@using Microsoft.Extensions.DependencyInjection
@inject IServiceProvider MutationServices
@page "/deployment/instances/create"
@using ZB.MOM.WW.ScadaBridge.Security
@using ZB.MOM.WW.ScadaBridge.Commons.Entities.Instances
@using ZB.MOM.WW.ScadaBridge.Commons.Entities.Sites
@using ZB.MOM.WW.ScadaBridge.Commons.Entities.Templates
@using ZB.MOM.WW.ScadaBridge.Commons.Interfaces.Protocol
@using ZB.MOM.WW.ScadaBridge.Commons.Interfaces.Repositories
@using ZB.MOM.WW.ScadaBridge.Commons.Messages.Management
@using ZB.MOM.WW.ScadaBridge.TemplateEngine.Services
@using ZB.MOM.WW.ScadaBridge.DeploymentManager
@using ZB.MOM.WW.ScadaBridge.CentralUI.Components.Dialogs
@using ZB.MOM.WW.ScadaBridge.CentralUI.Components.Shared
@using ZB.MOM.WW.ScadaBridge.CentralUI.Services
@attribute [Authorize(Policy = AuthorizationPolicies.RequireDeployment)]
@inject ITemplateEngineRepository TemplateEngineRepository
@inject ISiteRepository SiteRepository
@inject ZB.MOM.WW.ScadaBridge.CentralUI.Auth.SiteScopeService SiteScope
@inject InstanceService InstanceService
@inject IFlatteningPipeline FlatteningPipeline
@inject AuthenticationStateProvider AuthStateProvider
@inject NavigationManager NavigationManager
@inject IDialogService Dialog

<div class="container-fluid mt-3">
    <div class="d-flex align-items-center mb-3">
        <a href="/deployment/topology" class="btn btn-outline-secondary btn-sm me-3">&larr; Back</a>
        <h4 class="mb-0">Create Instance</h4>
    </div>

    @if (_loading)
    {
        <LoadingSpinner IsLoading="true" />
    }
    else
    {
        <div class="card mb-3">
            <div class="card-body">
                <div class="mb-2">
                    <label class="form-label small">Instance Name</label>
                    <input type="text" class="form-control form-control-sm" @bind="_createName" placeholder="e.g. Motor-1" />
                </div>
                <div class="mb-2">
                    <label class="form-label small">Template</label>
                    <div class="input-group input-group-sm">
                        <input type="text" class="form-control" data-test="create-template" readonly
                               placeholder="Choose a template…" value="@TemplatePathLabel"
                               style="cursor: pointer; background-color: var(--bs-body-bg);"
                               @onclick="OpenTemplatePickerAsync" />
                        <button class="btn btn-outline-secondary" type="button" data-test="create-template-choose"
                                disabled="@(_templates.Count == 0)" @onclick="OpenTemplatePickerAsync">Choose…</button>
                    </div>
                    @if (_templates.Count == 0)
                    {
                        <div class="form-text">No templates exist yet — <a href="/design/templates">create one on the Templates page</a>.</div>
                    }
                    else if (_templateHint is not null)
                    {
                        <div class="form-text text-warning-emphasis">@_templateHint</div>
                    }
                </div>
                <div class="mb-2">
                    <label class="form-label small">Site</label>
                    <select class="form-select form-select-sm" data-test="create-site"
                            value="@_createSiteId"
                            @onchange="async e => { _createSiteId = int.TryParse(e.Value?.ToString(), out var v) ? v : 0; _createAreaId = 0; await OnTemplateOrSiteChangedAsync(); }">
                        <option value="0">Select site...</option>
                        @foreach (var s in _sites)
                        {
                            <option value="@s.Id">@s.Name</option>
                        }
                    </select>
                </div>
                <div class="mb-2">
                    <label class="form-label small">Area</label>
                    <select class="form-select form-select-sm" @bind="_createAreaId">
                        <option value="0">No area</option>
                        @foreach (var a in _allAreas.Where(a => a.SiteId == _createSiteId))
                        {
                            <option value="@a.Id">@a.Name</option>
                        }
                    </select>
                </div>
                @if (_formError != null)
                {
                    <div class="text-danger small mt-2">@_formError</div>
                }
                @if (!BindingsCardVisible)
                {
                    <div class="btn-group btn-group-sm mt-3" role="group" aria-label="Create instance actions">
                        <button class="btn btn-success" @onclick="CreateInstance">Create</button>
                        <button class="btn btn-outline-secondary" @onclick="GoBack">Cancel</button>
                    </div>
                }
            </div>
        </div>

