#include <cmdHandler.h>

#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>

#include <socket.h>

#include <logger.h>
#include <PontCoopScheduler.h>
#include <wizHelper.h>
#include <mbusComm.h>


extern const uint8_t CMD_SOCK;

const uint16_t cmdPort = 23;

typedef enum {
    CH_INIT,
    CH_LISTEN,
    CH_WAITING,
    CH_BANNER,
    CH_PROMPT,
    CH_RECEIVE,
    CH_DISCONNECT,
    CH_DISCONNECT_WAIT,
    CH_ERROR
} chState_t;


// clear statistics
bool clearCmd() {
    t_mbusCommStats zeroedStats = { .requestCnt = 0, .errorCnt = 0 };
    mbusCommSetStats(zeroedStats);
    return true;
}

// returns 0 to continue waiting for input
// returns -1 to close the connection
// returns 1 to toggle to config mode
// returns 2 to toggle back to default mode
int8_t cmdExecuteCommand(uint8_t *cmd, bool resetConfigMode) {
    const static uint8_t HELP_MSG[] = \
      "Usage\n\r" \
      "\n\r" \
      "help ................................. Show this help page\n\r" \
      "quit ................................. Terminate the console session\n\r" \
      "enable ............................... Enable configuration mode\n\r" \
      "disable .............................. Disable configuration mode\n\r" \
      "clear ................................ Clears the global Meterbus\n\r" \
      "                                       statistics\n\r" \
      "                                       Required configuration mode\n\r" \
      ;
    const static uint8_t GOODBYE_MSG[] = "Good bye\n\r";
    const static uint8_t OK_MSG[] = "OK\n\r";
    const static uint8_t FAILED_MSG[] = "Failed\n\r";
    const static uint8_t REQUIRES_CONFIG_MODE_MGS[] = "Not executed, requires config mode\n\r";
    uint8_t *messageToSend = NULL;

    static bool configMode = false;

    if (resetConfigMode) {
        configMode = false;
    }

    int8_t retCode = 0;
    coloredMsg(LOG_YELLOW, "cec, cmd is %s", cmd);
    if (0 == strcmp(cmd, "quit")) {
        messageToSend = GOODBYE_MSG;
        retCode = -1;
    } else if (0 == strcmp(cmd, "help")) {
        messageToSend = HELP_MSG;
        retCode = -1;
    } else if (0 == strcmp(cmd, "enable")) {
        coloredMsg(LOG_YELLOW, "cec, enable config mode");
        configMode = true;
        retCode = 1;
    } else if (0 == strcmp(cmd, "disable")) {
        coloredMsg(LOG_YELLOW, "cec, disable config mode");
        configMode = false;
        retCode = 2;
    } else if (0 == strcmp(cmd, "clear")) {
        if (configMode) {
            messageToSend = clearCmd() ? OK_MSG : FAILED_MSG;
        } else {
            messageToSend = REQUIRES_CONFIG_MODE_MGS;
        }
    }

    if (messageToSend) {
        send(CMD_SOCK, messageToSend, strlen(messageToSend));
    }

    return retCode;
}

void cmdHandlerEngine(void *handle) {
    static uint8_t receiveBuffer[256];

    static chState_t state = CH_INIT;
    static bool resetConfigMode = false;

    static uint8_t banner[] = \
      "MBGW3\n\r" \
      "Type help for usage help\n\r" \
      "or quit to close the connection.\n\r";

    static uint8_t *prompt;
    static uint8_t defaultPrompt[] = "MBGW3 # ";
    static uint8_t elevatedPrompt[] = "MBGW3 (admin) > ";


    int8_t res = 0;
    uint8_t sockState;
    int32_t resultSend;
    int16_t receivedOctets;
    int32_t resultRecv;
    uint8_t resultDisconnect;


    if (isNetworkAvailable()) {
        switch (state) {
        case CH_INIT:
            coloredMsg(LOG_YELLOW, "che, initializing socket");

            res = socket(CMD_SOCK, Sn_MR_TCP, cmdPort, SF_IO_NONBLOCK);
            coloredMsg(LOG_YELLOW, "che, socket returns %d", res);

            if (res == CMD_SOCK) {
                coloredMsg(LOG_YELLOW, "che, socket is initialized");
                state = CH_LISTEN;
            } else {
                state = CH_ERROR;
            }
            break;

        case CH_LISTEN:
            coloredMsg(LOG_YELLOW, "che, listening");
            
            res = listen(CMD_SOCK);
            coloredMsg(LOG_YELLOW, "che, listen returns %d", res);

            if (res == SOCK_OK) {
                coloredMsg(LOG_YELLOW, "che, ok, waiting for established");
                state = CH_WAITING;
            } else {
                state = CH_ERROR;
            }
            break;

        case CH_WAITING:
            //coloredMsg(LOG_YELLOW, "che, waiting for established");

