/*
  EEPROM.ino, Example for the AutoConnect library.
  Copyright (c) 2020, Hieromon Ikasamo
  https://github.com/Hieromon/AutoConnect
  This software is released under the MIT License.
  https://opensource.org/licenses/MIT

  This example demonstrates how allocates and handles the custom
  configuration for the Sketch.
  When Sketch stores the own configuration data in the EEPROM, it must
  avoid conflict with the credentials stored by AutoConnect.
  AutoConnectConfig::boundayOffet designation helps with the conflict,
  but it is inadequate. Sketch uses AutoConnect::getCredentialSize to
  get the size of the actual EEPROM area that should be handled for the
  own custom data I/O.  
*/

#ifndef ARDUINO_ARCH_ESP8266
#error "EEPROM.ino sketch is available for ESP8266 only."
#endif

#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>
#include <EEPROM.h>
#include <AutoConnect.h>

ESP8266WebServer  server;
AutoConnect       portal(server);
AutoConnectConfig config;

const char AUX_EEPROM_IO[] PROGMEM = R"(
[
  {
    "title": "EEPROM",
    "uri": "/",
    "menu": true,
    "element": [
      {
        "name": "data1",
        "type": "ACInput",
        "label": "DATA1",
        "global": true
      },
      {
        "name": "data2",
        "type": "ACInput",
        "label": "DATA2",
        "global": true
      },
      {
        "name": "data3",
        "type": "ACInput",
        "label": "DATA3",
        "global": true
      },
      {
        "name": "write",
        "type": "ACSubmit",
        "value": "WRITE",
        "uri": "/eeprom",
        "global": true
      }
    ]
  },
  {
    "title": "EEPROM",
    "uri": "/eeprom",
    "menu": false,
    "element": [
      {
        "name": "data1",
        "type": "ACText",
        "format": "DATA1: %s",
        "posterior": "br",
        "global": true
      },
      {
        "name": "data2",
        "type": "ACText",
        "format": "DATA2: %s",
        "posterior": "br",
        "global": true
      },
      {
        "name": "data3",
        "type": "ACText",
        "format": "DATA3: %s",
        "posterior": "br",
        "global": true
      }
    ]
  }
]
)";

// Defines the custom data should be stored in EEPROM.
typedef struct {
  char  data1[8];
  char  data2[8];
  char  data3[8];
} EEPROM_CONFIG_t;

String toString(char* c, uint8_t length) {
  String  r;
  while (length-- && *c) {
    r += (isAlphaNumeric(*c) ? String(*c) : String(*c, HEX));
    c++;
  }
  return r;
}

// Read from EEPROM
String onEEPROM(AutoConnectAux& page, PageArgument& args) {
  EEPROM_CONFIG_t eepromConfig;

  // The actual area size of the EEPROM region to be given to
  // EEPROM.begin is the sum of the size of the own custom data and
  // the size of the currently stored AutoConnect credentials.
  // eg.
  //   sizeof(EEPROM_CONFIG_t) + portal.getCredentialSize()
  EEPROM.begin(sizeof(EEPROM_CONFIG_t) + portal.getCredentialSize());
  EEPROM.get<EEPROM_CONFIG_t>(0, eepromConfig);
  EEPROM.end();

  page["data1"].value = toString(eepromConfig.data1, sizeof(EEPROM_CONFIG_t::data1));
  page["data2"].value = toString(eepromConfig.data2, sizeof(EEPROM_CONFIG_t::data2));
  page["data3"].value = toString(eepromConfig.data3, sizeof(EEPROM_CONFIG_t::data3));
  return String();
}

// Write to EEPROM
String onEEPROMWrite(AutoConnectAux& page, PageArgument& args) {
  EEPROM_CONFIG_t eepromConfig;

  strncpy(eepromConfig.data1, page["data1"].value.c_str(), sizeof(EEPROM_CONFIG_t::data1));
  strncpy(eepromConfig.data2, page["data2"].value.c_str(), sizeof(EEPROM_CONFIG_t::data2));
  strncpy(eepromConfig.data3, page["data3"].value.c_str(), sizeof(EEPROM_CONFIG_t::data3));

  EEPROM.begin(sizeof(EEPROM_CONFIG_t) + portal.getCredentialSize());
  EEPROM.put<EEPROM_CONFIG_t>(0, eepromConfig);
  EEPROM.commit();
  EEPROM.end();
  return String();
}

void setup() {
  delay(1000);
  Serial.begin(115200);
  Serial.println();

  portal.load(FPSTR(AUX_EEPROM_IO));
  portal.on("/", onEEPROM);
  portal.on("/eeprom", onEEPROMWrite);

  // Specifies to shift the AutoConnect credentials with the custom data region size.
  config.boundaryOffset = sizeof(EEPROM_CONFIG_t);
  portal.config(config);

  portal.begin();
}

void loop() {
  portal.handleClient();
}