/*
ESP8266 web server - platform-dependent routines, FreeRTOS version


Thanks to my collague at Espressif for writing the foundations of this code.
*/

#include "httpd.h"
#include "httpd-com.h"
#include "httpd-platform.h"

#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/queue.h"

#include "lwip/sockets.h"
#include "string.h"

static int httpPort;
static int httpMaxConnCt;

struct  RtosConnType {
    int fd;
    int needWriteDoneNotif;
    int needsClose;
    int port;
    char ip[4];
};

static RtosConnType rconn[HTTPD_MAX_CONNECTIONS];
static xQueueHandle queWebServerStop = NULL;

int  httpdPlatSendData(ConnTypePtr conn, char *buff, int len) {
    int ret = 0;
    char *cipher = buff;
    unsigned short clen = len;
    conn->needWriteDoneNotif = 1;
    if (!cipher || clen == 0)
        return false;
    ret = write(conn->fd, cipher, clen);
    cipher != buff ? free(cipher) : 0;
    return ret >= 0;
}

void  httpdPlatDisconnect(ConnTypePtr conn) {
    conn->needsClose = 1;
    conn->needWriteDoneNotif = 1; //because the real close is done in the writable select code
}

void httpdPlatDisableTimeout(ConnTypePtr conn) {
    //Unimplemented for FreeRTOS
}


#define RECV_BUF_SIZE 1460
static void platHttpServerTask(void *pvParameters) {
    int32_t listenfd;
    int32_t remotefd;
    int32_t len;
    int32_t ret;
    int x;
    int maxfdp = 0;
    fd_set readset, writeset;
    struct sockaddr name;
    struct timeval timeout;
    struct sockaddr_in server_addr;
    struct sockaddr_in remote_addr;
    
    portBASE_TYPE xStatus;    
    bool ValueFromReceive = false;
    for (x = 0; x < HTTPD_MAX_CONNECTIONS; x++) {
        rconn[x].fd = -1;
    }

    /* Construct local address structure */
    memset(&server_addr, 0, sizeof(server_addr)); /* Zero out structure */
    server_addr.sin_family = AF_INET;           /* Internet address family */
    server_addr.sin_addr.s_addr = INADDR_ANY;   /* Any incoming interface */
    server_addr.sin_len = sizeof(server_addr);
    server_addr.sin_port = htons(httpPort); /* Local port */
    
    /* Create socket for incoming connections */
    do {
        listenfd = socket(AF_INET, SOCK_STREAM, 0);
        if (listenfd == -1) {
            httpd_printf("platHttpServerTask: failed to create sock!\n");
            vTaskDelay(1000 / portTICK_RATE_MS);
        }
    } while (listenfd == -1);
    /* Bind to the local port */
    do {
        ret = bind(listenfd, (struct sockaddr *)&server_addr, sizeof(server_addr));
        if (ret != 0) {
            httpd_printf("platHttpServerTask: failed to bind!\n");
            vTaskDelay(1000 / portTICK_RATE_MS);
        }
    } while (ret != 0);
    do {
        /* Listen to the local connection */
        ret = listen(listenfd, HTTPD_MAX_CONNECTIONS);
        if (ret != 0) {
            httpd_printf("platHttpServerTask: failed to listen!\n");
            vTaskDelay(1000 / portTICK_RATE_MS);
        }

    } while (ret != 0);

//    httpd_printf("esphttpd: active and listening to connections.\n");
    while (1) {
        // clear fdset, and set the select function wait time
        int socketsFull = 1;
        maxfdp = 0;
        FD_ZERO(&readset);
        FD_ZERO(&writeset);
        timeout.tv_sec = 2;
        timeout.tv_usec = 0;

        for (x = 0; x < HTTPD_MAX_CONNECTIONS; x++) {
            if (rconn[x].fd != -1) {
                FD_SET(rconn[x].fd, &readset);
                if (rconn[x].needWriteDoneNotif) FD_SET(rconn[x].fd, &writeset);
                if (rconn[x].fd > maxfdp) maxfdp = rconn[x].fd;
            } else {
                socketsFull = 0;
            }
        }

        if (!socketsFull) {
            FD_SET(listenfd, &readset);
            if (listenfd > maxfdp) maxfdp = listenfd;
        }
        xStatus = xQueueReceive(queWebServerStop, &ValueFromReceive, 0);
        if ( pdPASS == xStatus && true == ValueFromReceive) {
            httpd_printf("user_webserver_task rcv exit signal!\r\n");
            break;
        }

