@page "/design/templates/{Id:int}"
@using ScadaLink.Security
@using ScadaLink.Commons.Entities.Templates
@using ScadaLink.Commons.Interfaces.Repositories
@using ScadaLink.Commons.Types.Enums
@using ScadaLink.TemplateEngine
@using ScadaLink.TemplateEngine.Services
@using ScadaLink.TemplateEngine.Validation
@attribute [Authorize(Policy = AuthorizationPolicies.RequireDesign)]
@inject ITemplateEngineRepository TemplateEngineRepository
@inject TemplateService TemplateService
@inject AuthenticationStateProvider AuthStateProvider
@inject NavigationManager NavigationManager

<div class="container-fluid mt-3">
    <ToastNotification @ref="_toast" />
    <ConfirmDialog @ref="_confirmDialog" ConfirmButtonClass="btn-danger" />

    <div class="mb-3">
        <button class="btn btn-outline-secondary btn-sm"
                aria-label="Back to Templates"
                @onclick="GoBack">← Templates</button>
    </div>

    @if (_loading)
    {
        <LoadingSpinner IsLoading="true" />
    }
    else if (_loadError != null)
    {
        <div class="alert alert-danger">@_loadError</div>
    }
    else if (_selectedTemplate == null)
    {
        <div class="alert alert-warning">Template not found.</div>
    }
    else
    {
        @RenderTemplateDetail()
    }
</div>

@code {
    [Parameter] public int Id { get; set; }

    private List<Template> _templates = new();
    private Template? _selectedTemplate;
    private List<TemplateAttribute> _attributes = new();
    private List<TemplateAlarm> _alarms = new();
    private List<TemplateScript> _scripts = new();
    private List<TemplateComposition> _compositions = new();

    private bool _loading = true;
    private string? _loadError;
    private string _activeTab = "attributes";

    // Edit properties
    private string _editName = string.Empty;
    private string? _editDescription;
    private int _editParentId;

    // Validation
    private bool _validating;
    private Commons.Types.Flattening.ValidationResult? _validationResult;

    // Member add forms
    private bool _showAttrForm;
    private string _attrName = string.Empty;
    private string? _attrValue;
    private DataType _attrDataType;
    private bool _attrIsLocked;
    private string? _attrDataSourceRef;
    private string? _attrFormError;

    private bool _showAlarmForm;
    private string _alarmName = string.Empty;
    private int _alarmPriority;
    private AlarmTriggerType _alarmTriggerType;
    private string? _alarmTriggerConfig;
    private bool _alarmIsLocked;
    private string? _alarmFormError;

    private bool _showScriptForm;
    private string _scriptName = string.Empty;
    private string _scriptCode = string.Empty;
    private string? _scriptTriggerType;
    private string? _scriptTriggerConfig;
    private bool _scriptIsLocked;
    private string? _scriptFormError;

    private bool _showCompForm;
    private int _compComposedTemplateId;
    private string _compInstanceName = string.Empty;
    private string? _compFormError;

    private ToastNotification _toast = default!;
    private ConfirmDialog _confirmDialog = default!;

    protected override async Task OnParametersSetAsync()
    {
        await LoadAsync();
    }

    private async Task LoadAsync()
    {
        _loading = true;
        _loadError = null;
        try
        {
            _templates = (await TemplateEngineRepository.GetAllTemplatesAsync()).ToList();

            _selectedTemplate = await TemplateEngineRepository.GetTemplateWithChildrenAsync(Id)
                                ?? _templates.FirstOrDefault(t => t.Id == Id);
            if (_selectedTemplate == null) { _loading = false; return; }

            _editName = _selectedTemplate.Name;
            _editDescription = _selectedTemplate.Description;
            _editParentId = _selectedTemplate.ParentTemplateId ?? 0;

            _attributes = (await TemplateEngineRepository.GetAttributesByTemplateIdAsync(Id)).ToList();
            _alarms = (await TemplateEngineRepository.GetAlarmsByTemplateIdAsync(Id)).ToList();
            _scripts = (await TemplateEngineRepository.GetScriptsByTemplateIdAsync(Id)).ToList();
            _compositions = (await TemplateEngineRepository.GetCompositionsByTemplateIdAsync(Id)).ToList();

