using System;
using System.IO;
using System.Collections.Generic;
using System.Collections;
using System.Net.Mail;

namespace Day03CSharp
{
    internal class Program
    {

        static int GetValue(char c)
        {
            if (c >= 'a' && c <= 'z')
            {
                return (int)c - (int)'a' + 1;
            }
            else if (c >= 'A' && c <= 'Z')
            {
                return (int)c - (int)'A' + 27;
            }
            else
            {
                throw new InvalidDataException("Compartment contains character that isnt an ascii english letter");
            }
        }

        class Rucksack
        {
            public Dictionary<char, int> left = new Dictionary<char, int>();
            public Dictionary<char, int> right = new Dictionary<char, int>();

            public Rucksack() 
            { 

            }

            public Rucksack(string line)
            {
                if (line.Length % 2 != 0)
                {
                    throw new ArgumentException("string used to load rucksack isnt even in length");
                }

                var fillFunc = delegate (char c, Dictionary<char, int> dict)
                {
                    if (!((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')))
                    {
                        throw new ArgumentOutOfRangeException("Input isn't a<->z or A<->Z");
                    }

                    if (!dict.ContainsKey(c))
                    {
                        dict.Add(c, 0);
                    }

                    dict[c]++;
                };

                // fill the left compartment
                for (int i = 0; i < line.Length / 2; i++)
                {
                    fillFunc(line[i], left);
                }

                // fill the right
                for (int i = line.Length / 2; i < line.Length; i++)
                {
                    fillFunc(line[i], right);
                }
            }

            public char Duplicate
            {
                get
                {
                    foreach (var c in left.Keys)
                    {
                        if (right.ContainsKey(c))
                        {
                            return c;
                        }
                    }

                    throw new InvalidDataException("Left and right compartment are missing a duplicate character");
                }
            }

            public int DuplicateValue
            {
                get
                {
                    return GetValue(Duplicate);
                }
            }

            public bool Contains(char c)
            {
                return left.ContainsKey(c) || right.ContainsKey(c);
            }

            public List<char> Keys
            {
                get
                {
                    var list = new List<char>();
                    foreach (var c in left.Keys)
                    {
                        list.Add(c);
                    }

                    foreach(var c in right.Keys)
                    {
                        if (!list.Contains(c))
                        {
                            list.Add(c);
                        }
                    }

                    list.Sort();

                    return list;
                }
            }
        }

        static List<Rucksack> GetRucksacks(string fileName)
        {
            List<Rucksack> list = new List<Rucksack>();

            using (StreamReader reader = File.OpenText(fileName))
            {
                while (!reader.EndOfStream)
                {
                    string line = reader.ReadLine();
                    Rucksack r = new Rucksack(line);
                    list.Add(r);
                }
            }

            return list;
        }

        /****************************************
        // part 01
        */

        static void Part01(string fileName)
        {
            var list = GetRucksacks(fileName);

            // We have all the rucksacks, add up the stuff
            int sum = 0;
            foreach (var r in list)
            {
                sum += r.DuplicateValue;
            }

            Console.WriteLine("Priority Sum: " + sum);
        }

        /****************************************
        // Part 02
        */

        class Group
        {
            public Group() { }
            public Rucksack[] rucksacks = new Rucksack[3];

            public char Duplicate
            {
                get
                {
                    var list = rucksacks[0].Keys;

                    foreach (var key in list)
                    {
                        if (rucksacks[1].Contains(key) && rucksacks[2].Contains(key))
                        {
                            return key;
                        }
                    }

                    throw new InvalidDataException();
                }
            }

            public int DuplicateValue
            {
                get 
                {
                    return GetValue(Duplicate);
                }
            }
        }

        static List<Group> GetGroups(string fileName)
        {
            var list = GetRucksacks(fileName);

            if (list.Count % 3 != 0)
            {
                throw new InvalidDataException("List of rucksacks isn't divisible by 3, cant create groups");
            }

            List<Group> groups = new List<Group>();

            for (int i = 0; i < list.Count; i+=3)
            {
                var group = new Group();

                group.rucksacks[0] = list[i+0];
                group.rucksacks[1] = list[i+1];
                group.rucksacks[2] = list[i+2];

                groups.Add(group);
            }

            return groups;
        }

        static void Part02(string fileName)
        {
            var groups = GetGroups(fileName);
            int sum = 0;
            foreach (var group in groups)
            {
                sum += group.DuplicateValue;
            }

            Console.WriteLine("Group Priority: " + sum);
        }

        static void Main(string[] args)
        {
            //const string fileName = @"example-input01.txt";
            const string fileName = @"puzzle-input01.txt";
            Part01(fileName);
            Part02(fileName);
        }
    }
}