package modules

import (
	"crypto/rand"
	"crypto/sha512"
	"encoding/hex"
	"fmt"

	"github.com/bwmarrin/discordgo"

	"TerraOceanBot/discord/backend"
	"TerraOceanBot/discord/config"
	"TerraOceanBot/discord/message"
)

//adminID is my Discord user ID (chanbakjsd#7968).
const adminID = "218983355746746369"

func adminOnly(passOn CommandHandler) CommandHandler {
	return func(s *discordgo.Session, m *discordgo.MessageCreate, command []string) {
		if m.Author.ID != adminID {
			return
		}
		passOn(s, m, command)
	}
}

var sendAs = adminOnly(enforceArgumentCount(config.SendAsUsage, 3,
	//!sendas <channel ID> <message>
	func(s *discordgo.Session, m *discordgo.MessageCreate, command []string) {
		msg, err := s.ChannelMessageSend(command[1], command[2])
		if err != nil {
			message.AuditError(s, m.ChannelID, err)
			return
		}
		message.InitNewEmbed(config.SuccessTitle, config.SendAsSuccessfulDescription, config.SuccessColour).
			AddField(config.SendAsSuccessfulMessageID, msg.ID).
			Send(s, m.ChannelID)
	},
))

var editAs = adminOnly(enforceArgumentCount(config.EditAsUsage, 4,
	//!editas <channel ID> <message ID> <message>
	func(s *discordgo.Session, m *discordgo.MessageCreate, command []string) {
		_, err := s.ChannelMessageEdit(command[1], command[2], command[3])
		if err != nil {
			message.AuditError(s, m.ChannelID, err)
			return
		}
		message.InitNewEmbed(config.SuccessTitle, config.EditAsSuccessfulDescription, config.SuccessColour).
			Send(s, m.ChannelID)
	},
))

var viewTrustLevel = adminOnly(func(s *discordgo.Session, m *discordgo.MessageCreate, command []string) {
	if len(command) > 1 && command[1] != "unobf" {
		user, err := backend.GetMemberFromUserFriendlyName(s, command[1])
		if err != nil {
			message.InitNewEmbed(
				config.ErrorVTLTitle,
				config.ErrorVTLTargetNotFound,
				config.ErrorColour,
			).Send(s, m.ChannelID)
			return
		}
		value, err := backend.GetTrust(s, user.User.ID)
		if err != nil {
			message.AuditError(s, m.ChannelID, err)
			return
		}
		total, err := backend.GetTotalTrust(s)
		if err != nil {
			message.AuditError(s, m.ChannelID, err)
			return
		}
		message.NewEmbed().SetColour(config.VTLColour).
			SetTitle(fmt.Sprintf(config.VTLSingleUserTitle, command[1], command[1])).
			AddField(config.VTLSingleUserValue, formatFloat(value, 1)).
			AddField(config.VTLSingleUserServerTotal, formatFloat(total, 1)).
			AddField(config.VTLSingleUserPercentage, formatFloat(value/total*100, 2)).
			Send(s, m.ChannelID)
		return
	}

	total, err := backend.GetTotalTrust(s)
	if err != nil {
		message.AuditError(s, m.ChannelID, err)
		return
	}
	members, err := backend.GetAllMembers(s)
	if err != nil {
		message.AuditError(s, m.ChannelID, err)
		return
	}

	salt := make([]byte, 16)
	rand.Read(salt)

	//Generate message
	hash := sha512.New()
	hash.Write(salt)
	msg := message.NewEmbed().SetColour(config.VTLColour).SetTitle(config.VTLGlobalTitle)
	for _, v := range members {
		value, err := backend.GetTrust(s, v.User.ID)
		if err == backend.ErrNotMember {
			continue
		}
		if err != nil {
			message.AuditError(s, m.ChannelID, err)
			return
		}
		var username string
		if len(command) > 1 {
			username = v.User.Username + "#" + v.User.Discriminator
		} else {
			toSalt := []byte(v.User.Username + "#" + v.User.Discriminator)
			username = hex.EncodeToString(hash.Sum(toSalt))[:64]
			if username == "" {
				username = "<cannot calculate hash>"
			}
		}
		msg.AddInlineField(
			username,
			fmt.Sprintf(config.VTLGlobalFieldFormat, value, total, value/total*100),
		)
	}
	_, err = msg.Send(s, m.ChannelID)
	if err != nil {
		message.AuditError(s, m.ChannelID, err)
		return
	}
})

var batchGiveRole = adminOnly(enforceDM(enforceArgumentCount(
	config.BatchRoleUsage, 2,
	func(s *discordgo.Session, m *discordgo.MessageCreate, command []string) {
		members, err := backend.GetAllMembers(s)
		if err != nil {
			message.AuditError(s, m.ChannelID, err)
			return
		}
		for _, member := range members {
			err := s.GuildMemberRoleAdd(
				config.GuildID,
				member.User.ID,
				command[1],
			)
			if err != nil {
				message.AuditError(s, m.ChannelID, err)
				return
			}
		}
		message.InitNewEmbed(config.SuccessTitle, config.BatchRoleSuccessMessage, config.SuccessColour).
			Send(s, m.ChannelID)
	},
)))