@page "/"
@inject IJSRuntime JS
@inject PreciseLocationService LocationService
@inject CadastralCatalogService CatalogService
@inject OfficialCadastreService OfficialCadastreService
@inject LocationSearchService LocationSearchService
@inject AzureMapsService AzureMapsService
@inject ProjectStorageService ProjectStorageService
@implements IAsyncDisposable

<PageTitle>LME Mappe Catastali</PageTitle>

<div class="map-app">
    <section class="map-stage">
        <div id="map"></div>

        <header class="map-toolbar">
            <div class="app-identity">
                <strong>LME Catasto</strong>
                <span>@Status</span>
            </div>
            <div class="toolbar-actions">
                <button class="toolbar-button layer-button @(LayerPanelOpen ? "is-active" : null)"
                        title="Layer catastali"
                        aria-expanded="@LayerPanelOpen"
                        @onclick="ToggleLayerPanel">
                    <span class="layer-symbol" aria-hidden="true"></span>
                    <span>Layer</span>
                </button>
                <button class="toolbar-button" @onclick='() => SelectTab(ActiveTab == "search" ? "map" : "search")'>Cerca</button>
            </div>
        </header>

        <div class="map-search @(ActiveTab == "search" ? "is-open" : null)">
            <input @bind="SearchText" @bind:event="oninput" placeholder="Localita, indirizzo o coordinate" />
            <button @onclick="SearchLocation">Vai</button>
        </div>

        @if (LayerPanelOpen)
        {
            <section class="map-layer-panel" aria-label="Layer catastali">
                <header>
                    <strong>Layer catastali</strong>
                    <button class="layer-panel-close" aria-label="Chiudi layer" @onclick="ToggleLayerPanel">×</button>
                </header>
                @foreach (var layer in CadastralLayers)
                {
                    <label class="map-layer-option">
                        <input type="checkbox" checked="@layer.Enabled" @onchange="(args) => ToggleCadastreLayer(layer, args)" />
                        <span>
                            <strong>@layer.Name</strong>
                            @if (!string.IsNullOrWhiteSpace(layer.Detail))
                            {
                                <small>@layer.Detail</small>
                            }
                        </span>
                    </label>
                }
                <div class="layer-panel-actions">
                    <button class="secondary-command" @onclick="ClearSelectedParcels">Rimuovi particelle selezionate</button>
                    <button class="danger-command" @onclick="ClearMapElements">Pulisci elementi mappa</button>
                </div>
            </section>
        }

        <div class="gps-overlay @(ActiveTab == "search" ? "search-open" : null)">
            <div class="gps-state">
                <span id="gpsState">GPS non attivo</span>
                <strong id="parcelState">Nessuna particella selezionata</strong>
            </div>
            <button class="gps-main" @onclick="ToggleGps">@(GpsActive ? "Ferma GPS" : "Avvia GPS")</button>
            <button class="gps-center" @onclick="CenterOnGps" aria-label="Centra posizione">Centra</button>
        </div>

        @if (ActiveTab is not "map" and not "search")
        {
            <aside class="tool-sheet">
                <div class="sheet-header">
                    <div>
                        <p class="eyebrow">@PanelEyebrow</p>
                        <h1>@PanelTitle</h1>
                    </div>
                    <button class="close-button" @onclick='() => SelectTab("map")' aria-label="Chiudi pannello">×</button>
                </div>

                @if (ActiveTab == "cadastre")
                {
                    <section class="panel-content">
                        <label>
                            Regione
                            <select value="@SelectedRegionFile" @onchange="OnRegionChanged">
                                <option value="">Seleziona regione</option>
                                @foreach (var region in Regions)
                                {
                                    <option value="@region.DataFile">@region.Name</option>
                                }
                            </select>
                        </label>

                        <label>
                            Comune
                            <select value="@SelectedMunicipalityCode" @onchange="OnMunicipalityChanged" disabled="@(Municipalities.Count == 0)">
                                <option value="">Seleziona comune</option>
                                @foreach (var municipality in Municipalities)
                                {
                                    <option value="@municipality.Code">@municipality.Name (@municipality.Code)</option>
                                }
                            </select>
                        </label>

                        <label>
                            Foglio
                            <select value="@SelectedSheet" @onchange="OnSheetChanged" disabled="@(Sheets.Count == 0 || CatalogBusy)">
                                <option value="">Seleziona foglio</option>
                                @foreach (var sheet in Sheets)
                                {
                                    <option value="@sheet">@DisplaySheet(sheet)</option>
                                }
                            </select>
                        </label>

                        <label>
                            Particella
                            <select value="@SelectedParcelNumber" @onchange="OnParcelChanged" disabled="@(Parcels.Count == 0 || CatalogBusy)">
                                <option value="">Seleziona particella</option>
                                @foreach (var parcel in Parcels)
                                {
                                    <option value="@parcel.Number">@parcel.Number</option>
                                }
                            </select>
                        </label>

                        @if (!string.IsNullOrWhiteSpace(CatalogMessage))
                        {
                            <div class="catalog-progress">
                                <span>@CatalogMessage</span>
                                @if (CatalogFraction.HasValue)
                                {
                                    <progress value="@CatalogFraction.Value" max="1"></progress>
                                }
                            </div>
                        }

