#include <sys/random.h>
#include "websock.h"

#define SAT_WEBSOCK_HANDSHAKE_UNIQUE "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
#define SAT_WEBSOCK_HANDSHAKE_VERSION_10 "HTTP/1.0 "
#define SAT_WEBSOCK_HANDSHAKE_VERSION_11 "HTTP/1.1 "
#define SAT_WEBSOCK_HANDSHAKE_LINE_END (0x0D0A)

sat_websock_handshake_ptr sat_websock_handshake_alloc(void) {
    sat_websock_handshake_ptr hs = malloc(sizeof(sat_websock_handshake));
    memset(hs, 0, sizeof(sat_websock_handshake));
    return hs;
}

void sat_websock_handshake_free(sat_websock_handshake_ptr hs, bool freeArg) {
    if(hs == NULL) return;

    if(freeArg) free(hs);
}

int sat_websock_handshake_gen_key(sat_websock_handshake_ptr hs) {
    return getrandom(hs->key, 16, 0);
}

int sat_websock_handshake_send(sat_websock_handshake_ptr hs) {
    char buffer[1024] = {0};
    size_t count = 0;

    count += sprintf(buffer + count, "GET %s HTTP/1.1\r\n", hs->path);
    count += sprintf(buffer + count, "Host: %s\r\n", hs->host);
    count += sprintf(buffer + count, "Upgrade: websocket\r\n");
    count += sprintf(buffer + count, "Connection: Upgrade\r\n");
    count += sprintf(buffer + count, "Sec-WebSocket-Version: 13\r\n");
    count += sprintf(buffer + count, "Sec-WebSocket-Key: %s\r\n", hs->key);
    if(hs->origin != NULL)   count += sprintf(buffer + count, "Origin: %s\r\n", hs->origin);
    if(hs->protocol != NULL) count += sprintf(buffer + count, "Sec-WebSocket-Protocol: %s\r\n", hs->protocol);
    count += sprintf(buffer + count, "\r\n");

    return sat_websock_send(hs->websock, (uint8_t*)buffer, count);
}

int sat_websock_handshake_recv(sat_websock_handshake_ptr hs) {
    char buffer[1024] = {0};

    sat_websock_buffer(hs->websock, 100);

    int expect = strlen(SAT_WEBSOCK_HANDSHAKE_VERSION_11);
    int read = sat_websock_recv(hs->websock, (uint8_t*)buffer, expect);
    if(read != expect) return -1;
    if(strcmp(SAT_WEBSOCK_HANDSHAKE_VERSION_11, buffer) != 0
        && strcmp(SAT_WEBSOCK_HANDSHAKE_VERSION_10, buffer) != 0)
        return -2;

    uint16_t checkCrLf = 0;

    int i;
    for(i = 0; i < sizeof buffer && checkCrLf != SAT_WEBSOCK_HANDSHAKE_LINE_END; ++i) {
        buffer[i] = sat_buffer_getc(hs->websock->buffer);
        checkCrLf <<= 8;
        checkCrLf |= buffer[i];
    }
    buffer[i] = '\0';

    if(sscanf(buffer, "%hd %s", &hs->statusCode, hs->statusReason) != 2)
        return -3;

    hs->completed = true;
    hs->upgraded = hs->statusCode == 101;

    return 0;
}