/**
 * @file       TinyGsmClientBG96.h
 * @author     Volodymyr Shymanskyy
 * @license    LGPL-3.0
 * @copyright  Copyright (c) 2016 Volodymyr Shymanskyy
 * @date       Apr 2018
 */

#ifndef SRC_TINYGSMCLIENTBG96_H_
#define SRC_TINYGSMCLIENTBG96_H_
// #pragma message("TinyGSM:  TinyGsmClientBG96")

// #define TINY_GSM_DEBUG Serial

#define TINY_GSM_MUX_COUNT 12

#include "TinyGsmCommon.h"

#define GSM_NL "\r\n"
static const char GSM_OK[] TINY_GSM_PROGMEM        = "OK" GSM_NL;
static const char GSM_ERROR[] TINY_GSM_PROGMEM     = "ERROR" GSM_NL;
static const char GSM_CME_ERROR[] TINY_GSM_PROGMEM = GSM_NL "+CME ERROR:";

enum RegStatus {
  REG_NO_RESULT    = -1,
  REG_UNREGISTERED = 0,
  REG_SEARCHING    = 2,
  REG_DENIED       = 3,
  REG_OK_HOME      = 1,
  REG_OK_ROAMING   = 5,
  REG_UNKNOWN      = 4,
};

class TinyGsmBG96
    : public TinyGsmModem<TinyGsmBG96, READ_AND_CHECK_SIZE, TINY_GSM_MUX_COUNT> {
  friend class TinyGsmModem<TinyGsmBG96, READ_AND_CHECK_SIZE, TINY_GSM_MUX_COUNT>;

  /*
   * Inner Client
   */
 public:
  class GsmClientBG96 : public GsmClient {
    friend class TinyGsmBG96;

   public:
    GsmClientBG96() {}

    explicit GsmClientBG96(TinyGsmBG96& modem, uint8_t mux = 1) {
      init(&modem, mux);
    }

    bool init(TinyGsmBG96* modem, uint8_t mux = 1) {
      this->at       = modem;
      this->mux      = mux;
      sock_available = 0;
      prev_check     = 0;
      sock_connected = false;
      got_data       = false;

      at->sockets[mux] = this;

      return true;
    }

   public:
    virtual int connect(const char* host, uint16_t port, int timeout_s) {
      stop();
      TINY_GSM_YIELD();
      rx.clear();
      sock_connected = at->modemConnect(host, port, mux, false, timeout_s);
      return sock_connected;
    }
    int connect(IPAddress ip, uint16_t port, int timeout_s) {
      return connect(TinyGsmStringFromIp(ip).c_str(), port, timeout_s);
    }
    int connect(const char* host, uint16_t port) override {
      return connect(host, port, 75);
    }
    int connect(IPAddress ip, uint16_t port) override {
      return connect(ip, port, 75);
    }

    void stop(uint32_t maxWaitMs) {
      dumpModemBuffer(maxWaitMs);
      at->sendAT(GF("+QICLOSE="), mux);
      sock_connected = false;
      at->waitResponse();
    }
    void stop() override {
      stop(15000L);
    }

    /*
     * Extended API
     */

    String remoteIP() TINY_GSM_ATTR_NOT_IMPLEMENTED;
  };

  /*
   * Inner Secure Client
   */

  /*
  class GsmClientSecureBG96 : public GsmClientBG96
  {
  public:
    GsmClientSecure() {}

    GsmClientSecure(TinyGsmBG96& modem, uint8_t mux = 1)
     : public GsmClient(modem, mux)
    {}


  public:
    int connect(const char* host, uint16_t port, int timeout_s) {
      stop();
      TINY_GSM_YIELD();
      rx.clear();
      sock_connected = at->modemConnect(host, port, mux, true, timeout_s);
      return sock_connected;
    }
  };
  */

  /*
   * Constructor
   */
 public:
  explicit TinyGsmBG96(Stream& stream) : stream(stream) {
    memset(sockets, 0, sizeof(sockets));
  }