                        <button class="primary-command" @onclick="LocateParcel" disabled="@(SelectedParcel is null || CatalogBusy)">Mostra particella sulla mappa</button>

                        <div class="service-note">
                            <strong>Mappa pubblica ufficiale</strong>
                            <p>I confini visualizzati arrivano dai servizi WMS/WFS open data dell'Agenzia delle Entrate e non richiedono CAPTCHA.</p>
                        </div>
                    </section>
                }
                else if (ActiveTab == "projects")
                {
                    <section class="panel-content">
                        <h2>File GIS</h2>
                        <label class="file-picker">
                            <span>Carica KML, KMZ o GeoJSON</span>
                            <input id="gisFileInput" type="file" accept=".kml,.kmz,.geojson,.json,application/vnd.google-earth.kml+xml,application/vnd.google-earth.kmz,application/geo+json" />
                        </label>
                        <label class="toggle-line project-save-option">
                            <input type="checkbox" checked="@ImportParcelsOnly" @onchange="ToggleImportParcelsOnly" />
                            <span>KML/KMZ: importa solo le particelle</span>
                        </label>
                        <label class="toggle-line project-save-option">
                            <input type="checkbox" checked="@ShowImportedMeasurements" @onchange="ToggleImportedMeasurements" />
                            <span>Mostra misure dei file caricati</span>
                        </label>
                        <div class="button-row">
                            <button @onclick="FitImportedLayers">Inquadra</button>
                            <button class="secondary-command" @onclick="ClearImportedLayers">Pulisci</button>
                        </div>

                        <h2>Archivio progetti</h2>
                        <label>
                            Nome progetto
                            <input @bind="NewProjectName" @bind:event="oninput" placeholder="Es. Rilievo San Nicola" maxlength="80" />
                        </label>
                        <label class="toggle-line project-save-option">
                            <input type="checkbox" @bind="IncludeCadastralParcels" />
                            <span>Includi le particelle catastali rosse</span>
                        </label>
                        <button class="primary-command" @onclick="SaveProject" disabled="@(ProjectBusy || string.IsNullOrWhiteSpace(NewProjectName))">Salva progetto</button>

                        <label>
                            Progetto salvato
                            <select value="@SelectedProjectId" @onchange="SelectProject" disabled="@(Projects.Count == 0 || ProjectBusy)">
                                <option value="">Seleziona un progetto</option>
                                @foreach (var project in Projects)
                                {
                                    <option value="@project.Id">@project.Name - @project.UpdatedAt.ToLocalTime().ToString("dd/MM/yyyy HH:mm")</option>
                                }
                            </select>
                        </label>
                        <div class="button-row">
                            <button @onclick="LoadProject" disabled="@(ProjectBusy || string.IsNullOrWhiteSpace(SelectedProjectId))">Carica</button>
                            <button class="danger-command" @onclick="DeleteProject" disabled="@(ProjectBusy || string.IsNullOrWhiteSpace(SelectedProjectId))">Elimina</button>
                        </div>
                        <div class="project-archive-state">@ProjectArchiveMessage</div>

                        <h2>Misura e disegna</h2>
                        <div class="measurement-mode-grid" aria-label="Strumenti di misura">
                            <button @onclick='() => StartMeasurementDrawing("area")'>Area</button>
                            <button @onclick='() => StartMeasurementDrawing("distance")'>Distanza</button>
                            <button @onclick='() => StartMeasurementDrawing("circle")'>Cerchio</button>
                        </div>
                        <label class="toggle-line project-save-option">
                            <input type="checkbox" checked="@ShowDrawingMeasurements" @onchange="ToggleDrawingMeasurements" />
                            <span>Mostra superficie, perimetro e lati</span>
                        </label>
                        <button class="secondary-command" aria-pressed="@DrawToolsVisible" @onclick="ToggleDrawTools">
                            @(DrawToolsVisible ? "Nascondi strumenti completi" : "Mostra strumenti completi")
                        </button>

