{% extends "admin/base_site.html" %}
{% load i18n %}

{% block title %}{{ title }} | {{ site_title|default:_('Django site admin') }}{% endblock %}

{% block content %}
<div class="content-main">
    <h1>{{ title }}</h1>
    
    <div class="alert alert-info" style="margin: 10px 0; padding: 10px; border-radius: 4px; background-color: #d1ecf1; border: 1px solid #bee5eb; color: #0c5460;">
        <strong>Note:</strong> This operation only affects the database and works even if servers are unreachable. 
        Server connectivity is not required for moving links between servers.
    </div>
    
    {% if messages %}
        {% for message in messages %}
            <div class="alert alert-{{ message.tags }}" style="margin: 10px 0; padding: 10px; border-radius: 4px; 
                {% if message.tags == 'error' %}background-color: #f8d7da; border: 1px solid #f5c6cb; color: #721c24;
                {% elif message.tags == 'success' %}background-color: #d4edda; border: 1px solid #c3e6cb; color: #155724;
                {% elif message.tags == 'warning' %}background-color: #fff3cd; border: 1px solid #ffeaa7; color: #856404;
                {% elif message.tags == 'info' %}background-color: #d1ecf1; border: 1px solid #bee5eb; color: #0c5460;
                {% endif %}">
                {{ message }}
            </div>
        {% endfor %}
    {% endif %}

    <form method="post" id="move-clients-form">
        {% csrf_token %}
        
        <div class="form-row" style="margin-bottom: 20px;">
            <div style="display: flex; gap: 20px;">
                <div style="flex: 1;">
                    <label for="source_server"><strong>Source Server:</strong></label>
                    <select id="source_server" name="source_server" style="width: 100%; padding: 5px;" onchange="updateLinksList()">
                        <option value="">-- Select Source Server --</option>
                        {% for server in servers %}
                            <option value="{{ server.id }}">{{ server.name }} ({{ server.server_type }})</option>
                        {% endfor %}
                    </select>
                </div>
                
                <div style="flex: 1;">
                    <label for="target_server"><strong>Target Server:</strong></label>
                    <select id="target_server" name="target_server" style="width: 100%; padding: 5px;" onchange="updateSubmitButton()">
                        <option value="">-- Select Target Server --</option>
                        {% for server in all_servers %}
                            <option value="{{ server.id }}">{{ server.name }} ({{ server.server_type }})</option>
                        {% endfor %}
                    </select>
                </div>
            </div>
        </div>

        <div id="links-list" style="margin-bottom: 20px;">
            <h3>Select Client Links to Move:</h3>
            <div id="links-container">
                <p style="color: #666;">Please select a source server first.</p>
            </div>
        </div>

        <!-- REGEX TRANSFORMATION SECTION -->
        <div class="form-row" style="margin-bottom: 20px; border: 2px solid #007cba; border-radius: 8px; padding: 20px; background-color: #f8f9fa;">
            <h3 style="margin-top: 0; color: #007cba;">📝 Comment Transformation (Optional)</h3>
            
            <div style="margin-bottom: 15px;">
                <label for="comment_regex"><strong>Regular Expression Pattern:</strong></label>
                <input type="text" id="comment_regex" name="comment_regex" 
                       style="width: 100%; padding: 10px; font-family: 'Courier New', monospace; font-size: 14px; border: 2px solid #ddd; border-radius: 4px;" 
                       placeholder="Example: ^(.*)$ -> [OLD_SERVER] $1"
                       title="Use regex pattern -> replacement format">
                <small style="color: #666; display: block; margin-top: 5px;">
                    Format: <code>pattern -> replacement</code> (leave empty to keep original comments)
                </small>
            </div>
            
            <div class="regex-help" style="background-color: #ffffff; padding: 15px; border-radius: 5px; border: 1px solid #dee2e6;">
                <h4 style="margin-top: 0; color: #007cba;">🔧 Regular Expression Help & Examples:</h4>
                <div style="font-size: 14px;">
                    
