/*
  +----------------------------------------------------------------------+
  | Swoole                                                               |
  +----------------------------------------------------------------------+
  | This source file is subject to version 2.0 of the Apache license,    |
  | that is bundled with this package in the file LICENSE, and is        |
  | available through the world-wide-web at the following url:           |
  | http://www.apache.org/licenses/LICENSE-2.0.html                      |
  | If you did not receive a copy of the Apache2.0 license and are unable|
  | to obtain it through the world-wide-web, please send a note to       |
  | license@swoole.com so we can mail you a copy immediately.            |
  +----------------------------------------------------------------------+
  | Author: Tianfeng Han  <rango@swoole.com>                             |
  |         Twosee  <twose@qq.com>                                       |
  +----------------------------------------------------------------------+
*/

#pragma once

#include <sys/socket.h>
#include <sys/un.h>
#include <sys/uio.h>
#include <netinet/in.h>
#if defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__)
#include <sys/types.h>
#endif
#include <netinet/ip6.h>
#include <netinet/tcp.h>
#include <netinet/udp.h>
#include <arpa/inet.h>

#include <string>
#include <vector>

#include "swoole.h"
#include "swoole_ssl.h"
#include "swoole_buffer.h"
#include "swoole_file.h"

#ifndef SOCK_NONBLOCK
#define SOCK_NONBLOCK O_NONBLOCK
#endif

#ifdef __sun
#define s6_addr8 _S6_un._S6_u8
#define s6_addr16 _S6_un._S6_u16
#define s6_addr32 _S6_un._S6_u32
#endif

static bool IN_IS_ADDR_LOOPBACK(struct in_addr *a) {
    return a->s_addr == htonl(INADDR_LOOPBACK);
}

// OS Feature
#if defined(HAVE_KQUEUE) || !defined(HAVE_SENDFILE)
ssize_t swoole_sendfile(int out_fd, int in_fd, off_t *offset, size_t size);
#else
#include <sys/sendfile.h>
#define swoole_sendfile(out_fd, in_fd, offset, limit) sendfile(out_fd, in_fd, offset, limit)
#endif

enum {
    SW_BAD_SOCKET = -1,
};

namespace swoole {
struct GetaddrinfoRequest;

namespace network {

struct SendfileTask {
    off_t offset;
    size_t length;
    char filename[0];
};

struct SendfileRequest {
    File file;
    size_t length;
    off_t offset;

  public:
    SendfileRequest(const char *filename, off_t _offset, size_t _length) : file(filename, O_RDONLY) {
        offset = _offset;
        length = _length;
    }
};

struct Address {
    union {
        struct sockaddr ss;
        struct sockaddr_in inet_v4;
        struct sockaddr_in6 inet_v6;
        struct sockaddr_un un;
    } addr;
    socklen_t len;
    SocketType type;

    bool assign(SocketType _type, const std::string &_host, int _port);
    bool assign(const std::string &url);

    const char *get_ip() {
        return get_addr();
    }

    int get_port();
    const char *get_addr();

    bool is_loopback_addr() {
        if (type == SW_SOCK_TCP || type == SW_SOCK_UDP) {
            return IN_IS_ADDR_LOOPBACK(&addr.inet_v4.sin_addr);
        } else if (type == SW_SOCK_TCP6 || type == SW_SOCK_UDP6) {
            return IN6_IS_ADDR_LOOPBACK(&addr.inet_v6.sin6_addr);
        }
        return false;
    }

    static bool verify_ip(int __af, const std::string &str) {
        char tmp_address[INET6_ADDRSTRLEN];
        return inet_pton(__af, str.c_str(), tmp_address) != -1;
    }
};

struct IOVector {
    // we should modify iov_iterator instead of iov, iov is readonly
    struct iovec *iov = nullptr;
    struct iovec *iov_iterator = nullptr;
    int count = 0;
    int remain_count = 0;
    int index = 0;
    size_t offset_bytes = 0;