            _validationResult = null;
        }
        catch (Exception ex)
        {
            _loadError = $"Failed to load template: {ex.Message}";
        }
        _loading = false;
    }

    private void GoBack()
    {
        NavigationManager.NavigateTo("/design/templates");
    }

    private async Task<string> GetCurrentUserAsync()
    {
        var authState = await AuthStateProvider.GetAuthenticationStateAsync();
        return authState.User.FindFirst("Username")?.Value ?? "unknown";
    }

    private RenderFragment RenderTemplateDetail() => __builder =>
    {
        <div class="d-flex justify-content-between align-items-center mb-3">
            <div>
                <h4 class="d-inline mb-0">@_selectedTemplate!.Name</h4>
                @if (_selectedTemplate.ParentTemplateId.HasValue)
                {
                    <span class="text-muted ms-2">inherits @(_templates.FirstOrDefault(t => t.Id == _selectedTemplate.ParentTemplateId)?.Name)</span>
                }
            </div>
            <div>
                <button class="btn btn-outline-info btn-sm me-1" @onclick="RunValidation" disabled="@_validating">
                    @if (_validating)
                    {
                        <span class="spinner-border spinner-border-sm me-1"></span>
                    }
                    Validate
                </button>
                <button class="btn btn-outline-danger btn-sm" @onclick="DeleteTemplate">Delete</button>
            </div>
        </div>

        @* Validation results *@
        @if (_validationResult != null)
        {
            <div class="mb-3">
                @if (_validationResult.Errors.Count > 0)
                {
                    <div class="alert alert-danger py-2">
                        <strong>Validation Errors (@_validationResult.Errors.Count)</strong>
                        <ul class="mb-0 small">
                            @foreach (var err in _validationResult.Errors)
                            {
                                <li class="mb-1">
                                    <strong>@err.Category</strong> @err.Message
                                    @if (err.EntityName != null)
                                    {
                                        <span class="text-muted">(@err.EntityName)</span>
                                    }
                                </li>
                            }
                        </ul>
                    </div>
                }
                @if (_validationResult.Warnings.Count > 0)
                {
                    <div class="alert alert-warning py-2">
                        <strong>Warnings (@_validationResult.Warnings.Count)</strong>
                        <ul class="mb-0 small">
                            @foreach (var warn in _validationResult.Warnings)
                            {
                                <li class="mb-1">
                                    <strong>@warn.Category</strong> <span class="text-muted">@warn.Message</span>
                                </li>
                            }
                        </ul>
                    </div>
                }
                @if (_validationResult.Errors.Count == 0 && _validationResult.Warnings.Count == 0)
                {
                    <div class="alert alert-success py-2">Validation passed with no errors or warnings.</div>
                }
            </div>
        }

        @* Template info edit *@
        <div class="card mb-3">
            <div class="card-header">Template Properties</div>
            <div class="card-body">
                <div class="row g-3">
                    <div class="col-12">
                        <label class="form-label">Name</label>
                        <input type="text" class="form-control" @bind="_editName" />
                    </div>
                    <div class="col-12">
                        <label class="form-label">Description</label>
                        <input type="text" class="form-control" @bind="_editDescription" />
                    </div>
                    <div class="col-12">
                        <label class="form-label">Parent Template</label>
                        <input type="text" readonly class="form-control form-control-plaintext"
                               value="@(_selectedTemplate.ParentTemplateId is int pid
                                        ? _templates.FirstOrDefault(t => t.Id == pid)?.Name ?? $"#{pid}"
                                        : "(none)")" />
                    </div>
                    <div class="col-12 text-end">
                        <button class="btn btn-primary" @onclick="UpdateTemplateProperties">Save Properties</button>
                    </div>
                </div>
            </div>
        </div>

