/*
The MIT License (MIT)

Copyright (c) 2013-2015 SRS(simple-rtmp-server)

Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/

#ifndef SRS_APP_HTTP_HPP
#define SRS_APP_HTTP_HPP

/*
#include <srs_app_http.hpp>
*/
#include <srs_core.hpp>

#ifdef SRS_AUTO_HTTP_PARSER

#include <map>
#include <string>
#include <vector>

#include <http_parser.h>

#include <srs_app_st.hpp>
#include <srs_http_stack.hpp>

class SrsRequest;
class SrsStSocket;
class SrsHttpMessage;
class SrsFastBuffer;
class SrsHttpUri;
class SrsConnection;

/**
 * response writer use st socket
 */
class SrsHttpResponseWriter : public ISrsHttpResponseWriter
{
private:
    SrsStSocket* skt;
    SrsHttpHeader* hdr;
private:
    // reply header has been (logically) written
    bool header_wrote;
    // status code passed to WriteHeader
    int status;
private:
    // explicitly-declared Content-Length; or -1
    int64_t content_length;
    // number of bytes written in body
    int64_t written;
private:
    // wroteHeader tells whether the header's been written to "the
    // wire" (or rather: w.conn.buf). this is unlike
    // (*response).wroteHeader, which tells only whether it was
    // logically written.
    bool header_sent;
public:
    SrsHttpResponseWriter(SrsStSocket* io);
    virtual ~SrsHttpResponseWriter();
public:
    virtual int final_request();
    virtual SrsHttpHeader* header();
    virtual int write(char* data, int size);
    virtual void write_header(int code);
    virtual int send_header(char* data, int size);
};

/**
 * response reader use st socket.
 */
class SrsHttpResponseReader : virtual public ISrsHttpResponseReader
{
private:
    SrsStSocket* skt;
    SrsHttpMessage* owner;
    SrsFastBuffer* buffer;
    bool is_eof;
    // the left bytes in chunk.
    int nb_left_chunk;
    // the number of bytes of current chunk.
    int nb_chunk;
    // already read total bytes.
    int64_t nb_total_read;
public:
    SrsHttpResponseReader(SrsHttpMessage* msg, SrsStSocket* io);
    virtual ~SrsHttpResponseReader();
public:
    /**
     * initialize the response reader with buffer.
     */
    virtual int initialize(SrsFastBuffer* buffer);
    // interface ISrsHttpResponseReader
public:
    virtual bool eof();
    virtual int read(char* data, int nb_data, int* nb_read);
private:
    virtual int read_chunked(char* data, int nb_data, int* nb_read);
    virtual int read_specified(char* data, int nb_data, int* nb_read);
};

// for http header.
typedef std::pair<std::string, std::string> SrsHttpHeaderField;

