@page "/clusters/{ClusterId}/acls/new"
@page "/clusters/{ClusterId}/acls/{NodeAclId}"
@attribute [Authorize(Policy = AdminUiPolicies.ConfigEditor)]
@rendermode RenderMode.InteractiveServer
@using Microsoft.AspNetCore.Components.Forms
@using Microsoft.EntityFrameworkCore
@using System.ComponentModel.DataAnnotations
@using ZB.MOM.WW.OtOpcUa.AdminUI.Acls
@using ZB.MOM.WW.OtOpcUa.Configuration
@using ZB.MOM.WW.OtOpcUa.Configuration.Entities
@using ZB.MOM.WW.OtOpcUa.Configuration.Enums
@using ZB.MOM.WW.OtOpcUa.Core.Authorization
@inject IDbContextFactory<OtOpcUaConfigDbContext> DbFactory
@inject IAclScopeService Scopes
@inject NavigationManager Nav

<div class="d-flex justify-content-between align-items-center mb-3">
    <h4 class="mb-0">@(IsNew ? "New ACL grant" : "Edit ACL grant") &middot; <span class="mono">@ClusterId</span></h4>
    <a href="/clusters/@ClusterId/acls" class="btn btn-outline-secondary btn-sm">Cancel</a>
</div>

<ClusterNav ClusterId="@ClusterId" ActiveTab="acls" />

@if (!_loaded)
{
    <p>Loading…</p>
}
else if (!IsNew && _existing is null)
{
    <section class="panel notice rise" style="animation-delay:.02s">ACL <span class="mono">@NodeAclId</span> not found.</section>
}
else
{
    <EditForm Model="_form" OnValidSubmit="SubmitAsync" FormName="aclEdit">
        <DataAnnotationsValidator />
        <ValidationSummary class="alert alert-danger" />
        <section class="panel rise" style="animation-delay:.02s">
            <div class="panel-head">Grant</div>
            <div style="padding:1rem">
                <div class="row">
                    <div class="col-md-6 mb-3">
                        <label class="form-label" for="aid">NodeAclId</label>
                        <InputText id="aid" @bind-Value="_form.NodeAclId" disabled="@(!IsNew)" class="form-control form-control-sm mono" />
                    </div>
                    <div class="col-md-6 mb-3">
                        <label class="form-label" for="grp">Principal</label>
                        <input id="grp" class="form-control form-control-sm mono" list="acl-principals"
                               placeholder="scadabridge-dcl"
                               @bind="_form.Principal" @bind:after="RefreshPrincipalAsync" />
                        <datalist id="acl-principals">
                            @foreach (var p in _knownPrincipals)
                            {
                                <option value="@p"></option>
                            }
                        </datalist>
                        <div class="form-text">
                            @if (string.IsNullOrWhiteSpace(_form.Principal))
                            {
                                <span>
                                    An API key's principal, or the reserved
                                    <span class="mono">@OpcUaPrincipals.Anonymous</span> principal that an
                                    anonymous session authenticates as. Mint keys on
                                    <a href="/apikeys">/apikeys</a>.
                                </span>
                            }
                            else if (_principal.IsAnonymous)
                            {
                                <span class="text-success">
                                    ✓ The reserved anonymous principal — every session admitted without a
                                    key authenticates as this.
                                </span>
                            }
                            else if (_principal.EnabledKeys > 0)
                            {
                                <span class="text-success">
                                    ✓ @_principal.EnabledKeys active API key@(_principal.EnabledKeys == 1 ? "" : "s")
                                    @(_principal.DisabledKeys > 0 ? $" (+{_principal.DisabledKeys} revoked or expired)" : "")
                                    authenticate@(_principal.EnabledKeys == 1 ? "s" : "") as this principal.
                                </span>
                            }
                            else
                            {
                                <span class="text-warning">
                                    ⚠ No active API key uses this principal@(_principal.DisabledKeys > 0 ? " (only revoked or expired ones)" : "") —
                                    the grant is valid but currently authorizes nobody. That is fine if the
                                    key is still to be minted; otherwise check the spelling.
                                </span>
                            }
                        </div>
                    </div>
                </div>

                <div class="mb-3">
                    <label class="form-label">Scope</label>
                    <div class="d-flex align-items-center gap-2 flex-wrap">
                        <span class="chip chip-idle">@_form.ScopeKind</span>
                        <span class="mono small">@(string.IsNullOrEmpty(_form.ScopeId) ? "(whole cluster)" : _form.ScopeId)</span>
                        <button type="button" class="btn btn-sm btn-outline-primary" @onclick="OpenPicker">
                            Choose scope…
                        </button>
                    </div>
                    <div class="form-text @(_scope.Ok ? "text-success" : "text-danger")">
                        @(_scope.Ok ? "✓ " : "✗ ")@_scope.Message
                    </div>
                    <div class="form-text">
                        Permissions inherit downward: a grant on a device covers every tag beneath it.
                        Picking the scope from the tree is what keeps the kind and the target in step —
                        a kind that disagrees with its target resolves to nothing and authorizes nobody.
                    </div>
                </div>