        @* Tabs: Attributes, Alarms, Scripts, Compositions *@
        <ul class="nav nav-tabs mb-3" role="tablist">
            <li class="nav-item" role="presentation">
                <button class="nav-link @(_activeTab == "attributes" ? "active" : "")"
                        role="tab"
                        aria-selected="@(_activeTab == "attributes" ? "true" : "false")"
                        aria-controls="tmpl-tab-attributes"
                        @onclick='() => _activeTab = "attributes"'>
                    Attributes <span class="badge bg-secondary">@_attributes.Count</span>
                </button>
            </li>
            <li class="nav-item" role="presentation">
                <button class="nav-link @(_activeTab == "alarms" ? "active" : "")"
                        role="tab"
                        aria-selected="@(_activeTab == "alarms" ? "true" : "false")"
                        aria-controls="tmpl-tab-alarms"
                        @onclick='() => _activeTab = "alarms"'>
                    Alarms <span class="badge bg-secondary">@_alarms.Count</span>
                </button>
            </li>
            <li class="nav-item" role="presentation">
                <button class="nav-link @(_activeTab == "scripts" ? "active" : "")"
                        role="tab"
                        aria-selected="@(_activeTab == "scripts" ? "true" : "false")"
                        aria-controls="tmpl-tab-scripts"
                        @onclick='() => _activeTab = "scripts"'>
                    Scripts <span class="badge bg-secondary">@_scripts.Count</span>
                </button>
            </li>
            <li class="nav-item" role="presentation">
                <button class="nav-link @(_activeTab == "compositions" ? "active" : "")"
                        role="tab"
                        aria-selected="@(_activeTab == "compositions" ? "true" : "false")"
                        aria-controls="tmpl-tab-compositions"
                        @onclick='() => _activeTab = "compositions"'>
                    Compositions <span class="badge bg-secondary">@_compositions.Count</span>
                </button>
            </li>
        </ul>

        @if (_activeTab == "attributes")
        {
            <div role="tabpanel" id="tmpl-tab-attributes">@RenderAttributesTab()</div>
        }
        else if (_activeTab == "alarms")
        {
            <div role="tabpanel" id="tmpl-tab-alarms">@RenderAlarmsTab()</div>
        }
        else if (_activeTab == "scripts")
        {
            <div role="tabpanel" id="tmpl-tab-scripts">@RenderScriptsTab()</div>
        }
        else if (_activeTab == "compositions")
        {
            <div role="tabpanel" id="tmpl-tab-compositions">@RenderCompositionsTab()</div>
        }
    };

    private async Task DeleteTemplate()
    {
        if (_selectedTemplate == null) return;
        var confirmed = await _confirmDialog.ShowAsync(
            $"Delete template '{_selectedTemplate.Name}'? This will fail if instances or child templates reference it.",
            "Delete Template");
        if (!confirmed) return;

        try
        {
            var user = await GetCurrentUserAsync();
            var result = await TemplateService.DeleteTemplateAsync(_selectedTemplate.Id, user);
            if (result.IsSuccess)
            {
                _toast.ShowSuccess($"Template '{_selectedTemplate.Name}' deleted.");
                NavigationManager.NavigateTo("/design/templates");
            }
            else
            {
                _toast.ShowError(result.Error);
            }
        }
        catch (Exception ex)
        {
            _toast.ShowError($"Delete failed: {ex.Message}");
        }
    }

    private async Task UpdateTemplateProperties()
    {
        if (_selectedTemplate == null) return;
        try
        {
            var user = await GetCurrentUserAsync();
            var result = await TemplateService.UpdateTemplateAsync(
                _selectedTemplate.Id, _editName.Trim(), _editDescription?.Trim(),
                _editParentId == 0 ? null : _editParentId, user);

            if (result.IsSuccess)
            {
                _toast.ShowSuccess("Template properties updated.");
                _selectedTemplate = result.Value;
            }
            else
            {
                _toast.ShowError(result.Error);
            }
        }
        catch (Exception ex)
        {
            _toast.ShowError($"Update failed: {ex.Message}");
        }
    }

    private async Task RunValidation()
    {
        if (_selectedTemplate == null) return;
        _validating = true;
        _validationResult = null;
        try
        {
            var validationService = new ValidationService();
            var flatConfig = new Commons.Types.Flattening.FlattenedConfiguration
            {
                InstanceUniqueName = $"validation-{_selectedTemplate.Name}",
                TemplateId = _selectedTemplate.Id,
                Attributes = _attributes.Select(a => new Commons.Types.Flattening.ResolvedAttribute
                {
                    CanonicalName = a.Name,
                    Value = a.Value,
                    DataType = a.DataType.ToString(),
                    IsLocked = a.IsLocked,
                    DataSourceReference = a.DataSourceReference
                }).ToList(),
                Alarms = _alarms.Select(a => new Commons.Types.Flattening.ResolvedAlarm
                {
                    CanonicalName = a.Name,
                    PriorityLevel = a.PriorityLevel,
                    IsLocked = a.IsLocked,
                    TriggerType = a.TriggerType.ToString(),
                    TriggerConfiguration = a.TriggerConfiguration
                }).ToList(),
                Scripts = _scripts.Select(s => new Commons.Types.Flattening.ResolvedScript
                {
                    CanonicalName = s.Name,
                    Code = s.Code,
                    IsLocked = s.IsLocked,
                    TriggerType = s.TriggerType,
                    TriggerConfiguration = s.TriggerConfiguration,
                    ParameterDefinitions = s.ParameterDefinitions,
                    ReturnDefinition = s.ReturnDefinition
                }).ToList()
            };
            _validationResult = validationService.Validate(flatConfig);