    IOVector(struct iovec *_iov, int _iovcnt);
    ~IOVector();

    void update_iterator(ssize_t __n);

    struct iovec *get_iterator() {
        return iov_iterator;
    }

    size_t length() {
        size_t len = 0;
        SW_LOOP_N(count) {
            len += iov[i].iov_len;
        }
        return len;
    }

    int get_remain_count() {
        return remain_count;
    }

    int get_index() {
        return index;
    }

    size_t get_offset_bytes() {
        return offset_bytes;
    }
};

struct Socket {
    static double default_dns_timeout;
    static double default_connect_timeout;
    static double default_read_timeout;
    static double default_write_timeout;
    static uint32_t default_buffer_size;

    int fd;
    FdType fd_type;
    SocketType socket_type;
    int events;
    bool enable_tcp_nodelay;

    uchar removed : 1;
    uchar silent_remove : 1;
    uchar nonblock : 1;
    uchar cloexec : 1;
    uchar direct_send : 1;
#ifdef SW_USE_OPENSSL
    uchar ssl_send_ : 1;
    uchar ssl_want_read : 1;
    uchar ssl_want_write : 1;
    uchar ssl_renegotiation : 1;
    uchar ssl_handshake_buffer_set : 1;
    uchar ssl_quiet_shutdown : 1;
    uchar ssl_closed_ : 1;
#ifdef SW_SUPPORT_DTLS
    uchar dtls : 1;
#endif
#endif
    uchar dontwait : 1;
    uchar close_wait : 1;
    uchar send_wait : 1;
    uchar tcp_nopush : 1;
    uchar tcp_nodelay : 1;
    uchar skip_recv : 1;
    uchar recv_wait : 1;
    uchar event_hup : 1;
    uchar dont_restart : 1;

    // memory buffer size [user space]
    uint32_t buffer_size;
    uint32_t chunk_size;

    void *object;

#ifdef SW_USE_OPENSSL
    SSL *ssl;
    uint32_t ssl_state;
#endif

    Address info;
    double recv_timeout_ = default_read_timeout;
    double send_timeout_ = default_write_timeout;

    double last_received_time;
    double last_sent_time;

    Buffer *out_buffer;
    Buffer *in_buffer;
    String *recv_buffer;

    TimerNode *recv_timer;
    TimerNode *send_timer;

    size_t total_recv_bytes;
    size_t total_send_bytes;

    // for reactor
    int handle_send();
    int handle_sendfile();
    // user space memory buffer
    void set_memory_buffer_size(uint32_t _buffer_size) {
        buffer_size = _buffer_size;
    }
    // socket option [kernel buffer]
    bool set_buffer_size(uint32_t _buffer_size);
    bool set_recv_buffer_size(uint32_t _buffer_size);
    bool set_send_buffer_size(uint32_t _buffer_size);
    bool set_timeout(double timeout);
    bool set_recv_timeout(double timeout);
    bool set_send_timeout(double timeout);

    bool set_nonblock() {
        return set_fd_option(1, -1);
    }

    bool set_block() {
        return set_fd_option(0, -1);
    }

    bool set_fd_option(int _nonblock, int _cloexec);

    int set_option(int level, int optname, int optval) {
        return setsockopt(fd, level, optname, &optval, sizeof(optval));
    }

    int set_option(int level, int optname, const void *optval, socklen_t optlen) {
        return setsockopt(fd, level, optname, optval, optlen);
    }

    int get_option(int level, int optname, void *optval, socklen_t *optlen) {
        return getsockopt(fd, level, optname, optval, optlen);
    }

    int get_option(int level, int optname, int *optval) {
        socklen_t optlen = sizeof(*optval);
        return get_option(level, optname, optval, &optlen);
    }

    int get_fd() {
        return fd;
    }

    int move_fd() {
        int sock_fd = fd;
        fd = SW_BAD_SOCKET;
        return sock_fd;
    }

    int get_name(Address *sa) {
        sa->len = sizeof(sa->addr);
        return getsockname(fd, &sa->addr.ss, &sa->len);
    }

    int set_tcp_nopush(int nopush) {
#ifdef TCP_CORK
        if (set_option(IPPROTO_TCP, TCP_CORK, nopush) == SW_ERR) {
            return -1;
        } else {
            tcp_nopush = nopush;
            return 0;
        }
#else
        return -1;
#endif
    }

    int set_reuse_addr(int enable = 1) {
        return set_option(SOL_SOCKET, SO_REUSEADDR, enable);
    }

    int set_reuse_port(int enable = 1) {
#ifdef SO_REUSEPORT
        return set_option(SOL_SOCKET, SO_REUSEPORT, enable);
#endif
        return -1;
    }

    int set_tcp_nodelay(int nodelay = 1) {
        if (set_option(IPPROTO_TCP, TCP_NODELAY, nodelay) == SW_ERR) {
            return -1;
        } else {
            tcp_nodelay = nodelay;
            return 0;
        }
    }

    bool check_liveness() {
        char buf;
        errno = 0;
        ssize_t retval = peek(&buf, sizeof(buf), MSG_DONTWAIT);
        return !(retval == 0 || (retval < 0 && catch_read_error(errno) == SW_CLOSE));
    }

