/**
 * The MIT License (MIT)
 *
 * Copyright (c) 2013-2018 Winlin
 *
 * 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.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include "../../objs/include/srs_librtmp.h"

#define ERROR_INJECTED 10000

int process(const char* in_flv_file, const char* out_flv_file, srs_flv_t* pic, srs_flv_t* poc);
int build_keyframes(srs_flv_t ic, srs_amf0_t *pname, srs_amf0_t* pdata, srs_amf0_t* pfilepositions, int64_t* pmetadata_end_offset);
int do_inject_flv(srs_flv_t ic, srs_flv_t oc, srs_amf0_t amf0_name, srs_amf0_t amf0_data, srs_amf0_t filepositions, int64_t metadata_end_offset);

int main(int argc, char** argv)
{
    int ret = 0;
    
    // user options.
    char* in_flv_file;
    char* out_flv_file;
    // flv handler
    srs_flv_t ic = NULL;
    srs_flv_t oc = NULL;
    
    // temp variables.
    int tmp_file_size = 0;
    char* tmp_file;
    
    printf("inject flv file keyframes to metadata.\n");
    printf("srs(ossrs) client librtmp library.\n");
    printf("version: %d.%d.%d\n", srs_version_major(), srs_version_minor(), srs_version_revision());
    
    if (argc <= 2) {
        printf("inject flv file keyframes to metadata\n"
            "Usage: %s in_flv_file out_flv_file\n"
            "   in_flv_file         input flv file to inject.\n"
            "   out_flv_file        the inject output file, can be in_flv_file.\n"
            "For example:\n"
            "   %s doc/source.200kbps.768x320.flv injected.flv\n"
            "   %s ../../doc/source.200kbps.768x320.flv injected.flv\n",
            argv[0], argv[0], argv[0]);
        exit(-1);
    }
    
    in_flv_file = argv[1];
    out_flv_file = argv[2];
    
    tmp_file_size = strlen(out_flv_file) + strlen(".tmp") + 1;
    tmp_file = (char*)malloc(tmp_file_size);
    snprintf(tmp_file, tmp_file_size, "%s.tmp", out_flv_file);
    
    srs_human_trace("input:  %s", in_flv_file);
    srs_human_trace("output:  %s", out_flv_file);
    srs_human_trace("tmp_file:  %s", tmp_file);
    
    ret = process(in_flv_file, tmp_file, &ic, &oc);
    
    srs_flv_close(ic);
    srs_flv_close(oc);
    
    if (ret != 0) {
        unlink(tmp_file);
        if (ret == ERROR_INJECTED) {
            ret = 0;
            srs_human_trace("file already injected.");
        } else {
            srs_human_trace("error, remove tmp file.");
        }
    } else {
        rename(tmp_file, out_flv_file);
        srs_human_trace("completed, rename to %s", out_flv_file);
    }
    
    free(tmp_file);
    
    return ret;
}

int process(const char* in_flv_file, const char* out_flv_file, srs_flv_t* pic, srs_flv_t* poc)
{
    int ret = 0;
    
    srs_flv_t ic;
    srs_flv_t oc;
    
    // to adjust metadata.
    // the ic metadata end offset, the next tag start offset.
    // all oc metadata must adjust according to:
    //      adjust = new_metadata_end_offset - metadata_end_offset
    int64_t metadata_end_offset = 0;
    
    // metadata
    srs_amf0_t amf0_name = NULL;
    srs_amf0_t amf0_data = NULL;
    srs_amf0_t filepositions = NULL;
    
    if ((ic = srs_flv_open_read(in_flv_file)) == NULL) {
        ret = 2;
        srs_human_trace("open input flv file failed. ret=%d", ret);
        return ret;
    }
    *pic = ic;
    
    if ((oc = srs_flv_open_write(out_flv_file)) == NULL) {
        ret = 2;
        srs_human_trace("open output flv file failed. ret=%d", ret);
        return ret;
    }
    *poc = oc;
    
    /**
     * we use two roundtrip to avoid the paddings of metadata,
     * to support large keyframes videos without padding fields.
     */
    // build keyframes offset to metadata.
    if ((ret = build_keyframes(ic, &amf0_name, &amf0_data, &filepositions, &metadata_end_offset)) != 0) {
        return ret;
    }
    
    // inject the metadata to oc.
    if ((ret = do_inject_flv(ic, oc, amf0_name, amf0_data, filepositions, metadata_end_offset)) != 0) {
        return ret;
    }
    
    // TODO: FIXME: mem leak when error.
    srs_amf0_free(amf0_name);
    srs_amf0_free(amf0_data);
    
    return ret;
}

int parse_metadata(char* data, int size, srs_amf0_t* pname, srs_amf0_t* pdata)
{
    int ret = 0;
    
    int nparsed = 0;
    *pname = srs_amf0_parse(data, size, &nparsed);
    
    if (*pname == NULL || nparsed >= size) {
        srs_human_trace("invalid amf0 name data.");
        return -1;
    }
    