            var collisions = await TemplateService.DetectCollisionsAsync(_selectedTemplate.Id);
            if (collisions.Count > 0)
            {
                var collisionErrors = collisions.Select(c =>
                    Commons.Types.Flattening.ValidationEntry.Error(
                        Commons.Types.Flattening.ValidationCategory.NamingCollision, c)).ToArray();
                var collisionResult = new Commons.Types.Flattening.ValidationResult { Errors = collisionErrors };
                _validationResult = Commons.Types.Flattening.ValidationResult.Merge(_validationResult, collisionResult);
            }
        }
        catch (Exception ex)
        {
            _toast.ShowError($"Validation error: {ex.Message}");
        }
        _validating = false;
    }

    // ---- Attributes Tab ----
    private RenderFragment RenderAttributesTab() => __builder =>
    {
        <div class="d-flex justify-content-between align-items-center mb-2">
            <h5 class="mb-0">Attributes</h5>
            <button class="btn btn-primary btn-sm" @onclick="() => { _showAttrForm = true; _attrFormError = null; _attrName = string.Empty; _attrValue = null; _attrIsLocked = false; _attrDataSourceRef = null; }">Add Attribute</button>
        </div>

        @if (_showAttrForm)
        {
            <div class="card mb-3">
                <div class="card-header">Add Attribute</div>
                <div class="card-body">
                    <div class="row g-3">
                        <div class="col-12">
                            <label class="form-label">Name</label>
                            <input type="text" class="form-control" @bind="_attrName" />
                        </div>
                        <div class="col-12">
                            <label class="form-label">Data Type</label>
                            <select class="form-select" @bind="_attrDataType">
                                @foreach (var dt in Enum.GetValues<DataType>())
                                {
                                    <option value="@dt">@dt</option>
                                }
                            </select>
                        </div>
                        <div class="col-12">
                            <label class="form-label">Value</label>
                            <input type="text" class="form-control" @bind="_attrValue" />
                        </div>
                        <div class="col-12">
                            <label class="form-label">Data Source Ref</label>
                            <input type="text" class="form-control" @bind="_attrDataSourceRef" placeholder="Tag path" />
                        </div>
                        <div class="col-12">
                            <div class="form-check">
                                <input class="form-check-input" type="checkbox" @bind="_attrIsLocked" id="attrLocked" />
                                <label class="form-check-label" for="attrLocked">Locked</label>
                            </div>
                        </div>
                        @if (_attrFormError != null)
                        {
                            <div class="col-12"><div class="text-danger small">@_attrFormError</div></div>
                        }
                        <div class="col-12 text-end">
                            <button class="btn btn-outline-secondary me-1" @onclick="() => _showAttrForm = false">Cancel</button>
                            <button class="btn btn-success" @onclick="AddAttribute">Add</button>
                        </div>
                    </div>
                </div>
            </div>
        }

