
    </div>

    {# ── Category filter bar ── #}
    {% if category_counts %}
    <div class="mb-3 d-flex flex-wrap gap-2 align-items-center" role="toolbar" aria-label="Filter by category">
      <span class="text-muted small fw-semibold me-1">Filter:</span>

      <a href="?"
         class="btn btn-sm {% if not category_slug %}btn-primary{% else %}btn-outline-secondary{% endif %}"
         {% if not category_slug %}aria-current="true"{% endif %}>
        All
        <span class="badge {% if not category_slug %}bg-light text-dark{% else %}bg-secondary{% endif %} ms-1">
          {{ total_count }}
        </span>
      </a>

      {% for cat in category_counts %}
      <a href="?category={{ cat.slug }}"
         class="btn btn-sm {% if category_slug == cat.slug %}btn-primary{% else %}btn-outline-secondary{% endif %}"
         {% if category_slug == cat.slug %}aria-current="true"{% endif %}>
        {% if cat.icon %}<i class="bi {{ cat.icon }} me-1"></i>{% endif %}
        {{ cat.name }}
        <span class="badge {% if category_slug == cat.slug %}bg-light text-dark{% else %}bg-secondary{% endif %} ms-1">
          {{ cat.count }}
        </span>
      </a>
      {% endfor %}
    </div>
    {% endif %}

    {# ── Form filter bar (only when a category is active) ── #}
    {% if form_counts %}
    <div class="mb-3 d-flex flex-wrap gap-2 align-items-center ps-3 border-start border-2"
         role="toolbar" aria-label="Filter by form">
      <span class="text-muted small fw-semibold me-1">Form:</span>

      <a href="?category={{ category_slug }}"
         class="btn btn-sm {% if not form_slug %}btn-primary{% else %}btn-outline-secondary{% endif %}"
         {% if not form_slug %}aria-current="true"{% endif %}>
        All
      </a>

      {% for form_item in form_counts %}
      <a href="?category={{ category_slug }}&form={{ form_item.slug }}"
         class="btn btn-sm {% if form_slug == form_item.slug %}btn-primary{% else %}btn-outline-secondary{% endif %}"
         {% if form_slug == form_item.slug %}aria-current="true"{% endif %}>
        {{ form_item.name }}
        <span class="badge {% if form_slug == form_item.slug %}bg-light text-dark{% else %}bg-secondary{% endif %} ms-1">
          {{ form_item.count }}
        </span>
      </a>
      {% endfor %}
    </div>
    {% endif %}

    {# ── Status filter bar with search ── #}
    <div class="mb-3 d-flex flex-wrap gap-2 align-items-center justify-content-between" role="toolbar" aria-label="Filter by status">
      <div class="d-flex flex-wrap gap-2 align-items-center">
        <span class="text-muted small fw-semibold me-1">Status:</span>
        <a href="?{% if category_slug %}category={{ category_slug }}&{% endif %}{% if form_slug %}form={{ form_slug }}&{% endif %}"
           class="btn btn-sm {% if not status_filter %}btn-primary{% else %}btn-outline-secondary{% endif %}">
          All
        </a>
        <a href="?{% if category_slug %}category={{ category_slug }}&{% endif %}{% if form_slug %}form={{ form_slug }}&{% endif %}status=approved"
           class="btn btn-sm {% if status_filter == 'approved' %}btn-success{% else %}btn-outline-success{% endif %}">
          <i class="bi bi-check-circle me-1"></i>Approved
        </a>
        <a href="?{% if category_slug %}category={{ category_slug }}&{% endif %}{% if form_slug %}form={{ form_slug }}&{% endif %}status=rejected"
           class="btn btn-sm {% if status_filter == 'rejected' %}btn-danger{% else %}btn-outline-danger{% endif %}">
          <i class="bi bi-x-circle me-1"></i>Rejected
        </a>
        <a href="?{% if category_slug %}category={{ category_slug }}&{% endif %}{% if form_slug %}form={{ form_slug }}&{% endif %}status=withdrawn"
           class="btn btn-sm {% if status_filter == 'withdrawn' %}btn-secondary{% else %}btn-outline-secondary{% endif %}">
          <i class="bi bi-dash-circle me-1"></i>Withdrawn
        </a>
        <a href="?{% if category_slug %}category={{ category_slug }}&{% endif %}{% if form_slug %}form={{ form_slug }}&{% endif %}status=pending_approval"
           class="btn btn-sm {% if status_filter == 'pending_approval' %}btn-warning text-dark{% else %}btn-outline-warning{% endif %}">
          <i class="bi bi-hourglass-split me-1"></i>Pending Approval
        </a>
      </div>
      <div id="searchContainer"></div>
    </div>

