@page "/deployment/instances/{Id:int}/configure"
@using ScadaLink.Security
@using ScadaLink.Commons.Entities.Instances
@using ScadaLink.Commons.Entities.Sites
@using ScadaLink.Commons.Entities.Templates
@using ScadaLink.Commons.Interfaces.Repositories
@using ScadaLink.Commons.Types.Enums
@using ScadaLink.TemplateEngine.Services
@attribute [Authorize(Policy = AuthorizationPolicies.RequireDeployment)]
@inject ITemplateEngineRepository TemplateEngineRepository
@inject ISiteRepository SiteRepository
@inject InstanceService InstanceService
@inject AuthenticationStateProvider AuthStateProvider
@inject NavigationManager NavigationManager

<div class="container-fluid mt-3">
    <div class="d-flex align-items-center mb-3">
        <button class="btn btn-outline-secondary btn-sm me-3" @onclick="GoBack">&larr; Back to Instances</button>
        <h4 class="mb-0">Configure Instance</h4>
    </div>

    <ToastNotification @ref="_toast" />

    @if (_loading)
    {
        <LoadingSpinner IsLoading="true" />
    }
    else if (_errorMessage != null)
    {
        <div class="alert alert-danger">@_errorMessage</div>
    }
    else if (_instance != null)
    {
        @* Instance Identity *@
        <div class="card mb-3">
            <div class="card-body py-2">
                <div class="row">
                    <div class="col-md-4">
                        <small class="text-muted">Instance</small>
                        <div><strong>@_instance.UniqueName</strong></div>
                    </div>
                    <div class="col-md-2">
                        <small class="text-muted">Template</small>
                        <div>@_templateName</div>
                    </div>
                    <div class="col-md-2">
                        <small class="text-muted">Site</small>
                        <div>@_siteName</div>
                    </div>
                    <div class="col-md-2">
                        <small class="text-muted">Status</small>
                        <div><span class="badge @GetStateBadge(_instance.State)">@_instance.State</span></div>
                    </div>
                    <div class="col-md-2">
                        <small class="text-muted">Area</small>
                        <div>@(_instance.AreaId.HasValue ? _areaName : "—")</div>
                    </div>
                </div>
            </div>
        </div>

        @* Connection Bindings *@
        <div class="card mb-3">
            <div class="card-header py-2 d-flex justify-content-between align-items-center">
                <strong>Connection Bindings</strong>
                @if (_bindingDataSourceAttrs.Count > 0 && _siteConnections.Count > 0)
                {
                    <div class="d-flex align-items-center gap-1">
                        <select class="form-select form-select-sm" style="width: auto;" @bind="_bulkConnectionId">
                            <option value="0">Assign all to...</option>
                            @foreach (var c in _siteConnections)
                            {
                                <option value="@c.Id">@c.Name (@c.Protocol)</option>
                            }
                        </select>
                        <button class="btn btn-outline-primary btn-sm" @onclick="ApplyBulkBinding"
                                disabled="@(_bulkConnectionId == 0)">Apply</button>
                    </div>
                }
            </div>
            <div class="card-body p-0">
                @if (_bindingDataSourceAttrs.Count == 0)
                {
                    <p class="text-muted small p-3 mb-0">No data-sourced attributes in this template.</p>
                }
                else
                {
                    <table class="table table-sm table-bordered mb-0">
                        <thead class="table-light">
                            <tr>
                                <th>Attribute</th>
                                <th>Tag Path</th>
                                <th style="width: 280px;">Connection</th>
                            </tr>
                        </thead>
                        <tbody>
                            @foreach (var attr in _bindingDataSourceAttrs)
                            {
                                <tr>
                                    <td class="small">@attr.Name</td>
                                    <td class="small text-muted font-monospace">@attr.DataSourceReference</td>
                                    <td>
                                        <select class="form-select form-select-sm"
                                                value="@GetBindingConnectionId(attr.Name)"
                                                @onchange="(e) => OnBindingChanged(attr.Name, e)">
                                            <option value="0">— none —</option>
                                            @foreach (var c in _siteConnections)
                                            {
                                                <option value="@c.Id">@c.Name</option>
                                            }
                                        </select>
                                    </td>
                                </tr>
                            }
                        </tbody>
                    </table>
                    <div class="p-2">
                        <button class="btn btn-success btn-sm" @onclick="SaveBindings" disabled="@_saving">Save Bindings</button>
                    </div>
                }
            </div>
        </div>