  /*
   * Basic functions
   */
 protected:
  bool initImpl(const char* pin = NULL) {
    DBG(GF("### TinyGSM Version:"), TINYGSM_VERSION);

    if (!testAT()) { return false; }

    sendAT(GF("E0"));  // Echo Off
    if (waitResponse() != 1) { return false; }

#ifdef TINY_GSM_DEBUG
    sendAT(GF("+CMEE=2"));  // turn on verbose error codes
#else
    sendAT(GF("+CMEE=0"));  // turn off error codes
#endif
    waitResponse();

    DBG(GF("### Modem:"), getModemName());

    // Enable automatic time zone update
    sendAT(GF("+CTZU=1"));
    if (waitResponse(10000L) != 1) { return false; }

    int ret = getSimStatus();
    // if the sim isn't ready and a pin has been provided, try to unlock the sim
    if (ret != SIM_READY && pin != NULL && strlen(pin) > 0) {
      simUnlock(pin);
      return (getSimStatus() == SIM_READY);
    } else {
      // if the sim is ready, or it's locked but no pin has been provided,
      // return true
      return (ret == SIM_READY || ret == SIM_LOCKED);
    }
  }

  bool thisHasSSL() {
    return false;  // TODO(?): Add SSL support
  }

  bool thisHasWifi() {
    return false;
  }

  bool thisHasGPRS() {
    return true;
  }

  /*
   * Power functions
   */
 protected:
  bool restartImpl() {
    if (!testAT()) { return false; }
    sendAT(GF("+CFUN=1,1"));
    if (waitResponse(60000L, GF("POWERED DOWN")) != 1) { return false; }
    waitResponse(5000L, GF("RDY"));
    return init();
  }

  bool powerOffImpl() {
    sendAT(GF("+QPOWD=1"));
    waitResponse(300);  // returns OK first
    return waitResponse(300, GF("POWERED DOWN")) == 1;
  }

  // When entering into sleep mode is enabled, DTR is pulled up, and WAKEUP_IN
  // is pulled up, the module can directly enter into sleep mode.If entering
  // into sleep mode is enabled, DTR is pulled down, and WAKEUP_IN is pulled
  // down, there is a need to pull the DTR pin and the WAKEUP_IN pin up first,
  // and then the module can enter into sleep mode.
  bool sleepEnableImpl(bool enable = true) {
    sendAT(GF("+QSCLK="), enable);
    return waitResponse() == 1;
  }

  /*
   * SIM card functions
   */
 protected:
  String getSimCCIDImpl() {
    sendAT(GF("+QCCID"));
    if (waitResponse(GF(GSM_NL "+QCCID:")) != 1) { return ""; }
    String res = stream.readStringUntil('\n');
    waitResponse();
    res.trim();
    return res;
  }

  /*
   * Generic network functions
   */
 public:
  RegStatus getRegistrationStatus() {
    return (RegStatus)getRegistrationStatusXREG("CREG");
  }

 protected:
  bool isNetworkConnectedImpl() {
    RegStatus s = getRegistrationStatus();
    return (s == REG_OK_HOME || s == REG_OK_ROAMING);
  }

  /*
   * GPRS functions
   */
 protected:
  bool gprsConnectImpl(const char* apn, const char* user = NULL,
                       const char* pwd = NULL) {
    gprsDisconnect();

    // Configure the TCPIP Context
    sendAT(GF("+QICSGP=1,1,\""), apn, GF("\",\""), user, GF("\",\""), pwd,
           GF("\""));
    if (waitResponse() != 1) { return false; }

    // Activate GPRS/CSD Context
    sendAT(GF("+QIACT=1"));
    if (waitResponse(150000L) != 1) { return false; }

    // Attach to Packet Domain service - is this necessary?
    sendAT(GF("+CGATT=1"));
    if (waitResponse(60000L) != 1) { return false; }

    return true;
  }

  bool gprsDisconnectImpl() {
    sendAT(GF("+QIDEACT=1"));  // Deactivate the bearer context
    if (waitResponse(40000L) != 1) { return false; }

    return true;
  }

  /*
   * IP Address functions
   */
 protected:
  // Can follow all of the IP functions from the template