    {# ── Hidden PDF bulk export form (populated by JS before submit) ── #}
    {% if any_pdf_exportable %}
    <form id="bulkPdfExportForm" method="post" action="{% url 'forms_workflows:bulk_export_submissions_pdf' %}" data-download-spinner="Generating PDF…" class="d-none">
      {% csrf_token %}
      <div id="pdfSubmissionIds"></div>
    </form>

    {# ── PDF export mode selection modal ── #}
    <div class="modal fade" id="bulkPdfModeModal" tabindex="-1" aria-labelledby="bulkPdfModeModalLabel" aria-hidden="true">
      <div class="modal-dialog modal-dialog-centered modal-lg">
        <div class="modal-content">
          <div class="modal-header border-0 pb-0">
            <h5 class="modal-title fw-bold" id="bulkPdfModeModalLabel">
              <i class="bi bi-file-earmark-pdf text-danger me-2"></i>Choose PDF Export Format
            </h5>
            <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close"></button>
          </div>
          <div class="modal-body pt-2 pb-4">
            <p class="text-muted mb-4">Select how you'd like to download the selected submissions as PDF files:</p>
            <div class="row g-3">
              <div class="col-md-6">
                <button type="button" class="btn btn-outline-danger w-100 h-100 p-4 text-start rounded-3 border-2"
                        onclick="submitBulkPdfMerged()" data-bs-dismiss="modal">
                  <div class="d-flex align-items-start gap-3">
                    <i class="bi bi-file-earmark-pdf fs-2 text-danger flex-shrink-0 mt-1"></i>
                    <div>
                      <div class="fw-bold fs-6 mb-1">Single Merged PDF</div>
                      <small class="text-muted">All selected submissions combined into one PDF document, separated by page breaks. Great for printing or sharing as one file.</small>
                    </div>
                  </div>
                </button>
              </div>
              <div class="col-md-6">
                <button type="button" class="btn btn-outline-primary w-100 h-100 p-4 text-start rounded-3 border-2"
                        onclick="submitBulkPdfSequential()" data-bs-dismiss="modal">
                  <div class="d-flex align-items-start gap-3">
                    <i class="bi bi-files fs-2 text-primary flex-shrink-0 mt-1"></i>
                    <div>
                      <div class="fw-bold fs-6 mb-1">Individual PDFs</div>
                      <small class="text-muted">Each submission downloaded as its own separate PDF file. Ideal when you need individual files for archiving or distribution.</small>
                    </div>
                  </div>
                </button>
              </div>
            </div>
          </div>
        </div>
      </div>
    </div>
    {% endif %}

    {# ── Bulk export form (Excel + PDF buttons, wraps the table) ── #}
    {% if any_exportable or any_pdf_exportable %}
    <form id="bulkExportForm" method="post" action="{% url 'forms_workflows:bulk_export_submissions' %}" data-download-spinner="Generating Excel…">
      {% csrf_token %}
      <div class="mb-2 d-flex align-items-center gap-2">
        {% if any_exportable %}
        <button type="submit" class="btn btn-sm btn-success" id="exportBtn" disabled>
          <i class="bi bi-file-earmark-spreadsheet me-1"></i>Export Selected to Excel
        </button>
        {% endif %}
        {% if any_pdf_exportable %}
        <button type="button" class="btn btn-sm btn-danger" id="pdfExportBtn" disabled
                data-bs-toggle="modal" data-bs-target="#bulkPdfModeModal">
          <i class="bi bi-file-earmark-pdf me-1"></i>Export Selected to PDF
        </button>
        {% endif %}
        <span class="text-muted small" id="selectedCount"></span>
      </div>
    {% endif %}

    {# ── Submissions table — body populated via server-side AJAX ── #}
    <div class="table-responsive">
      <table class="table table-hover" id="completedTable">
        <thead>
          <tr>
            {% if any_exportable or any_pdf_exportable %}<th class="text-center" style="width:40px;"><input type="checkbox" id="selectAll" title="Select all on page"></th>{% endif %}
            <th>Actions</th>
            {% if not category_slug %}<th>Category</th>{% endif %}
            <th>Form</th>
            <th>Submitter</th>
            <th>Status</th>
            <th>Submitted</th>
            <th>Completed</th>
            {% for field in form_fields %}<th class="extra-form-col" data-field="{{ field.field_name }}">{{ field.field_label }}</th>{% endfor %}
          </tr>
        </thead>
        <tbody></tbody>
      </table>
    </div>