                    <div style="display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-top: 10px;">
                        <div>
                            <h5 style="color: #28a745;">✨ Common Examples:</h5>
                            <ul style="margin: 5px 0; padding-left: 20px; line-height: 1.6;">
                                <li><code>^(.*)$ -> [ServerA] $1</code><br><small style="color: #666;">Add prefix to all comments</small></li>
                                <li><code>^(.*)$ -> $1 (moved)</code><br><small style="color: #666;">Add suffix to all comments</small></li>
                                <li><code>^$ -> Default Device</code><br><small style="color: #666;">Replace empty comments</small></li>
                                <li><code>phone -> mobile</code><br><small style="color: #666;">Replace specific word</small></li>
                                <li><code>^(.*)(phone|mobile)(.*)$ -> $1device$3</code><br><small style="color: #666;">Replace phone/mobile with device</small></li>
                            </ul>
                        </div>
                        
                        <div>
                            <h5 style="color: #dc3545;">🚀 Advanced Examples:</h5>
                            <ul style="margin: 5px 0; padding-left: 20px; line-height: 1.6;">
                                <li><code>^(.+) - (.+)$ -> $2: $1</code><br><small style="color: #666;">Swap parts separated by " - "</small></li>
                                <li><code>(\d{4})-(\d{2})-(\d{2}) -> $3/$2/$1</code><br><small style="color: #666;">Change date format YYYY-MM-DD to DD/MM/YYYY</small></li>
                                <li><code>^(.{1,20}).*$ -> $1...</code><br><small style="color: #666;">Truncate long comments to 20 chars</small></li>
                                <li><code>([a-zA-Z]+)\s+(\d+) -> $1_$2</code><br><small style="color: #666;">Replace spaces with underscores in "word number"</small></li>
                            </ul>
                        </div>
                    </div>
                    
                    <div style="margin-top: 15px; padding: 12px; background-color: #fff3cd; border-radius: 5px; border-left: 4px solid #ffc107;">
                        <strong>💡 Tips:</strong>
                        <ul style="margin: 8px 0; padding-left: 20px; font-size: 13px; line-height: 1.5;">
                            <li>Use <code>$1, $2, $3...</code> to reference captured groups in parentheses</li>
                            <li>Use <code>^</code> for start of string, <code>$</code> for end of string</li>
                            <li>Use <code>.*</code> to match any characters, <code>.+</code> to match one or more characters</li>
                            <li>Test your regex carefully - invalid patterns will show an error</li>
                            <li>Leave empty to keep original comments unchanged</li>
                        </ul>
                    </div>
                </div>
            </div>
        </div>

        <div class="submit-row">
            <input type="submit" value="Move Selected Links" class="default" id="submit-btn" disabled>
            <a href="{% url 'admin:vpn_server_changelist' %}" class="button cancel">Cancel</a>
        </div>
    </form>
</div>

<script>
// Client links data for each server
var linksByServer = {
    {% for server, links in links_by_server.items %}
        "{{ server.id }}": [
            {% for link in links %}
                {
                    "id": {{ link.id }},
                    "link": "{{ link.link|escapejs }}",
                    "comment": "{{ link.comment|escapejs }}",
                    "username": "{{ link.acl.user.username|escapejs }}",
                    "user_comment": "{{ link.acl.user.comment|escapejs }}",
                    "created_at": "{{ link.acl.created_at|date:'Y-m-d H:i' }}",
                    "full_url": "{{ EXTERNAL_ADDRESS }}/ss/{{ link.link }}#{{ link.acl.server.name|escapejs }}"
                },
            {% endfor %}
        ],
    {% endfor %}
};

function updateLinksList() {
    var sourceServerId = document.getElementById('source_server').value;
    var linksContainer = document.getElementById('links-container');
    var submitBtn = document.getElementById('submit-btn');
    
    if (!sourceServerId) {
        linksContainer.innerHTML = '<p style="color: #666;">Please select a source server first.</p>';
        submitBtn.disabled = true;
        return;
    }
    
    var links = linksByServer[sourceServerId] || [];
    
    if (links.length === 0) {
        linksContainer.innerHTML = '<p style="color: #666;">No client links found for this server.</p>';
        submitBtn.disabled = true;
        return;
    }
    