        <table class="table table-sm table-striped">
            <thead class="table-light">
                <tr>
                    <th>Name</th>
                    <th>Type</th>
                    <th>Value</th>
                    <th>Data Source</th>
                    <th>Lock</th>
                    <th style="width: 60px;">Actions</th>
                </tr>
            </thead>
            <tbody>
                @foreach (var attr in _attributes)
                {
                    <tr>
                        <td>@attr.Name</td>
                        <td><span class="badge bg-light text-dark">@attr.DataType</span></td>
                        <td class="small">@(attr.Value ?? "—")</td>
                        <td class="small text-muted">@(attr.DataSourceReference ?? "—")</td>
                        <td>
                            @if (attr.IsLocked)
                            {
                                <span class="badge bg-danger" aria-label="Locked">Locked</span>
                            }
                            else
                            {
                                <span class="badge bg-light text-dark" aria-label="Unlocked">Unlocked</span>
                            }
                        </td>
                        <td>
                            <div class="dropdown">
                                <button class="btn btn-outline-secondary btn-sm py-0 px-1"
                                        data-bs-toggle="dropdown"
                                        aria-expanded="false"
                                        aria-label="@($"More actions for {attr.Name}")">⋮</button>
                                <ul class="dropdown-menu dropdown-menu-end">
                                    <li>
                                        <button class="dropdown-item text-danger"
                                                @onclick="() => DeleteAttribute(attr)">Delete</button>
                                    </li>
                                </ul>
                            </div>
                        </td>
                    </tr>
                }
            </tbody>
        </table>
    };

    // ---- Alarms Tab ----
    private RenderFragment RenderAlarmsTab() => __builder =>
    {
        <div class="d-flex justify-content-between align-items-center mb-2">
            <h5 class="mb-0">Alarms</h5>
            <button class="btn btn-primary btn-sm" @onclick="() => { _showAlarmForm = true; _alarmFormError = null; _alarmName = string.Empty; _alarmPriority = 500; _alarmTriggerConfig = null; _alarmIsLocked = false; }">Add Alarm</button>
        </div>

        @if (_showAlarmForm)
        {
            <div class="card mb-3">
                <div class="card-header">Add Alarm</div>
                <div class="card-body">
                    <div class="row g-3">
                        <div class="col-12">
                            <label class="form-label">Name</label>
                            <input type="text" class="form-control" @bind="_alarmName" />
                        </div>
                        <div class="col-12">
                            <label class="form-label">Trigger Type</label>
                            <select class="form-select" @bind="_alarmTriggerType">
                                @foreach (var tt in Enum.GetValues<AlarmTriggerType>())
                                {
                                    <option value="@tt">@tt</option>
                                }
                            </select>
                        </div>
                        <div class="col-12">
                            <label class="form-label">Priority</label>
                            <input type="number" class="form-control" @bind="_alarmPriority" min="0" max="1000" />
                        </div>
                        <div class="col-12">
                            <label class="form-label">Trigger Config (JSON)</label>
                            <input type="text" class="form-control" @bind="_alarmTriggerConfig" />
                        </div>
                        <div class="col-12">
                            <div class="form-check">
                                <input class="form-check-input" type="checkbox" @bind="_alarmIsLocked" id="alarmLocked" />
                                <label class="form-check-label" for="alarmLocked">Locked</label>
                            </div>
                        </div>
                        @if (_alarmFormError != null)
                        {
                            <div class="col-12"><div class="text-danger small">@_alarmFormError</div></div>
                        }
                        <div class="col-12 text-end">
                            <button class="btn btn-outline-secondary me-1" @onclick="() => _showAlarmForm = false">Cancel</button>
                            <button class="btn btn-success" @onclick="AddAlarm">Add</button>
                        </div>
                    </div>
                </div>
            </div>
        }

        <table class="table table-sm table-striped">
            <thead class="table-light">
                <tr>
                    <th>Name</th>
                    <th>Trigger</th>
                    <th>Priority</th>
                    <th>Config</th>
                    <th>Lock</th>
                    <th style="width: 60px;">Actions</th>
                </tr>
            </thead>
            <tbody>
                @foreach (var alarm in _alarms)
                {
                    <tr>
                        <td>@alarm.Name</td>
                        <td><span class="badge bg-light text-dark">@alarm.TriggerType</span></td>
                        <td>@alarm.PriorityLevel</td>
                        <td class="small text-muted text-truncate" style="max-width: 200px;">@(alarm.TriggerConfiguration ?? "—")</td>
                        <td>
                            @if (alarm.IsLocked)
                            {
                                <span class="badge bg-danger" aria-label="Locked">Locked</span>
                            }
                            else
                            {
                                <span class="badge bg-light text-dark" aria-label="Unlocked">Unlocked</span>
                            }
                        </td>
                        <td>
                            <div class="dropdown">
                                <button class="btn btn-outline-secondary btn-sm py-0 px-1"
                                        data-bs-toggle="dropdown"
                                        aria-expanded="false"
                                        aria-label="@($"More actions for {alarm.Name}")">⋮</button>
                                <ul class="dropdown-menu dropdown-menu-end">
                                    <li>
                                        <button class="dropdown-item text-danger"
                                                @onclick="() => DeleteAlarm(alarm)">Delete</button>
                                    </li>
                                </ul>
                            </div>
                        </td>
                    </tr>
                }
            </tbody>
        </table>
    };