        @* Attribute Overrides *@
        <div class="card mb-3">
            <div class="card-header py-2">
                <strong>Attribute Overrides</strong>
            </div>
            <div class="card-body p-0">
                @if (_overrideAttrs.Count == 0)
                {
                    <p class="text-muted small p-3 mb-0">No overridable (non-locked) attributes in this template.</p>
                }
                else
                {
                    <table class="table table-sm table-bordered mb-0">
                        <thead class="table-light">
                            <tr>
                                <th>Attribute</th>
                                <th>Type</th>
                                <th>Template Value</th>
                                <th style="width: 280px;">Override Value</th>
                            </tr>
                        </thead>
                        <tbody>
                            @foreach (var attr in _overrideAttrs)
                            {
                                <tr>
                                    <td class="small">@attr.Name</td>
                                    <td><span class="badge bg-light text-dark">@attr.DataType</span></td>
                                    <td class="small text-muted">@(attr.Value ?? "—")</td>
                                    <td>
                                        <input type="text" class="form-control form-control-sm"
                                               value="@GetOverrideValue(attr.Name)"
                                               @onchange="(e) => OnOverrideChanged(attr.Name, e)" />
                                    </td>
                                </tr>
                            }
                        </tbody>
                    </table>
                    <div class="p-2">
                        <button class="btn btn-success btn-sm" @onclick="SaveOverrides" disabled="@_saving">Save Overrides</button>
                    </div>
                }
            </div>
        </div>

        @* Area Assignment *@
        <div class="card mb-3">
            <div class="card-header py-2">
                <strong>Area Assignment</strong>
            </div>
            <div class="card-body py-2">
                <div class="d-flex align-items-center gap-2">
                    <select class="form-select form-select-sm" style="width: auto;" @bind="_reassignAreaId">
                        <option value="0">No area</option>
                        @foreach (var a in _siteAreas)
                        {
                            <option value="@a.Id">@a.Name</option>
                        }
                    </select>
                    <button class="btn btn-outline-primary btn-sm" @onclick="ReassignArea" disabled="@_saving">Set Area</button>
                </div>
            </div>
        </div>
    }
</div>

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

    private Instance? _instance;
    private string _templateName = "";
    private string _siteName = "";
    private string _areaName = "";
    private bool _loading = true;
    private bool _saving;
    private string? _errorMessage;
    private ToastNotification _toast = default!;

    // Bindings
    private List<TemplateAttribute> _bindingDataSourceAttrs = new();
    private List<DataConnection> _siteConnections = new();
    private Dictionary<string, int> _bindingSelections = new();
    private int _bulkConnectionId;

    // Overrides
    private List<TemplateAttribute> _overrideAttrs = new();
    private Dictionary<string, string?> _overrideValues = new();

    // Area
    private List<Area> _siteAreas = new();
    private int _reassignAreaId;

    protected override async Task OnInitializedAsync()
    {
        try
        {
            _instance = await TemplateEngineRepository.GetInstanceByIdAsync(Id);
            if (_instance == null)
            {
                _errorMessage = $"Instance #{Id} not found.";
                _loading = false;
                return;
            }

            // Identity
            var template = await TemplateEngineRepository.GetTemplateByIdAsync(_instance.TemplateId);
            _templateName = template?.Name ?? $"#{_instance.TemplateId}";

            var sites = await SiteRepository.GetAllSitesAsync();
            _siteName = sites.FirstOrDefault(s => s.Id == _instance.SiteId)?.Name ?? $"#{_instance.SiteId}";

            // Areas
            _siteAreas = (await TemplateEngineRepository.GetAreasBySiteIdAsync(_instance.SiteId)).ToList();
            _reassignAreaId = _instance.AreaId ?? 0;
            _areaName = _siteAreas.FirstOrDefault(a => a.Id == _reassignAreaId)?.Name ?? "";

