/*
 * Copyright (C) 2004-2020 ZNC, see the NOTICE file for details.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <znc/User.h>
#include <znc/IRCNetwork.h>
#include <time.h>

#define SIMPLE_AWAY_DEFAULT_REASON "Auto away at %awaytime%"
#define SIMPLE_AWAY_DEFAULT_TIME 60

class CSimpleAway;

class CSimpleAwayJob : public CTimer {
  public:
    CSimpleAwayJob(CModule* pModule, unsigned int uInterval,
                   unsigned int uCycles, const CString& sLabel,
                   const CString& sDescription)
        : CTimer(pModule, uInterval, uCycles, sLabel, sDescription) {}

    ~CSimpleAwayJob() override {}

  protected:
    void RunJob() override;
};

class CSimpleAway : public CModule {
  private:
    CString m_sReason;
    unsigned int m_iAwayWait;
    unsigned int m_iMinClients;
    bool m_bClientSetAway;
    bool m_bWeSetAway;

  public:
    MODCONSTRUCTOR(CSimpleAway) {
        m_sReason = SIMPLE_AWAY_DEFAULT_REASON;
        m_iAwayWait = SIMPLE_AWAY_DEFAULT_TIME;
        m_iMinClients = 1;
        m_bClientSetAway = false;
        m_bWeSetAway = false;

        AddHelpCommand();
        AddCommand("Reason", t_d("[<text>]"),
                   t_d("Prints or sets the away reason (%awaytime% is replaced "
                       "with the time you were set away, supports "
                       "substitutions using ExpandString)"),
                   [=](const CString& sLine) { OnReasonCommand(sLine); });
        AddCommand(
            "Timer", "",
            t_d("Prints the current time to wait before setting you away"),
            [=](const CString& sLine) { OnTimerCommand(sLine); });
        AddCommand("SetTimer", t_d("<seconds>"),
                   t_d("Sets the time to wait before setting you away"),
                   [=](const CString& sLine) { OnSetTimerCommand(sLine); });
        AddCommand("DisableTimer", "",
                   t_d("Disables the wait time before setting you away"),
                   [=](const CString& sLine) { OnDisableTimerCommand(sLine); });
        AddCommand(
            "MinClients", "",
            t_d("Get or set the minimum number of clients before going away"),
            [=](const CString& sLine) { OnMinClientsCommand(sLine); });
    }

    ~CSimpleAway() override {}

    bool OnLoad(const CString& sArgs, CString& sMessage) override {
        CString sReasonArg;

        // Load AwayWait
        CString sFirstArg = sArgs.Token(0);
        if (sFirstArg.Equals("-notimer")) {
            SetAwayWait(0);
            sReasonArg = sArgs.Token(1, true);
        } else if (sFirstArg.Equals("-timer")) {
            SetAwayWait(sArgs.Token(1).ToUInt());
            sReasonArg = sArgs.Token(2, true);
        } else {
            CString sAwayWait = GetNV("awaywait");
            if (!sAwayWait.empty()) SetAwayWait(sAwayWait.ToUInt(), false);
            sReasonArg = sArgs;
        }

        // Load Reason
        if (!sReasonArg.empty()) {
            SetReason(sReasonArg);
        } else {
            CString sSavedReason = GetNV("reason");
            if (!sSavedReason.empty()) SetReason(sSavedReason, false);
        }

        // MinClients
        CString sMinClients = GetNV("minclients");
        if (!sMinClients.empty()) SetMinClients(sMinClients.ToUInt(), false);

        // Set away on load, required if loaded via webadmin
        if (GetNetwork()->IsIRCConnected() && MinClientsConnected())
            SetAway(false);

        return true;
    }

    void OnIRCConnected() override {
        if (MinClientsConnected())
            SetBack();
        else
            SetAway(false);
    }

    void OnClientLogin() override {
        if (MinClientsConnected()) SetBack();
    }

    void OnClientDisconnect() override {
        /* There might still be other clients */
        if (!MinClientsConnected()) SetAway();
    }

    void OnReasonCommand(const CString& sLine) {
        CString sReason = sLine.Token(1, true);

