{% extends 'generic/base.html' %}

{% load crispy_forms_tags %}
{% block css %}
{% endblock %}

{% block content %}
    <a href='{% url "trainees" %}'>All, </a>
    {% for i in "123456"|make_list %}
        <a href='{% url "trainees_grade" "ST"|add:i %}'>ST{{i}}</a>{% if not forloop.last %}, {% endif %}
    {% endfor %}
    (<a href="{% url 'create_trainee' %}" title="Click to add a trainee to the platform, creating an account for them.">Add trainee</a>)
    (<a href="{% url 'accounts_bulk_create' %}" title="Click to create multiple trainees at once.">Bulk create</a>)
    (<a href="{% url 'trainees_bulk_update_from_spreadsheet' %}" title="Click to update multiple trainees at once.">Bulk update</a>)

    <h2>
        {% if grade %}
            {{grade}}
        {% endif %}Trainees
    </h2>
    <form>
        <table id="trainees-table">
            <tr class="header">
                <th class="sortable" data-col="0">Name <span class="sort-indicator"></span></th>
                <th class="sortable" data-col="1">Grade <span class="sort-indicator"></span></th>
                <th class="sortable" data-col="2">Email <span class="sort-indicator"></span></th>
                <th class="sortable" data-col="3">Supervisor <span class="sort-indicator"></span></th>
                <th>Edit</th>
                <th class="trainee-bulk-edit">Bulk Edit<br/>
                    <span _="on click repeat for i in .trainee-checkbox
                                 toggle [@checked] on i
                             end then call updateSelectedCount()
                            ">Toggle All</span>
                </th>
            </tr>

            {% for trainee in trainees %}
                <tr class="trainee" _="on click if target.tagName is not 'INPUT' and target.tagName is not 'A' toggle [@checked] on <input/> in me end then call updateSelectedCount()">
                    <td>{{trainee.user.first_name}} {{trainee.user.last_name}}
                        <a href="{% url 'account_profile' trainee.username %}" class="opacity-25"><i class="bi bi-link"></i></a>
                    </td>
                    <td
                        {% if not trainee.grade %}
                            class="no-grade"
                        {% endif %}
                    >{{trainee.grade}}{% if not trainee.grade %}
                        <a href="{% url 'account_profile_update' trainee.user.username %}?redirect={{request.path}}" class="add-grade">add</a>
                    {% endif %}
                    </td>
                    <td>{{trainee.user.email}}</td>
                    <td
                        {% if not trainee.supervisor %}
                            class="no-supervisor"
                        {% endif %}
                    >{{trainee.supervisor}}
                        {% if not trainee.supervisor %}
                            <a href="{% url 'account_profile_update' trainee.user.username %}?redirect={{request.path}}" class="add-supervisor">add</a>
                        {% else %}
                            <a href="{% url 'generic:supervisor_detail' trainee.supervisor.pk %}" class="opacity-25"><i class="bi bi-link"></i></a>
                        {% endif %}
                    </td>
                    <td><a href="{% url 'account_update' trainee.user.username %}?redirect={{request.path}}">User</a>/<a href="{% url 'account_profile_update' trainee.user.username %}?redirect={{request.path}}">Profile</a>
                        <span class="hover-highlight remove-trainee"><i class="bi bi-x-circle" title="Click to remove trainee status"
                                                                        hx-get="{% url 'generic:user_not_trainee' trainee.user.pk %}"
                                                                        hx-target="closest tr"
                                                                        hx-swap="outerHTML swap:0.5s"
                                                                        hx-confirm="Are you sure you want to remove trainee status for this user?"
                            ></i></span>
                    </td>
                    <td class="trainee-bulk-edit">
                        <input class="trainee-checkbox" type="checkbox" name="selection" value="{{trainee.user.pk}}">
                    </td>

                </tr>
            {% endfor %}

        </table>
    </form>

    <div class="small-gray">Count: {{trainees|length}}</div>

    <button class="btn btn-sm"
            _="on click toggle .show on .remove-trainee"
    >Remove trainee status</button>
    <button class="btn btn-sm"
            _="on click toggle .show on .trainee-bulk-edit"
    >Bulk edit trainees</button>

