using Microsoft.AspNetCore.Hosting;
using MiaoYu.Core.CodeGenerator.Abstractions;

namespace MiaoYu.Core.CodeGenerator.Core;

/// <summary>
/// 路径解析器
/// </summary>
[Component]
public class PathResolver : IScopedDependency
{
    private readonly IWebHostEnvironment _environment;

    public PathResolver(IWebHostEnvironment environment)
    {
        _environment = environment;
    }

    /// <summary>
    /// 解析路径模板
    /// </summary>
    /// <param name="template">路径模板（支持占位符）</param>
    /// <param name="config">数据源配置</param>
    /// <param name="tableName">表名</param>
    /// <returns>解析后的完整路径</returns>
    public string ResolvePath(string template, DataSourceConfig config, string tableName)
    {
        if (string.IsNullOrWhiteSpace(template))
            return string.Empty;

        var rootPath = _environment.ContentRootPath
            .Replace("\\" + _environment.ApplicationName, "");
        var webPath = Path.GetDirectoryName(Path.GetDirectoryName(_environment.ContentRootPath))
            .Replace("\\" + _environment.ApplicationName, "");
        var entityName = GetEntityName(tableName, config);
        var entityNamePlural = config.UsesPluralPath ? entityName + "s" : entityName;
        var tableNameLower = string.IsNullOrWhiteSpace(tableName) ? string.Empty : tableName.ToLower();

        return template
            .Replace("{RootPath}", rootPath)
            .Replace("{WebPath}", webPath)
            .Replace("{AppPath}", _environment.ContentRootPath)
            .Replace("{Namespace}", config.EntityNamespace)
            .Replace("{EntityName}", entityName)
            .Replace("{EntityNamePlural}", entityNamePlural)
            .Replace("{TableName}", tableName)
            .Replace("{TableNameLower}", tableNameLower);
    }

    /// <summary>
    /// 根据命名策略和配置获取实体名
    /// </summary>
    /// <param name="tableName">表名</param>
    /// <param name="config">数据源配置</param>
    /// <returns>实体名</returns>
    public string GetEntityName(string tableName, DataSourceConfig config)
    {
        var baseName = config.NamingStrategy == EntityNamingStrategy.ToPascalCase
            ? ConvertToPascalCase(tableName)
            : tableName;

        // 应用前缀（如果启用）
        if (config.EnableEntityPrefix && !string.IsNullOrWhiteSpace(config.EntityPrefix))
        {
            return config.EntityPrefix + baseName;
        }

        return baseName;
    }

    /// <summary>
    /// 将下划线命名转换为 PascalCase
    /// </summary>
    private static string ConvertToPascalCase(string input)
    {
        if (string.IsNullOrEmpty(input))
            return input;

        var words = input.Split(new[] { '_', '-' }, StringSplitOptions.RemoveEmptyEntries);
        var result = new System.Text.StringBuilder();

        foreach (var word in words)
        {
            if (word.Length > 0)
            {
                result.Append(char.ToUpper(word[0]));
                if (word.Length > 1)
                {
                    result.Append(word.Substring(1).ToLower());
                }
            }
        }

        return result.ToString();
    }
}