        //polling all exist client handle,wait until readable/writable
        ret = select(maxfdp + 1, &readset, &writeset, NULL, &timeout); //&timeout
        if (ret > 0) {
            //See if we need to accept a new connection
            if (FD_ISSET(listenfd, &readset)) {
                len = sizeof(struct sockaddr_in);
                remotefd = accept(listenfd, (struct sockaddr *)&remote_addr, (socklen_t *)&len);
                if (remotefd < 0) {
                   httpd_printf("platHttpServerTask: Huh? Accept failed.\n");
                    continue;
                }
                for (x = 0; x < HTTPD_MAX_CONNECTIONS; x++) if (rconn[x].fd == -1) break;
                if (x == HTTPD_MAX_CONNECTIONS) {
                    httpd_printf("platHttpServerTask: Huh? Got accept with all slots full.\n");
                    continue;
                }
                int keepAlive = 1; //enable keepalive
                int keepIdle = 60; //60s
                int keepInterval = 5; //5s
                int keepCount = 3; //retry times

                setsockopt(remotefd, SOL_SOCKET, SO_KEEPALIVE, (void *)&keepAlive, sizeof(keepAlive));
                setsockopt(remotefd, IPPROTO_TCP, TCP_KEEPIDLE, (void*)&keepIdle, sizeof(keepIdle));
                setsockopt(remotefd, IPPROTO_TCP, TCP_KEEPINTVL, (void *)&keepInterval, sizeof(keepInterval));
                setsockopt(remotefd, IPPROTO_TCP, TCP_KEEPCNT, (void *)&keepCount, sizeof(keepCount));

                rconn[x].fd = remotefd;
                rconn[x].needWriteDoneNotif = 0;
                rconn[x].needsClose = 0;

                len = sizeof(name);
                getpeername(remotefd, &name, (socklen_t *)&len);
                struct sockaddr_in *piname = (struct sockaddr_in *)&name;

                rconn[x].port = piname->sin_port;
                memcpy(&rconn[x].ip, &piname->sin_addr.s_addr, sizeof(rconn[x].ip));

                httpdConnectCb(&rconn[x], rconn[x].ip, rconn[x].port);
                //ets_timer_disarm(&connData[x].conn->stop_watch);
                //ets_timer_setfn(&connData[x].conn->stop_watch, (ETSTimerFunc *)httpserver_conn_watcher, connData[x].conn);
                //ets_timer_arm(&connData[x].conn->stop_watch, STOP_TIMER, 0);
            }

            //See if anything happened on the existing connections.
            for (x = 0; x < HTTPD_MAX_CONNECTIONS; x++) {
                //Skip empty slots
                if (rconn[x].fd == -1) continue;

                //Check for write availability first: the read routines may write needWriteDoneNotif while
                //the select didn't check for that.
                if (rconn[x].needWriteDoneNotif && FD_ISSET(rconn[x].fd, &writeset)) {
                    rconn[x].needWriteDoneNotif = 0; //Do this first, httpdSentCb may write something making this 1 again.
                    if (rconn[x].needsClose) {
                        //Do callback and close fd.
                        
                        httpdDisconCb(&rconn[x], rconn[x].ip, rconn[x].port);
                        close(rconn[x].fd);
                        rconn[x].fd = -1;
                    } else {
                        httpdSentCb(&rconn[x], rconn[x].ip, rconn[x].port);
                    }
                }

                if (FD_ISSET(rconn[x].fd, &readset)) {
                    char *precvbuf = (char*)malloc(RECV_BUF_SIZE + 1);
                    if (precvbuf==NULL) httpd_printf("platHttpServerTask: memory exhausted!\n");
                    memset(precvbuf, 0, RECV_BUF_SIZE + 1);
                    ret = recv(rconn[x].fd, precvbuf, RECV_BUF_SIZE, 0);
                    if (ret > 0) {
                        //Data received. Pass to httpd.
                        char *plain = NULL;
                        unsigned short plen = strlen(precvbuf);
                        if (precvbuf && plen > 0)
                            httpdRecvCb(&rconn[x], rconn[x].ip, rconn[x].port, precvbuf, plen);
                    } 
//                    else
                    {
                        //recv error,connection close
                        httpdDisconCb(&rconn[x], rconn[x].ip, rconn[x].port);
                        close(rconn[x].fd);
                        rconn[x].fd = -1;
                    }
                    if (precvbuf) free(precvbuf);
                }
            }
        }
    }  
    close(listenfd);
    vTaskDelete(NULL);
}

int  httpdPlatUninit(void) 
{
    bool ValueToSend = true;
    portBASE_TYPE xStatus;
    
    configASSERT(queWebServerStop);
    if (queWebServerStop == NULL) {
        return -1;
    }
    xStatus = xQueueSend(queWebServerStop, &ValueToSend, 0);
    if (xStatus != pdPASS) {
        httpd_printf("Web server can not send to the queue!\r\n");
        return -1;
    } else {
        httpd_printf("queWebServerStop send ok\r\n");
        return pdPASS;
    }
}


//Initialize listening socket, do general initialization
void  httpdPlatInit(int port, int maxConnCt) {
    httpPort = port;
    httpMaxConnCt = maxConnCt;
    if (queWebServerStop == NULL)
        queWebServerStop = xQueueCreate(1, 1);
    configASSERT(queWebServerStop);
    httpd_printf ("user_webserver_task start\r\n");
    
    xTaskCreate(platHttpServerTask, "esphttpd", HTTPD_STACKSIZE, NULL, WEB_SERVER_TASK_PRIO, NULL);
}