package main

import (
	"database/sql"
	"fmt"
	"strings"
	"sync"

	sq "github.com/Masterminds/squirrel"
	"github.com/mattermost/mattermost/server/public/model"
	"github.com/mattermost/mattermost/server/public/plugin"
	pluginapi "github.com/mattermost/mattermost/server/public/pluginapi"
)

// Plugin implements the interface expected by the Mattermost server to communicate between the server and plugin processes.
type Plugin struct {
	plugin.MattermostPlugin

	// configurationLock synchronizes access to the configuration.
	configurationLock sync.RWMutex

	// configuration is the active plugin configuration. Consult getConfiguration and
	// setConfiguration for usage.
	configuration *configuration

	apiClient *pluginapi.Client

	db *sql.DB
}

// ServeHTTP demonstrates a plugin that handles HTTP requests by greeting the world.
// func (p *Plugin) ServeHTTP(c *plugin.Context, w http.ResponseWriter, r *http.Request) {
// 	fmt.Fprint(w, "Hello, world!")
// }

func (p *Plugin) Q() sq.StatementBuilderType {
	return sq.StatementBuilder.PlaceholderFormat(sq.Dollar).RunWith(p.db)
}

func (p *Plugin) OnActivate() error {
	p.apiClient = pluginapi.NewClient(p.API, p.Driver)

	db, dbErr := p.apiClient.Store.GetMasterDB()
	if dbErr != nil {
		return dbErr
	}
	p.db = db

	if err := p.API.UnregisterCommand("", "fawkes"); err != nil {
		return err
	}

	autocompleteData := model.NewAutocompleteData("fawkes", "[command]", "Gets information about the msteams current state")

	whitelistedCmd := model.NewAutocompleteData("count-whitelisted", "", "Counts the amount of whitelisted users in msteamssync_whitelisted_users")
	// adds the from arg?
	autocompleteData.AddCommand(whitelistedCmd)

	lastConnectAtCmd := model.NewAutocompleteData("count-lastconnectat", "", "Counts the amount of users with a lastconnectat value != 0 in msteamssync_whitelisted_users")
	autocompleteData.AddCommand(lastConnectAtCmd)

	lastDisconnectAtCmd := model.NewAutocompleteData("count-lastdisconnectat", "", "Counts the amount of users with a lastdisconnectat value != 0 in msteamssync_whitelisted_users")
	autocompleteData.AddCommand(lastDisconnectAtCmd)

	userInfoCmd := model.NewAutocompleteData("user-info", "[username|email]", "Returns information about the user state regarding msteams")
	autocompleteData.AddCommand(userInfoCmd)

	channelInfoCmd := model.NewAutocompleteData("channel-info", "[channelID]", "Returns information about the channel state regarding msteams")
	autocompleteData.AddCommand(channelInfoCmd)

	listInvitesCmd := model.NewAutocompleteData("list-invites", "", "List the current invites")
	autocompleteData.AddCommand(listInvitesCmd)

	removeInviteCmd := model.NewAutocompleteData("remove-invite", "[mmUserID]", "Deletes the invite for the user ID")
	autocompleteData.AddCommand(removeInviteCmd)

	cmd := &model.Command{
		Trigger: "fawkes",
		AutoComplete: true,
		AutoCompleteDesc: "Get insights of the user state",
		AutocompleteData: autocompleteData,
	}

	if err := p.API.RegisterCommand(cmd); err != nil {
		return err
	}
	p.API.LogDebug("plugin started")

	return nil
}

func (p *Plugin) ExecuteCommand(_ *plugin.Context, args *model.CommandArgs) (*model.CommandResponse, *model.AppError) {
	split := strings.Fields(args.Command)
	command := split[0]
	var parameters []string
	action := ""
	if len(split) > 1 {
		action = split[1]
	}
	if len(split) > 2 {
		parameters = split[2:]
	}

	if command != "/fawkes" {
		return &model.CommandResponse{}, nil
	}

	switch (action) {
	case "count-whitelisted":
		rows, err := p.Q().Select("count(*)").From("msteamssync_whitelisted_users").Query()
		if err != nil {
			return p.sendEphemeralAndExit(fmt.Sprintf("ERROR: %s", err), args)
		}
		defer rows.Close()

		var result int
		rows.Next()
		if err := rows.Scan(&result); err != nil {
			return p.sendEphemeralAndExit(fmt.Sprintf("ERROR: %s", err), args)
		}

		return p.sendEphemeralAndExit(fmt.Sprintf("There are %d users in the msteamssync_whitelisted_users table", result), args)
	case "count-lastconnectat":
		rows, err := p.Q().Select("count(*)").From("msteamssync_users").Where(sq.NotEq{"lastconnectat": 0}).Query()
		if err != nil {
			return p.sendEphemeralAndExit(fmt.Sprintf("ERROR: %s", err), args)
		}
		defer rows.Close()

		var result int
		rows.Next()
		if err := rows.Scan(&result); err != nil {
			return p.sendEphemeralAndExit(fmt.Sprintf("ERROR: %s", err), args)
		}