    // ---- Scripts Tab ----
    private RenderFragment RenderScriptsTab() => __builder =>
    {
        <div class="d-flex justify-content-between align-items-center mb-2">
            <h5 class="mb-0">Scripts</h5>
            <button class="btn btn-primary btn-sm" @onclick="() => { _showScriptForm = true; _scriptFormError = null; _scriptName = string.Empty; _scriptCode = string.Empty; _scriptTriggerType = null; _scriptTriggerConfig = null; _scriptIsLocked = false; }">Add Script</button>
        </div>

        @if (_showScriptForm)
        {
            <div class="card mb-3">
                <div class="card-header">Add Script</div>
                <div class="card-body">
                    <div class="row g-3">
                        <div class="col-12">
                            <label class="form-label">Name</label>
                            <input type="text" class="form-control" @bind="_scriptName" />
                        </div>
                        <div class="col-12">
                            <label class="form-label">Trigger Type</label>
                            <input type="text" class="form-control" @bind="_scriptTriggerType" placeholder="e.g. ValueChange" />
                        </div>
                        <div class="col-12">
                            <label class="form-label">Trigger Config (JSON)</label>
                            <input type="text" class="form-control" @bind="_scriptTriggerConfig" />
                        </div>
                        <div class="col-12">
                            <div class="form-check">
                                <input class="form-check-input" type="checkbox" @bind="_scriptIsLocked" id="scriptLocked" />
                                <label class="form-check-label" for="scriptLocked">Locked</label>
                            </div>
                        </div>
                        <div class="col-12">
                            <label class="form-label">Code</label>
                            <textarea class="form-control font-monospace" rows="10" @bind="_scriptCode"
                                      style="font-size: 0.85rem;"></textarea>
                        </div>
                        @if (_scriptFormError != null)
                        {
                            <div class="col-12"><div class="text-danger small">@_scriptFormError</div></div>
                        }
                        <div class="col-12 text-end">
                            <button class="btn btn-outline-secondary me-1" @onclick="() => _showScriptForm = false">Cancel</button>
                            <button class="btn btn-success" @onclick="AddScript">Add</button>
                        </div>
                    </div>
                </div>
            </div>
        }

        <table class="table table-sm table-striped">
            <thead class="table-light">
                <tr>
                    <th>Name</th>
                    <th>Trigger</th>
                    <th>Code (preview)</th>
                    <th>Lock</th>
                    <th style="width: 60px;">Actions</th>
                </tr>
            </thead>
            <tbody>
                @foreach (var script in _scripts)
                {
                    <tr>
                        <td>@script.Name</td>
                        <td class="small">@(script.TriggerType ?? "—")</td>
                        <td class="small text-muted text-truncate font-monospace"
                            style="max-width: 300px;"
                            title="@script.Code">@script.Code[..Math.Min(80, script.Code.Length)]@(script.Code.Length > 80 ? "..." : "")</td>
                        <td>
                            @if (script.IsLocked)
                            {
                                <span class="badge bg-danger" aria-label="Locked">Locked</span>
                            }
                            else
                            {
                                <span class="badge bg-light text-dark" aria-label="Unlocked">Unlocked</span>
                            }
                        </td>
                        <td>
                            <div class="dropdown">
                                <button class="btn btn-outline-secondary btn-sm py-0 px-1"
                                        data-bs-toggle="dropdown"
                                        aria-expanded="false"
                                        aria-label="@($"More actions for {script.Name}")">⋮</button>
                                <ul class="dropdown-menu dropdown-menu-end">
                                    <li>
                                        <button class="dropdown-item text-danger"
                                                @onclick="() => DeleteScript(script)">Delete</button>
                                    </li>
                                </ul>
                            </div>
                        </td>
                    </tr>
                }
            </tbody>
        </table>
    };