            // Bindings
            var attrs = await TemplateEngineRepository.GetAttributesByTemplateIdAsync(_instance.TemplateId);
            _bindingDataSourceAttrs = attrs.Where(a => !string.IsNullOrEmpty(a.DataSourceReference)).ToList();
            _siteConnections = (await SiteRepository.GetDataConnectionsBySiteIdAsync(_instance.SiteId)).ToList();
            var existingBindings = await TemplateEngineRepository.GetBindingsByInstanceIdAsync(Id);
            foreach (var b in existingBindings)
                _bindingSelections[b.AttributeName] = b.DataConnectionId;

            // Overrides
            _overrideAttrs = attrs.Where(a => !a.IsLocked).ToList();
            var existingOverrides = await TemplateEngineRepository.GetOverridesByInstanceIdAsync(Id);
            foreach (var o in existingOverrides)
                _overrideValues[o.AttributeName] = o.OverrideValue;
        }
        catch (Exception ex)
        {
            _errorMessage = $"Failed to load instance: {ex.Message}";
        }
        _loading = false;
    }

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

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

    // ── Bindings ────────────────────────────────────────────

    private int GetBindingConnectionId(string attrName)
        => _bindingSelections.GetValueOrDefault(attrName, 0);

    private void OnBindingChanged(string attrName, ChangeEventArgs e)
    {
        var val = int.TryParse(e.Value?.ToString(), out var id) ? id : 0;
        if (val == 0) _bindingSelections.Remove(attrName);
        else _bindingSelections[attrName] = val;
    }

    private void ApplyBulkBinding()
    {
        if (_bulkConnectionId == 0) return;
        foreach (var attr in _bindingDataSourceAttrs)
            _bindingSelections[attr.Name] = _bulkConnectionId;
    }

    private async Task SaveBindings()
    {
        _saving = true;
        try
        {
            var bindings = _bindingSelections.Select(kv => (kv.Key, kv.Value)).ToList();
            var user = await GetCurrentUserAsync();
            var result = await InstanceService.SetConnectionBindingsAsync(Id, bindings, user);
            if (result.IsSuccess)
                _toast.ShowSuccess($"Saved {bindings.Count} connection binding(s).");
            else
                _toast.ShowError($"Save failed: {result.Error}");
        }
        catch (Exception ex)
        {
            _toast.ShowError($"Save failed: {ex.Message}");
        }
        _saving = false;
    }

    // ── Overrides ───────────────────────────────────────────

    private string? GetOverrideValue(string attrName)
        => _overrideValues.GetValueOrDefault(attrName);

    private void OnOverrideChanged(string attrName, ChangeEventArgs e)
    {
        var val = e.Value?.ToString();
        if (string.IsNullOrEmpty(val)) _overrideValues.Remove(attrName);
        else _overrideValues[attrName] = val;
    }

    private async Task SaveOverrides()
    {
        _saving = true;
        try
        {
            var user = await GetCurrentUserAsync();
            foreach (var (attrName, value) in _overrideValues)
                await InstanceService.SetAttributeOverrideAsync(Id, attrName, value, user);
            _toast.ShowSuccess($"Saved {_overrideValues.Count} override(s).");
        }
        catch (Exception ex)
        {
            _toast.ShowError($"Save overrides failed: {ex.Message}");
        }
        _saving = false;
    }

    // ── Area ────────────────────────────────────────────────

    private async Task ReassignArea()
    {
        _saving = true;
        try
        {
            var user = await GetCurrentUserAsync();
            var result = await InstanceService.AssignToAreaAsync(Id, _reassignAreaId == 0 ? null : _reassignAreaId, user);
            if (result.IsSuccess)
            {
                _areaName = _siteAreas.FirstOrDefault(a => a.Id == _reassignAreaId)?.Name ?? "";
                _toast.ShowSuccess("Area reassigned.");
            }
            else
                _toast.ShowError($"Reassign failed: {result.Error}");
        }
        catch (Exception ex)
        {
            _toast.ShowError($"Reassign failed: {ex.Message}");
        }
        _saving = false;
    }

    private static string GetStateBadge(InstanceState state) => state switch
    {
        InstanceState.Enabled => "bg-success",
        InstanceState.Disabled => "bg-secondary",
        InstanceState.NotDeployed => "bg-light text-dark",
        _ => "bg-secondary"
    };
}