		return p.sendEphemeralAndExit(fmt.Sprintf("There are %d users in the msteamssync_users table with `lastconnectat != 0`", result), args)
	case "count-lastdisconnectat":
		rows, err := p.Q().Select("count(*)").From("msteamssync_users").Where(sq.NotEq{"lastdisconnectat": 0}).Query()
		if err != nil {
			return p.sendEphemeralAndExit(fmt.Sprintf("ERROR: %s", err), args)
		}
		defer rows.Close()

		var result int
		rows.Next()
		if err := rows.Scan(&result); err != nil {
			return p.sendEphemeralAndExit(fmt.Sprintf("ERROR: %s", err), args)
		}

		return p.sendEphemeralAndExit(fmt.Sprintf("There are %d users in the msteamssync_users table with `lastdisconnectat != 0`", result), args)
	case "user-info":
		if len(parameters) != 1 {
			return p.sendEphemeralAndExit("user-info must receive one \"username\" or \"email\" parameter", args)
		}

		email := parameters[0]

		var user *model.User
		var appErr *model.AppError
		user, appErr = p.API.GetUserByEmail(email)
		if appErr != nil {
			user, appErr = p.API.GetUserByUsername(email)
			if appErr != nil {
				return p.sendEphemeralAndExit(fmt.Sprintf("ERROR getting the user by email and username: %s", appErr.Error()), args)
			}
		}

		rows, err := p.Q().
			Select("msteamsuserid, token, lastconnectat, lastdisconnectat").
			From("msteamssync_users").
			Where(sq.Eq{"mmuserid": user.Id}).
			Query()
		if err != nil {
			return p.sendEphemeralAndExit(fmt.Sprintf("ERROR querying for msteamssync user: %s", err), args)
		}
		defer rows.Close()

		var mmTeamsUserID string
		var token string
		var lastConnectAt int
		var lastDisconnectAt int
		if !rows.Next() {
			return p.sendEphemeralAndExit(fmt.Sprintf("User %q not found in the msteamssync_users table", email), args)
		}
		if err := rows.Scan(&mmTeamsUserID, &token, &lastConnectAt, &lastDisconnectAt); err != nil {
			return p.sendEphemeralAndExit(fmt.Sprintf("ERROR scanning rows: %s", err), args)
		}

		var remoteID string
		if user.RemoteId != nil {
			remoteID = *user.RemoteId
		}

		hasToken := false
		if token != "" {
			hasToken = true
		}
		return p.sendEphemeralAndExit(fmt.Sprintf("User %q has\n - `mmTeamsUserID`: %s\n - `hasToken`: %v\n - `lastConnectAt`: %d\n - `lastDisconnectAt`: %d\n - `remoteID`: %s", email, mmTeamsUserID, hasToken, lastConnectAt, lastDisconnectAt, remoteID), args)
	case "channel-info":
		if len(parameters) != 1 {
			return p.sendEphemeralAndExit("channel-info must receive the channel ID", args)
		}

		channelID := parameters[0]

		channel, appErr := p.API.GetChannel(channelID)
		if appErr != nil {
			return p.sendEphemeralAndExit(fmt.Sprintf("ERROR getting the channel: %s", appErr.Error()), args)
		}

		return p.sendEphemeralAndExit(fmt.Sprintf(" - `Id`: %s\n - `name`: %s\n - `IsShared`: %v", channel.Id, channel.Name, channel.IsShared()), args)
	case "list-invites":
		rows, err := p.Q().
			Select("mmuserid, invitependingsince, invitelastsentat").
			From("msteamssync_invited_users").
			Query()
		if err != nil {
			return p.sendEphemeralAndExit(fmt.Sprintf("ERROR querying for invited users: %s", err), args)
		}
		defer rows.Close()

		invites := []map[string]any{}
		for rows.Next() {
			var mmUserID string
			var invitePendingSince int
			var inviteLastSentAt int
			if err := rows.Scan(&mmUserID, &invitePendingSince, &inviteLastSentAt); err != nil {
				return p.sendEphemeralAndExit(fmt.Sprintf("ERROR scanning row: %s", err), args)
			}

			invites = append(invites, map[string]any{
				"mmUserID": mmUserID,
				"invitePendingSince": invitePendingSince,
				"inviteLastSentAt": inviteLastSentAt,
			})
		}

		message := "Invite list:\n"
		for _, invite := range invites {
			message += fmt.Sprintf(
				" - `mmUserID`: %s :: `invitePendingSince`: %d :: `inviteLastSentAt`: %d\n",
				invite["mmUserID"],
				invite["invitePendingSince"],
				invite["inviteLastSentAt"],
			)
		}

		return p.sendEphemeralAndExit(message, args)
	case "delete-invite":
		return p.sendEphemeralAndExit("Not implemented yet", args)
	default:
		p.sendEphemeral(fmt.Sprintf("Invalid command %q", action), args)
		return &model.CommandResponse{}, nil
	}
}

func (p *Plugin) sendEphemeral(message string, args *model.CommandArgs) {
	_ = p.API.SendEphemeralPost(args.UserId, &model.Post{
		Message: message,
		UserId: args.UserId,
		ChannelId: args.ChannelId,
	})
}

func (p *Plugin) sendEphemeralAndExit(message string, args *model.CommandArgs) (*model.CommandResponse, *model.AppError) {
	p.sendEphemeral(message, args)
	return &model.CommandResponse{}, nil
}

// See https://developers.mattermost.com/extend/plugins/server/reference/