                        <h2>POI</h2>
                        <label>
                            Nome POI
                            <input @bind="PoiName" @bind:event="oninput" placeholder="Nome del punto" />
                        </label>
                        <button class="primary-command" @onclick="AddProjectMarker">Aggiungi POI al centro mappa</button>
                        <button class="danger-command" @onclick="ClearDrawings">Elimina disegni e POI</button>
                    </section>
                }
                else if (ActiveTab == "settings")
                {
                    <section class="panel-content">
                        <h2>Visualizzazione</h2>
                        <label>
                            Sfondo
                            <select value="@SelectedBaseLayer" @onchange="ChangeBaseLayer">
                                <option value="satellite">Satellite - Esri World Imagery</option>
                                <option value="osm">Strade - OpenStreetMap</option>
                                <option value="streets-esri">Strade dettagliate - Esri World Street Map</option>
                                <option value="topographic">Topografica - Esri World Topographic</option>
                                <option value="terrain">Terreno - OpenTopoMap</option>
                                <option value="carto">Strade chiare - CARTO Voyager</option>
                                <option value="azure-road">Strade - Azure Maps</option>
                                <option value="azure-satellite">Satellite - Azure Maps</option>
                                <option value="google-satellite">Satellite - Google Maps</option>
                                <option value="google-roadmap">Strade - Google Maps</option>
                            </select>
                        </label>
                        <label>
                            Chiave Google Maps Platform
                            <input type="password" @bind="GoogleMapsApiKey" placeholder="API key" autocomplete="off" />
                        </label>
                        <button class="secondary-command" @onclick="SaveGoogleMapsApiKey">Salva chiave Google</button>
                        <label>
                            Chiave sottoscrizione Azure Maps Gen2
                            <input type="password" @bind="AzureMapsSubscriptionKey" placeholder="Subscription key" autocomplete="off" />
                        </label>
                        <button class="secondary-command" @onclick="SaveAzureMapsKey">Salva chiave Azure Maps</button>
                        <div class="service-note">
                            <strong>Quota gratuita Azure Maps Gen2</strong>
                            <p>Include ogni mese 5.000 transazioni per le mappe stradali e 1.000 per le immagini satellitari. Ogni transazione comprende fino a 15 tessere.</p>
                        </div>
                        <label>
                            Trasparenza catasto
                            <input type="range" min="0" max="1" step="0.05" value="0.75" @onchange="ChangeCadastreOpacity" />
                        </label>
                        <h2>GPS e percorso</h2>
                        <label class="toggle-line">
                            <input type="checkbox" checked="@TrailEnabled" @onchange="ToggleTrail" />
                            Registra la traccia mentre cammini
                        </label>

                        <h2>Servizi Agenzia delle Entrate</h2>
                        <div class="service-note protected-service">
                            <strong>Download documenti e fogli ufficiali</strong>
                            <p>Il CAPTCHA o l'accesso SPID/CIE vengono gestiti direttamente dal sito dell'Agenzia. Per sicurezza l'app non tenta di aggirarli.</p>
                            <button class="primary-command" @onclick="OpenOfficialGeoportal">Apri Geoportale catastale</button>
                            <button class="secondary-command" @onclick="OpenOfficialReservedArea">Apri Area riservata per download</button>
                        </div>

                        <button class="secondary-command" @onclick="ExportCadastralImage">Mostra vista WMS corrente</button>
                        <footer>Dati catastali: Agenzia delle Entrate, licenza CC BY 4.0. App indipendente.</footer>
                    </section>
                }
            </aside>
        }

        <div id="mapInfo" class="map-info">Pronto</div>

        <div id="wmsPreview" class="wms-preview" hidden>
            <section class="wms-preview-dialog" role="dialog" aria-modal="true" aria-labelledby="wmsPreviewTitle">
                <header>
                    <div>
                        <strong id="wmsPreviewTitle">Vista WMS catastale</strong>
                        <small>Immagine ufficiale AdE con le particelle evidenziate dall'app</small>
                    </div>
                    <button id="closeWmsPreview" class="close-button" aria-label="Chiudi vista WMS">×</button>
                </header>
                <div class="wms-preview-body">
                    <span id="wmsPreviewLoading">Caricamento...</span>
                    <div id="wmsPreviewMap" class="wms-preview-map" hidden>
                        <img id="wmsPreviewImage" alt="Vista WMS catastale dell'area corrente" />
                        <svg id="wmsPreviewOverlay" aria-hidden="true" preserveAspectRatio="none"></svg>
                    </div>
                </div>
            </section>
        </div>

        <nav class="bottom-tabs" aria-label="Sezioni principali">
            <button class="@(ActiveTab == "map" || ActiveTab == "search" ? "active" : null)" @onclick='() => SelectTab("map")'>Mappa</button>
            <button class="@(ActiveTab == "cadastre" ? "active" : null)" @onclick='() => SelectTab("cadastre")'>Catasto</button>
            <button class="@(ActiveTab == "projects" ? "active" : null)" @onclick='() => SelectTab("projects")'>Progetti</button>
            <button class="@(ActiveTab == "settings" ? "active" : null)" @onclick='() => SelectTab("settings")'>Impostazioni</button>
        </nav>
    </section>
</div>

@code {
    private string ActiveTab { get; set; } = "map";
    private string SearchText { get; set; } = string.Empty;
    private string NewProjectName { get; set; } = string.Empty;
    private string PoiName { get; set; } = string.Empty;
    private string SelectedProjectId { get; set; } = string.Empty;
    private string ProjectArchiveMessage { get; set; } = "Nessun progetto salvato.";
    private string Status { get; set; } = "online";
    private string SelectedBaseLayer { get; set; } = "satellite";
    private string GoogleMapsApiKey { get; set; } = string.Empty;
    private string AzureMapsSubscriptionKey { get; set; } = string.Empty;
    private string SelectedRegionFile { get; set; } = string.Empty;
    private string SelectedMunicipalityCode { get; set; } = string.Empty;
    private string SelectedSheet { get; set; } = string.Empty;
    private string SelectedParcelNumber { get; set; } = string.Empty;
    private string CatalogMessage { get; set; } = string.Empty;
    private double? CatalogFraction { get; set; }
    private bool CatalogBusy { get; set; }
    private bool GpsActive { get; set; }
    private bool DrawToolsVisible { get; set; }
    private bool TrailEnabled { get; set; }
    private bool LayerPanelOpen { get; set; }
    private bool IncludeCadastralParcels { get; set; } = true;
    private bool ImportParcelsOnly { get; set; } = true;
    private bool ShowImportedMeasurements { get; set; }
    private bool ShowDrawingMeasurements { get; set; } = true;
    private bool ProjectBusy { get; set; }
    private CancellationTokenSource? CatalogCancellation { get; set; }
    private CancellationTokenSource? GpsLookupCancellation { get; set; }
    private long LastGpsLookupAt;
    private int GpsLookupInProgress;