    <div id="bulk-edit" class="trainee-bulk-edit">
        <h3>Bulk edit options</h3>
        <p class="text-muted small mb-2">Selected trainees: <span id="selected-count" class="fw-bold">0</span></p>
        These actions will act on all the selected trainees. Refresh the page to cancel / clear.
        <div id="htmx-info"></div>
        <div id="htmx-options"></div>
        <button id="bulk-delete-supervisors-button"
                title="Deletes the supervisors of all selected users"
                hx-post="{% url 'generic:users_bulk_delete_supervisors' %}"
                hx-include="[name='selection']"
                hx-confirm="This will delete supervisors from all selected users, are you sure you wish to continue?"
                hx-target="#htmx-info"
                _='on click put "" into #htmx-options'
        >Delete supervisors</button>
        <button id="bulk-edit-grade-button"
                hx-post="{% url 'generic:users_bulk_edit' %}"
                hx-include="[name='selection']"
                hx-target="#htmx-options"
                title="Changes the selected users grade."
        >Edit grade</button>
        <button id="bulk-add-group-button"
                hx-post="{% url 'generic:users_bulk_edit' %}"
                hx-include="[name='selection']"
                hx-target="#htmx-options"
                title="Adds the selected user to a group."
        >Add group</button>
        <button id="bulk-remove-group-button"
                hx-post="{% url 'generic:users_bulk_edit' %}"
                hx-include="[name='selection']"
                hx-target="#htmx-options"
                title="Removes the selected user from a group."
        >Remove group</button>
        <button id="bulk-deactivate-user-button"
                hx-post="{% url 'generic:users_bulk_edit' %}"
                hx-include="[name='selection']"
                hx-target="#htmx-options"
                hx-confirm="This will deactivate all selected users, are you sure you wish to continue?"
                title="Deactivates the selected users"
        >Deactivate</button>
    </div>

    <style>
        .add-supervisor, .add-grade {
            font-size: small;
        }
        .no-supervisor, .no-grade {
            color: red;
            opacity: 50%;
        }

        .remove-trainee, .trainee-bulk-edit {
            display: none;
        }

        #bulk-edit {
            display: none;
        }

        .show {
            display: inline !important;
        }

        td {
            padding-right: 8px;
        }

        tr:hover {
            box-shadow: 0 0 2px #ccc;

        }

        tr:has(.trainee-checkbox:checked) {
            background-color: darkgrey;
            color: white;
        }
        th.sortable {
            cursor: pointer;
            user-select: none;
        }
        th .sort-indicator {
            font-size: 0.8em;
            margin-left: 6px;
            opacity: 0.6;
        }
    </style>

    <script>
        (function(){
            const table = document.getElementById('trainees-table');
            if (!table) return;

            const getCellValue = (tr, idx) => {
                const cell = tr.children[idx];
                return cell ? cell.innerText.trim().toLowerCase() : '';
            };

            const comparer = function(idx, asc){
                return function(a,b){
                    const v1 = getCellValue(a, idx);
                    const v2 = getCellValue(b, idx);
                // attempt numeric compare
                    const n1 = parseFloat(v1.replace(/[^0-9.\-]/g, ''));
                    const n2 = parseFloat(v2.replace(/[^0-9.\-]/g, ''));
                    if (!isNaN(n1) && !isNaN(n2)){
                        return (n1 - n2) * (asc ? 1 : -1);
                    }
                    return v1.localeCompare(v2) * (asc ? 1 : -1);
                };
            };

            let lastSorted = {idx: null, asc: true};

            table.querySelectorAll('th.sortable').forEach(th => {
                th.addEventListener('click', function(){
                    const idx = parseInt(th.getAttribute('data-col'));
                    const tbodyRows = Array.from(table.querySelectorAll('tr.trainee'));
                    const asc = (lastSorted.idx === idx) ? !lastSorted.asc : true;

                    tbodyRows.sort(comparer(idx, asc));

                // re-append rows in new order
                    const parent = table;
                    tbodyRows.forEach(r => parent.appendChild(r));

                // update indicators
                    table.querySelectorAll('th.sortable .sort-indicator').forEach(el => el.textContent = '');
                    th.querySelector('.sort-indicator').textContent = asc ? '▲' : '▼';

                    lastSorted = {idx, asc};
                });
            });

            // Update selection count
            const updateSelectedCount = () => {
                const checkedCount = table.querySelectorAll('.trainee-checkbox:checked').length;
                const countEl = document.getElementById('selected-count');
                if (countEl) {
                    countEl.textContent = checkedCount;
                }
            };

            // Listen for checkbox changes directly
            table.addEventListener('change', function(e) {
                if (e.target.classList.contains('trainee-checkbox')) {
                    updateSelectedCount();
                }
            });

            // Expose to window so hyperscript can call it
            window.updateSelectedCount = updateSelectedCount;

            updateSelectedCount();
        })();
    </script>
{% endblock %}