/*

RELAY MODULE

Copyright (C) 2016-2017 by Xose Pérez <xose dot perez at gmail dot com>

*/

#include <EEPROM.h>
#include <ArduinoJson.h>
#include <vector>
#include <functional>

typedef struct {
    unsigned char pin;
    bool reverse;
} relay_t;
std::vector<relay_t> _relays;

#ifdef SONOFF_DUAL
    unsigned char dualRelayStatus = 0;
#endif

bool recursive = false;

// -----------------------------------------------------------------------------
// RELAY
// -----------------------------------------------------------------------------

String relayString() {
    DynamicJsonBuffer jsonBuffer;
    JsonObject& root = jsonBuffer.createObject();
    JsonArray& relay = root.createNestedArray("relayStatus");
    for (unsigned char i=0; i<relayCount(); i++) {
        relay.add(relayStatus(i));
    }
    String output;
    root.printTo(output);
    return output;
}

bool relayStatus(unsigned char id) {
    #ifdef SONOFF_DUAL
        if (id >= 2) return false;
        return ((dualRelayStatus & (1 << id)) > 0);
    #else
        if (id >= _relays.size()) return false;
        bool status = (digitalRead(_relays[id].pin) == HIGH);
        return _relays[id].reverse ? !status : status;
    #endif
}

bool relayStatus(unsigned char id, bool status, bool report) {

    if (id >= _relays.size()) return false;

    bool changed = false;

    if (relayStatus(id) != status) {

        DEBUG_MSG("[RELAY] %d => %s\n", id, status ? "ON" : "OFF");
        changed = true;

        #ifdef SONOFF_DUAL

            dualRelayStatus ^= (1 << id);
            Serial.flush();
            Serial.write(0xA0);
            Serial.write(0x04);
            Serial.write(dualRelayStatus);
            Serial.write(0xA1);
            Serial.flush();

        #else
            digitalWrite(_relays[id].pin, _relays[id].reverse ? !status : status);
        #endif

        if (report) relayMQTT(id);
        if (!recursive) {
            relaySync(id);
            relaySave();
            relayWS();
        }

        #ifdef ENABLE_DOMOTICZ
            relayDomoticzSend(id);
        #endif

    }

    return changed;

}

bool relayStatus(unsigned char id, bool status) {
    if (id >= _relays.size()) return false;
    return relayStatus(id, status, true);
}

void relaySync(unsigned char id) {

    if (_relays.size() > 1) {

        recursive = true;

        byte relaySync = getSetting("relaySync", RELAY_SYNC).toInt();
        bool status = relayStatus(id);

        // If RELAY_SYNC_SAME all relays should have the same state
        if (relaySync == RELAY_SYNC_SAME) {
            for (unsigned short i=0; i<_relays.size(); i++) {
                if (i != id) relayStatus(i, status);
            }

        // If NONE_OR_ONE or ONE and setting ON we should set OFF all the others
        } else if (status) {
            if (relaySync != RELAY_SYNC_ANY) {
                for (unsigned short i=0; i<_relays.size(); i++) {
                    if (i != id) relayStatus(i, false);
                }
            }

        // If ONLY_ONE and setting OFF we should set ON the other one
        } else {
            if (relaySync == RELAY_SYNC_ONE) {
                unsigned char i = (id + 1) % _relays.size();
                relayStatus(i, true);
            }
        }

        recursive = false;

    }

}

void relaySave() {
    unsigned char bit = 1;
    unsigned char mask = 0;
    for (unsigned int i=0; i < _relays.size(); i++) {
        if (relayStatus(i)) mask += bit;
        bit += bit;
    }
    EEPROM.write(0, mask);
    EEPROM.commit();
}

void relayRetrieve() {
    recursive = true;
    unsigned char bit = 1;
    unsigned char mask = EEPROM.read(0);
    for (unsigned int i=0; i < _relays.size(); i++) {
        relayStatus(i, ((mask & bit) == bit));
        bit += bit;
    }
    recursive = false;
}

void relayToggle(unsigned char id) {
    if (id >= _relays.size()) return;
    relayStatus(id, !relayStatus(id));
}

unsigned char relayCount() {
    return _relays.size();
}

//------------------------------------------------------------------------------
// REST API
//------------------------------------------------------------------------------

void relaySetupAPI() {

    // API entry points (protected with apikey)
    for (unsigned int relayID=0; relayID<relayCount(); relayID++) {

        char url[15];
        sprintf(url, "/api/relay/%d", relayID);

        char key[10];
        sprintf(key, "relay%d", relayID);

        apiRegister(url, key,
            [relayID](char * buffer, size_t len) {
				snprintf(buffer, len, "%d", relayStatus(relayID) ? 1 : 0);
            },
            [relayID](const char * payload) {
                unsigned int value = payload[0] - '0';
                if (value == 2) {
                    relayToggle(relayID);
                } else {
                    relayStatus(relayID, value == 1);
                }
            });

    }

}

//------------------------------------------------------------------------------
// WebSockets
//------------------------------------------------------------------------------

void relayWS() {
    String output = relayString();
    wsSend(output.c_str());
}


//------------------------------------------------------------------------------
// Domoticz
//------------------------------------------------------------------------------

