@page "/meeting-schedule/history"
@attribute [Authorize]
@using Core.Entities
@using Microsoft.EntityFrameworkCore
@using WebApp.Components.Shared.Components
@using WebApp.Services
@inject ITeamMeetingHistoryService TeamMeetingHistoryService
@inject AppDbContext Context
@inject IDialogService DialogService
@inject ISnackbar Snackbar
@inject IConfiguration Configuration
@inject IMeetingScheduleDataService DataService
@inject IMeetingScheduleStateService StateService
@inject NavigationManager NavigationManager
@implements IAsyncDisposable

<PageHeader Title="Team Meeting Schedule History">
    <ActionButtons>
        <MudButton StartIcon="@Icons.Material.Filled.Add"
                  Variant="Variant.Outlined"
                  Color="Color.Primary"
                  Href="/meeting-schedule">
            Back to Schedule
        </MudButton>
    </ActionButtons>
</PageHeader>

<MudPaper Elevation="2" Class="pa-3 pa-md-6 mt-4">
    @if (_isLoading)
    {
        <MudProgressLinear Color="Color.Primary" Indeterminate="true" Class="my-4" />
    }
    else
    {
        <MudStack Spacing="3">
            @if (_meetingHistories.Any())
            {
                <MudPaper Elevation="1" Class="pa-3" Style="overflow-x: auto; -webkit-overflow-scrolling: touch;">
                    <table class="history-grid-table" style="min-width: max-content; width: 100%; border-collapse: collapse;">
                        <colgroup>
                            <col style="width: 72px;" />
                            <col style="width: 40px;" />
                            @for (var c = 0; c < _allTeams.Count; c++)
                            {
                                <col style="width: 28px;" />
                            }
                        </colgroup>
                        <thead>
                            <tr>
                                <th class="history-cell history-cell-date">
                                    <span class="mud-typography mud-typography-caption">Date</span>
                                </th>
                                <th class="history-cell history-cell-actions">
                                    <span class="mud-typography mud-typography-caption" style="writing-mode: vertical-rl; text-orientation: mixed; transform: rotate(180deg);">Actions</span>
                                </th>
                                @{
                                    var teamIndex = 0;
                                }
                                @foreach (var team in _allTeams)
                                {
                                    var isEven = teamIndex % 2 == 0;
                                    var colClass = isEven ? "history-cell history-cell-col-even" : "history-cell history-cell-col-odd";
                                    <th class="@colClass">
                                        <span class="mud-typography mud-typography-caption" style="writing-mode: vertical-rl; text-orientation: mixed; transform: rotate(180deg);">@team.ToString()</span>
                                    </th>
                                    teamIndex++;
                                }
                            </tr>
                            <tr>
                                <th class="history-cell history-cell-date  history-cell-times-met">Times Met</th>
                                <th class="history-cell history-cell-actions "></th>
                                @{
                                    var summaryTeamIndex = 0;
                                }
                                @foreach (var team in _allTeams)
                                {
                                    var timesMet = GetTimesMetForTeam(team);
                                    var isEven = summaryTeamIndex % 2 == 0;
                                    var colClass = isEven ? "history-cell history-cell-col-even history-cell-times-met" : "history-cell history-cell-col-odd history-cell-times-met";
                                    <th class="@colClass">@timesMet</th>
                                    summaryTeamIndex++;
                                }
                            </tr>
                        </thead>
                        <tbody>
                            @{
                                var rowIndex = 0;
                            }
                            @foreach (var history in _meetingHistories)
                            {
                                var rowTeamIndex = 0;
                                var rowClass = rowIndex % 2 == 0 ? "history-row-even" : "history-row-odd";
                                <tr class="@rowClass">
                                    <td class="history-cell history-cell-date ">
                                        <MudButton Variant="Variant.Text"
                                                  Color="Color.Primary"
                                                  Size="Size.Small"
                                                  OnClick="@(() => ViewMeetingDetails(history))"
                                                  Style="text-transform: none; padding: 0 2px; min-width: unset;">
                                            @history.MeetingDate.ToString("MM/dd/yy")
                                        </MudButton>
                                    </td>
                                    <td class="history-cell history-cell-actions">
                                        <MudTooltip Text="Load into Planner">
                                            <MudIconButton Icon="@Icons.Material.Filled.Upload"
                                                          Size="Size.Small"
                                                          Color="Color.Secondary"
                                                          OnClick="@(() => LoadMeetingIntoPlanner(history))"
                                                          Variant="Variant.Text"
                                                          Style="padding: 2px;" />
                                        </MudTooltip>
                                    </td>
                                    @foreach (var team in _allTeams)
                                    {
                                        var met = TeamMetOnDate(history, team);
                                        var isEven = rowTeamIndex % 2 == 0;
                                        var colClass = isEven ? "history-cell history-cell-col-even" : "history-cell history-cell-col-odd";
                                        <td class="@colClass">
                                            @if (met)
                                            {
                                                <span class="mud-typography mud-typography-body1" style="font-weight: bold;">×</span>
                                            }
                                        </td>
                                        rowTeamIndex++;
                                    }
                                </tr>
                                rowIndex++;
                            }
                        </tbody>
                    </table>
                </MudPaper>
            }
            else
            {
                <MudAlert Severity="Severity.Info">No meeting history found. Save a meeting schedule to get started.</MudAlert>
            }
        </MudStack>
    }
</MudPaper>

