using System.Collections.ObjectModel;
using ClaudeDo.Data;
using ClaudeDo.Data.Models;
using ClaudeDo.Data.Repositories;
using ClaudeDo.Ui.Localization;
using ClaudeDo.Ui.Services;
using ClaudeDo.Ui.ViewModels.Agent;
using ClaudeDo.Ui.ViewModels.Modals.Settings;
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using Microsoft.EntityFrameworkCore;

namespace ClaudeDo.Ui.ViewModels.Modals;

// UI-only projection of TicketProjectDto for the ComboBox display text, plus a synthetic
// Id=0 "none" entry (mirrors AgentConfigEditorViewModel's "(none)" AgentInfo placeholder).
public sealed record TicketProjectOption(int Id, string Display);

public sealed partial class ListSettingsModalViewModel : ViewModelBase
{
    private readonly IWorkerClient _worker;
    private readonly IDbContextFactory<ClaudeDoDbContext> _dbFactory;

    public string ListId { get; set; } = "";

    // True after the list was deleted, so the caller reloads the list nav instead of refreshing the row.
    public bool Deleted { get; private set; }

    // False when the modal closed via Cancel or the window chrome — CreateListAsync uses this to
    // roll the pre-created row back instead of leaving an untitled empty list behind.
    public bool Saved { get; private set; }

    // Wired by the view to prompt yes/no before deleting and to surface a blocking-FK error.
    public Func<string, Task<bool>>? ConfirmAsync { get; set; }
    public Func<string, Task>? ShowErrorAsync { get; set; }

    // Mirrors UsageMonitorModalViewModel.ErrorReported — the caller wires this into FlashFooterError.
    public event Action<string>? ErrorReported;

    [ObservableProperty] private string _name = "";
    [ObservableProperty] private string _workingDir = "";
    [ObservableProperty] private string _defaultCommitType = CommitTypeRegistry.DefaultType;
    // A manual list holds reminders: tasks created here start out manual (TaskEntity.IsManual).
    [ObservableProperty] private bool _isManual;
    // When true the project's .claudedo/ findings store is committed with the repo; when false it
    // is kept out of git via .git/info/exclude (see FindingsStore / ListEntity.FindingsTracked).
    [ObservableProperty] private bool _findingsTracked;
    // Optional post-merge verification command (build/test), run in WorkingDir after a merge
    // lands; a non-zero exit keeps the task out of Done instead of silently reporting merged.
    [ObservableProperty] private string _verifyCommand = "";
    // Per-list opt-in for PowerUse. A handler run on this list only goes unattended (no questions,
    // harvests new work, longer handoff chain) when this AND the global switch in the usage monitor
    // are both on. Off by default — the global switch alone must never change a list's behaviour.
    [ObservableProperty] private bool _powerUseAllowed;
    // Dropdown hidden entirely when no ticket-system base URL is configured (Settings → Files tab).
    // Icon key into the UI icon library (IconKeyConverter -> "Icon.<key>" StreamGeometry).
    [ObservableProperty] private string _icon = DefaultIcon;
    [ObservableProperty] private bool _ticketsAvailable;
    [ObservableProperty] private TicketProjectOption? _selectedTicketProject;
    public ObservableCollection<TicketProjectOption> TicketProjects { get; } = new();

    // Gates Save/Delete while the core fields (name/agent/verify command) are still loading, so a
    // save can't land before they're populated and clobber the list_config row with blanks. Ticket
    // projects load separately (see LoadTicketProjectsAsync) and are NOT covered by this — Save's
    // own tri-state handles that case instead.
    [ObservableProperty]
    [NotifyCanExecuteChangedFor(nameof(SaveCommand))]
    [NotifyCanExecuteChangedFor(nameof(DeleteCommand))]
    private bool _isLoading;

    // Set when the core load (name/agent/verify command) threw — keeps Save gated even after
    // IsLoading resets to false in LoadAsync's finally, so a failed load can't clobber the
    // stored config with blank fields.
    private bool _loadFailed;

    // True once GetTicketProjectsAsync has completed successfully for the current load — Save
    // only writes an explicit TicketProjectId when this is true, so a slow/unreachable ticket
    // system leaves the stored link untouched instead of wiping it to "none".
    private bool _ticketProjectsLoaded;

    public ObservableCollection<string> CommitTypeOptions { get; } = new(CommitTypeRegistry.Types);

    public const string DefaultIcon = "Folder";