    /**
     * socket io operation
     */
    int sendfile(const char *filename, off_t offset, size_t length);
    ssize_t recv(void *__buf, size_t __n, int __flags);
    ssize_t send(const void *__buf, size_t __n, int __flags);
    ssize_t peek(void *__buf, size_t __n, int __flags);
    Socket *accept();
    int bind(const std::string &_host, int *port);
    Socket *dup();

    ssize_t readv(IOVector *io_vector);
    ssize_t writev(IOVector *io_vector);

    ssize_t writev(const struct iovec *iov, size_t iovcnt) {
        return ::writev(fd, iov, iovcnt);
    }

    int bind(const Address &sa) {
        return ::bind(fd, &sa.addr.ss, sizeof(sa.addr.ss));
    }

    int listen(int backlog = 0) {
        return ::listen(fd, backlog <= 0 ? SW_BACKLOG : backlog);
    }

    void clean();
    ssize_t send_blocking(const void *__data, size_t __len);
    ssize_t send_async(const void *__data, size_t __len);
    ssize_t recv_blocking(void *__data, size_t __len, int flags);
    int sendfile_blocking(const char *filename, off_t offset, size_t length, double timeout);
    ssize_t writev_blocking(const struct iovec *iov, size_t iovcnt);

    int connect(const Address &sa) {
        return ::connect(fd, &sa.addr.ss, sa.len);
    }

    int connect(const Address *sa) {
        return ::connect(fd, &sa->addr.ss, sa->len);
    }

    int connect(const std::string &host, int port) {
        Address addr;
        addr.assign(socket_type, host, port);
        return connect(addr);
    }

#ifdef SW_USE_OPENSSL
    void ssl_clear_error() {
        ERR_clear_error();
        ssl_want_read = 0;
        ssl_want_write = 0;
    }
    int ssl_create(SSLContext *_ssl_context, int _flags);
    int ssl_connect();
    ReturnCode ssl_accept();
    ssize_t ssl_recv(void *__buf, size_t __n);
    ssize_t ssl_send(const void *__buf, size_t __n);
    ssize_t ssl_readv(IOVector *io_vector);
    ssize_t ssl_writev(IOVector *io_vector);
    ssize_t ssl_sendfile(const File &fp, off_t *offset, size_t size);
    STACK_OF(X509) * ssl_get_peer_cert_chain();
    std::vector<std::string> ssl_get_peer_cert_chain(int limit);
    X509 *ssl_get_peer_certificate();
    int ssl_get_peer_certificate(char *buf, size_t n);
    bool ssl_get_peer_certificate(String *buf);
    bool ssl_verify(bool allow_self_signed);
    bool ssl_check_host(const char *tls_host_name);
    void ssl_catch_error();
    bool ssl_shutdown();
    void ssl_close();
    const char *ssl_get_error_reason(int *reason);
#endif

    ssize_t recvfrom(char *__buf, size_t __len, int flags, Address *sa) {
        sa->len = sizeof(sa->addr);
        return ::recvfrom(fd, __buf, __len, flags, &sa->addr.ss, &sa->len);
    }

    bool cork() {
        if (tcp_nopush) {
            return false;
        }
#ifdef TCP_CORK
        if (set_tcp_nopush(1) < 0) {
            swoole_sys_warning("set_tcp_nopush(fd=%d, ON) failed", fd);
            return false;
        }
#endif
        // Need to turn off tcp nodelay when using nopush
        if (tcp_nodelay && set_tcp_nodelay(0) != 0) {
            swoole_sys_warning("set_tcp_nodelay(fd=%d, OFF) failed", fd);
        }
        return true;
    }

