using AdventOfCode.Core;

namespace AdventOfCode.Solutions._2023
{
    

    public class Day05(InputReader reader) : IChallange
    {
        private readonly InputReader _inputReader = reader;

        public const string SeedSoil = "seed-to-soil map:";
        public const string SoilFertilizer = "soil-to-fertilizer map:";
        public const string FertilizerWater = "fertilizer-to-water map:";
        public const string WaterLight = "water-to-light map:";
        public const string LightTemperature = "light-to-temperature map:";
        public const string TemperatureHumidity = "temperature-to-humidity map:";
        public const string HumidityLocation = "humidity-to-location map:";

        public async Task<string> GetSolutionPart1()
        {
            List<string> data = new(await _inputReader.ReadAsArrayString());

            SeedLocationMapper[] seeds = data[0].Split(' ').Skip(1).Select(s => new SeedLocationMapper { Seed = long.Parse(s) }).ToArray();

            // creating maps
            int stringSeperator = data.IndexOf(SeedSoil) + 1;
            List<InOutMapper> soil = MapData(data, stringSeperator, data.IndexOf(string.Empty, stringSeperator));

            stringSeperator = data.IndexOf(SoilFertilizer) + 1;
            List<InOutMapper> fertilizer = MapData(data, stringSeperator, data.IndexOf(string.Empty, stringSeperator));

            stringSeperator = data.IndexOf(FertilizerWater) + 1;
            List<InOutMapper> water = MapData(data, stringSeperator, data.IndexOf(string.Empty, stringSeperator));

            stringSeperator = data.IndexOf(WaterLight) + 1;
            List<InOutMapper> light = MapData(data, stringSeperator, data.IndexOf(string.Empty, stringSeperator));

            stringSeperator = data.IndexOf(LightTemperature) + 1;
            List<InOutMapper> temperature = MapData(data, stringSeperator, data.IndexOf(string.Empty, stringSeperator));

            stringSeperator = data.IndexOf(TemperatureHumidity) + 1;
            List<InOutMapper> humidity = MapData(data, stringSeperator, data.IndexOf(string.Empty, stringSeperator));

            stringSeperator = data.IndexOf(HumidityLocation) + 1;
            List<InOutMapper> location = MapData(data, stringSeperator, data.Count);

            foreach (SeedLocationMapper seed in seeds)
            {
                seed.Soil = GetTargetLocation(soil, seed.Seed);
                seed.Fertilizer = GetTargetLocation(fertilizer, seed.Soil);
                seed.Water = GetTargetLocation(water, seed.Fertilizer);
                seed.Light = GetTargetLocation(light, seed.Water);
                seed.Temperature = GetTargetLocation(temperature, seed.Light);
                seed.Humidity = GetTargetLocation(humidity, seed.Temperature);
                seed.Location = GetTargetLocation(location, seed.Humidity);
            }

            return seeds.Min(seed => seed.Location).ToString();
        }

        public async Task<string> GetSolutionPart2()
        {
            List<string> data = new(await _inputReader.ReadAsArrayString());

            int stringSeperator = data.IndexOf(SeedSoil) + 1;
            List<InOutMapper> soil = MapData(data, stringSeperator, data.IndexOf(string.Empty, stringSeperator));
            stringSeperator = data.IndexOf(SoilFertilizer) + 1;
            List<InOutMapper> fertilizer = MapData(data, stringSeperator, data.IndexOf(string.Empty, stringSeperator));
            stringSeperator = data.IndexOf(FertilizerWater) + 1;
            List<InOutMapper> water = MapData(data, stringSeperator, data.IndexOf(string.Empty, stringSeperator));
            stringSeperator = data.IndexOf(WaterLight) + 1;
            List<InOutMapper> light = MapData(data, stringSeperator, data.IndexOf(string.Empty, stringSeperator));
            stringSeperator = data.IndexOf(LightTemperature) + 1;
            List<InOutMapper> temperature = MapData(data, stringSeperator, data.IndexOf(string.Empty, stringSeperator));
            stringSeperator = data.IndexOf(TemperatureHumidity) + 1;
            List<InOutMapper> humidity = MapData(data, stringSeperator, data.IndexOf(string.Empty, stringSeperator));
            stringSeperator = data.IndexOf(HumidityLocation) + 1;
            List<InOutMapper> location = MapData(data, stringSeperator, data.Count);

            long[] seedData = data[0].Split(' ').Skip(1).Select(long.Parse).ToArray();
            long lowestLocation = long.MaxValue;

            List<long> proccessed = [];

            for (int seedDataIndex = 0; seedDataIndex < seedData.Length; seedDataIndex += 2)
            {
                for (long seedLocaton = seedData[seedDataIndex]; seedLocaton < seedData[seedDataIndex] + seedData[seedDataIndex + 1]; seedLocaton++)
                {
                    if (proccessed.Contains(seedLocaton))
                        continue;

                    long soilLocation = GetTargetLocation(soil, seedLocaton);
                    long fertilizerLocation = GetTargetLocation(fertilizer, soilLocation);
                    long waterLocation = GetTargetLocation(water, fertilizerLocation);
                    long lightLocation = GetTargetLocation(light, waterLocation);
                    long temperatureLocation = GetTargetLocation(temperature, lightLocation);
                    long humidityLocation = GetTargetLocation(humidity, temperatureLocation);
                    long locationLocation = GetTargetLocation(location, humidityLocation);

                    if (locationLocation < lowestLocation)
                        lowestLocation = locationLocation;

                    proccessed.Add(seedLocaton);
                }
            }

            return lowestLocation.ToString();
        }

        private static List<InOutMapper> MapData(List<string> data, int startIndex, int endIndex)
        {
            return data
                .Skip(startIndex)
                .Take(endIndex - startIndex)
                .Select(line => line
                    .Split(' ')
                    .Select(long.Parse)
                    .ToArray())
                .Select(values => 
                    new InOutMapper {  
                        DestinationStart = values[0],
                        SourceStart = values[1],
                        Range = values[2]
                    })
                .ToList();
        }

        private static long GetTargetLocation(List<InOutMapper> mapping, long location)
        {
            InOutMapper? mapper = mapping.FirstOrDefault(mapping => mapping.Intersect(location));
            return mapper != null ? location + mapper.Delta : location;
        }

        private class SeedLocationMapper
        {
            public long Seed { get; set; }

            public long Soil { get; set; }

            public long Fertilizer { get; set; }

            public long Water { get; set; }

            public long Light { get; set; }

            public long Temperature { get; set; }

            public long Humidity { get; set; }

            public long Location { get; set; }
        }

        private class InOutMapper
        {
            public long SourceStart { get; set; }

            public long DestinationStart { get; set; }

            public long Range { get; set; }

            public long Delta => DestinationStart - SourceStart;

            public bool Intersect (long value) => value >= SourceStart && value < SourceStart + Range;
        }
    }
}