<style>
    .history-grid-table {
        --history-border: 1px solid var(--mud-palette-divider);
        --history-shade: var(--mud-palette-background-grey);
    }
    .history-grid-table th,
    .history-grid-table td {
        padding: 2px 4px;
        border-right: var(--history-border);
        border-bottom: var(--history-border);
        vertical-align: middle;
    }
    .history-grid-table thead th {
        border-top: var(--history-border);
        background-color: var(--mud-palette-surface);
    }
    .history-grid-table thead .history-cell-col-odd {
        background-color: var(--mud-palette-surface);
    }
    .history-grid-table thead th:first-child,
    .history-grid-table tbody td:first-child {
        border-left: var(--history-border);
    }
    .history-grid-table .history-cell-date {
        padding: 2px 4px;
        text-align: left;
        min-width: 72px;
    }
    .history-grid-table .history-cell-actions {
        padding: 2px;
        text-align: center;
        min-width: 40px;
    }
    .history-grid-table thead .history-cell-col-even {
        background-color: var(--history-shade);
    }
    .history-grid-table .history-cell-times-met {
        font-weight: bold;
        background-color: var(--history-shade);
    }
    .history-grid-table tbody .history-row-odd td {
        background-color: var(--history-shade);
    }
    .history-grid-table tbody .history-row-even td.history-cell-col-even,
    .history-grid-table tbody .history-row-odd td.history-cell-col-even {
        background-color: var(--history-shade);
    }
    .history-grid-table tbody .history-row-odd td.history-cell-col-odd {
        background-color: var(--history-shade);
    }
</style>

@code {
    private List<TeamMeetingHistory> _meetingHistories = [];
    private List<Team> _allTeams = [];
    private Dictionary<int, int> _timesMetDict = new();
    private bool _isLoading = true;
    private CancellationTokenSource? _cancellationTokenSource;
    private bool _isDisposed = false;

    protected override void OnInitialized()
    {
        _cancellationTokenSource = new CancellationTokenSource();
    }

    protected override async Task OnInitializedAsync()
    {
        await LoadData();
    }

    private async Task LoadData()
    {
        if (_isDisposed) return;

        try
        {
            _isLoading = true;
            StateHasChanged();

            // Load all teams for columns
            _allTeams = await Context.Teams
                .AsNoTracking()
                .Include(t => t.Event)
                .OrderBy(t => t.Event.Name)
                .ThenBy(t => t.Identifier)
                .ToListAsync();

            // Load meeting histories
            await RefreshMeetingHistories();

            // Calculate times met
            CalculateTimesMet();
        }
        catch (TaskCanceledException)
        {
            // Component was disposed, ignore
        }
        catch (JSDisconnectedException)
        {
            // JS connection lost, ignore
        }
        catch (Exception ex)
        {
            if (!_isDisposed)
            {
                Snackbar.Add($"Error loading meeting history: {ex.Message}", Severity.Error);
            }
        }
        finally
        {
            if (!_isDisposed)
            {
                _isLoading = false;
                StateHasChanged();
            }
        }
    }

    private async Task RefreshMeetingHistories()
    {
        _meetingHistories = (await TeamMeetingHistoryService.GetMeetingHistoriesAsync()).ToList();

