// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

#nullable disable

using System;
using System.Diagnostics;
using System.Globalization;
using System.Reflection;
using Microsoft.CodeAnalysis.PooledObjects;
using static Microsoft.CodeAnalysis.Scripting.Hosting.ObjectFormatterHelpers;

namespace Microsoft.CodeAnalysis.Scripting.Hosting
{
    /// <summary>
    /// Object pretty printer.
    /// </summary>
    internal abstract partial class CommonObjectFormatter : ObjectFormatter
    {
        public override string FormatObject(object obj, PrintOptions options)
        {
            if (options == null)
            {
                // We could easily recover by using default options, but it makes
                // more sense for the host to choose the defaults so we'll require
                // that options be passed.
                throw new ArgumentNullException(nameof(options));
            }

            var visitor = new Visitor(this, GetInternalBuilderOptions(options), GetPrimitiveOptions(options), GetTypeNameOptions(options), options.MemberDisplayFormat);
            return visitor.FormatObject(obj);
        }

        protected virtual MemberFilter Filter { get; } = new CommonMemberFilter();

        protected abstract CommonTypeNameFormatter TypeNameFormatter { get; }
        protected abstract CommonPrimitiveFormatter PrimitiveFormatter { get; }

        protected virtual BuilderOptions GetInternalBuilderOptions(PrintOptions printOptions)
            => new BuilderOptions(
                indentation: "  ",
                newLine: Environment.NewLine,
                ellipsis: printOptions.Ellipsis,
                maximumLineLength: int.MaxValue,
                maximumOutputLength: printOptions.MaximumOutputLength);

        protected virtual CommonPrimitiveFormatterOptions GetPrimitiveOptions(PrintOptions printOptions)
            => new CommonPrimitiveFormatterOptions(
                numberRadix: printOptions.NumberRadix,
                includeCodePoints: false,
                quoteStringsAndCharacters: true,
                escapeNonPrintableCharacters: printOptions.EscapeNonPrintableCharacters,
                cultureInfo: CultureInfo.CurrentUICulture);

        protected virtual CommonTypeNameFormatterOptions GetTypeNameOptions(PrintOptions printOptions)
            => new CommonTypeNameFormatterOptions(
                arrayBoundRadix: printOptions.NumberRadix,
                showNamespaces: false);

        public override string FormatException(Exception e)
        {
            if (e == null)
            {
                throw new ArgumentNullException(nameof(e));
            }

            var pooled = PooledStringBuilder.GetInstance();
            var builder = pooled.Builder;

            builder.Append(e.GetType());
            builder.Append(": ");
            builder.Append(e.Message);
            builder.Append(Environment.NewLine);

            var trace = new StackTrace(e, fNeedFileInfo: true);
            foreach (var frame in trace.GetFrames())
            {
                if (!Filter.Include(frame))
                {
                    continue;
                }

                var method = frame.GetMethod();
                var methodDisplay = FormatMethodSignature(method);

                if (methodDisplay == null)
                {
                    continue;
                }

                builder.Append("  + ");
                builder.Append(methodDisplay);

                var fileName = frame.GetFileName();
                if (fileName != null)
                {
                    builder.Append(string.Format(CultureInfo.CurrentUICulture, ScriptingResources.AtFileLine, fileName, frame.GetFileLineNumber()));
                }

                builder.AppendLine();
            }

            return pooled.ToStringAndFree();
        }

        /// <summary>
        /// Returns a method signature display string. Used to display stack frames.
        /// </summary>
        /// <returns>Null if the method is a compiler generated method that shouldn't be displayed to the user.</returns>
        protected internal virtual string FormatMethodSignature(MethodBase method)
        {
            var pooled = PooledStringBuilder.GetInstance();
            var builder = pooled.Builder;

            var declaringType = method.DeclaringType;
            var options = new CommonTypeNameFormatterOptions(arrayBoundRadix: NumberRadixDecimal, showNamespaces: true);

            builder.Append(TypeNameFormatter.FormatTypeName(declaringType, options));
            builder.Append('.');
            builder.Append(method.Name);
            if (method.IsGenericMethod)
            {
                builder.Append(TypeNameFormatter.FormatTypeArguments(method.GetGenericArguments(), options));
            }

            builder.Append('(');

            bool first = true;
            foreach (var parameter in method.GetParameters())
            {
                if (first)
                {
                    first = false;
                }
                else
                {
                    builder.Append(", ");
                }

                if (parameter.ParameterType.IsByRef)
                {
                    builder.Append(FormatRefKind(parameter));
                    builder.Append(' ');
                    builder.Append(TypeNameFormatter.FormatTypeName(parameter.ParameterType.GetElementType(), options));
                }
                else
                {
                    builder.Append(TypeNameFormatter.FormatTypeName(parameter.ParameterType, options));
                }
            }

            builder.Append(')');

            return pooled.ToStringAndFree();
        }

        protected abstract string FormatRefKind(ParameterInfo parameter);
    }
}