using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Text;
using CodeLiturgy.Augeas.Test;
using static CodeLiturgy.Augeas.AugeasExtern;
using static CodeLiturgy.Augeas.AugFlags;

namespace CodeLiturgy.Augeas
{
    /// <summary>
    ///  Augeas Core containing the settings of this instance.
    ///  We can have multiple augeas cores during the execution.
    /// </summary>
    public unsafe partial class Augeas
    {
        private readonly IntPtr _augeas;

        /// <summary>
        /// Augeas Core Destructor
        /// </summary>
        ~Augeas()
        {
            // Effectively free the pointer
            close_aug(_augeas);
        }
        
        /// <summary>
        /// Augeas Core constructor
        /// </summary>
        /// <param name="augSettings">Augeas core instance settings</param>
        public Augeas(AugSettings augSettings)
        {
            _augeas = init_aug(augSettings, NO_STDINC | NO_LOAD);
        }

        /// <summary>
        /// Prints a preview of the desired segment in <see cref="matchPath"/>
        /// </summary>
        /// <param name="matchPath">Augeas path to filter out the configuration</param>
        /// <param name="filePath">The actual configuration file path</param>
        public void PrintPreview(string matchPath)
        {
            print_preview(_augeas, matchPath);
        }

        /// <summary>
        /// Finalize the augeas instance.
        /// </summary>
        public void Close()
        {
            close_aug(_augeas);
        }

        /// <summary>
        /// Finalize the augeas instance.
        /// </summary>
        public void LoadFile(string configurationFilePath)
        {
            load_file(_augeas, configurationFilePath);
        }

        /// <summary>
        /// Prints the Aug Tree of a segment 
        /// </summary>
        /// <param name="matchPath"></param>
        /// <param name="filePath"></param>
        public void PrintAugTree(string matchPath)
        {
            print_tree(_augeas, matchPath);
        }
        

        /// <summary>
        /// Returns the tree given the augeas configuration path.
        /// </summary>
        /// <param name="matchPath">configuration path.</param>
        /// <returns>Dictionary with the Tree</returns>
        public Dictionary<string,string> GetTree(string matchPath)
        {
            var result =  new Dictionary<string, string>();
            var raw = get_tree(_augeas, matchPath);
            string sb = Marshal.PtrToStringAnsi((IntPtr)raw);
            if (sb == null) return result;
            free_str(raw);
            var lines = sb.Split(";ENDL;");
            foreach (var line in lines)
            {
                var pair = line.Split(";VAL;");
                if (pair.Length == 2)
                {
                    result.Add(pair[0].Remove(0, 3), pair[1]);
                }
            }

            return result;
        }
        
        
        
        public static void Benchmark(Action act, int iterations)
        {
            GC.Collect();
            act.Invoke(); // run once outside of loop to avoid initialization costs
            Stopwatch sw = Stopwatch.StartNew();
            for (int i = 0; i < iterations; i++)
            {
                act.Invoke();
            }
            sw.Stop();
            Console.WriteLine((sw.ElapsedMilliseconds / iterations).ToString());
        }
    }
}