using AdventOfCode.Core.Shared;

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 InputReader() => SetInputByChallange();

        public void SetInputByChallange()
        {
            SetInputByChallange(DateTime.Now.Day, DateTime.Now.Year);
        }

        public void SetInputByChallange(int day)
        {
            SetInputByChallange(day, DateTime.Now.Year);
        }

        public void SetInputByChallange(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[]> ReadAsArraytString()
        {
            return File.ReadAllLinesAsync(InputFilePath);
        }

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

            return result;
        }
    }
}