        if (!sReason.empty()) {
            SetReason(sReason);
            PutModule(t_s("Away reason set"));
        } else {
            PutModule(t_f("Away reason: {1}")(m_sReason));
            PutModule(t_f("Current away reason would be: {1}")(ExpandReason()));
        }
    }

    void OnTimerCommand(const CString& sLine) {
        PutModule(t_p("Current timer setting: 1 second",
                      "Current timer setting: {1} seconds",
                      m_iAwayWait)(m_iAwayWait));
    }

    void OnSetTimerCommand(const CString& sLine) {
        SetAwayWait(sLine.Token(1).ToUInt());

        if (m_iAwayWait == 0)
            PutModule(t_s("Timer disabled"));
        else
            PutModule(t_p("Timer set to 1 second", "Timer set to: {1} seconds",
                          m_iAwayWait)(m_iAwayWait));
    }

    void OnDisableTimerCommand(const CString& sLine) {
        SetAwayWait(0);
        PutModule(t_s("Timer disabled"));
    }

    void OnMinClientsCommand(const CString& sLine) {
        if (sLine.Token(1).empty()) {
            PutModule(t_f("Current MinClients setting: {1}")(m_iMinClients));
        } else {
            SetMinClients(sLine.Token(1).ToUInt());
            PutModule(t_f("MinClients set to {1}")(m_iMinClients));
        }
    }

    EModRet OnUserRawMessage(CMessage& msg) override {
        if (!msg.GetCommand().Equals("AWAY")) return CONTINUE;

        // If a client set us away, we don't touch that away message
        m_bClientSetAway = !msg.GetParam(0).Trim_n(" ").empty();
        m_bWeSetAway = false;

        return CONTINUE;
    }

    void SetAway(bool bTimer = true) {
        if (bTimer) {
            RemTimer("simple_away");
            AddTimer(new CSimpleAwayJob(this, m_iAwayWait, 1, "simple_away",
                                        "Sets you away after detach"));
        } else {
            if (!m_bClientSetAway) {
                PutIRC("AWAY :" + ExpandReason());
                m_bWeSetAway = true;
            }
        }
    }

    void SetBack() {
        RemTimer("simple_away");
        if (m_bWeSetAway) {
            PutIRC("AWAY");
            m_bWeSetAway = false;
        }
    }

  private:
    bool MinClientsConnected() {
        return GetNetwork()->GetClients().size() >= m_iMinClients;
    }

    CString ExpandReason() {
        CString sReason = m_sReason;
        if (sReason.empty()) sReason = SIMPLE_AWAY_DEFAULT_REASON;

        time_t iTime = time(nullptr);
        CString sTime = CUtils::CTime(iTime, "Etc/UTC") + " UTC";
        sReason.Replace("%awaytime%", sTime);
        sReason = ExpandString(sReason);
        sReason.Replace("%s", sTime);  // Backwards compatibility with previous
                                       // syntax, where %s was substituted with
                                       // sTime. ZNC <= 1.6.x

        return sReason;
    }

    /* Settings */
    void SetReason(CString& sReason, bool bSave = true) {
        if (bSave) SetNV("reason", sReason);
        m_sReason = sReason;
    }

    void SetAwayWait(unsigned int iAwayWait, bool bSave = true) {
        if (bSave) SetNV("awaywait", CString(iAwayWait));
        m_iAwayWait = iAwayWait;
    }

    void SetMinClients(unsigned int iMinClients, bool bSave = true) {
        if (bSave) SetNV("minclients", CString(iMinClients));
        m_iMinClients = iMinClients;
    }
};

void CSimpleAwayJob::RunJob() { ((CSimpleAway*)GetModule())->SetAway(false); }

template <>
void TModInfo<CSimpleAway>(CModInfo& Info) {
    Info.SetWikiPage("simple_away");
    Info.SetHasArgs(true);
    Info.SetArgsHelpText(
        Info.t_s("You might enter up to 3 arguments, like -notimer awaymessage "
                 "or -timer 5 awaymessage."));
}

NETWORKMODULEDEFS(CSimpleAway,
                  t_s("This module will automatically set you away on IRC "
                      "while you are disconnected from the bouncer."))
