/*
    ESP8285 helper class for the Challenger RP2040 WiFi boards

    Copyright (c) 2021 P. Oldberg <pontus@ilabs.se>

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

#include <Arduino.h>
#include <Ilabs2040WiFiClass.h>

Ilabs2040WiFiClass::Ilabs2040WiFiClass() {
    pinMode(PIN_ESP_RESET, OUTPUT);
    digitalWrite(PIN_ESP_RESET, LOW);     // Hold ESP8285 in reset
    pinMode(PIN_ESP_MODE, OUTPUT);
    digitalWrite(PIN_ESP_MODE, HIGH);     // Prepare for normal start
}

// Do a HW reset by applying a low pulse to the reset line for 1mSec
void Ilabs2040WiFiClass::doHWReset() {
    digitalWrite(PIN_ESP_RESET, LOW);     // Hold ESP8285 in reset
    delay(1);
    digitalWrite(PIN_ESP_RESET, HIGH);    // Release ESP8285 reset
}

// Set the mode flag high to indicate normal run operation and do a HW
// reset.
void Ilabs2040WiFiClass::runReset() {   // Prepare ESP8285 for normal op
    digitalWrite(PIN_ESP_MODE, HIGH);     // Prepare for normal start
    doHWReset();
}

// Set the mode flag low to indicate flash operation and do a HW
// reset.
void Ilabs2040WiFiClass::flashReset() { // Prepare ESP8285 for flashing
    digitalWrite(PIN_ESP_MODE, LOW);      // Prepare for normal start
    doHWReset();
}

// Wait for the modem to reply with a "ready" prompt. This can be done
// after a sw or hw reset have been performed to ensure that the AT
// interpreter is up and running.
bool Ilabs2040WiFiClass::waitForReady() {
    int timeout = 20;                     // Aprox max 2 sec

    ESP_SERIAL_PORT.begin(DEFAULT_ESP8285_BAUDRATE);
    ESP_SERIAL_PORT.setTimeout(100);
    String rdy = ESP_SERIAL_PORT.readStringUntil('\n');
    while (!rdy.startsWith("ready") && timeout--) {
        rdy = ESP_SERIAL_PORT.readStringUntil('\n');
    }
    ESP_SERIAL_PORT.setTimeout(1000);   // Reset default timeout to 1000
    if (timeout) {
        return true;
    }
    return false;
}

// Reset the ESP8285 and wait for the "ready" prompt to be returned.
bool Ilabs2040WiFiClass::reset() {
    runReset();
    return waitForReady();
}

// Checks to see if the modem responds to the "AT" poll command.
bool Ilabs2040WiFiClass::isAlive() {
    int timeout = 5;

    ESP_SERIAL_PORT.setTimeout(250);
    ESP_SERIAL_PORT.println(F("AT"));
    String rdy = ESP_SERIAL_PORT.readStringUntil('\n');
    while (!rdy.startsWith(F("OK")) && timeout--) {
        rdy = ESP_SERIAL_PORT.readStringUntil('\n');
    }
    ESP_SERIAL_PORT.setTimeout(1000);

    if (timeout) {
        return true;
    }
    return false;
}

// Change the baud rate of the ESP8285 as well as the local UART.
// No checking is done on the input baud rate so the user must know what
// baud rates are valid. The function ends by checking if the ESP8285 is
// reachable by doing an "AT" poll.
bool Ilabs2040WiFiClass::changeBaudRate(int baud) {
    ESP_SERIAL_PORT.print(F("AT+UART_CUR="));
    ESP_SERIAL_PORT.print(baud);
    ESP_SERIAL_PORT.println(F(",8,1,0,0"));
    delay(100);
    ESP_SERIAL_PORT.end();
    ESP_SERIAL_PORT.begin(baud);
    return isAlive();
}

Ilabs2040WiFiClass Ilabs2040WiFi;