using System.Collections.Generic;
using System.IO;
using System.Linq;
using Microsoft.CodeAnalysis.CSharp.Syntax;

namespace wvdet.CodeChecker
{
    /// <summary>
    /// Struct [结构体] 命名规范
    /// 使用 Pascal Case。
    /// 使用名词或者名词性词组命名接口。
    /// 不要轻易使用缩写。
    /// 在struct 名称前加上字母S来表示type是在struct。(如：SData)
    /// 不使用下划线。
    /// 文件名应和类名相同。
    /// </summary>
    public class CheckStruct : ICheckable
    {
        public List<Detail> Check(string filepath, CompilationUnitSyntax root)
        {
            var results = new List<Detail>();

            var interfaceDecs = root.DescendantNodes().OfType<StructDeclarationSyntax>().ToList();
            foreach (var dec in interfaceDecs)
            {
                var identifier = dec.Identifier.ValueText;
                var lineNumber = dec.GetLocation().GetLineSpan().StartLinePosition.Line;

                if (CheckerUtils.IsChineseIdentifier(identifier, lineNumber, out var ret))
                    results.Add(ret);

                if (!char.IsLower(identifier[0]))
                {
                    results.Add(new Detail
                    {
                        level = Level.Error,
                        line = lineNumber,
                        codeSnippet = identifier.Trim(),
                        suggestion = CheckerUtils.ConvertPascalCase("S" + identifier),
                        guideline = "结构体类型名必须使用PascalCase",
                    });
                }

                else if (identifier[0] != 'S')
                {
                    results.Add(new Detail
                    {
                        level = Level.Warning,
                        line = lineNumber,
                        codeSnippet = identifier.Trim(),
                        suggestion = CheckerUtils.ConvertPascalCase("S" + identifier),
                        guideline = "在struct名称前加上字母S来表示type是struct。(如：SData)",
                    });
                }

                else if (identifier[0] == '_')
                {
                    results.Add(new Detail
                    {
                        level = Level.Error,
                        line = lineNumber,
                        codeSnippet = identifier.Trim(),
                        suggestion = CheckerUtils.ConvertPascalCase("S" + identifier.Substring(1)),
                        guideline = "结构体名禁用以下划线开始",
                    });
                }
            }

            var filename = Path.GetFileNameWithoutExtension(filepath);
            if (interfaceDecs.Count > 0 && interfaceDecs.All(x => x.Identifier.ValueText != filename))
            {
                results.Add(new Detail
                {
                    level = Level.Warning,
                    guideline = "文件名应和类名相同",
                });
            }

            return results;
        }
    }
}