    private IReadOnlyList<RegionOption> Regions { get; set; } = [];
    private IReadOnlyList<MunicipalityOption> Municipalities { get; set; } = [];
    private IReadOnlyList<string> Sheets { get; set; } = [];
    private IReadOnlyList<ParcelOption> Parcels { get; set; } = [];
    private IReadOnlyList<MapProjectSummary> Projects { get; set; } = [];

    private MunicipalityOption? SelectedMunicipality =>
        Municipalities.FirstOrDefault(item => item.Code == SelectedMunicipalityCode);

    private ParcelOption? SelectedParcel =>
        Parcels.FirstOrDefault(item => item.Number == SelectedParcelNumber);

    private string PanelTitle => ActiveTab switch
    {
        "cadastre" => "Ricerca catastale",
        "projects" => "Progetti e dati",
        "settings" => "Impostazioni",
        _ => string.Empty
    };

    private string PanelEyebrow => ActiveTab switch
    {
        "cadastre" => "Regione, Comune, Foglio, Particella",
        "projects" => "KML, KMZ, GeoJSON e POI",
        "settings" => "Mappa, GPS e servizi ufficiali",
        _ => string.Empty
    };

    private readonly List<CadastralLayer> CadastralLayers =
    [
        new("CP.CadastralParcel", "Confini particelle", true),
        new("codice_plla", "Numeri particelle", true, "Visibili circa da zoom 17"),
        new("CP.CadastralZoning", "Fogli catastali", true),
        new("fabbricati", "Fabbricati", true),
        new("strade", "Strade catastali", false),
        new("acque", "Acque", false)
    ];

    protected override async Task OnInitializedAsync()
    {
        try
        {
            GoogleMapsApiKey = await SecureStorage.Default.GetAsync("google_maps_api_key") ?? string.Empty;
        }
        catch
        {
            GoogleMapsApiKey = string.Empty;
        }

        try
        {
            AzureMapsSubscriptionKey = await SecureStorage.Default.GetAsync("azure_maps_subscription_key") ?? string.Empty;
        }
        catch
        {
            AzureMapsSubscriptionKey = string.Empty;
        }

        try
        {
            Regions = await CatalogService.GetRegionsAsync();
        }
        catch (Exception error)
        {
            CatalogMessage = $"Catalogo Comuni non disponibile: {error.Message}";
        }

        await RefreshProjectsAsync();
    }

    protected override async Task OnAfterRenderAsync(bool firstRender)
    {
        if (firstRender)
        {
            await JS.InvokeVoidAsync("lmeMap.init");
            await MigrateLegacyProjectAsync();
        }
    }

    private async Task MigrateLegacyProjectAsync()
    {
        try
        {
            var legacySnapshot = await JS.InvokeAsync<string?>("lmeMap.getLegacyProjectSnapshot");
            if (string.IsNullOrWhiteSpace(legacySnapshot))
            {
                return;
            }

            var migrated = await ProjectStorageService.SaveAsync(
                "Progetto precedente",
                legacySnapshot,
                false);
            await JS.InvokeVoidAsync("lmeMap.clearLegacyProjectSnapshot");
            await RefreshProjectsAsync();
            SelectedProjectId = migrated.Id;
            await InvokeAsync(StateHasChanged);
        }
        catch
        {
            // The legacy value remains available and migration can be retried at the next start.
        }
    }

    private async Task SelectTab(string tab)
    {
        ActiveTab = tab;
        if (tab != "map")
        {
            LayerPanelOpen = false;
        }
        if (tab == "projects")
        {
            await RefreshProjectsAsync();
        }
        await Task.Delay(30);
        await JS.InvokeVoidAsync("lmeMap.resize");
    }

    private async Task ToggleLayerPanel()
    {
        LayerPanelOpen = !LayerPanelOpen;
        if (LayerPanelOpen)
        {
            ActiveTab = "map";
        }

        await Task.Delay(30);
        await JS.InvokeVoidAsync("lmeMap.resize");
    }

    private async Task SearchLocation()
    {
        if (string.IsNullOrWhiteSpace(SearchText))
        {
            await JS.InvokeVoidAsync("lmeMap.showInfo", "Inserisci una localita, un indirizzo o due coordinate.");
            return;
        }

        try
        {
            Status = "ricerca...";
            var result = await LocationSearchService.SearchAsync(SearchText);
            if (result is null)
            {
                Status = "online";
                await JS.InvokeVoidAsync("lmeMap.showInfo", "Localita non trovata. Prova ad aggiungere Comune e Provincia.");
                return;
            }

