using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using ln.build.commands;
using ln.type;

namespace ln.build.pipeline
{

    public class StageCommandContainer
    {
        public StageCommandContainer Parent { get; }
        public string Name { get; }
        
        public string FullName => Parent?.FullName != null ? string.Format("{0} {1}", Parent.FullName, Name) : Name;

        Dictionary<string,Action<Stage,string[]>> commands = new Dictionary<string, Action<Stage,string[]>>();
        Dictionary<string,StageCommandContainer> children = new Dictionary<string, StageCommandContainer>();

        public StageCommandContainer(StageCommandContainer parent, string name)
        {
            Parent = parent;
            Name = name;
        }

        public void AddCommand(Action<Stage,string[]> commandAction, string commandPath) => AddCommand(commandAction, commandPath.Split());
        public void AddCommand(Action<Stage,string[]> commandAction, params string[] commandPath)
        {
            if (commandPath.Length == 0)
                throw new ArgumentException(nameof(commandPath));
            if (commandPath.Length > 1)
            {
                if (!children.TryGetValue(commandPath[0], out StageCommandContainer childContainer))
                {
                    childContainer = new StageCommandContainer(this, commandPath[0]);
                    children.Add(commandPath[0], childContainer);
                }
                childContainer.AddCommand(commandAction, commandPath.Slice(1));
            } else {
                commands.Add(commandPath[0], commandAction);
            }
        }

        public void Run(Stage stage, params string[] arguments)
        {
            if (commands.TryGetValue(arguments[0], out Action<Stage,string[]> commandAction))
                commandAction(stage, arguments.Slice(1));
            else if (children.TryGetValue(arguments[0], out StageCommandContainer childContainer))
                childContainer.Run(stage, arguments.Slice(1));
            else
                throw new ArgumentException(String.Format("command not found: {0}", arguments[0]));
        }
    }

}