    // ---- Compositions Tab ----
    private RenderFragment RenderCompositionsTab() => __builder =>
    {
        <div class="d-flex justify-content-between align-items-center mb-2">
            <h5 class="mb-0">Compositions</h5>
            <button class="btn btn-primary btn-sm" @onclick="() => { _showCompForm = true; _compFormError = null; _compInstanceName = string.Empty; _compComposedTemplateId = 0; }">Add Composition</button>
        </div>

        @if (_showCompForm)
        {
            <div class="card mb-3">
                <div class="card-header">Add Composition</div>
                <div class="card-body">
                    <div class="row g-3">
                        <div class="col-12">
                            <label class="form-label">Instance Name</label>
                            <input type="text" class="form-control" @bind="_compInstanceName" />
                        </div>
                        <div class="col-12">
                            <label class="form-label">Composed Template</label>
                            <select class="form-select" @bind="_compComposedTemplateId">
                                <option value="0">Select template...</option>
                                @foreach (var t in _templates.Where(t => _selectedTemplate == null || t.Id != _selectedTemplate.Id))
                                {
                                    <option value="@t.Id">@t.Name</option>
                                }
                            </select>
                        </div>
                        @if (_compFormError != null)
                        {
                            <div class="col-12"><div class="text-danger small">@_compFormError</div></div>
                        }
                        <div class="col-12 text-end">
                            <button class="btn btn-outline-secondary me-1" @onclick="() => _showCompForm = false">Cancel</button>
                            <button class="btn btn-success" @onclick="AddComposition">Add</button>
                        </div>
                    </div>
                </div>
            </div>
        }

        <table class="table table-sm table-striped">
            <thead class="table-light">
                <tr>
                    <th>Instance Name</th>
                    <th>Composed Template</th>
                    <th style="width: 60px;">Actions</th>
                </tr>
            </thead>
            <tbody>
                @foreach (var comp in _compositions)
                {
                    <tr>
                        <td><code>@comp.InstanceName</code></td>
                        <td>@(_templates.FirstOrDefault(t => t.Id == comp.ComposedTemplateId)?.Name ?? $"#{comp.ComposedTemplateId}")</td>
                        <td>
                            <div class="dropdown">
                                <button class="btn btn-outline-secondary btn-sm py-0 px-1"
                                        data-bs-toggle="dropdown"
                                        aria-expanded="false"
                                        aria-label="@($"More actions for {comp.InstanceName}")">⋮</button>
                                <ul class="dropdown-menu dropdown-menu-end">
                                    <li>
                                        <button class="dropdown-item text-danger"
                                                @onclick="() => DeleteComposition(comp)">Delete</button>
                                    </li>
                                </ul>
                            </div>
                        </td>
                    </tr>
                }
            </tbody>
        </table>
    };

    // ---- CRUD handlers ----

    private async Task AddAttribute()
    {
        if (_selectedTemplate == null) return;
        _attrFormError = null;
        if (string.IsNullOrWhiteSpace(_attrName)) { _attrFormError = "Name is required."; return; }

        var attr = new TemplateAttribute(_attrName.Trim())
        {
            DataType = _attrDataType,
            Value = _attrValue?.Trim(),
            IsLocked = _attrIsLocked,
            DataSourceReference = _attrDataSourceRef?.Trim()
        };

        var user = await GetCurrentUserAsync();
        var result = await TemplateService.AddAttributeAsync(_selectedTemplate.Id, attr, user);
        if (result.IsSuccess)
        {
            _showAttrForm = false;
            _toast.ShowSuccess($"Attribute '{_attrName}' added.");
            await LoadAsync();
        }
        else
        {
            _attrFormError = result.Error;
        }
    }

    private async Task DeleteAttribute(TemplateAttribute attr)
    {
        var confirmed = await _confirmDialog.ShowAsync($"Delete attribute '{attr.Name}'?", "Delete Attribute");
        if (!confirmed) return;
        var user = await GetCurrentUserAsync();
        var result = await TemplateService.DeleteAttributeAsync(attr.Id, user);
        if (result.IsSuccess)
        {
            _toast.ShowSuccess($"Attribute '{attr.Name}' deleted.");
            await LoadAsync();
        }
        else
        {
            _toast.ShowError(result.Error);
        }
    }