            await JS.InvokeVoidAsync("lmeMap.showSearchResult", result.Latitude, result.Longitude, result.Label);
            ActiveTab = "map";
            Status = "online";
        }
        catch (Exception error)
        {
            Status = "errore ricerca";
            await JS.InvokeVoidAsync("lmeMap.showInfo", $"Ricerca non riuscita: {error.Message}");
        }
    }

    private async Task OnRegionChanged(ChangeEventArgs args)
    {
        CancelCatalogWork();
        SelectedRegionFile = args.Value?.ToString() ?? string.Empty;
        SelectedMunicipalityCode = string.Empty;
        SelectedSheet = string.Empty;
        SelectedParcelNumber = string.Empty;
        Sheets = [];
        Parcels = [];
        CatalogMessage = string.Empty;
        Municipalities = string.IsNullOrWhiteSpace(SelectedRegionFile)
            ? []
            : await CatalogService.GetMunicipalitiesAsync(SelectedRegionFile);
    }

    private async Task OnMunicipalityChanged(ChangeEventArgs args)
    {
        SelectedMunicipalityCode = args.Value?.ToString() ?? string.Empty;
        SelectedSheet = string.Empty;
        SelectedParcelNumber = string.Empty;
        Sheets = [];
        Parcels = [];
        var municipality = SelectedMunicipality;
        if (municipality is null)
        {
            return;
        }

        var token = BeginCatalogWork();
        CatalogBusy = true;
        CatalogMessage = "Preparo il catalogo regionale...";
        CatalogFraction = null;
        try
        {
            Sheets = await CatalogService.GetSheetsAsync(municipality, CreateProgress(), token);
            CatalogMessage = $"Seleziona uno dei {Sheets.Count} fogli disponibili.";
            var mapLocation = await LocationSearchService.SearchAsync($"{municipality.Name}, Italia", token);
            if (mapLocation is not null)
            {
                await JS.InvokeVoidAsync("lmeMap.showSearchResult", mapLocation.Latitude, mapLocation.Longitude, mapLocation.Label);
            }
        }
        catch (OperationCanceledException)
        {
        }
        catch (Exception error)
        {
            CatalogMessage = $"Impossibile caricare i fogli: {error.Message}";
            await JS.InvokeVoidAsync("lmeMap.showInfo", CatalogMessage);
        }
        finally
        {
            CatalogBusy = false;
            CatalogFraction = null;
        }
    }

    private async Task OnSheetChanged(ChangeEventArgs args)
    {
        SelectedSheet = args.Value?.ToString() ?? string.Empty;
        SelectedParcelNumber = string.Empty;
        Parcels = [];
        var municipality = SelectedMunicipality;
        if (municipality is null || string.IsNullOrWhiteSpace(SelectedSheet))
        {
            return;
        }

        var token = BeginCatalogWork();
        CatalogBusy = true;
        CatalogMessage = "Carico le particelle del foglio...";
        CatalogFraction = null;
        try
        {
            Parcels = await CatalogService.GetParcelsAsync(municipality, SelectedSheet, CreateProgress(), token);
            CatalogMessage = $"Seleziona una delle {Parcels.Count} particelle disponibili.";
        }
        catch (OperationCanceledException)
        {
        }
        catch (Exception error)
        {
            CatalogMessage = $"Impossibile caricare le particelle: {error.Message}";
            await JS.InvokeVoidAsync("lmeMap.showInfo", CatalogMessage);
        }
        finally
        {
            CatalogBusy = false;
            CatalogFraction = null;
        }
    }

    private Task OnParcelChanged(ChangeEventArgs args)
    {
        SelectedParcelNumber = args.Value?.ToString() ?? string.Empty;
        return Task.CompletedTask;
    }

    private async Task LocateParcel()
    {
        var municipality = SelectedMunicipality;
        var parcel = SelectedParcel;
        if (municipality is null || parcel is null)
        {
            return;
        }

        try
        {
            var label = $"{municipality.Name} - foglio {DisplaySheet(SelectedSheet)}, particella {parcel.Number}";
            CatalogBusy = true;
            CatalogMessage = "Scarico il confine dal servizio ufficiale AdE...";
            var xml = await OfficialCadastreService.GetParcelsNearAsync(parcel.Latitude, parcel.Longitude, 8);
            await JS.InvokeVoidAsync("lmeMap.displayOfficialParcel", xml, parcel.Latitude, parcel.Longitude, parcel.Number, label, true);
            ActiveTab = "map";
            await Task.Delay(30);
            await JS.InvokeVoidAsync("lmeMap.resize");
        }
        catch (Exception error)
        {
            CatalogMessage = $"Particella non visualizzata: {error.Message}";
            await JS.InvokeVoidAsync("lmeMap.showInfo", CatalogMessage);
        }
        finally
        {
            CatalogBusy = false;
        }
    }

    private async Task ToggleGps()
    {
        if (GpsActive)
        {
            await StopGps();
        }
        else
        {
            await StartGps();
        }
    }