    {% if any_exportable or any_pdf_exportable %}
    </form>
    {% endif %}

  </div>
</div>

{% if form_fields %}
{# Column picker dropdown – hidden in-place; JS moves it next to the search box #}
<div class="dropdown d-none" id="colPickerDropdown">
  <button class="btn btn-sm btn-outline-secondary" type="button"
          data-bs-toggle="dropdown" data-bs-auto-close="outside"
          aria-expanded="false" title="Customize columns">
    <i class="bi bi-gear-fill"></i>
  </button>
  <div class="dropdown-menu dropdown-menu-end p-3" style="min-width: 220px;">
    <div class="d-flex justify-content-between align-items-center mb-2">
      <span class="fw-semibold small text-muted">Additional columns</span>
      <button type="button" class="btn btn-link btn-sm p-0 small text-decoration-none" id="colToggleAll">Select all</button>
    </div>
    <hr class="my-1">
    {% for field in form_fields %}
    <div class="form-check">
      <input class="form-check-input col-toggle-chk" type="checkbox"
             id="col_chk_{{ field.field_name }}"
             data-field="{{ field.field_name }}">
      <label class="form-check-label small" for="col_chk_{{ field.field_name }}">
        {{ field.field_label }}
      </label>
    </div>
    {% endfor %}
  </div>
</div>
{% endif %}
{% endblock %}

{% block extra_js %}
<script src="https://code.jquery.com/jquery-3.7.1.min.js"></script>
<script src="https://cdn.datatables.net/1.13.6/js/jquery.dataTables.min.js"></script>
<script src="https://cdn.datatables.net/1.13.6/js/dataTables.bootstrap5.min.js"></script>
<script>
$(document).ready(function() {
    if ($('#completedTable').length) {
        var LS_PAGE_KEY = 'completed_page_len';
        var savedPageLen = parseInt(localStorage.getItem(LS_PAGE_KEY)) || 25;

        // Build colIndexMap BEFORE DataTables init so the column picker can
        // reference extra-column indices (thead <th> indices stay stable).
        var colIndexMap = {};
        var extraColTargets = [];
        $('#completedTable thead th.extra-form-col').each(function() {
            var idx = $(this).index();
            extraColTargets.push(idx);
            colIndexMap[$(this).data('field')] = idx;
        });

        var colDefs = [
            { orderable: false, targets: {% if any_exportable or any_pdf_exportable %}1{% else %}0{% endif %} }
            {% if any_exportable or any_pdf_exportable %}, { orderable: false, targets: 0 }{% endif %}
            {# status already has orderable:false in the columns[] definition — no colDef needed #}
        ];
        if (extraColTargets.length) {
            colDefs.push({ visible: false, targets: extraColTargets, orderable: false });
        }

        var table = $('#completedTable').DataTable({
            serverSide: true,
            processing: true,
            searchDelay: 400,
            ajax: {
                url: '{% url "forms_workflows:completed_approvals_ajax" %}',
                type: 'POST',
                data: function(d) {
                    d.csrfmiddlewaretoken = '{{ csrf_token }}';
                    {% if category_slug %}d.category = '{{ category_slug|escapejs }}';{% endif %}
                    {% if form_slug %}d.form = '{{ form_slug|escapejs }}';{% endif %}
                    {% if status_filter %}d.status = '{{ status_filter|escapejs }}';{% endif %}
                }
            },
            columns: [
                {% if any_exportable or any_pdf_exportable %}{ data: 'checkbox', name: '', orderable: false, className: 'text-center' },{% endif %}
                { data: 'actions', name: '', orderable: false },
                {% if not category_slug %}{ data: 'category', name: 'form_definition__category__name' },{% endif %}
                { data: 'form', name: 'form_definition__name' },
                { data: 'submitter', name: 'submitter__last_name' },
                { data: 'status', name: 'status', orderable: false },
                { data: 'submitted_at', name: 'submitted_at' },
                { data: 'completed_at', name: 'completed_at' },
                {% for field in form_fields %}{ data: '{{ field.field_name }}', name: '', orderable: false },{% endfor %}
            ],
            order: [[{{ default_sort_col }}, 'desc']],
            columnDefs: colDefs,
            pageLength: savedPageLen,
            dom: '<"row"<"col-sm-12"tr>><"row mt-3"<"col-sm-12 col-md-5"i><"col-sm-12 col-md-7"p>>',
            language: {
                search: '',
                searchPlaceholder: 'Search submissions...',
                emptyTable: 'No completed submissions found.',
                zeroRecords: 'No matching submissions found.',
                info: 'Showing _START_ to _END_ of _TOTAL_ submissions',
                infoEmpty: 'Showing 0 to 0 of 0 submissions',
                infoFiltered: '(filtered from _MAX_ total submissions)',
                processing: '<div class="text-center py-3"><div class="spinner-border spinner-border-sm text-secondary" role="status"></div> Loading…</div>',
                paginate: {
                    first: '&laquo;',
                    last: '&raquo;',
                    next: '&rsaquo;',
                    previous: '&lsaquo;'
                }
            }
        });

