using System.Text;
using Vanguard.Rules.Cards;
using YamlDotNet.Serialization;
using YamlDotNet.Serialization.NamingConventions;

namespace Vanguard.Content.Translations;

public sealed class TranslationFile
{
    public int Version { get; set; } = 1;
    public List<TranslationEntry> Cards { get; set; } = new();
}

public sealed class TranslationEntry
{
    public string NameId { get; set; } = string.Empty;
    public string NameEn { get; set; } = string.Empty;

    /// <summary>Английский текст с токенами вместо иконок. Источник для перевода.</summary>
    public string? Template { get; set; }

    public string? TextRu { get; set; }
}

public static class TranslationYaml
{
    private const string Header =
        """
        # Русские тексты карт.
        #
        # Имена карт остаются английскими — переводим только текст эффекта.
        # Заполняйте только textRu. Остальные поля не меняйте.
        # Токены в фигурных скобках — это иконки: {auto}, {cb:3}, {vcrc}, {clan:kagero}.
        # Их нужно сохранить в textRu ровно в таком же количестве, иначе проверка не пройдёт.
        # Список всех токенов — content/keywords.yaml.
        #
        # Проверка: dotnet run --project server/src/Vanguard.Cli -- translations check

        """;

    public static void Write(TranslationFile file, string path)
    {
        var dir = Path.GetDirectoryName(path);
        if (!string.IsNullOrEmpty(dir))
            Directory.CreateDirectory(dir);

        var sb = new StringBuilder();
        sb.Append(Header.ReplaceLineEndings("\n"));
        sb.Append("version: ").Append(file.Version).Append('\n');
        sb.Append("cards:\n");

        foreach (var card in file.Cards)
        {
            sb.Append("  - nameId: ").Append(card.NameId).Append('\n');
            sb.Append("    nameEn: ").Append(Quote(card.NameEn)).Append('\n');
            AppendBlock(sb, "template", card.Template);
            sb.Append("    textRu: ").Append(Quote(card.TextRu ?? string.Empty)).Append('\n');
        }

        File.WriteAllText(path, sb.ToString(), new UTF8Encoding(encoderShouldEmitUTF8Identifier: false));
    }

    public static TranslationFile Read(string path)
    {
        var deserializer = new DeserializerBuilder()
            .WithNamingConvention(CamelCaseNamingConvention.Instance)
            .IgnoreUnmatchedProperties()
            .Build();

        return deserializer.Deserialize<TranslationFile>(File.ReadAllText(path)) ?? new TranslationFile();
    }

    private static void AppendBlock(StringBuilder sb, string key, string? value)
    {
        if (string.IsNullOrEmpty(value))
        {
            sb.Append("    ").Append(key).Append(": \"\"\n");
            return;
        }

        sb.Append("    ").Append(key).Append(": |-\n");
        foreach (var line in value.ReplaceLineEndings("\n").Split('\n'))
            sb.Append("      ").Append(line.TrimEnd()).Append('\n');
    }

    private static string Quote(string value) =>
        "\"" + value
            .Replace("\\", "\\\\")
            .Replace("\"", "\\\"")
            .Replace("\r", string.Empty)
            .Replace("\n", "\\n") + "\"";
}

public sealed record TranslationIssue(string NameId, string Code, string Message);

public sealed record TranslationReport(
    int Total,
    int Translated,
    IReadOnlyList<TranslationIssue> Issues)
{
    public bool IsComplete => Issues.Count == 0;
}

public static class TranslationService
{
    /// <summary>
    /// Собирает шаблоны из каталога, сохраняя уже введённые переводы.
    /// </summary>
    public static TranslationFile Build(CardCatalog catalog, TranslationFile? existing)
    {
        var previous = existing?.Cards.ToDictionary(c => c.NameId, StringComparer.Ordinal)
                       ?? new Dictionary<string, TranslationEntry>(StringComparer.Ordinal);

        var cards = catalog.Cards
            .OrderBy(c => c.NameId, StringComparer.Ordinal)
            .Select(card =>
            {
                previous.TryGetValue(card.NameId, out var old);
                return new TranslationEntry
                {
                    NameId = card.NameId,
                    NameEn = card.NameEn,
                    Template = CardText.CardTextTokenizer.ToTemplate(card.TextEn),
                    TextRu = old?.TextRu ?? string.Empty,
                };
            })
            .ToList();

        return new TranslationFile { Version = 1, Cards = cards };
    }

    public static TranslationReport Check(TranslationFile file, CardText.KeywordCatalog? keywords = null)
    {
        var issues = new List<TranslationIssue>();
        var translated = 0;
        var unknown = new HashSet<string>(StringComparer.Ordinal);

        foreach (var card in file.Cards)
        {
            var hasText = string.IsNullOrWhiteSpace(card.Template) || !string.IsNullOrWhiteSpace(card.TextRu);

            if (hasText)
                translated++;
            else
                issues.Add(new TranslationIssue(card.NameId, "text.missing", "Не заполнено textRu."));

            var source = CardText.CardTextTokenizer.ExtractTokens(card.Template);
            var target = CardText.CardTextTokenizer.ExtractTokens(card.TextRu);

            if (!string.IsNullOrWhiteSpace(card.TextRu))
            {
                foreach (var (token, count) in source)
                {
                    var actual = target.GetValueOrDefault(token);
                    if (actual != count)
                    {
                        issues.Add(new TranslationIssue(
                            card.NameId,
                            "token.mismatch",
                            $"Токен {{{token}}}: в шаблоне {count}, в переводе {actual}."));
                    }
                }

                foreach (var (token, count) in target)
                {
                    if (source.ContainsKey(token))
                        continue;

                    issues.Add(new TranslationIssue(
                        card.NameId,
                        "token.extra",
                        $"В переводе лишний токен {{{token}}} ({count})."));
                }
            }

            if (keywords is not null)
            {
                var tokens = CardText.CardTextTokenizer.ExtractTokens(card.Template).Keys
                    .Concat(CardText.CardTextTokenizer.ExtractTokens(card.TextRu).Keys);

                foreach (var token in tokens)
                {
                    var parts = token.Split(':', 2);
                    var name = parts[0];
                    var value = parts.Length > 1 ? parts[1] : null;

                    if (!keywords.ContainsToken(name, value) && unknown.Add(token))
                    {
                        issues.Add(new TranslationIssue(
                            card.NameId,
                            "token.unknown",
                            $"Токен {{{token}}} отсутствует в content/keywords.yaml."));
                    }
                }
            }
        }

        return new TranslationReport(file.Cards.Count, translated, issues);
    }
}