    private async Task StartGps()
    {
        GpsActive = true;
        GpsLookupCancellation?.Cancel();
        GpsLookupCancellation?.Dispose();
        GpsLookupCancellation = new CancellationTokenSource();
        var lookupToken = GpsLookupCancellation.Token;
        try
        {
            await LocationService.StartTrackingAsync(
                location => HandleGpsLocationAsync(location, lookupToken),
                async error => await InvokeAsync(() => JS.InvokeVoidAsync("lmeMap.setGpsError", error)));
            GpsActive = LocationService.IsTracking;
        }
        catch (Exception error)
        {
            GpsActive = false;
            await JS.InvokeVoidAsync("lmeMap.setGpsError", error.Message);
        }
    }

    private async Task StopGps()
    {
        LocationService.StopTracking();
        GpsLookupCancellation?.Cancel();
        GpsLookupCancellation?.Dispose();
        GpsLookupCancellation = null;
        GpsActive = false;
        await JS.InvokeVoidAsync("lmeMap.stopGps");
    }

    private async Task HandleGpsLocationAsync(LocationSnapshot location, CancellationToken cancellationToken)
    {
        await InvokeAsync(() => JS.InvokeVoidAsync("lmeMap.setNativeGpsPosition", location));

        var now = Environment.TickCount64;
        if (now - Interlocked.Read(ref LastGpsLookupAt) < 3_500
            || Interlocked.CompareExchange(ref GpsLookupInProgress, 1, 0) != 0)
        {
            return;
        }

        Interlocked.Exchange(ref LastGpsLookupAt, now);
        try
        {
            var radius = Math.Clamp(location.Accuracy ?? 5, 2, 25);
            var xml = await OfficialCadastreService.GetParcelsNearAsync(
                location.Latitude,
                location.Longitude,
                radius,
                cancellationToken);
            await InvokeAsync(() => JS.InvokeVoidAsync(
                "lmeMap.displayOfficialParcel",
                xml,
                location.Latitude,
                location.Longitude,
                null,
                "Posizione GPS",
                false));
        }
        catch (OperationCanceledException)
        {
        }
        catch (Exception error)
        {
            await InvokeAsync(() => JS.InvokeVoidAsync(
                "lmeMap.showInfo",
                $"Aggiornamento particella GPS non disponibile: {error.GetBaseException().Message}"));
        }
        finally
        {
            Interlocked.Exchange(ref GpsLookupInProgress, 0);
        }
    }

    private IProgress<CatalogProgress> CreateProgress() => new Progress<CatalogProgress>(progress =>
    {
        _ = InvokeAsync(() =>
        {
            CatalogMessage = progress.Message;
            CatalogFraction = progress.Fraction;
            StateHasChanged();
        });
    });

    private CancellationToken BeginCatalogWork()
    {
        CancelCatalogWork();
        CatalogCancellation = new CancellationTokenSource();
        return CatalogCancellation.Token;
    }

    private void CancelCatalogWork()
    {
        CatalogCancellation?.Cancel();
        CatalogCancellation?.Dispose();
        CatalogCancellation = null;
    }

    private static string DisplaySheet(string value)
    {
        var trimmed = value.TrimStart('0');
        return string.IsNullOrEmpty(trimmed) ? "0" : trimmed;
    }

    private Task FitImportedLayers() => JS.InvokeVoidAsync("lmeMap.fitImported").AsTask();
    private Task ClearImportedLayers() => JS.InvokeVoidAsync("lmeMap.clearImported").AsTask();
    private Task AddProjectMarker() => JS.InvokeVoidAsync("lmeMap.addProjectMarker", PoiName).AsTask();

    private async Task ToggleImportParcelsOnly(ChangeEventArgs args)
    {
        ImportParcelsOnly = (bool?)args.Value == true;
        await JS.InvokeVoidAsync("lmeMap.setImportParcelOnly", ImportParcelsOnly);
    }

    private async Task ToggleImportedMeasurements(ChangeEventArgs args)
    {
        ShowImportedMeasurements = (bool?)args.Value == true;
        await JS.InvokeVoidAsync("lmeMap.setImportedMeasurementsVisible", ShowImportedMeasurements);
    }

    private async Task ToggleDrawingMeasurements(ChangeEventArgs args)
    {
        ShowDrawingMeasurements = (bool?)args.Value == true;
        await JS.InvokeVoidAsync("lmeMap.setDrawingMeasurementsVisible", ShowDrawingMeasurements);
    }

    private async Task StartMeasurementDrawing(string mode)
    {
        DrawToolsVisible = false;
        await JS.InvokeVoidAsync("lmeMap.setDrawToolsVisible", false);
        ActiveTab = "map";
        LayerPanelOpen = false;
        await Task.Delay(30);
        await JS.InvokeVoidAsync("lmeMap.resize");
        await JS.InvokeVoidAsync("lmeMap.startMeasurementDrawing", mode);
    }

    private async Task ToggleDrawTools()
    {
        DrawToolsVisible = !DrawToolsVisible;
        await JS.InvokeVoidAsync("lmeMap.setDrawToolsVisible", DrawToolsVisible);

        if (DrawToolsVisible)
        {
            await SelectTab("map");
        }
    }

    private Task ClearDrawings() => JS.InvokeVoidAsync("lmeMap.clearDrawings").AsTask();

