@page "/"
@inject IJSRuntime JS
@inject PreciseLocationService LocationService
@inject CadastralCatalogService CatalogService
@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>
            <button class="toolbar-button" @onclick='() => SelectTab(ActiveTab == "search" ? "map" : "search")'>Cerca</button>
        </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>

        <div class="gps-overlay">
            <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>
                        <div class="button-row">
                            <button @onclick="FitImportedLayers">Inquadra</button>
                            <button class="secondary-command" @onclick="ClearImportedLayers">Pulisci</button>
                        </div>

                        <h2>Progetti e POI</h2>
                        <label>
                            Nome
                            <input @bind="ProjectName" @bind:event="oninput" placeholder="Nome progetto o POI" />
                        </label>
                        <button class="primary-command" @onclick="AddProjectMarker">Aggiungi POI al centro mappa</button>
                        <div class="button-row">
                            <button @onclick="EnableDrawTools">Disegna</button>
                            <button @onclick="SaveWorkspace">Salva</button>
                            <button @onclick="LoadWorkspace">Carica</button>
                        </div>
                    </section>
                }
                else if (ActiveTab == "settings")
                {
                    <section class="panel-content">
                        <h2>Visualizzazione</h2>
                        <label>
                            Sfondo
                            <select @onchange="ChangeBaseLayer">
                                <option value="satellite">Satellite</option>
                                <option value="osm">Strade</option>
                            </select>
                        </label>
                        <label>
                            Trasparenza catasto
                            <input type="range" min="0" max="1" step="0.05" value="0.75" @onchange="ChangeCadastreOpacity" />
                        </label>
                        <div class="layer-toggles">
                            @foreach (var layer in CadastralLayers)
                            {
                                <label>
                                    <input type="checkbox" checked="@layer.Enabled" @onchange="(args) => ToggleCadastreLayer(layer.Key, args)" />
                                    @layer.Name
                                </label>
                            }
                        </div>

                        <h2>GPS e percorso</h2>
                        <label class="toggle-line">
                            <input type="checkbox" checked @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">Apri 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>

        <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 ProjectName { get; set; } = string.Empty;
    private string Status { get; set; } = "online";
    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 CancellationTokenSource? CatalogCancellation { get; set; }

    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 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", "Particelle", true),
        new("codice_plla", "Numeri particelle", true),
        new("CP.CadastralZoning", "Fogli", true),
        new("fabbricati", "Fabbricati", true),
        new("strade", "Strade", false),
        new("acque", "Acque", false)
    ];

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

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

    private async Task SelectTab(string tab)
    {
        ActiveTab = tab;
        await Task.Delay(30);
        await JS.InvokeVoidAsync("lmeMap.resize");
    }

    private async Task SearchLocation()
    {
        try
        {
            await JS.InvokeVoidAsync("lmeMap.search", SearchText);
            ActiveTab = "map";
        }
        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.";
            await JS.InvokeVoidAsync("lmeMap.search", $"{municipality.Name}, Italia");
        }
        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}";
            await JS.InvokeVoidAsync("lmeMap.locateParcelByPoint", parcel.Latitude, parcel.Longitude, parcel.Number, label);
            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);
        }
    }

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

    private async Task StartGps()
    {
        GpsActive = true;
        try
        {
            await LocationService.StartTrackingAsync(
                async location => await InvokeAsync(() => JS.InvokeVoidAsync("lmeMap.setNativeGpsPosition", location)),
                async error => await InvokeAsync(() => JS.InvokeVoidAsync("lmeMap.setGpsError", error)));
        }
        catch (Exception error)
        {
            GpsActive = false;
            await JS.InvokeVoidAsync("lmeMap.setGpsError", error.Message);
        }
    }

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

    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", ProjectName).AsTask();
    private Task EnableDrawTools() => JS.InvokeVoidAsync("lmeMap.enableDrawTools").AsTask();
    private Task SaveWorkspace() => JS.InvokeVoidAsync("lmeMap.saveWorkspace").AsTask();
    private Task LoadWorkspace() => JS.InvokeVoidAsync("lmeMap.loadWorkspace").AsTask();
    private Task CenterOnGps() => JS.InvokeVoidAsync("lmeMap.centerOnGps").AsTask();
    private Task ToggleTrail(ChangeEventArgs args) => JS.InvokeVoidAsync("lmeMap.toggleTrail", (bool?)args.Value == true).AsTask();
    private Task ChangeBaseLayer(ChangeEventArgs args) => JS.InvokeVoidAsync("lmeMap.setBaseLayer", args.Value?.ToString()).AsTask();
    private Task ChangeCadastreOpacity(ChangeEventArgs args) => JS.InvokeVoidAsync("lmeMap.setCadastreOpacity", args.Value?.ToString()).AsTask();
    private Task ToggleCadastreLayer(string layer, ChangeEventArgs args) => JS.InvokeVoidAsync("lmeMap.toggleCadastreLayer", layer, (bool?)args.Value == true).AsTask();
    private Task ExportCadastralImage() => JS.InvokeVoidAsync("lmeMap.exportCadastreView").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 record CadastralLayer(string Key, string Name, bool Enabled);

    public ValueTask DisposeAsync()
    {
        CancelCatalogWork();
        LocationService.StopTracking();
        return ValueTask.CompletedTask;
    }
}