using System;
using System.Collections.Generic;
using System.Text.RegularExpressions;

namespace SourceGit.Commands {
    /// <summary>
    ///     逐行追溯
    /// </summary>
    public class Blame : Command {
        private static readonly Regex REG_FORMAT = new Regex(@"^\^?([0-9a-f]+)\s+.*\((.*)\s+(\d+)\s+[\-\+]?\d+\s+\d+\) (.*)");
        private Data data = new Data();

        public class Data {
            public List<Models.BlameLine> Lines = new List<Models.BlameLine>();
            public bool IsBinary = false;
        }

        public Blame(string repo, string file, string revision) {
            Cwd = repo;
            Args = $"blame -t {revision} -- \"{file}\"";
        }

        public Data Result() {
            Exec();
            return data;
        }

        public override void OnReadline(string line) {
            if (data.IsBinary) return;
            if (string.IsNullOrEmpty(line)) return;

            if (line.IndexOf('\0') >= 0) {
                data.IsBinary = true;
                data.Lines.Clear();
                return;
            }

            var match = REG_FORMAT.Match(line);
            if (!match.Success) return;

            var commit = match.Groups[1].Value;
            var author = match.Groups[2].Value;
            var timestamp = int.Parse(match.Groups[3].Value);
            var content = match.Groups[4].Value;
            var when = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc).AddSeconds(timestamp).ToLocalTime().ToString("yyyy-MM-dd HH:mm:ss");

            var blameLine = new Models.BlameLine() {
                LineNumber = $"{data.Lines.Count + 1}",
                CommitSHA = commit,
                Author = author,
                Time = when,
                Content = content,
            };

            data.Lines.Add(blameLine);
        }
    }
}