    private async Task RefreshProjectsAsync()
    {
        try
        {
            Projects = await ProjectStorageService.GetProjectsAsync();
            if (Projects.All(project => project.Id != SelectedProjectId))
            {
                SelectedProjectId = string.Empty;
            }
            ProjectArchiveMessage = Projects.Count == 0
                ? "Nessun progetto salvato."
                : $"{Projects.Count} {(Projects.Count == 1 ? "progetto salvato" : "progetti salvati")} nell'archivio interno.";
        }
        catch (Exception error)
        {
            ProjectArchiveMessage = $"Archivio non disponibile: {error.GetBaseException().Message}";
        }
    }

    private Task SelectProject(ChangeEventArgs args)
    {
        SelectedProjectId = args.Value?.ToString() ?? string.Empty;
        return Task.CompletedTask;
    }

    private async Task SaveProject()
    {
        var name = NewProjectName.Trim();
        if (string.IsNullOrWhiteSpace(name))
        {
            await JS.InvokeVoidAsync("lmeMap.showInfo", "Inserisci il nome del progetto.");
            return;
        }

        var existing = Projects.FirstOrDefault(project =>
            string.Equals(project.Name, name, StringComparison.CurrentCultureIgnoreCase));
        if (existing is not null
            && !await JS.InvokeAsync<bool>("confirm", $"Il progetto '{existing.Name}' esiste gia. Sovrascriverlo?"))
        {
            return;
        }

        ProjectBusy = true;
        try
        {
            var snapshot = await JS.InvokeAsync<string>("lmeMap.createProjectSnapshot", IncludeCadastralParcels);
            var saved = await ProjectStorageService.SaveAsync(
                name,
                snapshot,
                IncludeCadastralParcels,
                existing?.Id);
            await RefreshProjectsAsync();
            SelectedProjectId = saved.Id;
            NewProjectName = saved.Name;
            await JS.InvokeVoidAsync(
                "lmeMap.showInfo",
                IncludeCadastralParcels
                    ? $"Progetto salvato: {saved.Name}, incluse le particelle rosse."
                    : $"Progetto salvato: {saved.Name}, senza particelle rosse.");
        }
        catch (Exception error)
        {
            await JS.InvokeVoidAsync("lmeMap.showInfo", $"Progetto non salvato: {error.GetBaseException().Message}");
        }
        finally
        {
            ProjectBusy = false;
        }
    }

    private async Task LoadProject()
    {
        var project = Projects.FirstOrDefault(item => item.Id == SelectedProjectId);
        if (project is null)
        {
            await JS.InvokeVoidAsync("lmeMap.showInfo", "Seleziona il progetto da caricare.");
            return;
        }

        ProjectBusy = true;
        try
        {
            var snapshot = await ProjectStorageService.LoadAsync(project.Id);
            await JS.InvokeVoidAsync("lmeMap.loadProjectSnapshot", snapshot, project.Name);
            NewProjectName = project.Name;
            IncludeCadastralParcels = project.IncludesCadastralParcels;
            ActiveTab = "map";
            await Task.Delay(30);
            await JS.InvokeVoidAsync("lmeMap.resize");
        }
        catch (Exception error)
        {
            await JS.InvokeVoidAsync("lmeMap.showInfo", $"Progetto non caricato: {error.GetBaseException().Message}");
        }
        finally
        {
            ProjectBusy = false;
        }
    }

    private async Task DeleteProject()
    {
        var project = Projects.FirstOrDefault(item => item.Id == SelectedProjectId);
        if (project is null)
        {
            return;
        }
        if (!await JS.InvokeAsync<bool>("confirm", $"Eliminare definitivamente il progetto '{project.Name}'?"))
        {
            return;
        }

        ProjectBusy = true;
        try
        {
            await ProjectStorageService.DeleteAsync(project.Id);
            SelectedProjectId = string.Empty;
            await RefreshProjectsAsync();
            await JS.InvokeVoidAsync("lmeMap.showInfo", $"Progetto eliminato: {project.Name}.");
        }
        catch (Exception error)
        {
            await JS.InvokeVoidAsync("lmeMap.showInfo", $"Progetto non eliminato: {error.GetBaseException().Message}");
        }
        finally
        {
            ProjectBusy = false;
        }
    }
    private Task CenterOnGps() => JS.InvokeVoidAsync("lmeMap.centerOnGps").AsTask();
    private async Task ToggleTrail(ChangeEventArgs args)
    {
        TrailEnabled = (bool?)args.Value == true;
        await JS.InvokeVoidAsync("lmeMap.toggleTrail", TrailEnabled);
    }
    private async Task ChangeBaseLayer(ChangeEventArgs args)
    {
        var requestedLayer = args.Value?.ToString() ?? "satellite";
        try
        {
            if (requestedLayer.StartsWith("google-", StringComparison.Ordinal))
            {
                if (string.IsNullOrWhiteSpace(GoogleMapsApiKey))
                {
                    await JS.InvokeVoidAsync("lmeMap.showInfo", "Inserisci e salva una chiave Google Maps Platform per usare questo sfondo.");
                    return;
                }

                await JS.InvokeVoidAsync("lmeMap.configureGoogleMaps", GoogleMapsApiKey.Trim());
            }