    // Group links by user for better organization
    var linksByUser = {};
    links.forEach(function(link) {
        if (!linksByUser[link.username]) {
            linksByUser[link.username] = {
                user_comment: link.user_comment,
                created_at: link.created_at,
                links: []
            };
        }
        linksByUser[link.username].links.push(link);
    });
    
    var html = '<div style="max-height: 500px; overflow-y: auto; border: 1px solid #ddd; padding: 10px;">';
    html += '<div style="margin-bottom: 10px;">';
    html += '<button type="button" onclick="toggleAllLinks()" style="padding: 5px 10px; margin-right: 10px;">Select All</button>';
    html += '<button type="button" onclick="toggleAllLinks(false)" style="padding: 5px 10px;">Deselect All</button>';
    html += '</div>';
    
    html += '<table style="width: 100%; border-collapse: collapse;">';
    html += '<thead><tr style="background-color: #f5f5f5;">';
    html += '<th style="padding: 8px; border: 1px solid #ddd; width: 50px;">Select</th>';
    html += '<th style="padding: 8px; border: 1px solid #ddd;">Username</th>';
    html += '<th style="padding: 8px; border: 1px solid #ddd;">Link Comment</th>';
    html += '<th style="padding: 8px; border: 1px solid #ddd;">Link ID</th>';
    html += '<th style="padding: 8px; border: 1px solid #ddd;">User Comment</th>';
    html += '<th style="padding: 8px; border: 1px solid #ddd;">Created</th>';
    html += '</tr></thead><tbody>';
    
    // Sort users alphabetically
    var sortedUsers = Object.keys(linksByUser).sort();
    
    sortedUsers.forEach(function(username) {
        var userData = linksByUser[username];
        var userLinks = userData.links;
        
        // Add user row header if user has multiple links
        if (userLinks.length > 1) {
            html += '<tr style="background-color: #f9f9f9;">';
            html += '<td style="padding: 8px; border: 1px solid #ddd; text-align: center;">';
            html += '<input type="checkbox" class="user-checkbox" data-username="' + username + '" onchange="toggleUserLinks(\'' + username + '\')">';
            html += '</td>';
            html += '<td colspan="5" style="padding: 8px; border: 1px solid #ddd;"><strong>' + username + '</strong> (' + userLinks.length + ' links)</td>';
            html += '</tr>';
        }
        
        // Add individual link rows
        userLinks.forEach(function(link) {
            html += '<tr class="link-row" data-username="' + username + '">';
            html += '<td style="padding: 8px; border: 1px solid #ddd; text-align: center;">';
            html += '<input type="checkbox" name="selected_links" value="' + link.id + '" class="link-checkbox" data-username="' + username + '" onchange="updateSubmitButton(); updateUserCheckbox(\'' + username + '\'); updateRegexPreview()">';
            html += '</td>';
            html += '<td style="padding: 8px; border: 1px solid #ddd;">' + (userLinks.length === 1 ? '<strong>' + username + '</strong>' : '↳') + '</td>';
            html += '<td style="padding: 8px; border: 1px solid #ddd;">' + (link.comment || '<em>No comment</em>') + '</td>';
            html += '<td style="padding: 8px; border: 1px solid #ddd; font-family: monospace; font-size: 12px;">' + link.link + '</td>';
            html += '<td style="padding: 8px; border: 1px solid #ddd;">' + (userData.user_comment || '') + '</td>';
            html += '<td style="padding: 8px; border: 1px solid #ddd;">' + userData.created_at + '</td>';
            html += '</tr>';
        });
    });
    
    html += '</tbody></table></div>';
    linksContainer.innerHTML = html;
    
    updateSubmitButton();
}

function toggleAllLinks(selectAll = true) {
    var checkboxes = document.getElementsByName('selected_links');
    var userCheckboxes = document.getElementsByClassName('user-checkbox');
    
    for (var i = 0; i < checkboxes.length; i++) {
        checkboxes[i].checked = selectAll;
    }
    
    for (var i = 0; i < userCheckboxes.length; i++) {
        userCheckboxes[i].checked = selectAll;
    }
    
    updateSubmitButton();
    updateRegexPreview();
}

function toggleUserLinks(username) {
    var userCheckbox = document.querySelector('.user-checkbox[data-username="' + username + '"]');
    var userLinkCheckboxes = document.querySelectorAll('.link-checkbox[data-username="' + username + '"]');
    