                <div class="mb-3">
                    <label class="form-label">Permissions</label>
                    <div>
                        @foreach (var bit in PermissionBits)
                        {
                            <div class="form-check form-check-inline">
                                <input type="checkbox" class="form-check-input"
                                       id="perm-@bit"
                                       checked="@_form.HasPerm(bit)"
                                       @onchange="e => _form.SetPerm(bit, (bool)e.Value!)" />
                                <label class="form-check-label" for="perm-@bit">@bit</label>
                            </div>
                        }
                    </div>
                    <div class="form-text mt-2">
                        Bundles:
                        <div class="btn-group btn-group-sm ms-1" role="group">
                            <button type="button" class="btn btn-sm btn-outline-secondary" @onclick="() => _form.PermissionFlags = NodePermissions.ReadOnly">ReadOnly</button>
                            <button type="button" class="btn btn-sm btn-outline-secondary" @onclick="() => _form.PermissionFlags = NodePermissions.Operator">Operator</button>
                            <button type="button" class="btn btn-sm btn-outline-secondary" @onclick="() => _form.PermissionFlags = NodePermissions.Engineer">Engineer</button>
                            <button type="button" class="btn btn-sm btn-outline-secondary" @onclick="() => _form.PermissionFlags = NodePermissions.Admin">Admin</button>
                        </div>
                    </div>
                </div>
                <div class="mb-3">
                    <label class="form-label">Notes</label>
                    <InputTextArea @bind-Value="_form.Notes" class="form-control form-control-sm" rows="3" />
                </div>
            </div>
        </section>

        @if (!string.IsNullOrWhiteSpace(_error)) { <div class="panel notice notice-alert mt-3">@_error</div> }

        <div class="mt-3 d-flex gap-2">
            <div class="btn-group" role="group">
                <button type="submit" class="btn btn-primary" disabled="@_busy">@(IsNew ? "Create" : "Save changes")</button>
                <a href="/clusters/@ClusterId/acls" class="btn btn-outline-secondary">Cancel</a>
            </div>
            @if (!IsNew) { <button type="button" class="btn btn-outline-danger ms-auto" @onclick="DeleteAsync" disabled="@_busy">Delete</button> }
        </div>
    </EditForm>

    <AclScopePickerModal Visible="_pickerVisible" ClusterId="@ClusterId"
                         OnPicked="ScopePicked" OnCancel="() => _pickerVisible = false" />
}

@code {
    private static readonly NodePermissions[] PermissionBits =
    [
        NodePermissions.Browse, NodePermissions.Read, NodePermissions.Subscribe, NodePermissions.HistoryRead,
        NodePermissions.WriteOperate, NodePermissions.WriteTune, NodePermissions.WriteConfigure,
        NodePermissions.AlarmRead, NodePermissions.AlarmAcknowledge, NodePermissions.AlarmConfirm, NodePermissions.AlarmShelve,
        NodePermissions.MethodCall,
    ];

    [Parameter] public string ClusterId { get; set; } = "";
    [Parameter] public string? NodeAclId { get; set; }

    private bool IsNew => string.IsNullOrEmpty(NodeAclId);

    private FormModel _form = new();
    private NodeAcl? _existing;
    private bool _loaded;
    private bool _busy;
    private string? _error;
    private bool _pickerVisible;

    private IReadOnlyList<string> _knownPrincipals = Array.Empty<string>();
    private PrincipalUsage _principal;
    private AclScopeCheck _scope;

    protected override async Task OnInitializedAsync()
    {
        if (!IsNew)
        {
            await using var db = await DbFactory.CreateDbContextAsync();
            _existing = await db.NodeAcls.AsNoTracking().FirstOrDefaultAsync(
                a => a.ClusterId == ClusterId && a.NodeAclId == NodeAclId);
            if (_existing is not null)
            {
                _form = new FormModel
                {
                    NodeAclId = _existing.NodeAclId,
                    Principal = _existing.Principal,
                    ScopeKind = _existing.ScopeKind,
                    ScopeId = _existing.ScopeId,
                    PermissionFlags = _existing.PermissionFlags,
                    Notes = _existing.Notes,
                    RowVersion = _existing.RowVersion,
                };
            }
        }