        @* Connection Bindings — the same module groups the Configure page shows, built
           from a template+site PREVIEW flatten (no instance row exists yet). Group
           headers only: per-member editing stays on Configure. Nothing is saved until
           Create. Design: docs/plans/2026-08-21-create-instance-bindings-design.md *@
        @if (BindingsCardVisible)
        {
            <div class="card mb-3" data-test="create-bindings-card">
                <div class="card-header py-2 d-flex align-items-center gap-3 flex-wrap">
                    <strong>Connection Bindings</strong>
                    @if (_previewLoading)
                    {
                        <span class="spinner-border spinner-border-sm" role="status"></span>
                    }
                    else
                    {
                        <span class="text-muted small">@_rowCount data-sourced attribute(s) in @_groups.Count group(s)</span>
                    }
                    <span class="ms-auto"></span>
                    @if (UnboundGroups > 0 && !_skipBindings)
                    {
                        <span class="badge text-bg-warning" data-test="create-unbound-groups">@UnboundGroups group(s) unbound</span>
                    }
                    <span class="badge border text-muted">preview — nothing saved yet</span>
                </div>
                @if (_previewError is not null)
                {
                    <div class="alert alert-warning rounded-0 mb-0 py-2 small" data-test="create-bindings-preview-error">
                        Could not preview this template at the selected site (@_previewError). You can create the instance and bind on Configure.
                    </div>
                }
                else if (!_previewLoading && _rowCount == 0)
                {
                    <div class="card-body text-muted small">Nothing to bind in this template.</div>
                }
                else if (_siteConnections.Count == 0)
                {
                    <div class="card-body text-muted small">This site has no data connections — add one under Sites, or create now and bind later.</div>
                }
                else if (!_skipBindings)
                {
                    <div class="card-body border-bottom py-2 d-flex align-items-center gap-2 flex-wrap small">
                        <span>Bind all to</span>
                        <select class="form-select form-select-sm" style="width: auto;" data-test="create-root-connection" @bind="_rootConnectionId">
                            <option value="0">Select connection...</option>
                            @foreach (var c in _siteConnections)
                            {
                                <option value="@c.Id">@c.Name (@c.Protocol)</option>
                            }
                        </select>
                        <input class="form-control form-control-sm font-monospace" style="max-width: 260px;" data-test="create-root-object"
                               @bind="_rootObject" placeholder="root object, e.g. Z28063" />
                        <button class="btn btn-outline-primary btn-sm" data-test="create-root-browse"
                                disabled="@(!IsBrowsable(_rootConnectionId))" @onclick="() => OpenBrowser(null)">Browse…</button>
                        <button class="btn btn-outline-primary btn-sm" data-test="create-prefill"
                                disabled="@(_rootConnectionId == 0)" @onclick="PrefillGroups">Prefill groups</button>
                        <span class="text-muted">Fills the connection on every group and suggests an Object for blanks; never overwrites an Object you typed.</span>
                    </div>
                    @foreach (var g in _groups)
                    {
                        var input = _inputs.GetValueOrDefault(g.Key);
                        var source = CreateBindingPlanner.SourceOf(g, input);
                        <div class="binding-group-header d-flex align-items-center gap-2 px-3 py-2 border-bottom" data-test="create-binding-group">
                            <span class="fw-semibold binding-group-name">@g.Key
                                @if (g.IsInstanceGroup)
                                {
                                    <small class="text-muted fw-normal ms-1">direct attributes</small>
                                }
                                else if (g.NestedModules.Count > 0)
                                {
                                    <small class="text-muted fw-normal ms-1">incl. @string.Join(", ", g.NestedModules)</small>
                                }
                            </span>
                            <span class="text-muted small">@g.Members.Count</span>
                            <select class="form-select form-select-sm" style="width: 160px;" data-test="create-group-connection"
                                    value="@(input?.ConnectionId ?? 0)"
                                    @onchange="e => SetGroupConnection(g, int.TryParse(e.Value?.ToString(), out var v) ? v : 0)">
                                <option value="0">— none —</option>
                                @foreach (var c in _siteConnections)
                                {
                                    <option value="@c.Id">@c.Name</option>
                                }
                            </select>
                            <input class="form-control form-control-sm font-monospace" style="max-width: 260px;" data-test="create-group-object"
                                   value="@input?.Object"
                                   placeholder="@(g.IsInstanceGroup ? "object, e.g. Z28063" : $"object, e.g. {g.Key}")"
                                   title="Object path this module's members hang off; every member binds as <object>.<member>."
                                   @onchange="e => SetGroupObject(g, e.Value?.ToString())" />
                            <button class="btn btn-outline-primary btn-sm" data-test="create-group-browse"
                                    disabled="@(!IsBrowsable(input?.ConnectionId ?? 0))" @onclick="() => OpenBrowser(g)">Browse…</button>
                            @if (source == CreateBindingPlanner.ObjectSource.Suggested)
                            {
                                <span class="badge text-bg-secondary" title="Suggested from the root object; edit if the object is a sibling">suggested</span>
                            }
                            else if (source == CreateBindingPlanner.ObjectSource.FromTemplate)
                            {
                                <span class="badge text-bg-secondary" title="The composed template's defaults already carry this object">from template</span>
                            }
                            @if (IsGroupBound(g))
                            {
                                <span class="badge text-bg-success">bound</span>
                            }
                            else
                            {
                                <span class="badge text-bg-danger">@g.Members.Count unbound</span>
                            }
                        </div>
                    }
                }
                <div class="card-footer d-flex align-items-center gap-2 flex-wrap">
                    <div class="btn-group btn-group-sm" role="group" aria-label="Create instance actions">
                        <button class="btn btn-success" @onclick="CreateInstance" disabled="@_previewLoading">Create instance</button>
                        <button class="btn btn-outline-secondary" @onclick="GoBack">Cancel</button>
                    </div>
                    <label class="form-check form-check-inline mb-0 small ms-2">
                        <input class="form-check-input" type="checkbox" data-test="create-skip-bindings" @bind="_skipBindings" />
                        Skip bindings — I'll bind on Configure
                    </label>
                    <span class="text-muted small ms-auto">
                        @if (_skipBindings)
                        {
                            <text>Creates the instance without bindings.</text>
                        }
                        else
                        {
                            <text>Creates the instance, saves @BoundRowCount binding(s), then opens Configure.@(UnboundGroups > 0 ? $" {UnboundGroups} group(s) stay unbound — Deploy is rejected until they are bound." : "")</text>
                        }
                    </span>
                </div>
            </div>