  /*
   * Phone Call functions
   */
 protected:
  // Can follow all of the phone call functions from the template

  /*
   * Messaging functions
   */
 protected:
  // Follows all messaging functions per template

  /*
   * Location functions
   */
 protected:
  String getGsmLocationImpl() TINY_GSM_ATTR_NOT_AVAILABLE;

  /*
   * GPS location functions
   */
 public:
  // No functions of this type supported

  /*
   * Time functions
   */
 protected:
  // Can follow the standard CCLK function in the template

  /*
   * Battery & temperature functions
   */
 protected:
  float getTemperatureImpl() TINY_GSM_ATTR_NOT_AVAILABLE;

  /*
   * Client related functions
   */
 protected:
  bool modemConnect(const char* host, uint16_t port, uint8_t mux,
                    bool ssl = false, int timeout_s = 20) {
    if (ssl) { DBG("SSL not yet supported on this module!"); }
    int      rsp;
    uint32_t timeout_ms = ((uint32_t)timeout_s) * 1000;

    // <PDPcontextID>(1-16), <connectID>(0-11),
    // "TCP/UDP/TCP LISTENER/UDPSERVICE", "<IP_address>/<domain_name>",
    // <remote_port>,<local_port>,<access_mode>(0-2; 0=buffer)
    sendAT(GF("+QIOPEN=1,"), mux, GF(",\""), GF("TCP"), GF("\",\""), host,
           GF("\","), port, GF(",0,0"));
    waitResponse();

    if (waitResponse(timeout_ms, GF(GSM_NL "+QIOPEN:")) != 1) { return false; }

    if (stream.readStringUntil(',').toInt() != mux) { return false; }
    // Read status
    rsp = stream.readStringUntil('\n').toInt();

    return (0 == rsp);
  }

  int16_t modemSend(const void* buff, size_t len, uint8_t mux) {
    sendAT(GF("+QISEND="), mux, ',', (uint16_t)len);
    if (waitResponse(GF(">")) != 1) { return 0; }
    stream.write(reinterpret_cast<const uint8_t*>(buff), len);
    stream.flush();
    if (waitResponse(GF(GSM_NL "SEND OK")) != 1) { return 0; }
    // TODO(?): Wait for ACK? AT+QISEND=id,0
    return len;
  }

  size_t modemRead(size_t size, uint8_t mux) {
    sendAT(GF("+QIRD="), mux, ',', (uint16_t)size);
    if (waitResponse(GF("+QIRD:")) != 1) { return 0; }
    int len = stream.readStringUntil('\n').toInt();

    for (int i = 0; i < len; i++) { moveCharFromStreamToFifo(mux); }
    waitResponse();
    DBG("### READ:", len, "from", mux);
    sockets[mux]->sock_available = modemGetAvailable(mux);
    return len;
  }

  size_t modemGetAvailable(uint8_t mux) {
    sendAT(GF("+QIRD="), mux, GF(",0"));
    size_t result = 0;
    if (waitResponse(GF("+QIRD:")) == 1) {
      streamSkipUntil(',');  // Skip total received
      streamSkipUntil(',');  // Skip have read
      result = stream.readStringUntil('\n').toInt();
      if (result) { DBG("### DATA AVAILABLE:", result, "on", mux); }
      waitResponse();
    }
    if (!result) { sockets[mux]->sock_connected = modemGetConnected(mux); }
    return result;
  }

  bool modemGetConnected(uint8_t mux) {
    sendAT(GF("+QISTATE=1,"), mux);
    // +QISTATE: 0,"TCP","151.139.237.11",80,5087,4,1,0,0,"uart1"

    if (waitResponse(GF("+QISTATE:")) != 1) { return false; }

    streamSkipUntil(',');                           // Skip mux
    streamSkipUntil(',');                           // Skip socket type
    streamSkipUntil(',');                           // Skip remote ip
    streamSkipUntil(',');                           // Skip remote port
    streamSkipUntil(',');                           // Skip local port
    int res = stream.readStringUntil(',').toInt();  // socket state

    waitResponse();

