using Core.Entities;

namespace Core.Printing;

/// <summary>
/// Ranking-index style badges: colored rank dot plus a short label.
/// Student pages list ranked events; event pages list students who ranked them.
/// </summary>
public static class PrintRankBadgeHtml
{
    public static string ForStudentEvents(IEnumerable<StudentEventRanking>? rankings)
    {
        if (rankings is null)
            return string.Empty;

        var badges = rankings
            .Where(r => r.Rank is >= 1 and <= StudentEventRanking.MaxRank)
            .OrderBy(r => r.Rank)
            .Select(EventBadge)
            .ToList();

        return Wrap(badges);
    }

    public static string ForEventStudents(IEnumerable<StudentEventRanking>? rankings)
    {
        if (rankings is null)
            return string.Empty;

        var badges = rankings
            .Where(r => r.Student is not null && r.Rank is >= 1 and <= StudentEventRanking.MaxRank)
            .OrderBy(r => r.Rank)
            .ThenByDescending(r => r.Student.Grade + r.Student.TsaYear)
            .Select(r => StudentBadge(r.Student.FirstName, r.Rank))
            .ToList();

        return Wrap(badges);
    }

    internal static string EventBadge(StudentEventRanking ranking)
    {
        var evt = ranking.EventDefinition;
        var label = !string.IsNullOrWhiteSpace(evt?.ShortName)
            ? evt.ShortName
            : evt?.Name;
        var attributes = EventAttributeMarks.For(evt);
        var attrsHtml = string.IsNullOrEmpty(attributes)
            ? string.Empty
            : $"<span class=\"print-event-attrs\">{PrintTokenMap.EscapeHtml(attributes)}</span>";

        return Badge(ranking.Rank, PrintTokenMap.EscapeHtml(label), attrsHtml);
    }

    internal static string StudentBadge(string? firstName, int rank) =>
        Badge(rank, PrintTokenMap.EscapeHtml(firstName), string.Empty);

    private static string Badge(int rank, string labelHtml, string extraHtml)
    {
        var extra = string.IsNullOrEmpty(extraHtml) ? string.Empty : $" {extraHtml}";
        return
            $"<span class=\"print-rank-badge\">" +
            $"<span class=\"print-rank-dot event-rank-{rank}\"></span> " +
            $"{labelHtml}{extra}" +
            "</span>";
    }

    public static string Legend()
    {
        var marks = EventAttributeMarks.LegendItems
            .Select(mark =>
                "<span class=\"print-legend-mark\">" +
                $"<span class=\"print-event-attrs\">{PrintTokenMap.EscapeHtml(mark.Symbol)}</span> " +
                PrintTokenMap.EscapeHtml(mark.Label) +
                "</span>");

        return
            "<div class=\"print-badge-legend\">" +
            $"<div class=\"print-attr-legend\">{string.Join(" &middot; ", marks)}</div>" +
            "</div>";
    }

    private static string Wrap(IReadOnlyList<string> badges, string separator = " ")
    {
        if (badges.Count == 0)
            return string.Empty;

        return $"<div class=\"print-rank-badges\">{string.Join(separator, badges)}</div>";
    }
}