    // Curated subset of the Icon.* geometry library in IslandStyles.axaml — window chrome and
    // pure stroke icons (PathIcon fills, so those render invisible) are deliberately left out.
    // Grouped by theme so the picker grid reads in rows; every entry needs a matching
    // "Icon.<key>" StreamGeometry or it renders as an empty slot.
    public static readonly string[] IconOptions =
    [
        // general
        "Folder", "Star", "Sun", "Calendar", "Clock", "Inbox", "Mail", "Text", "Search", "Grid",
        // dev
        "Code", "Terminal", "Database", "Server", "Chip", "Bolt", "Wand", "Flask", "Shield",
        // status / flow
        "Activity", "Eye", "Check", "Warning", "Chart", "Rocket", "Bulb", "Broom", "AgentSuggested", "Settings",
        // things
        "Box", "Truck", "MapPin", "Camera", "Image", "Barcode", "Skull",
    ];

    public ObservableCollection<string> Icons { get; } = new(IconOptions);

    // The shared agent-config editor (Model / MaxTurns / SystemPrompt / AgentFile),
    // scoped to this list (list → global inheritance).
    public AgentConfigEditorViewModel Agent { get; }

    public Action? CloseAction { get; set; }

    public ListSettingsModalViewModel(IWorkerClient worker, IDbContextFactory<ClaudeDoDbContext> dbFactory)
    {
        _worker = worker;
        _dbFactory = dbFactory;
        Agent = new AgentConfigEditorViewModel(worker, AgentConfigScope.List);
    }

    // Fires the load without blocking the caller, so the modal window can be shown right away
    // instead of appearing only after seven serial hub round-trips (one of them a 10s-timeout
    // ticket-system HTTP call) have finished — same pattern as UsageMonitorModalViewModel.BeginLoad.
    public void BeginLoad(
        string listId,
        string name,
        string? workingDir,
        string defaultCommitType,
        bool isManual = false,
        bool findingsTracked = false,
        string? icon = null)
        => _ = LoadAsync(listId, name, workingDir, defaultCommitType, isManual, findingsTracked, icon);

    public async Task LoadAsync(
        string listId,
        string name,
        string? workingDir,
        string defaultCommitType,
        bool isManual = false,
        bool findingsTracked = false,
        string? icon = null,
        CancellationToken ct = default)
    {
        ListConfigDto? cfg = null;
        IsLoading = true;
        _loadFailed = false;
        try
        {
            ListId = listId;
            Name = name;
            IsManual = isManual;
            FindingsTracked = findingsTracked;
            // An unknown/legacy key would leave the picker with no selection and silently reset the
            // icon on the next save — fall back to the default instead.
            Icon = IconOptions.Contains(icon) ? icon! : DefaultIcon;
            WorkingDir = workingDir ?? "";
            DefaultCommitType = string.IsNullOrWhiteSpace(defaultCommitType) ? CommitTypeRegistry.DefaultType : defaultCommitType;

            await Agent.LoadForListAsync(listId, ct);
            cfg = Agent.LastLoadedListConfig;
            VerifyCommand = cfg?.VerifyCommand ?? "";
            PowerUseAllowed = cfg?.PowerUseAllowed ?? false;
        }
        catch (Exception ex)
        {
            // BeginLoad fires this without awaiting it — catching here (instead of letting it
            // propagate) turns what would be an unobserved task exception, with the modal stuck
            // open and every field blank, into a reported error and a locked Save button.
            _loadFailed = true;
            ErrorReported?.Invoke(Loc.T("vm.listSettings.loadFailed", ex.Message));
        }
        finally { IsLoading = false; }

        if (_loadFailed) return;