            if (requestedLayer.StartsWith("azure-", StringComparison.Ordinal))
            {
                if (string.IsNullOrWhiteSpace(AzureMapsSubscriptionKey))
                {
                    await JS.InvokeVoidAsync("lmeMap.showInfo", "Inserisci e salva la chiave della sottoscrizione Azure Maps.");
                    return;
                }

                await AzureMapsService.ValidateKeyAsync(AzureMapsSubscriptionKey);
                await JS.InvokeVoidAsync("lmeMap.configureAzureMaps", AzureMapsSubscriptionKey.Trim());
            }

            await JS.InvokeVoidAsync("lmeMap.setBaseLayer", requestedLayer);
            SelectedBaseLayer = requestedLayer;
        }
        catch (Exception error)
        {
            await JS.InvokeVoidAsync("lmeMap.showInfo", $"Sfondo non disponibile: {error.GetBaseException().Message}");
        }
    }

    private async Task SaveGoogleMapsApiKey()
    {
        try
        {
            if (string.IsNullOrWhiteSpace(GoogleMapsApiKey))
            {
                SecureStorage.Default.Remove("google_maps_api_key");
                await JS.InvokeVoidAsync("lmeMap.showInfo", "Chiave Google rimossa.");
                return;
            }

            GoogleMapsApiKey = GoogleMapsApiKey.Trim();
            await SecureStorage.Default.SetAsync("google_maps_api_key", GoogleMapsApiKey);
            await JS.InvokeVoidAsync("lmeMap.configureGoogleMaps", GoogleMapsApiKey);
            await JS.InvokeVoidAsync("lmeMap.showInfo", "Chiave Google salvata sul dispositivo.");
        }
        catch (Exception error)
        {
            await JS.InvokeVoidAsync("lmeMap.showInfo", $"Chiave Google non salvata: {error.Message}");
        }
    }

    private async Task SaveAzureMapsKey()
    {
        try
        {
            if (string.IsNullOrWhiteSpace(AzureMapsSubscriptionKey))
            {
                SecureStorage.Default.Remove("azure_maps_subscription_key");
                await JS.InvokeVoidAsync("lmeMap.clearAzureMaps");
                if (SelectedBaseLayer.StartsWith("azure-", StringComparison.Ordinal))
                {
                    SelectedBaseLayer = "satellite";
                }
                await JS.InvokeVoidAsync("lmeMap.showInfo", "Chiave Azure Maps rimossa.");
                return;
            }

            AzureMapsSubscriptionKey = AzureMapsSubscriptionKey.Trim();
            await AzureMapsService.ValidateKeyAsync(AzureMapsSubscriptionKey);
            await SecureStorage.Default.SetAsync("azure_maps_subscription_key", AzureMapsSubscriptionKey);
            await JS.InvokeVoidAsync("lmeMap.configureAzureMaps", AzureMapsSubscriptionKey);
            await JS.InvokeVoidAsync("lmeMap.showInfo", "Chiave Azure Maps valida e salvata sul dispositivo.");
        }
        catch (Exception error)
        {
            await JS.InvokeVoidAsync("lmeMap.showInfo", $"Chiave Azure Maps non salvata: {error.GetBaseException().Message}");
        }
    }
    private Task ChangeCadastreOpacity(ChangeEventArgs args) => JS.InvokeVoidAsync("lmeMap.setCadastreOpacity", args.Value?.ToString()).AsTask();

    private async Task ToggleCadastreLayer(CadastralLayer layer, ChangeEventArgs args)
    {
        layer.Enabled = args.Value is true;
        await JS.InvokeVoidAsync("lmeMap.toggleCadastreLayer", layer.Key, layer.Enabled);
    }

    private async Task ExportCadastralImage()
    {
        ActiveTab = "map";
        LayerPanelOpen = false;
        await Task.Delay(30);
        await JS.InvokeVoidAsync("lmeMap.resize");
        await JS.InvokeVoidAsync("lmeMap.exportCadastreView");
    }

    private Task ClearSelectedParcels() => JS.InvokeVoidAsync("lmeMap.clearSelectedParcels").AsTask();

    private Task ClearMapElements() => JS.InvokeVoidAsync("lmeMap.clearMapElements").AsTask();

    private Task OpenOfficialGeoportal() => Microsoft.Maui.ApplicationModel.Launcher.Default.OpenAsync(
        new Uri("https://geoportale.cartografia.agenziaentrate.gov.it/"));

    private Task OpenOfficialReservedArea() => Microsoft.Maui.ApplicationModel.Launcher.Default.OpenAsync(
        new Uri("https://www.agenziaentrate.gov.it/portale/area-riservata"));

    private sealed class CadastralLayer(string key, string name, bool enabled, string detail = "")
    {
        public string Key { get; } = key;
        public string Name { get; } = name;
        public bool Enabled { get; set; } = enabled;
        public string Detail { get; } = detail;
    }

    public ValueTask DisposeAsync()
    {
        CancelCatalogWork();
        LocationService.StopTracking();
        GpsLookupCancellation?.Cancel();
        GpsLookupCancellation?.Dispose();
        return ValueTask.CompletedTask;
    }
}