    // 0 Initial, 1 Opening, 2 Connected, 3 Listening, 4 Closing
    return 2 == res;
  }

  /*
   * Utilities
   */
 public:
  // TODO(vshymanskyy): Optimize this!
  uint8_t waitResponse(uint32_t timeout_ms, String& data,
                       GsmConstStr r1 = GFP(GSM_OK),
                       GsmConstStr r2 = GFP(GSM_ERROR),
                       GsmConstStr r3 = GFP(GSM_CME_ERROR),
                       GsmConstStr r4 = NULL, GsmConstStr r5 = NULL) {
    /*String r1s(r1); r1s.trim();
    String r2s(r2); r2s.trim();
    String r3s(r3); r3s.trim();
    String r4s(r4); r4s.trim();
    String r5s(r5); r5s.trim();
    DBG("### ..:", r1s, ",", r2s, ",", r3s, ",", r4s, ",", r5s);*/
    data.reserve(64);
    uint8_t  index       = 0;
    uint32_t startMillis = millis();
    do {
      TINY_GSM_YIELD();
      while (stream.available() > 0) {
        TINY_GSM_YIELD();
        int a = stream.read();
        if (a <= 0) continue;  // Skip 0x00 bytes, just in case
        data += static_cast<char>(a);
        if (r1 && data.endsWith(r1)) {
          index = 1;
          goto finish;
        } else if (r2 && data.endsWith(r2)) {
          index = 2;
          goto finish;
        } else if (r3 && data.endsWith(r3)) {
          index = 3;
          goto finish;
        } else if (r4 && data.endsWith(r4)) {
          index = 4;
          goto finish;
        } else if (r5 && data.endsWith(r5)) {
          index = 5;
          goto finish;
        } else if (data.endsWith(GF(GSM_NL "+QIURC:"))) {
          stream.readStringUntil('\"');
          String urc = stream.readStringUntil('\"');
          stream.readStringUntil(',');
          if (urc == "recv") {
            int mux = stream.readStringUntil('\n').toInt();
            DBG("### URC RECV:", mux);
            if (mux >= 0 && mux < TINY_GSM_MUX_COUNT && sockets[mux]) {
              sockets[mux]->got_data = true;
            }
          } else if (urc == "closed") {
            int mux = stream.readStringUntil('\n').toInt();
            DBG("### URC CLOSE:", mux);
            if (mux >= 0 && mux < TINY_GSM_MUX_COUNT && sockets[mux]) {
              sockets[mux]->sock_connected = false;
            }
          } else {
            stream.readStringUntil('\n');
          }
          data = "";
        }
      }
    } while (millis() - startMillis < timeout_ms);
  finish:
    if (!index) {
      data.trim();
      if (data.length()) { DBG("### Unhandled:", data); }
      data = "";
    }
    // data.replace(GSM_NL, "/");
    // DBG('<', index, '>', data);
    return index;
  }

  uint8_t waitResponse(uint32_t timeout_ms, GsmConstStr r1 = GFP(GSM_OK),
                       GsmConstStr r2 = GFP(GSM_ERROR),
                       GsmConstStr r3 = GFP(GSM_CME_ERROR),
                       GsmConstStr r4 = NULL, GsmConstStr r5 = NULL) {
    String data;
    return waitResponse(timeout_ms, data, r1, r2, r3, r4, r5);
  }

  uint8_t waitResponse(GsmConstStr r1 = GFP(GSM_OK),
                       GsmConstStr r2 = GFP(GSM_ERROR),
                       GsmConstStr r3 = GFP(GSM_CME_ERROR),
                       GsmConstStr r4 = NULL, GsmConstStr r5 = NULL) {
    return waitResponse(1000, r1, r2, r3, r4, r5);
  }

 protected:
  Stream&        stream;
  GsmClientBG96* sockets[TINY_GSM_MUX_COUNT];
  const char*    gsmNL = GSM_NL;
};

#endif  // SRC_TINYGSMCLIENTBG96_H_