        // Build search box
        var searchBox = $('<div class="input-group input-group-sm" style="max-width: 300px;">' +
            '<span class="input-group-text bg-white"><i class="bi bi-search"></i></span>' +
            '<input type="search" class="form-control form-control-sm" placeholder="Search submissions..." aria-label="Search">' +
            '</div>');

        searchBox.find('input').on('keyup change', function() {
            table.search(this.value).draw();
        });

        {% if form_fields %}
        // ── Column picker ──────────────────────────────────────────────────
        var LS_KEY = 'completed_col_prefs_{{ form_slug }}';
        var $picker = $('#colPickerDropdown');

        // Place search + gear together in the search container, then
        // reveal the picker (d-none removed AFTER move to avoid layout
        // flash / horizontal scrollbar from the out-of-grid element).
        var $controls = $('<div class="d-flex align-items-center gap-2"></div>');
        $controls.append(searchBox).append($picker);
        $('#searchContainer').append($controls);
        $picker.removeClass('d-none');

        // colIndexMap was built above BEFORE DataTables init.

        // Restore saved column preferences from localStorage
        var savedCols = [];
        try {
            var stored = localStorage.getItem(LS_KEY);
            if (stored) savedCols = JSON.parse(stored);
        } catch(e) { savedCols = []; }

        // Restore visibility without triggering a separate AJAX redraw per column.
        // Passing false as the second argument to visible() suppresses the redraw;
        // we do a single columns.adjust().draw() at the end instead.
        // Reset the table node's cached inline width then recalculate.
        // Without clearing style.width first, DataTables keeps the wider
        // measurement from when extra columns were visible, leaving the
        // table spaced out after columns are hidden.
        function adjustTable() {
            table.table().node().style.width = '';
            table.columns.adjust().draw(false);
        }

        var anyRestored = false;
        savedCols.forEach(function(fieldName) {
            if (colIndexMap[fieldName] !== undefined) {
                table.column(colIndexMap[fieldName]).visible(true, false);
                $('#col_chk_' + fieldName).prop('checked', true);
                anyRestored = true;
            }
        });
        if (anyRestored) {
            adjustTable();
        }

        // Update the Select all / Deselect all link label
        function updateToggleAllLabel() {
            var total = $('.col-toggle-chk').length;
            var checked = $('.col-toggle-chk:checked').length;
            $('#colToggleAll').text(checked === total ? 'Deselect all' : 'Select all');
        }
        updateToggleAllLabel();

        // Select all / Deselect all – suppress per-column redraws; do one at the end.
        $('#colToggleAll').on('click', function() {
            var allChecked = $('.col-toggle-chk:checked').length === $('.col-toggle-chk').length;
            $('.col-toggle-chk').each(function() {
                var fieldName = $(this).data('field');
                if (colIndexMap[fieldName] !== undefined) {
                    $(this).prop('checked', !allChecked);
                    table.column(colIndexMap[fieldName]).visible(!allChecked, false);
                }
            });
            adjustTable();
            var visible = !allChecked
                ? $('.col-toggle-chk').map(function() { return $(this).data('field'); }).get()
                : [];
            try { localStorage.setItem(LS_KEY, JSON.stringify(visible)); } catch(e) {}
            updateToggleAllLabel();
        });

        // Toggle individual column visibility and persist preference
        $(document).on('change', '.col-toggle-chk', function() {
            var fieldName = $(this).data('field');
            if (colIndexMap[fieldName] !== undefined) {
                table.column(colIndexMap[fieldName]).visible(this.checked, false);
                adjustTable();
            }
            var visible = [];
            $('.col-toggle-chk:checked').each(function() { visible.push($(this).data('field')); });
            try { localStorage.setItem(LS_KEY, JSON.stringify(visible)); } catch(e) {}
            updateToggleAllLabel();
        });
        {% else %}
        $('#searchContainer').append(searchBox);
        {% endif %}