            @* Address-space picker. SelectableNodeClasses adds Object so a module's
               container node can be chosen, not just a leaf tag. *@
            <NodeBrowserDialog @ref="_browserRef"
                               SiteId="@(_siteIdentifier ?? "")"
                               ConnectionName="@_browserConnectionName"
                               InitialNodeId="@_browserInitial"
                               SelectableNodeClasses="ObjectAndVariable"
                               OnSelected="OnBrowserSelected" />
        }
    }
</div>

@code {
    /// <summary>Query preselect: the template the operator picked elsewhere (e.g. the Templates tree's "New Instance&#8230;").</summary>
    [SupplyParameterFromQuery] public int? TemplateId { get; set; }
    [SupplyParameterFromQuery] public int? SiteId { get; set; }
    [SupplyParameterFromQuery] public int? AreaId { get; set; }

    private List<Site> _sites = new();
    private List<Template> _templates = new();
    private List<TemplateFolder> _folders = new();
    private Dictionary<int, TemplateFolder> _foldersById = new();
    private string? _templateHint;

    /// <summary>Folder-qualified label shown in the read-only template field; blank when nothing is chosen.</summary>
    private string TemplatePathLabel => _templates.FirstOrDefault(t => t.Id == _createTemplateId) is { } t
        ? TemplatePathFormatter.Format(t, _foldersById)
        : string.Empty;
    private List<Area> _allAreas = new();
    private bool _loading = true;

    private string _createName = string.Empty;
    private int _createTemplateId;
    private int _createSiteId;
    private int _createAreaId;
    private string? _formError;

    protected override async Task OnInitializedAsync()
    {
        try
        {
            _templates = (await TemplateEngineRepository.GetTemplateStubsAsync()).ToShellTemplates();
            _folders = (await TemplateEngineRepository.GetAllFoldersAsync()).ToList();
            _foldersById = _folders.ToDictionary(f => f.Id);
            if (TemplateId is int tid)
            {
                if (_templates.Any(t => t.Id == tid)) _createTemplateId = tid;
                else _templateHint = $"Template {tid} no longer exists — choose another.";
            }
            // Site scoping (CentralUI-002): a scoped Deployment user may only
            // create instances on sites they are permitted on.
            _sites = await SiteScope.FilterSitesAsync(await SiteRepository.GetAllSitesAsync());

