@using System.Numerics;
@inject IDbContextFactory<HBContext> dbFactory;
@implements IDialog

<Dialog Title="Edit permissions" @ref=dialog>
    @if(obj?.Acl is not null) {
        <table class="data-table">
            <tr>
                <th>Action</th>
                <th>Subject</th>
                <th>Permissions</th>
                <th></th>
            </tr>
            @foreach(var rule in obj.Acl.Rules.OrderByDescending(r => r.Action)) {
                <tr>
                    <td><div><AclActionSwitch InitialValue=@(rule.Action == AclRuleAction.Allow)/></div></td>
                    <td>@rule.Principal.ToString()</td>
                    <td>@GetActivePermissions(rule)</td>
                    <td>
                        <a title="Edit" href="javascript:;">&#x1F589</a>
                        <a title="Delete" href="javascript:;">&#x2716</a>
                    </td>
                </tr>
            }
        </table>
        <br/>
        <center><a href="javascript:;">Add new</a></center>
        <ButtonContainer>
            <button class="secondary" @onclick=Hide>Cancel</button>
            <button data-keyboard-shortcut="a" @onclick=Hide><u>A</u>pply</button>
        </ButtonContainer>
    } else {
        <center><i>This item does not have any permissions set!</i></center>
        <ButtonContainer>
            <button class="secondary" @onclick=Hide>Cancel</button>
        </ButtonContainer>
    }
</Dialog>

@code {
    public bool Visible {
        get => dialog.Visible;
        set {
            dialog.Visible = value;
            if(value)
                StateHasChanged();
        }
    }

    private HBObject? obj;

    private Dialog dialog;

    public void Show() => Visible = true;
    public void Hide() => Visible = false;

    public void Show(HBObject obj) {
        Object = obj;
        Show();
    }

    public HBObject? Object {
        get => obj;
        set {
            if(value is null) {
                obj = null;
                return;
            }

            using var db = dbFactory.CreateDbContext();

            obj = db.Objects
                .Include(o => o.Acl)
                .First(o => o.ObjectId == value.ObjectId);

            if(obj.Acl is not null)
                db.Entry(obj.Acl).Collection(a => a.Rules).Load();
        }
    }

    public string GetActivePermissions(AclRule rule) {
        var perms = Acl.GetPermissionDescriptions(obj!)
            .Where(kv => (rule.Permissions & kv.Value) == kv.Value)
            .ToList();

        // Filter the list of matching permissions to include the
        // most relevant encapsulation permissions only. E.g. if
        // 'Full access' includes 'Read' and 'Write', then only
        // show 'Full access'.
        List<int> toRemove = new();
        for(int i = 0; i < perms.Count(); i++)
            for(int j = 0; j < perms.Count(); j++)
                if(i != j)
                    if((perms[i].Value & perms[j].Value) == perms[i].Value)
                        toRemove.Add(i);
        for(int i = toRemove.Count() - 1; i >= 0; i--)
            perms.RemoveAt(toRemove[i]);

        return string.Join(", ", perms
            .OrderByDescending(kv => BitOperations.PopCount(kv.Value))
            .ThenByDescending(kv => kv.Value)
            .Select(kv => kv.Key));
    }
}