    bool uncork() {
        if (!tcp_nopush) {
            return false;
        }
#ifdef TCP_CORK
        if (set_tcp_nopush(0) < 0) {
            swoole_sys_warning("set_tcp_nopush(fd=%d, OFF) failed", fd);
            return false;
        }
#endif
        // Restore tcp_nodelay setting
        if (enable_tcp_nodelay && tcp_nodelay == 0 && set_tcp_nodelay(1) != 0) {
            swoole_sys_warning("set_tcp_nodelay(fd=%d, ON) failed", fd);
            return false;
        }
        return true;
    }

    bool isset_readable_event() {
        return events & SW_EVENT_READ;
    }

    bool isset_writable_event() {
        return events & SW_EVENT_WRITE;
    }

    int wait_event(int timeout_ms, int events);
    void free();

    static inline int is_dgram(SocketType type) {
        return (type == SW_SOCK_UDP || type == SW_SOCK_UDP6 || type == SW_SOCK_UNIX_DGRAM);
    }

    static inline int is_stream(SocketType type) {
        return (type == SW_SOCK_TCP || type == SW_SOCK_TCP6 || type == SW_SOCK_UNIX_STREAM);
    }

    bool is_stream() {
        return socket_type == SW_SOCK_TCP || socket_type == SW_SOCK_TCP6 || socket_type == SW_SOCK_UNIX_STREAM;
    }

    bool is_dgram() {
        return socket_type == SW_SOCK_UDP || socket_type == SW_SOCK_UDP6 || socket_type == SW_SOCK_UNIX_DGRAM;
    }

    bool is_inet4() {
        return socket_type == SW_SOCK_TCP || socket_type == SW_SOCK_UDP;
    }

    bool is_inet6() {
        return socket_type == SW_SOCK_TCP6 || socket_type == SW_SOCK_UDP6;
    }

    bool is_inet() {
        return is_inet4() || is_inet6();
    }

    bool is_local() {
        return socket_type == SW_SOCK_UNIX_STREAM || socket_type == SW_SOCK_UNIX_DGRAM;
    }

    ssize_t write(const void *__buf, size_t __len) {
        return ::write(fd, __buf, __len);
    }

    ssize_t read(void *__buf, size_t __len) {
        return ::read(fd, __buf, __len);
    }

    /**
     * Read data from the socket synchronously without setting non-blocking or blocking IO,
     * and allow interruptions by signals.
     */
    ssize_t read_sync(void *__buf, size_t __len, int timeout_ms = -1);

    /**
     * Write data to the socket synchronously without setting non-blocking or blocking IO,
     * and allow interruptions by signals.
     */
    ssize_t write_sync(const void *__buf, size_t __len, int timeout_ms = -1);

    int shutdown(int __how) {
        return ::shutdown(fd, __how);
    }

    ssize_t sendto_blocking(const Address &dst_addr, const void *__buf, size_t __n, int flags = 0);
    ssize_t recvfrom_blocking(char *__buf, size_t __len, int flags, Address *sa);

    ssize_t sendto(const char *dst_host, int dst_port, const void *data, size_t len, int flags = 0) const {
        Address addr = {};
        if (!addr.assign(socket_type, dst_host, dst_port)) {
            return SW_ERR;
        }
        return sendto(addr, data, len, flags);
    }

    ssize_t sendto(const Address &dst_addr, const void *data, size_t len, int flags) const {
        return ::sendto(fd, data, len, flags, &dst_addr.addr.ss, dst_addr.len);
    }

    int catch_error(int err) const {
        switch (err) {
        case EFAULT:
            abort();
            return SW_ERROR;
        case EBADF:
        case ENOENT:
            return SW_INVALID;
        case ECONNRESET:
        case ECONNABORTED:
        case EPIPE:
        case ENOTCONN:
        case ETIMEDOUT:
        case ECONNREFUSED:
        case ENETDOWN:
        case ENETUNREACH:
        case EHOSTDOWN:
        case EHOSTUNREACH:
        case SW_ERROR_SSL_BAD_CLIENT:
        case SW_ERROR_SSL_RESET:
            return SW_CLOSE;
        case EAGAIN:
#if EAGAIN != EWOULDBLOCK
        case EWOULDBLOCK:
#endif
#ifdef HAVE_KQUEUE
        case ENOBUFS:
#endif
        case 0:
            return SW_WAIT;
        default:
            return SW_ERROR;
        }
    }