        // Add page length selector to bottom with improved styling
        var lengthSelect = $('<div class="d-flex align-items-center gap-2 mb-2">' +
            '<label class="mb-0 text-muted small">Show:</label>' +
            '<select class="form-select form-select-sm" style="width: auto;">' +
            '<option value="10">10</option>' +
            '<option value="25">25</option>' +
            '<option value="50">50</option>' +
            '<option value="100">100</option>' +
            '<option value="250">250</option>' +
            '<option value="500">500</option>' +
            '<option value="1000">1000</option>' +
            '</select>' +
            '<span class="text-muted small">entries</span>' +
            '</div>');

        // Sync dropdown to the restored page length (localStorage or default)
        lengthSelect.find('select').val(savedPageLen);

        lengthSelect.find('select').on('change', function() {
            var len = parseInt($(this).val());
            table.page.len(len).draw();
            try { localStorage.setItem(LS_PAGE_KEY, len); } catch(e) {}
        });

        $('.dataTables_info').parent().prepend(lengthSelect);
    }

    // Bulk export checkbox handling
    {% if any_exportable or any_pdf_exportable %}
    function updateExportBtn() {
        var checked = $('.export-check:checked').length;
        $('#exportBtn').prop('disabled', checked === 0);
        $('#pdfExportBtn').prop('disabled', checked === 0);
        $('#selectedCount').text(checked > 0 ? checked + ' selected' : '');
    }

    $('#selectAll').on('change', function() {
        var checked = $(this).prop('checked');
        if (table) {
            table.$('.export-check').prop('checked', checked);
        } else {
            $('.export-check').prop('checked', checked);
        }
        $('.export-check').trigger('change');
    });

    $(document).on('change', '.export-check', function() {
        updateExportBtn();
        if (!$(this).prop('checked')) {
            $('#selectAll').prop('checked', false);
        }
    });
    {% endif %}
});

// ── Bulk PDF export helpers (called from the mode-selection modal) ──
{% if any_pdf_exportable %}
var _bulkPdfSingleUrl = "{% url 'forms_workflows:submission_pdf' 0 %}";

function submitBulkPdfMerged() {
    // Existing behaviour: all submissions combined into one PDF.
    var pdfForm = document.getElementById('bulkPdfExportForm');
    var container = document.getElementById('pdfSubmissionIds');
    container.innerHTML = '';
    document.querySelectorAll('.export-check:checked').forEach(function(cb) {
        var inp = document.createElement('input');
        inp.type = 'hidden';
        inp.name = 'submission_ids';
        inp.value = cb.value;
        container.appendChild(inp);
    });
    pdfForm.requestSubmit();
}

function submitBulkPdfSequential() {
    // New behaviour: download each submission as its own PDF file, one at a time.
    var ids = [];
    document.querySelectorAll('.export-check:checked').forEach(function(cb) {
        ids.push(cb.value);
    });
    if (!ids.length) return;

    var total = ids.length;
    var index = 0;
    var overlay = document.getElementById('loadingOverlay');
    var msg = document.getElementById('loadingMessage');
    if (overlay) overlay.classList.add('active');

    function downloadNext() {
        if (index >= ids.length) {
            if (overlay) overlay.classList.remove('active');
            return;
        }
        var id = ids[index++];
        if (msg) msg.textContent = 'Downloading PDF ' + index + ' of ' + total + '\u2026';
        var url = _bulkPdfSingleUrl.replace('/0/', '/' + id + '/');
        fetch(url)
            .then(function(resp) {
                if (!resp.ok) throw new Error('HTTP ' + resp.status);
                var cd = resp.headers.get('Content-Disposition') || '';
                var m = cd.match(/filename[^;=\n]*=["']?([^"';\n]+)["']?/i);
                var filename = (m && m[1]) ? m[1].trim() : ('submission_' + id + '.pdf');
                return resp.blob().then(function(blob) { return { blob: blob, name: filename }; });
            })
            .then(function(data) {
                var blobUrl = URL.createObjectURL(data.blob);
                var a = document.createElement('a');
                a.href = blobUrl;
                a.download = data.name;
                document.body.appendChild(a);
                a.click();
                document.body.removeChild(a);
                setTimeout(function() { URL.revokeObjectURL(blobUrl); }, 10000);
                setTimeout(downloadNext, 800);
            })
            .catch(function(err) {
                console.error('PDF download failed for submission ' + id + ':', err);
                setTimeout(downloadNext, 800);
            });
    }
    downloadNext();
}
{% endif %}
</script>
{% endblock %}