using SharpChat.Packet;
using System.Linq;

namespace SharpChat.Commands {
    public class ChannelCreateCommand : IUserCommand {
        public bool IsMatch(UserCommandContext ctx) {
            return ctx.NameEquals("create");
        }

        public void Dispatch(UserCommandContext ctx) {
            if(!ctx.User.Permissions.HasFlag(UserPermissions.CreateChannel)) {
                ctx.Chat.SendTo(ctx.User, new CommandNotAllowedErrorPacket(ctx.Name));
                return;
            }

            string firstArg = ctx.Args.First();

            bool createChanHasHierarchy;
            if(!ctx.Args.Any() || (createChanHasHierarchy = firstArg.All(char.IsDigit) && ctx.Args.Length < 2)) {
                ctx.Chat.SendTo(ctx.User, new CommandFormatErrorPacket());
                return;
            }

            int createChanHierarchy = 0;
            if(createChanHasHierarchy)
                if(!int.TryParse(firstArg, out createChanHierarchy))
                    createChanHierarchy = 0;

            if(createChanHierarchy > ctx.User.Rank) {
                ctx.Chat.SendTo(ctx.User, new ChannelRankTooHighErrorPacket());
                return;
            }

            string createChanName = string.Join('_', ctx.Args.Skip(createChanHasHierarchy ? 1 : 0));

            if(!ChannelInfo.CheckName(createChanName)) {
                ctx.Chat.SendTo(ctx.User, new ChannelNameFormatErrorPacket());
                return;
            }

            if(ctx.Chat.Channels.Values.Any(c => c.NameEquals(createChanName))) {
                ctx.Chat.SendTo(ctx.User, new ChannelNameInUseErrorPacket(createChanName));
                return;
            }

            ChannelInfo createChan = new(
                createChanName,
                isTemporary: !ctx.User.Permissions.HasFlag(UserPermissions.SetChannelPermanent),
                rank: createChanHierarchy,
                ownerId: ctx.User.UserId
            );

            ctx.Chat.Channels.Add(createChan.Name, createChan);
            foreach(UserInfo ccu in ctx.Chat.Users.Values.Where(u => u.Rank >= ctx.Channel.Rank))
                ctx.Chat.SendTo(ccu, new ChannelCreatePacket(
                    ctx.Channel.Name,
                    ctx.Channel.HasPassword,
                    ctx.Channel.IsTemporary
                ));

            ctx.Chat.SwitchChannel(ctx.User, createChan, createChan.Password);
            ctx.Chat.SendTo(ctx.User, new ChannelCreateResponsePacket(createChan.Name));
        }
    }
}