            sockState = getSn_SR(CMD_SOCK);
            if (sockState != SOCK_LISTEN) {
                coloredMsg(LOG_YELLOW, "che, socket state is 0x%02x", sockState);
            }

            if (sockState == SOCK_ESTABLISHED) {
                coloredMsg(LOG_YELLOW, "che, connection is established");
                state = CH_BANNER;
            }
            break;

        case CH_BANNER:
            coloredMsg(LOG_YELLOW, "che, send banner");
            sockState = getSn_SR(CMD_SOCK);
            if (sockState != SOCK_ESTABLISHED) {
                coloredMsg(LOG_YELLOW, "che sockState is 0x%02x when trying to send banner", sockState);
                state = CH_DISCONNECT;
            } else {
                resultSend = send(CMD_SOCK, banner, strlen(banner));
                coloredMsg(LOG_YELLOW, "che, sent banner, send returns 0x%02x", resultSend);
                prompt = defaultPrompt;
                resetConfigMode = true;
                state = CH_PROMPT;
            }
            break;

        case CH_PROMPT:
            coloredMsg(LOG_YELLOW, "che send prompt");
            sockState = getSn_SR(CMD_SOCK);
            if (sockState != SOCK_ESTABLISHED) {
                coloredMsg(LOG_YELLOW, "che sockState is 0x%02x when trying to send promt", sockState);
                state = CH_DISCONNECT;
            } else {
                resultSend = send(CMD_SOCK, prompt, strlen(prompt));
                coloredMsg(LOG_YELLOW, "che, sent prompt %s, send returns 0x%02x", prompt, resultSend);
                state = CH_RECEIVE;
            }
            break;

        case CH_RECEIVE:
            sockState = getSn_SR(CMD_SOCK);
            if (sockState != SOCK_ESTABLISHED) {
                coloredMsg(LOG_YELLOW, "che sockState is 0x%02x when trying to receive something", sockState);
                state = CH_DISCONNECT;
            } else {
                // coloredMsg(LOG_YELLOW, "che, now waiting for some input");
                receivedOctets = getSn_RX_RSR(CMD_SOCK);
                // coloredMsg(LOG_YELLOW, "che, getSn_RxMAX returns %d", res16);

                if (receivedOctets > 0) {
                    memset(receiveBuffer, 0, sizeof(receiveBuffer));
                    resultRecv = recv(CMD_SOCK, receiveBuffer, sizeof(receiveBuffer));
                    coloredMsg(LOG_YELLOW, "che, recv returns 0x%02x", resultRecv);
                    if (resultRecv > 0) {
                        if ((receiveBuffer[strlen(receiveBuffer) - 1] == 0x0a) ||
                            (receiveBuffer[strlen(receiveBuffer) - 1] == 0x0d)) {
                            receiveBuffer[strlen(receiveBuffer) - 1] = 0;
                        }
                        if ((receiveBuffer[strlen(receiveBuffer) - 1] == 0x0a) ||
                            (receiveBuffer[strlen(receiveBuffer) - 1] == 0x0d)) {
                            receiveBuffer[strlen(receiveBuffer) - 1] = 0;
                        }
                        coloredMsg(LOG_YELLOW, "che, received: %s", receiveBuffer);
                        int8_t resCEC = cmdExecuteCommand(receiveBuffer, resetConfigMode);
                        resetConfigMode = false;
                        switch (resCEC) {
                            case 0:
                                state = CH_PROMPT;
                                break;
                            case -1:
                                state = CH_DISCONNECT;
                                break;
                            case 1:
                                prompt = elevatedPrompt;
                                state = CH_PROMPT;
                                break;
                            case 2:
                                prompt = defaultPrompt;
                                state = CH_PROMPT;
                                break;
                        }
                    }
                }
            }
            break;

        case CH_DISCONNECT:
            coloredMsg(LOG_YELLOW, "che, close our end");
            resultDisconnect = disconnect(CMD_SOCK);
            coloredMsg(LOG_YELLOW, "che, disconnect returns 0x%02x", resultDisconnect);
            state = CH_DISCONNECT_WAIT;
            break;

        case CH_DISCONNECT_WAIT:
            coloredMsg(LOG_YELLOW, "che, waiting after disconnect");
            sockState = getSn_SR(CMD_SOCK);
            coloredMsg(LOG_YELLOW, "che, sockState is 0x%02x", sockState);
            if (sockState == SOCK_CLOSED) {
                coloredMsg(LOG_YELLOW, "che, socket is closed now");
                state = CH_INIT;
            }
            break;
        

        case CH_ERROR:
            coloredMsg(LOG_YELLOW, "che, error state, will stop here");
            schDel(cmdHandlerEngine, NULL);
            break;
        }
    }
}

void cmdHandlerInit() {
    schAdd(cmdHandlerEngine, NULL, 0, 100);
}