    int catch_write_error(int err) const {
        switch (err) {
        case ENOBUFS:
            return SW_WAIT;
        default:
            return catch_error(err);
        }
    }

    int catch_write_pipe_error(int err) {
        switch (err) {
        case ENOBUFS:
        case EMSGSIZE:
            return SW_REDUCE_SIZE;
        default:
            return catch_error(err);
        }
    }

    int catch_read_error(int err) const {
        return catch_error(err);
    }

    static inline SocketType convert_to_type(int domain, int type) {
        if (domain == AF_INET && type == SOCK_STREAM) {
            return SW_SOCK_TCP;
        } else if (domain == AF_INET6 && type == SOCK_STREAM) {
            return SW_SOCK_TCP6;
        } else if (domain == AF_UNIX && type == SOCK_STREAM) {
            return SW_SOCK_UNIX_STREAM;
        } else if (domain == AF_INET && type == SOCK_DGRAM) {
            return SW_SOCK_UDP;
        } else if (domain == AF_INET6 && type == SOCK_DGRAM) {
            return SW_SOCK_UDP6;
        } else if (domain == AF_UNIX && type == SOCK_DGRAM) {
            return SW_SOCK_UNIX_DGRAM;
        } else {
            return SW_SOCK_RAW;
        }
    }

    static inline SocketType convert_to_type(std::string &host) {
        if (host.compare(0, 6, "unix:/", 0, 6) == 0) {
            host = host.substr(sizeof("unix:") - 1);
            host.erase(0, host.find_first_not_of('/') - 1);
            return SW_SOCK_UNIX_STREAM;
        } else if (host.find(':') != std::string::npos) {
            return SW_SOCK_TCP6;
        } else {
            return SW_SOCK_TCP;
        }
    }

    static inline int get_domain_and_type(SocketType type, int *sock_domain, int *sock_type) {
        switch (type) {
        case SW_SOCK_TCP6:
            *sock_domain = AF_INET6;
            *sock_type = SOCK_STREAM;
            break;
        case SW_SOCK_UNIX_STREAM:
            *sock_domain = AF_UNIX;
            *sock_type = SOCK_STREAM;
            break;
        case SW_SOCK_UDP:
            *sock_domain = AF_INET;
            *sock_type = SOCK_DGRAM;
            break;
        case SW_SOCK_UDP6:
            *sock_domain = AF_INET6;
            *sock_type = SOCK_DGRAM;
            break;
        case SW_SOCK_UNIX_DGRAM:
            *sock_domain = AF_UNIX;
            *sock_type = SOCK_DGRAM;
            break;
        case SW_SOCK_TCP:
            *sock_domain = AF_INET;
            *sock_type = SOCK_STREAM;
            break;
        default:
            return SW_ERR;
        }

        return SW_OK;
    }
};

int gethostbyname(int type, const char *name, char *addr);
int getaddrinfo(GetaddrinfoRequest *req);

}  // namespace network

/**
 * This function will never return NULL; if memory allocation fails, a C++ exception will be thrown.
 * Must use the `socket->free()` function to release the object pointer instead of the `delete` operator.
 * When the socket is released, it will close the file descriptor (fd).
 * If you do not want the fd to be closed, use `socket->move_fd()` to relinquish ownership of the fd.
 */
network::Socket *make_socket(int fd, FdType fd_type);
/**
 * The following three functions will return a null pointer if the socket creation fails.
 * It is essential to check the return value;
 * if it is nullptr, you should inspect errno to determine the cause of the error.
 */
network::Socket *make_socket(SocketType socket_type, FdType fd_type, int flags);
network::Socket *make_socket(
    SocketType type, FdType fd_type, int sock_domain, int sock_type, int socket_protocol, int flags);
int socket(int sock_domain, int sock_type, int socket_protocol, int flags);
network::Socket *make_server_socket(SocketType socket_type,
                                    const char *address,
                                    int port = 0,
                                    int backlog = SW_BACKLOG);
/**
 * Verify if the input string is an IP address,
 * where AF_INET indicates an IPv4 address, such as 192.168.1.100,
 * and AF_INET6 indicates an IPv6 address, for example, 2001:0000:130F:0000:0000:09C0:876A:130B.
 */
bool verify_ip(int __af, const std::string &str);
}  // namespace swoole