    for (var i = 0; i < userLinkCheckboxes.length; i++) {
        userLinkCheckboxes[i].checked = userCheckbox.checked;
    }
    
    updateSubmitButton();
    updateRegexPreview();
}

function updateUserCheckbox(username) {
    var userLinkCheckboxes = document.querySelectorAll('.link-checkbox[data-username="' + username + '"]');
    var userCheckbox = document.querySelector('.user-checkbox[data-username="' + username + '"]');
    
    if (!userCheckbox) return; // No user checkbox for single-link users
    
    var allChecked = true;
    var noneChecked = true;
    
    for (var i = 0; i < userLinkCheckboxes.length; i++) {
        if (userLinkCheckboxes[i].checked) {
            noneChecked = false;
        } else {
            allChecked = false;
        }
    }
    
    if (allChecked) {
        userCheckbox.checked = true;
        userCheckbox.indeterminate = false;
    } else if (noneChecked) {
        userCheckbox.checked = false;
        userCheckbox.indeterminate = false;
    } else {
        userCheckbox.checked = false;
        userCheckbox.indeterminate = true;
    }
}

function updateSubmitButton() {
    var checkboxes = document.getElementsByName('selected_links');
    var sourceServer = document.getElementById('source_server').value;
    var targetServer = document.getElementById('target_server').value;
    var submitBtn = document.getElementById('submit-btn');
    
    var hasSelected = false;
    for (var i = 0; i < checkboxes.length; i++) {
        if (checkboxes[i].checked) {
            hasSelected = true;
            break;
        }
    }
    
    submitBtn.disabled = !(hasSelected && sourceServer && targetServer && sourceServer !== targetServer);
}

// Add regex preview functionality
document.getElementById('comment_regex').addEventListener('input', function() {
    updateRegexPreview();
});

function updateRegexPreview() {
    var regexInput = document.getElementById('comment_regex').value.trim();
    
    // Remove any existing preview
    var existingPreview = document.getElementById('regex-preview');
    if (existingPreview) {
        existingPreview.remove();
    }
    
    if (!regexInput) return;
    
    // Parse pattern -> replacement format
    var parts = regexInput.split(' -> ');
    if (parts.length !== 2) {
        showRegexError('Invalid format. Use: pattern -> replacement');
        return;
    }
    
    var pattern = parts[0];
    var replacement = parts[1];
    
    try {
        var regex = new RegExp(pattern, 'g');
        
        // Test with sample comments from currently selected links
        var sampleComments = getSampleComments();
        if (sampleComments.length > 0) {
            showRegexPreview(sampleComments, regex, replacement);
        }
        
    } catch (e) {
        showRegexError('Invalid regex pattern: ' + e.message);
    }
}

function getSampleComments() {
    var comments = [];
    var checkboxes = document.getElementsByName('selected_links');
    
    for (var i = 0; i < checkboxes.length && comments.length < 5; i++) {
        if (checkboxes[i].checked) {
            var row = checkboxes[i].closest('tr');
            var commentCell = row.children[2]; // Link Comment column
            var commentText = commentCell.textContent.trim();
            if (commentText && commentText !== 'No comment') {
                comments.push(commentText);
            } else {
                comments.push(''); // Include empty comments
            }
        }
    }
    
    // Add some default samples if no selected links
    if (comments.length === 0) {
        comments = ['iPhone 13', 'Work Laptop', 'Home Router', '', 'Android Phone'];
    }
    
    return comments;
}

function showRegexPreview(samples, regex, replacement) {
    var previewHtml = '<div id="regex-preview" style="margin-top: 15px; padding: 15px; background-color: #e8f5e8; border-radius: 5px; border-left: 4px solid #28a745;">';
    previewHtml += '<h5 style="margin-top: 0; color: #28a745;">✅ Preview (selected links):</h5>';
    previewHtml += '<table style="width: 100%; font-size: 13px; border-collapse: collapse;">';
    previewHtml += '<tr style="background-color: rgba(40, 167, 69, 0.1);"><th style="text-align: left; padding: 8px; border: 1px solid #28a745;">Original</th><th style="text-align: left; padding: 8px; border: 1px solid #28a745;">→</th><th style="text-align: left; padding: 8px; border: 1px solid #28a745;">Transformed</th></tr>';
    