    private async Task AddAlarm()
    {
        if (_selectedTemplate == null) return;
        _alarmFormError = null;
        if (string.IsNullOrWhiteSpace(_alarmName)) { _alarmFormError = "Name is required."; return; }

        var alarm = new TemplateAlarm(_alarmName.Trim())
        {
            TriggerType = _alarmTriggerType,
            PriorityLevel = _alarmPriority,
            TriggerConfiguration = _alarmTriggerConfig?.Trim(),
            IsLocked = _alarmIsLocked
        };

        var user = await GetCurrentUserAsync();
        var result = await TemplateService.AddAlarmAsync(_selectedTemplate.Id, alarm, user);
        if (result.IsSuccess)
        {
            _showAlarmForm = false;
            _toast.ShowSuccess($"Alarm '{_alarmName}' added.");
            await LoadAsync();
        }
        else
        {
            _alarmFormError = result.Error;
        }
    }

    private async Task DeleteAlarm(TemplateAlarm alarm)
    {
        var confirmed = await _confirmDialog.ShowAsync($"Delete alarm '{alarm.Name}'?", "Delete Alarm");
        if (!confirmed) return;
        var user = await GetCurrentUserAsync();
        var result = await TemplateService.DeleteAlarmAsync(alarm.Id, user);
        if (result.IsSuccess)
        {
            _toast.ShowSuccess($"Alarm '{alarm.Name}' deleted.");
            await LoadAsync();
        }
        else { _toast.ShowError(result.Error); }
    }

    private async Task AddScript()
    {
        if (_selectedTemplate == null) return;
        _scriptFormError = null;
        if (string.IsNullOrWhiteSpace(_scriptName)) { _scriptFormError = "Name is required."; return; }
        if (string.IsNullOrWhiteSpace(_scriptCode)) { _scriptFormError = "Code is required."; return; }

        var script = new TemplateScript(_scriptName.Trim(), _scriptCode)
        {
            TriggerType = _scriptTriggerType?.Trim(),
            TriggerConfiguration = _scriptTriggerConfig?.Trim(),
            IsLocked = _scriptIsLocked
        };

        var user = await GetCurrentUserAsync();
        var result = await TemplateService.AddScriptAsync(_selectedTemplate.Id, script, user);
        if (result.IsSuccess)
        {
            _showScriptForm = false;
            _toast.ShowSuccess($"Script '{_scriptName}' added.");
            await LoadAsync();
        }
        else
        {
            _scriptFormError = result.Error;
        }
    }

    private async Task DeleteScript(TemplateScript script)
    {
        var confirmed = await _confirmDialog.ShowAsync($"Delete script '{script.Name}'?", "Delete Script");
        if (!confirmed) return;
        var user = await GetCurrentUserAsync();
        var result = await TemplateService.DeleteScriptAsync(script.Id, user);
        if (result.IsSuccess)
        {
            _toast.ShowSuccess($"Script '{script.Name}' deleted.");
            await LoadAsync();
        }
        else { _toast.ShowError(result.Error); }
    }

    private async Task AddComposition()
    {
        if (_selectedTemplate == null) return;
        _compFormError = null;
        if (string.IsNullOrWhiteSpace(_compInstanceName)) { _compFormError = "Instance name is required."; return; }
        if (_compComposedTemplateId == 0) { _compFormError = "Select a template."; return; }

        var user = await GetCurrentUserAsync();
        var result = await TemplateService.AddCompositionAsync(
            _selectedTemplate.Id, _compComposedTemplateId, _compInstanceName.Trim(), user);
        if (result.IsSuccess)
        {
            _showCompForm = false;
            _toast.ShowSuccess($"Composition '{_compInstanceName}' added.");
            await LoadAsync();
        }
        else
        {
            _compFormError = result.Error;
        }
    }

    private async Task DeleteComposition(TemplateComposition comp)
    {
        var confirmed = await _confirmDialog.ShowAsync($"Remove composition '{comp.InstanceName}'?", "Delete Composition");
        if (!confirmed) return;
        var user = await GetCurrentUserAsync();
        var result = await TemplateService.DeleteCompositionAsync(comp.Id, user);
        if (result.IsSuccess)
        {
            _toast.ShowSuccess($"Composition '{comp.InstanceName}' removed.");
            await LoadAsync();
        }
        else { _toast.ShowError(result.Error); }
    }
}