            _allAreas.Clear();
            foreach (var site in _sites)
            {
                var areas = await TemplateEngineRepository.GetAreasBySiteIdAsync(site.Id);
                _allAreas.AddRange(areas);
            }

            if (SiteId is int sid && _sites.Any(s => s.Id == sid))
            {
                _createSiteId = sid;
            }
            if (AreaId is int aid && _allAreas.Any(a => a.Id == aid && a.SiteId == _createSiteId))
            {
                _createAreaId = aid;
            }


            // Query-string preselects (siteId + templateId) make this a real preview
            // when both are present; it no-ops when either is missing.
            await OnTemplateOrSiteChangedAsync();
        }
        catch (Exception ex)
        {
            _formError = $"Failed to load data: {ex.Message}";
        }
        _loading = false;
    }

    private async Task CreateInstance()
    {
        _formError = null;
        if (string.IsNullOrWhiteSpace(_createName)) { _formError = "Instance name is required."; return; }
        if (_createTemplateId == 0) { _formError = "Select a template."; return; }
        if (_createSiteId == 0) { _formError = "Select a site."; return; }
        // Site scoping (CentralUI-002): re-check server-side before the mutating
        // command, independent of what the site dropdown was populated with.
        if (!await SiteScope.IsSiteAllowedAsync(_createSiteId))
        {
            _formError = "You are not permitted to create instances on the selected site.";
            return;
        }

        string user;
        int id;
        try
        {
            user = await GetCurrentUserAsync();
            var result = await MutationServices.GetRequiredService<ConfigurationCommandService>().ExecuteInstanceAsync(null, _createSiteId, (instanceService, currentUser) => instanceService.CreateInstanceAsync(
                _createName.Trim(), _createTemplateId, _createSiteId, _createAreaId == 0 ? null : _createAreaId, currentUser));
            if (result.IsFailure)
            {
                _formError = result.Error;
                return;
            }
            id = result.Value.Id;
        }
        catch (Exception ex)
        {
            _formError = $"Create failed: {ex.Message}";
            return;
        }

        // From here the instance EXISTS. Whatever the binding save does, land on
        // Configure rather than leaving the operator on a stale create form —
        // carrying any binding error in the query so it is visible there.
        var bindings = _skipBindings || _previewError is not null
            ? (IReadOnlyList<ConnectionBinding>)Array.Empty<ConnectionBinding>()
            : CreateBindingPlanner.BuildBindings(_groups, _inputs);

        if (bindings.Count == 0)
        {
            NavigationManager.NavigateTo($"/deployment/instances/{id}/configure?created=1");
            return;
        }

        string? bindError = null;
        try
        {
            var bind = await MutationServices.GetRequiredService<ConfigurationCommandService>().ExecuteInstanceAsync(id, null, (instanceService, currentUser) => instanceService.SetConnectionBindingsAsync(id, bindings, currentUser));
            if (bind.IsFailure) bindError = bind.Error;
        }
        catch (Exception ex)
        {
            // Network / actor timeout AFTER the instance was created.
            bindError = ex.Message;
        }

        var query = bindError is null
            ? $"created=1&bound={bindings.Count}"
            : $"created=1&bindError={Uri.EscapeDataString(Truncate(bindError, 300))}";
        NavigationManager.NavigateTo($"/deployment/instances/{id}/configure?{query}");
    }

    /// <summary>Keeps a failure message short enough to ride in the query string.</summary>
    private static string Truncate(string s, int n) => s.Length <= n ? s : s[..n] + "…";

    private void GoBack() => NavigationManager.NavigateTo("/deployment/topology");

    // CentralUI-024: delegates to the shared helper so the claim type stays
    // resolved through JwtTokenService rather than a duplicated magic string.
    private Task<string> GetCurrentUserAsync()
        => AuthStateProvider.RequireRoleAsync(ZB.MOM.WW.ScadaBridge.Security.Roles.Deployer);

    /// <summary>
    /// Opens the folder-tree template picker. A pick clears any dangling-id hint and
    /// re-runs the bindings preview; Cancel (or re-picking the same template) is a no-op.
    /// </summary>
    private async Task OpenTemplatePickerAsync()
    {
        if (_templates.Count == 0) return;
        var picked = await Dialog.ShowAsync<TemplatePickerDialog.TemplatePickResult>(
            "Choose template",
            ctx => @<TemplatePickerDialog Context="ctx" Folders="_folders" Templates="_templates"
                                          InitialTemplateId="@(_createTemplateId > 0 ? _createTemplateId : null)" />,
            size: "modal-lg");
        if (picked is null || picked.TemplateId == _createTemplateId) return;
        _createTemplateId = picked.TemplateId;
        _templateHint = null;
        await OnTemplateOrSiteChangedAsync();
    }
}