    samples.forEach(function(comment) {
        var original = comment || '(empty)';
        var transformed = comment.replace(regex, replacement);
        var changed = original !== transformed;
        
        previewHtml += '<tr>';
        previewHtml += '<td style="padding: 8px; border: 1px solid #ddd; font-family: monospace;">' + original + '</td>';
        previewHtml += '<td style="padding: 8px; border: 1px solid #ddd; text-align: center;">→</td>';
        previewHtml += '<td style="padding: 8px; border: 1px solid #ddd; font-family: monospace;' + (changed ? ' font-weight: bold; color: #28a745; background-color: rgba(40, 167, 69, 0.1);' : '') + '">' + transformed + '</td>';
        previewHtml += '</tr>';
    });
    
    previewHtml += '</table></div>';
    
    document.querySelector('.regex-help').insertAdjacentHTML('afterend', previewHtml);
}

function showRegexError(message) {
    var errorHtml = '<div id="regex-preview" style="margin-top: 15px; padding: 15px; background-color: #f8d7da; border-radius: 5px; border-left: 4px solid #dc3545;">';
    errorHtml += '<h5 style="margin-top: 0; color: #dc3545;">❌ Error:</h5>';
    errorHtml += '<p style="margin: 0; color: #721c24; font-weight: bold;">' + message + '</p>';
    errorHtml += '</div>';
    
    document.querySelector('.regex-help').insertAdjacentHTML('afterend', errorHtml);
}

// Form submission confirmation
document.getElementById('move-clients-form').addEventListener('submit', function(e) {
    var checkboxes = document.getElementsByName('selected_links');
    var selectedCount = 0;
    var selectedUsers = new Set();
    
    for (var i = 0; i < checkboxes.length; i++) {
        if (checkboxes[i].checked) {
            selectedCount++;
            selectedUsers.add(checkboxes[i].getAttribute('data-username'));
        }
    }
    
    var sourceServerName = document.getElementById('source_server').selectedOptions[0].text;
    var targetServerName = document.getElementById('target_server').selectedOptions[0].text;
    var commentRegex = document.getElementById('comment_regex').value.trim();
    
    var confirmMessage = 'Are you sure you want to move ' + selectedCount + ' link(s) for ' + selectedUsers.size + ' user(s) from "' + sourceServerName + '" to "' + targetServerName + '"?\n\n';
    confirmMessage += 'This action will:\n';
    confirmMessage += '- Transfer selected links to target server\n';
    confirmMessage += '- Create ACLs for users who don\'t have access to target server\n';
    confirmMessage += '- Remove empty ACLs from source server\n';
    confirmMessage += '- Preserve all link settings and comments\n';
    
    if (commentRegex) {
        confirmMessage += '- Apply regex transformation to comments: "' + commentRegex + '"\n';
    }
    
    confirmMessage += '\nThis cannot be undone.';
    
    if (!confirm(confirmMessage)) {
        e.preventDefault();
    }
});
</script>

<style>
.alert {
    margin: 10px 0;
    padding: 10px;
    border-radius: 4px;
}

.form-row {
    margin-bottom: 20px;
}

.submit-row {
    padding: 12px 14px;
    margin: 0 0 20px;
    background: #f8f8f8;
    border: 1px solid #ddd;
    border-radius: 4px;
}

.submit-row input[type="submit"] {
    background: #417690;
    color: white;
    border: none;
    padding: 10px 15px;
    border-radius: 4px;
    cursor: pointer;
    margin-right: 10px;
}

.submit-row input[type="submit"]:disabled {
    background: #ccc;
    cursor: not-allowed;
}

.submit-row .cancel {
    background: #6c757d;
    color: white;
    padding: 10px 15px;
    border-radius: 4px;
    text-decoration: none;
}

.submit-row .cancel:hover {
    background: #5a6268;
    color: white;
}

.link-row:hover {
    background-color: #f8f9fa;
}

input[type="checkbox"]:indeterminate {
    opacity: 0.5;
}

#comment_regex {
    transition: border-color 0.3s ease;
}

#comment_regex:focus {
    border-color: #007cba !important;
    box-shadow: 0 0 5px rgba(0, 124, 186, 0.3);
}
</style>
{% endblock %}