        // Extract all unique teams from meeting histories and merge with all teams
        var teamsInHistory = _meetingHistories
            .SelectMany(mh => mh.Teams)
            .DistinctBy(t => t.Id)
            .ToList();

        // Merge with all teams, ensuring all teams are included
        var allTeamIds = _allTeams.Select(t => t.Id).ToHashSet();
        var newTeams = teamsInHistory.Where(t => !allTeamIds.Contains(t.Id)).ToList();
        _allTeams = _allTeams.Concat(newTeams).OrderBy(t => t.Event?.Name ?? "").ThenBy(t => t.Identifier).ToList();
    }

    private void CalculateTimesMet()
    {
        _timesMetDict.Clear();

        foreach (var team in _allTeams)
        {
            _timesMetDict[team.Id] = 0;
        }

        foreach (var history in _meetingHistories)
        {
            var teamIds = history.Teams.Select(t => t.Id).ToHashSet();
            foreach (var teamId in teamIds)
            {
                if (_timesMetDict.ContainsKey(teamId))
                {
                    _timesMetDict[teamId]++;
                }
            }
        }
    }

    private int GetTimesMetForTeam(Team team)
    {
        return _timesMetDict.GetValueOrDefault(team.Id, 0);
    }

    private bool TeamMetOnDate(TeamMeetingHistory history, Team team)
    {
        return history.Teams.Any(t => t.Id == team.Id);
    }

    private async Task ViewMeetingDetails(TeamMeetingHistory history)
    {
        var parameters = new DialogParameters
        {
            ["MeetingHistoryId"] = history.Id
        };

        var options = new DialogOptions
        {
            MaxWidth = MaxWidth.Large,
            FullWidth = true,
            CloseButton = true
        };

        var dialog = await DialogService.ShowAsync<MeetingHistoryDetailDialog>("Meeting Details", parameters, options);
        var result = await dialog.Result;

        if (!result.Canceled)
        {
            // Refresh data if meeting was updated or deleted
            await RefreshMeetingHistories();
            CalculateTimesMet();
            if (!_isDisposed)
            {
                StateHasChanged();
            }
        }
    }

    private async Task LoadMeetingIntoPlanner(TeamMeetingHistory history)
    {
        if (_isDisposed) return;

        try
        {
            // Get all teams and students from database
            var allTeams = await DataService.LoadTeamsAsync();
            var allStudents = await DataService.LoadStudentsAsync();

            // Match teams from history to all teams by ID for reference equality
            var historyTeamIds = history.Teams.Select(t => t.Id).ToHashSet();
            var scheduledTeams = allTeams.Where(t => historyTeamIds.Contains(t.Id));

            // Calculate absent students (all students not in the meeting history's student list)
            var presentStudentIds = history.Students.Select(s => s.Id).ToHashSet();
            var absentStudents = allStudents.Where(s => !presentStudentIds.Contains(s.Id));

            // Save state to localStorage
            await StateService.SaveScheduledTeamsAsync(scheduledTeams);
            await StateService.SaveAbsentStudentsAsync(absentStudents);
            // Clear extended teams and excluded students when loading from history
            await StateService.SaveExtendedTeamsAsync([]);
            await StateService.SaveExcludedStudentsAsync(new Dictionary<(int teamId, int timeSlotIndex, int studentId), bool>());

            // Navigate to planner
            NavigationManager.NavigateTo("/meeting-schedule");

            if (!_isDisposed)
            {
                Snackbar.Add($"Loaded meeting from {history.MeetingDate:MM/dd/yyyy} into planner", Severity.Success);
            }
        }
        catch (TaskCanceledException)
        {
            // Component was disposed, ignore
        }
        catch (JSDisconnectedException)
        {
            // JS connection lost, ignore
        }
        catch (Exception ex)
        {
            if (!_isDisposed)
            {
                Snackbar.Add($"Error loading meeting into planner: {ex.Message}", Severity.Error);
            }
        }
    }

    public async ValueTask DisposeAsync()
    {
        if (!_isDisposed)
        {
            _isDisposed = true;
            _cancellationTokenSource?.Cancel();
            _cancellationTokenSource?.Dispose();
            _cancellationTokenSource = null;
        }
        await ValueTask.CompletedTask;
    }
}