#if ENABLE_DOMOTICZ

void relayDomoticzSend(unsigned int relayID) {
    char buffer[15];
    sprintf(buffer, "dczRelayIdx%d", relayID);
    domoticzSend(buffer, relayStatus(relayID) ? "1" : "0");
}

int relayFromIdx(unsigned int idx) {
    for (int relayID=0; relayID<relayCount(); relayID++) {
        if (relayToIdx(relayID) == idx) {
            return relayID;
        }
    }
    return -1;
}

int relayToIdx(unsigned int relayID) {
    char buffer[15];
    sprintf(buffer, "dczRelayIdx%d", relayID);
    return getSetting(buffer).toInt();
}

void relayDomoticzSetup() {

    mqttRegister([](unsigned int type, const char * topic, const char * payload) {

        String dczTopicOut = getSetting("dczTopicOut", DOMOTICZ_OUT_TOPIC);

        if (type == MQTT_CONNECT_EVENT) {
            mqttSubscribeRaw(dczTopicOut.c_str());
        }

        if (type == MQTT_MESSAGE_EVENT) {

            // Check topic
            if (dczTopicOut.equals(topic)) {

                // Parse response
                DynamicJsonBuffer jsonBuffer;
                JsonObject& root = jsonBuffer.parseObject((char *) payload);
                if (!root.success()) {
                    DEBUG_MSG("[DOMOTICZ] Error parsing data\n");
                    return;
                }

                // IDX
                unsigned long idx = root["idx"];
                int relayID = relayFromIdx(idx);
                if (relayID >= 0) {
                    unsigned long value = root["nvalue"];
                    DEBUG_MSG("[DOMOTICZ] Received value %d for IDX %d\n", value, idx);
                    relayStatus(relayID, value == 1);
                }

            }

        }

    });
}

#endif

//------------------------------------------------------------------------------
// MQTT
//------------------------------------------------------------------------------

void relayMQTT(unsigned char id) {
    if (id >= _relays.size()) return;
    String mqttGetter = getSetting("mqttGetter", MQTT_USE_GETTER);
    char buffer[strlen(MQTT_RELAY_TOPIC) + mqttGetter.length() + 3];
    sprintf(buffer, "%s/%d%s", MQTT_RELAY_TOPIC, id, mqttGetter.c_str());
    mqttSend(buffer, relayStatus(id) ? "1" : "0");
}

void relayMQTT() {
    for (unsigned int i=0; i < _relays.size(); i++) {
        relayMQTT(i);
    }
}

void relayMQTTCallback(unsigned int type, const char * topic, const char * payload) {

    String mqttSetter = getSetting("mqttSetter", MQTT_USE_SETTER);
    String mqttGetter = getSetting("mqttGetter", MQTT_USE_GETTER);
    bool sameSetGet = mqttGetter.compareTo(mqttSetter) == 0;

    if (type == MQTT_CONNECT_EVENT) {
        relayMQTT();
        char buffer[strlen(MQTT_RELAY_TOPIC) + mqttSetter.length() + 3];
        sprintf(buffer, "%s/+%s", MQTT_RELAY_TOPIC, mqttSetter.c_str());
        mqttSubscribe(buffer);
    }

    if (type == MQTT_MESSAGE_EVENT) {

        // Match topic
        String t = String(topic + mqttTopicRootLength());
        if (!t.startsWith(MQTT_RELAY_TOPIC)) return;
        if (!t.endsWith(mqttSetter)) return;

        // Get relay ID
        unsigned int relayID = topic[strlen(topic) - mqttSetter.length() - 1] - '0';
        if (relayID >= relayCount()) {
            DEBUG_MSG("[RELAY] Wrong relayID (%d)\n", relayID);
            return;
        }

        // Action to perform
        unsigned int value = (char)payload[0] - '0';
        if (value == 2) {
            relayToggle(relayID);
        } else {
            relayStatus(relayID, value > 0, !sameSetGet);
        }

    }

}

void relaySetupMQTT() {
    mqttRegister(relayMQTTCallback);
}

//------------------------------------------------------------------------------
// Setup
//------------------------------------------------------------------------------

void relaySetup() {

    #ifdef SONOFF_DUAL

        // Two dummy relays for the dual
        _relays.push_back((relay_t) {0, 0});
        _relays.push_back((relay_t) {0, 0});

    #else

        #ifdef RELAY1_PIN
            _relays.push_back((relay_t) { RELAY1_PIN, RELAY1_PIN_INVERSE });
        #endif
        #ifdef RELAY2_PIN
            _relays.push_back((relay_t) { RELAY2_PIN, RELAY2_PIN_INVERSE });
        #endif
        #ifdef RELAY3_PIN
            _relays.push_back((relay_t) { RELAY3_PIN, RELAY3_PIN_INVERSE });
        #endif
        #ifdef RELAY4_PIN
            _relays.push_back((relay_t) { RELAY4_PIN, RELAY4_PIN_INVERSE });
        #endif

    #endif

    EEPROM.begin(4096);
    byte relayMode = getSetting("relayMode", RELAY_MODE).toInt();

    for (unsigned int i=0; i < _relays.size(); i++) {
        pinMode(_relays[i].pin, OUTPUT);
        if (relayMode == RELAY_MODE_OFF) relayStatus(i, false);
        if (relayMode == RELAY_MODE_ON) relayStatus(i, true);
    }
    if (relayMode == RELAY_MODE_SAME) relayRetrieve();

    relaySetupAPI();
    relaySetupMQTT();
    #if ENABLE_DOMOTICZ
        relayDomoticzSetup();
    #endif

    DEBUG_MSG("[RELAY] Number of relays: %d\n", _relays.size());

}