// A Request represents an HTTP request received by a server
// or to be sent by a client.
//
// The field semantics differ slightly between client and server
// usage. In addition to the notes on the fields below, see the
// documentation for Request.Write and RoundTripper.
/**
 * the http message, request or response.
 */
class SrsHttpMessage : public ISrsHttpMessage
{
private:
    /**
     * parsed url.
     */
    std::string _url;
    /**
     * the extension of file, for example, .flv
     */
    std::string _ext;
    /**
     * parsed http header.
     */
    http_parser _header;
    /**
     * body object, reader object.
     * @remark, user can get body in string by get_body().
     */
    SrsHttpResponseReader* _body;
    /**
     * whether the body is chunked.
     */
    bool chunked;
    /**
     * whether the request indicates should keep alive
     * for the http connection.
     */
    bool keep_alive;
    /**
     * uri parser
     */
    SrsHttpUri* _uri;
    /**
     * use a buffer to read and send ts file.
     */
    // TODO: FIXME: remove it.
    char* _http_ts_send_buffer;
    // http headers
    std::vector<SrsHttpHeaderField> _headers;
    // the query map
    std::map<std::string, std::string> _query;
    // the transport connection, can be NULL.
    SrsConnection* conn;
public:
    SrsHttpMessage(SrsStSocket* io, SrsConnection* c);
    virtual ~SrsHttpMessage();
public:
    /**
     * set the original messages, then update the message.
     */
    virtual int update(std::string url, http_parser* header,
        SrsFastBuffer* body, std::vector<SrsHttpHeaderField>& headers
    );
private:
    virtual SrsConnection* connection();
public:
    virtual u_int8_t method();
    virtual u_int16_t status_code();
    /**
     * method helpers.
     */
    virtual std::string method_str();
    virtual bool is_http_get();
    virtual bool is_http_put();
    virtual bool is_http_post();
    virtual bool is_http_delete();
    virtual bool is_http_options();
    /**
     * whether body is chunked encoding, for reader only.
     */
    virtual bool is_chunked();
    /**
     * whether should keep the connection alive.
     */
    virtual bool is_keep_alive();
    /**
     * the uri contains the host and path.
     */
    virtual std::string uri();
    /**
     * the url maybe the path.
     */
    virtual std::string url();
    virtual std::string host();
    virtual std::string path();
    virtual std::string ext();
public:
    /**
     * read body to string.
     * @remark for small http body.
     */
    virtual int body_read_all(std::string& body);
    /**
     * get the body reader, to read one by one.
     * @remark when body is very large, or chunked, use this.
     */
    virtual ISrsHttpResponseReader* body_reader();
    /**
     * the content length, -1 for chunked or not set.
     */
    virtual int64_t content_length();
    /**
     * get the param in query string,
     * for instance, query is "start=100&end=200",
     * then query_get("start") is "100", and query_get("end") is "200"
     */
    virtual std::string query_get(std::string key);
    /**
     * get the headers.
     */
    virtual int request_header_count();
    virtual std::string request_header_key_at(int index);
    virtual std::string request_header_value_at(int index);
    virtual std::string get_request_header(std::string name);
public:
    /**
     * convert the http message to a request.
     * @remark user must free the return request.
     */
    virtual SrsRequest* to_request(std::string vhost);
};

/**
* wrapper for http-parser, 
* provides HTTP message originted service.
*/
class SrsHttpParser
{
private:
    http_parser_settings settings;
    http_parser parser;
    // the global parse buffer.
    SrsFastBuffer* buffer;
private:
    // http parse data, reset before parse message.
    bool expect_field_name;
    std::string field_name;
    std::string field_value;
    SrsHttpParseState state;
    http_parser header;
    std::string url;
    std::vector<SrsHttpHeaderField> headers;
    int header_parsed;
public:
    SrsHttpParser();
    virtual ~SrsHttpParser();
public:
    /**
    * initialize the http parser with specified type,
    * one parser can only parse request or response messages.
    */
    virtual int initialize(enum http_parser_type type);
    /**
    * always parse a http message,
    * that is, the *ppmsg always NOT-NULL when return success.
    * or error and *ppmsg must be NULL.
    * @remark, if success, *ppmsg always NOT-NULL, *ppmsg always is_complete().
    */
    virtual int parse_message(SrsStSocket* skt, SrsConnection* conn, ISrsHttpMessage** ppmsg);
private:
    /**
    * parse the HTTP message to member field: msg.
    */
    virtual int parse_message_imp(SrsStSocket* skt);
private:
    static int on_message_begin(http_parser* parser);
    static int on_headers_complete(http_parser* parser);
    static int on_message_complete(http_parser* parser);
    static int on_url(http_parser* parser, const char* at, size_t length);
    static int on_header_field(http_parser* parser, const char* at, size_t length);
    static int on_header_value(http_parser* parser, const char* at, size_t length);
    static int on_body(http_parser* parser, const char* at, size_t length);
};

/**
* used to resolve the http uri.
*/
class SrsHttpUri
{
private:
    std::string url;
    std::string schema;
    std::string host;
    int port;
    std::string path;
    std::string query;
public:
    SrsHttpUri();
    virtual ~SrsHttpUri();
public:
    /**
    * initialize the http uri.
    */
    virtual int initialize(std::string _url);
public:
    virtual const char* get_url();
    virtual const char* get_schema();
    virtual const char* get_host();
    virtual int get_port();
    virtual const char* get_path();
    virtual const char* get_query();
private:
    /**
    * get the parsed url field.
    * @return return empty string if not set.
    */
    virtual std::string get_uri_field(std::string uri, http_parser_url* hp_u, http_parser_url_fields field);
};

#endif

#endif