        // Deliberately NOT awaited: an unreachable ticket system (10s HTTP timeout) must not hold
        // up the rest of the modal. The dropdown just stays empty until this finishes.
        _ = LoadTicketProjectsAsync(cfg?.TicketProjectId);
    }

    private async Task LoadTicketProjectsAsync(int? existingTicketProjectId)
    {
        _ticketProjectsLoaded = false;
        TicketProjects.Clear();
        try
        {
            var ticketSettings = TicketSettingsTabViewModel.FeatureEnabled
                ? await _worker.GetTicketSettingsAsync()
                : null;
            TicketsAvailable = !string.IsNullOrWhiteSpace(ticketSettings?.ApiBaseUrl);
            if (!TicketsAvailable)
            {
                SelectedTicketProject = null;
                return;
            }

            TicketProjects.Add(new TicketProjectOption(0, Loc.T("vm.listSettings.ticketProjectNone")));
            foreach (var p in await _worker.GetTicketProjectsAsync())
                TicketProjects.Add(new TicketProjectOption(p.Id, $"{p.DepartmentName} / {p.Title}"));

            SelectedTicketProject = existingTicketProjectId is int id
                ? TicketProjects.FirstOrDefault(t => t.Id == id) ?? TicketProjects[0]
                : TicketProjects[0];
            _ticketProjectsLoaded = true;
        }
        catch (Exception ex)
        {
            // Ticket system unreachable/slow — leave the dropdown as-is. Save's tri-state (below)
            // skips writing TicketProjectId when _ticketProjectsLoaded is false, so the stored
            // link survives instead of being wiped to "none".
            ErrorReported?.Invoke(Loc.T("vm.listSettings.ticketProjectsLoadFailed", ex.Message));
        }
    }

    private bool CanSave() => !IsLoading && !_loadFailed;
    private bool CanDelete() => !IsLoading;

    [RelayCommand(CanExecute = nameof(CanSave))]
    private async Task SaveAsync()
    {
        await _worker.UpdateListAsync(new UpdateListDto(
            ListId,
            string.IsNullOrWhiteSpace(Name) ? Loc.T("vm.listSettings.untitled") : Name,
            string.IsNullOrWhiteSpace(WorkingDir) ? null : WorkingDir,
            DefaultCommitType,
            IsManual,
            FindingsTracked,
            Icon));

        // Tri-state: dropdown never shown (no base URL), or ticket projects failed/never loaded
        // (e.g. an unreachable ticket system) -> null, leave the stored link alone. Dropdown shown
        // and loaded -> always an explicit value, 0 for "— none —" to actively clear it. Never
        // null in that case, or an explicit unlink would silently fail to reach the worker.
        var ticketProjectId = TicketsAvailable && _ticketProjectsLoaded ? (SelectedTicketProject?.Id ?? 0) : (int?)null;

        // Always explicit (never null) — this modal owns the checkbox, so unchecking it has to reach
        // the worker as a real false rather than a "leave it alone".
        await Agent.SaveAsync(
            string.IsNullOrWhiteSpace(VerifyCommand) ? null : VerifyCommand,
            ticketProjectId,
            PowerUseAllowed);

        Saved = true;
        CloseAction?.Invoke();
    }

    [RelayCommand(CanExecute = nameof(CanDelete))]
    private async Task DeleteAsync()
    {
        var displayName = string.IsNullOrWhiteSpace(Name) ? Loc.T("vm.listSettings.untitled") : Name;
        if (ConfirmAsync is not null)
        {
            var ok = await ConfirmAsync($"Delete list \"{displayName}\" and all its tasks? This cannot be undone.");
            if (!ok) return;
        }

        try
        {
            await using var ctx = await _dbFactory.CreateDbContextAsync();
            var lists = new ListRepository(ctx);
            await lists.DeleteAsync(ListId);
        }
        catch (Exception ex) when (
            (ex is Microsoft.Data.Sqlite.SqliteException
                || ex.InnerException is Microsoft.Data.Sqlite.SqliteException)
            && (ex.Message.Contains("FOREIGN KEY", StringComparison.OrdinalIgnoreCase)
                || ex.InnerException?.Message.Contains("FOREIGN KEY", StringComparison.OrdinalIgnoreCase) == true))
        {
            if (ShowErrorAsync is not null)
                await ShowErrorAsync("This list has planning sessions with child tasks. Discard those first, then delete the list.");
            return;
        }

        Deleted = true;
        CloseAction?.Invoke();
    }

    [RelayCommand]
    private void Cancel() => CloseAction?.Invoke();
}