        _knownPrincipals = await Scopes.LoadKnownPrincipalsAsync();
        await RefreshPrincipalAsync();
        await RefreshScopeAsync();
        _loaded = true;
    }

    private void OpenPicker()
    {
        _pickerVisible = true;
        StateHasChanged();
    }

    private async Task ScopePicked(AclScopeNode node)
    {
        // The picker supplies both halves at once — the pairing is what stops a kind naming one entity
        // type while its id names another.
        _form.ScopeKind = node.ScopeKind!.Value;
        _form.ScopeId = node.ScopeId;
        _pickerVisible = false;
        await RefreshScopeAsync();
    }

    private async Task RefreshPrincipalAsync() =>
        _principal = await Scopes.CheckPrincipalAsync(_form.Principal ?? "");

    private async Task RefreshScopeAsync() =>
        _scope = await Scopes.CheckScopeAsync(ClusterId, _form.ScopeKind, _form.ScopeId);

    private async Task SubmitAsync()
    {
        _busy = true; _error = null;
        try
        {
            // Re-check rather than trust the cached verdict: an existing row may have been loaded with a
            // scope whose entity has since been deleted, and the operator may never have touched the
            // picker. Blocking here is what stops the page saving a grant the deployment would reject.
            await RefreshScopeAsync();
            if (!_scope.Ok) { _error = $"Scope: {_scope.Message}"; return; }

            await using var db = await DbFactory.CreateDbContextAsync();
            if (IsNew)
            {
                if (await db.NodeAcls.AnyAsync(a => a.NodeAclId == _form.NodeAclId))
                { _error = $"ACL '{_form.NodeAclId}' already exists."; return; }
                db.NodeAcls.Add(new NodeAcl
                {
                    NodeAclId = _form.NodeAclId,
                    ClusterId = ClusterId,
                    Principal = _form.Principal,
                    ScopeKind = _form.ScopeKind,
                    ScopeId = string.IsNullOrWhiteSpace(_form.ScopeId) ? null : _form.ScopeId,
                    PermissionFlags = _form.PermissionFlags,
                    Notes = string.IsNullOrWhiteSpace(_form.Notes) ? null : _form.Notes,
                });
            }
            else
            {
                var entity = await db.NodeAcls.FirstOrDefaultAsync(a => a.ClusterId == ClusterId && a.NodeAclId == NodeAclId);
                if (entity is null) { _error = "Row no longer exists."; return; }
                db.Entry(entity).Property(e => e.RowVersion).OriginalValue = _form.RowVersion;
                entity.Principal = _form.Principal;
                entity.ScopeKind = _form.ScopeKind;
                entity.ScopeId = string.IsNullOrWhiteSpace(_form.ScopeId) ? null : _form.ScopeId;
                entity.PermissionFlags = _form.PermissionFlags;
                entity.Notes = string.IsNullOrWhiteSpace(_form.Notes) ? null : _form.Notes;
            }
            await db.SaveChangesAsync();
            Nav.NavigateTo($"/clusters/{ClusterId}/acls");
        }
        catch (DbUpdateConcurrencyException) { _error = "Another user changed this ACL while you were editing."; }
        catch (Exception ex) { _error = ex.Message; }
        finally { _busy = false; }
    }

    private async Task DeleteAsync()
    {
        if (IsNew) return;
        _busy = true; _error = null;
        try
        {
            await using var db = await DbFactory.CreateDbContextAsync();
            var entity = await db.NodeAcls.FirstOrDefaultAsync(a => a.ClusterId == ClusterId && a.NodeAclId == NodeAclId);
            if (entity is null) { Nav.NavigateTo($"/clusters/{ClusterId}/acls"); return; }
            db.Entry(entity).Property(e => e.RowVersion).OriginalValue = _form.RowVersion;
            db.NodeAcls.Remove(entity);
            await db.SaveChangesAsync();
            Nav.NavigateTo($"/clusters/{ClusterId}/acls");
        }
        catch (DbUpdateConcurrencyException) { _error = "Another user changed this ACL while you were viewing it."; }
        catch (Exception ex) { _error = ex.Message; }
        finally { _busy = false; }
    }

    private sealed class FormModel
    {
        [Required, RegularExpression("^[A-Za-z0-9_-]+$")] public string NodeAclId { get; set; } = "";
        [Required] public string Principal { get; set; } = "";
        public NodeAclScopeKind ScopeKind { get; set; } = NodeAclScopeKind.Cluster;
        public string? ScopeId { get; set; }
        public NodePermissions PermissionFlags { get; set; } = NodePermissions.None;
        public string? Notes { get; set; }
        public byte[] RowVersion { get; set; } = [];

        public bool HasPerm(NodePermissions bit) => PermissionFlags.HasFlag(bit);
        public void SetPerm(NodePermissions bit, bool on)
        {
            if (on) PermissionFlags |= bit;
            else PermissionFlags &= ~bit;
        }
    }
}