using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using System.Text;

namespace Luneraria.Core.Tests
{
    /// <summary>
    /// JSON protocol of a suite run, identical for the .NET harness and the Unity Test Runner
    /// (docs/port/logs/u1/core-tests.json, docs/port/logs/u1_5/*.json). The target file comes from
    /// the environment variable LUNE_TEST_REPORT; without it nothing is written.
    /// </summary>
    public sealed class SuiteReport
    {
        readonly StringBuilder _suites = new StringBuilder();
        int _count;

        public int Failures { get; private set; }

        public static string TargetPath { get { return Environment.GetEnvironmentVariable("LUNE_TEST_REPORT"); } }

        public void Add(CheckSuite suite, double seconds)
        {
            Failures += suite.Failures.Count;
            _suites.Append(_count == 0 ? "" : ",\n");
            _count++;
            _suites.AppendFormat(CultureInfo.InvariantCulture, "    {{\"suite\": \"{0}\", \"checks\": {1}, \"failures\": {2}, \"seconds\": {3:0.00}, \"failed\": [{4}], \"notes\": [{5}]}}",
                suite.Name, suite.Checks, suite.Failures.Count, seconds, Join(suite.Failures), Join(suite.Notes));
        }

        public string ToJson(string runtime, string label)
        {
            var text = new StringBuilder("{\n  \"suites\": [\n");
            text.Append(_suites);
            text.Append("\n  ],\n");
            text.Append("  \"runtime\": \"" + Escape(runtime) + "\",\n");
            text.Append("  \"label\": \"" + Escape(label) + "\",\n");
            text.Append("  \"os\": \"" + Escape(System.Runtime.InteropServices.RuntimeInformation.OSDescription + " " + System.Runtime.InteropServices.RuntimeInformation.ProcessArchitecture) + "\"\n}\n");
            return text.ToString();
        }

        public void WriteTo(string path, string runtime, string label)
        {
            string directory = Path.GetDirectoryName(Path.GetFullPath(path));
            if (!string.IsNullOrEmpty(directory))
                Directory.CreateDirectory(directory);
            File.WriteAllText(path, ToJson(runtime, label));
        }

        static string Join(List<string> values)
        {
            var parts = new List<string>();
            foreach (string value in values)
                parts.Add("\"" + Escape(value) + "\"");
            return string.Join(", ", parts);
        }

        static string Escape(string value)
        {
            return value.Replace("\\", "\\\\").Replace("\"", "\\\"").Replace("\n", "\\n");
        }
    }
}