using AdventOfCode.Core.Shared;
using AdventOfCode.Core.Shared.Grid;

namespace AdventOfCode.Core
{
    public class InputReader
    {
        private readonly string InputFileTemplate = "../../../../AdventOfCode.Solutions/{1}/Day {0:00}/day-{0:00}-input.txt";
        private readonly string DebugInputFileTemplate = "../../../../AdventOfCode.Solutions/day-00-input.txt";
        public bool IsDebug = false;

        private int Day { get; set; }
        private int Year { get; set; }
        private string InputFilePath => IsDebug ? DebugInputFileTemplate : string.Format(InputFileTemplate, Day, Year);

        public void SetInput(IChallange challange)
        {
            Day = challange.Day;
            Year = challange.Year;
        }

        public void SetInput(int day, int year)
        {
            Day = day;
            Year = year;
        }

        public async Task<string> ReadAsString() => await File.ReadAllTextAsync(InputFilePath);

        public async IAsyncEnumerable<string> ReadAsStringLine()
        {
            using StreamReader reader = new(InputFilePath);
            while (!reader.EndOfStream)
            {
                yield return (await reader.ReadLineAsync()) ?? string.Empty;
            }
        }

        public Task<string[]> ReadAsArrayString()
        {
            return File.ReadAllLinesAsync(InputFilePath);
        }

        public async Task<string[]> ReadAsVerticalArrayString()
        {
            var data = await File.ReadAllLinesAsync(InputFilePath);
            List<string> result = [];
            for (int index = 0; index < data[0].Length; index++)
            {
                result.Add(string.Concat(data.Select(l => l.Skip(index).First())));
            }

            return [.. result];
        }   

        public async IAsyncEnumerable<T> ReadAsStringLine<T>(T emptyLineIndicator)
        {
            using StreamReader reader = new(InputFilePath);
            while (!reader.EndOfStream)
            {
                string line = (await reader.ReadLineAsync()) ?? string.Empty;
                if (string.IsNullOrWhiteSpace(line))
                    yield return emptyLineIndicator;
                else
                    yield return (T)Convert.ChangeType(line, typeof(T));
            }
        }

        public async IAsyncEnumerable<long[]> ReadLineAsLongArray(string seperator)
        {
            using StreamReader reader = new(InputFilePath);
            while (!reader.EndOfStream)
            {
                string line = (await reader.ReadLineAsync()) ?? string.Empty;
                if (string.IsNullOrWhiteSpace(line))
                    yield return [];
                else
                    yield return line.Split(seperator).Select(long.Parse).ToArray();
            }
        }

        public async Task<Grid<T>> ReadToGrid<T>() where T : Point, new()
        {
            Grid<T> result = new();
            int row = 0;
            await foreach(string line in ReadAsStringLine())
            {
                // create the nodes from the lines
                result.DataGrid.AddRange(line.Select((c, i) => new T { X = i, Y = row, Value = c }));
                row++;
            }

            return result;
        }

        public async IAsyncEnumerable<Grid<T>> ReadToGrids<T>() where T : Node, new()
        {
            Grid<T> result = new();
            int row = 0;
            string[] data = await ReadAsArrayString();
            foreach (string line in data)
            {
                if (string.IsNullOrWhiteSpace(line))
                {
                    yield return result;
                    result = new Grid<T>();
                    row = 0;
                    continue;
                }
                // create the nodes from the lines
                result.DataGrid.AddRange(line.Select((c, i) => new T { X = i, Y = row, Value = c }));
                row++;
            }
            yield return result;
            yield break;
        }
    }
}