using System.Text.RegularExpressions;

using PluralKit.Core;

namespace PluralKit.Bot;

public class Admin
{
    private readonly BotConfig _botConfig;
    private readonly ModelRepository _repo;

    public Admin(BotConfig botConfig, ModelRepository repo)
    {
        _botConfig = botConfig;
        _repo = repo;
    }

    public async Task UpdateSystemId(Context ctx)
    {
        ctx.AssertBotAdmin();

        var target = await ctx.MatchSystem();
        if (target == null)
            throw new PKError("Unknown system.");

        var newHid = ctx.PopArgument();
        if (!Regex.IsMatch(newHid, "^[a-z]{5}$"))
            throw new PKError($"Invalid new system ID `{newHid}`.");

        var existingSystem = await _repo.GetSystemByHid(newHid);
        if (existingSystem != null)
            throw new PKError($"Another system already exists with ID `{newHid}`.");

        if (!await ctx.PromptYesNo($"Change system ID of `{target.Hid}` to `{newHid}`?", "Change"))
            throw new PKError("ID change cancelled.");

        await _repo.UpdateSystem(target.Id, new SystemPatch { Hid = newHid });
        await ctx.Reply($"{Emojis.Success} System ID updated (`{target.Hid}` -> `{newHid}`).");
    }

    public async Task UpdateMemberId(Context ctx)
    {
        ctx.AssertBotAdmin();

        var target = await ctx.MatchMember();
        if (target == null)
            throw new PKError("Unknown member.");

        var newHid = ctx.PopArgument();
        if (!Regex.IsMatch(newHid, "^[a-z]{5}$"))
            throw new PKError($"Invalid new member ID `{newHid}`.");

        var existingMember = await _repo.GetMemberByHid(newHid);
        if (existingMember != null)
            throw new PKError($"Another member already exists with ID `{newHid}`.");

        if (!await ctx.PromptYesNo(
            $"Change member ID of **{target.NameFor(LookupContext.ByNonOwner)}** (`{target.Hid}`) to `{newHid}`?",
            "Change"
        ))
            throw new PKError("ID change cancelled.");

        await _repo.UpdateMember(target.Id, new MemberPatch { Hid = newHid });
        await ctx.Reply($"{Emojis.Success} Member ID updated (`{target.Hid}` -> `{newHid}`).");
    }

    public async Task UpdateGroupId(Context ctx)
    {
        ctx.AssertBotAdmin();

        var target = await ctx.MatchGroup();
        if (target == null)
            throw new PKError("Unknown group.");

        var newHid = ctx.PopArgument();
        if (!Regex.IsMatch(newHid, "^[a-z]{5}$"))
            throw new PKError($"Invalid new group ID `{newHid}`.");

        var existingGroup = await _repo.GetGroupByHid(newHid);
        if (existingGroup != null)
            throw new PKError($"Another group already exists with ID `{newHid}`.");

        if (!await ctx.PromptYesNo($"Change group ID of **{target.Name}** (`{target.Hid}`) to `{newHid}`?",
            "Change"
        ))
            throw new PKError("ID change cancelled.");

        await _repo.UpdateGroup(target.Id, new GroupPatch { Hid = newHid });
        await ctx.Reply($"{Emojis.Success} Group ID updated (`{target.Hid}` -> `{newHid}`).");
    }

    public async Task SystemMemberLimit(Context ctx)
    {
        ctx.AssertBotAdmin();

        var target = await ctx.MatchSystem();
        if (target == null)
            throw new PKError("Unknown system.");

        var currentLimit = target.MemberLimitOverride ?? Limits.MaxMemberCount;
        if (!ctx.HasNext())
        {
            await ctx.Reply($"Current member limit is **{currentLimit}** members.");
            return;
        }

        var newLimitStr = ctx.PopArgument();
        if (!int.TryParse(newLimitStr, out var newLimit))
            throw new PKError($"Couldn't parse `{newLimitStr}` as number.");

        if (!await ctx.PromptYesNo($"Update member limit from **{currentLimit}** to **{newLimit}**?", "Update"))
            throw new PKError("Member limit change cancelled.");

        await _repo.UpdateSystem(target.Id, new SystemPatch { MemberLimitOverride = newLimit });
        await ctx.Reply($"{Emojis.Success} Member limit updated.");
    }

    public async Task SystemGroupLimit(Context ctx)
    {
        ctx.AssertBotAdmin();

        var target = await ctx.MatchSystem();
        if (target == null)
            throw new PKError("Unknown system.");

        var currentLimit = target.GroupLimitOverride ?? Limits.MaxGroupCount;
        if (!ctx.HasNext())
        {
            await ctx.Reply($"Current group limit is **{currentLimit}** groups.");
            return;
        }

        var newLimitStr = ctx.PopArgument();
        if (!int.TryParse(newLimitStr, out var newLimit))
            throw new PKError($"Couldn't parse `{newLimitStr}` as number.");

        if (!await ctx.PromptYesNo($"Update group limit from **{currentLimit}** to **{newLimit}**?", "Update"))
            throw new PKError("Group limit change cancelled.");

        await _repo.UpdateSystem(target.Id, new SystemPatch { GroupLimitOverride = newLimit });
        await ctx.Reply($"{Emojis.Success} Group limit updated.");
    }
}