namespace Service.AI;

/// <summary>
/// 分类图标生成提示词提供器实现
/// </summary>
public class ClassificationIconPromptProvider : IClassificationIconPromptProvider
{
    private readonly ILogger<ClassificationIconPromptProvider> _logger;
    private readonly IconPromptSettings _config;
    private readonly Random _random = new();

    public ClassificationIconPromptProvider(
        ILogger<ClassificationIconPromptProvider> logger,
        IOptions<IconPromptSettings> config)
    {
        _logger = logger;
        _config = config.Value;
    }

    public string GetPrompt(string categoryName, TransactionType categoryType)
    {
        var typeText = GetCategoryTypeText(categoryType);
        var useNewPrompt = ShouldUseNewPrompt();

        var template = useNewPrompt
            ? _config.DefaultPromptTemplate
            : _config.OldDefaultPromptTemplate;

        string prompt;
        if (useNewPrompt)
        {
            prompt = PromptTemplateEngine.ReplaceForIconGeneration(
                template,
                categoryName,
                typeText,
                _config.ColorScheme,
                _config.StyleStrength);
        }
        else
        {
            prompt = PromptTemplateEngine.ReplaceForIconGeneration(
                template,
                categoryName,
                typeText,
                _config.ColorScheme,
                0);
        }

        _logger.LogDebug("使用 {PromptType} 提示词生成图标，分类：{CategoryName}",
            useNewPrompt ? "新版" : "旧版",
            categoryName);

        return prompt;
    }

    public string GetSingleIconPrompt(string categoryName, TransactionType categoryType)
    {
        var typeText = GetCategoryTypeText(categoryType);
        var useNewPrompt = ShouldUseNewPrompt();

        var template = useNewPrompt
            ? _config.SingleIconPromptTemplate
            : _config.OldSingleIconPromptTemplate;

        string prompt;
        if (useNewPrompt)
        {
            prompt = PromptTemplateEngine.ReplaceForIconGeneration(
                template,
                categoryName,
                typeText,
                _config.ColorScheme,
                _config.StyleStrength);
        }
        else
        {
            prompt = PromptTemplateEngine.ReplaceForIconGeneration(
                template,
                categoryName,
                typeText,
                _config.ColorScheme,
                0);
        }

        _logger.LogDebug("使用 {PromptType} 提示词生成单个图标，分类：{CategoryName}",
            useNewPrompt ? "新版" : "旧版",
            categoryName);

        return prompt;
    }

    private bool ShouldUseNewPrompt()
    {
        if (!_config.EnableNewPrompt)
        {
            return false;
        }

        var randomValue = _random.NextDouble();
        return randomValue < _config.GrayScaleRatio;
    }

    private static string GetCategoryTypeText(TransactionType categoryType)
    {
        return categoryType switch
        {
            TransactionType.Expense => "支出",
            TransactionType.Income => "收入",
            TransactionType.None => "不计入收支",
            _ => "未知"
        };
    }
}