    *pdata = srs_amf0_parse(data + nparsed, size - nparsed, &nparsed);
    if (*pdata == NULL || nparsed > size) {
        srs_human_trace("invalid amf0 value data");
        return -1;
    }
    
    return ret;
}

int build_keyframes(srs_flv_t ic, srs_amf0_t *pname, srs_amf0_t* pdata, srs_amf0_t* pfilepositions, int64_t* pmetadata_end_offset)
{
    int ret = 0;
    
    // flv header
    char header[13];
    
    // packet data
    char type;
    uint32_t timestamp = 0;
    char* data = NULL;
    int32_t size;
    int64_t offset = 0;
    
    // metadata
    srs_amf0_t amf0_name = NULL;
    srs_amf0_t amf0_data = NULL;
    
    srs_amf0_t keyframes = NULL;
    srs_amf0_t filepositions = NULL;
    srs_amf0_t times = NULL;
    
    // reset to generate metadata
    srs_flv_lseek(ic, 0);
    
    if ((ret = srs_flv_read_header(ic, header)) != 0) {
        return ret;
    }
    
    srs_human_trace("build keyframe infos from flv");
    for (;;) {
        offset = srs_flv_tellg(ic);
        
        // tag header
        if ((ret = srs_flv_read_tag_header(ic, &type, &size, &timestamp)) != 0) {
            if (srs_flv_is_eof(ret)) {
                srs_human_trace("parse completed.");
                return 0;
            }
            srs_human_trace("flv get packet failed. ret=%d", ret);
            return ret;
        }
        
        if (size <= 0) {
            srs_human_trace("invalid size=%d", size);
            return ret;
        }
        
        // TODO: FIXME: mem leak when error.
        data = (char*)malloc(size);
        if ((ret = srs_flv_read_tag_data(ic, data, size)) != 0) {
            return ret;
        }
        
        // data tag
        if (type == SRS_RTMP_TYPE_VIDEO) {
            if (!srs_flv_is_sequence_header(data, size) && srs_flv_is_keyframe(data, size)) {
                srs_amf0_strict_array_append(filepositions, srs_amf0_create_number(offset));
                srs_amf0_strict_array_append(times, srs_amf0_create_number(((double)timestamp)/ 1000));
            }
        } else if (type == SRS_RTMP_TYPE_SCRIPT) {
            *pmetadata_end_offset = srs_flv_tellg(ic);
            if ((ret = parse_metadata(data, size, &amf0_name, &amf0_data)) != 0) {
                return ret;
            }
            
            *pname = amf0_name;
            *pdata = amf0_data;
            
            if (srs_amf0_is_object(amf0_data)) {
                keyframes = srs_amf0_object_property(amf0_data, "keyframes");
                if (keyframes == NULL) {
                    keyframes = srs_amf0_create_object();
                    srs_amf0_object_property_set(amf0_data, "keyframes", keyframes);
                }
                // always clear the old keyframes.
                srs_amf0_object_clear(keyframes);
                
                *pfilepositions = filepositions = srs_amf0_create_strict_array();
                srs_amf0_object_property_set(keyframes, "filepositions", filepositions);
                
                times = srs_amf0_create_strict_array();
                srs_amf0_object_property_set(keyframes, "times", times);
            } else if (srs_amf0_is_ecma_array(amf0_data)) {
                keyframes = srs_amf0_ecma_array_property(amf0_data, "keyframes");
                if (keyframes == NULL) {
                    keyframes = srs_amf0_create_object();
                    srs_amf0_ecma_array_property_set(amf0_data, "keyframes", keyframes);
                }
                // always clear the old keyframes.
                srs_amf0_object_clear(keyframes);
                
                *pfilepositions = filepositions = srs_amf0_create_strict_array();
                srs_amf0_object_property_set(keyframes, "filepositions", filepositions);
                
                times = srs_amf0_create_strict_array();
                srs_amf0_object_property_set(keyframes, "times", times);
            }
        }
        
        free(data);
    }
    
    return ret;
}

int do_inject_flv(srs_flv_t ic, srs_flv_t oc, srs_amf0_t amf0_name, srs_amf0_t amf0_data, srs_amf0_t filepositions, int64_t metadata_end_offset)
{
    int ret = 0;
    
    // flv header
    char header[13];
    // packet data
    char type;
    uint32_t timestamp = 0;
    char* data = NULL;
    int32_t size;
    
    // metadata
    srs_amf0_t fileposition = NULL;
    int amf0_name_size = 0;
    int i;
    
    // the metadata end offset, the next tag start offset.
    int64_t new_metadata_end_offset = 0;
    int offset_adjust = 0;
    
    // reset to write injected file
    srs_flv_lseek(ic, 0);
    
    if ((ret = srs_flv_read_header(ic, header)) != 0) {
        return ret;
    }
    
    if ((ret = srs_flv_write_header(oc, header)) != 0) {
        return ret;
    }
    
    // write metadata
    if (amf0_name != NULL && amf0_data != NULL) {
        amf0_name_size = srs_amf0_size(amf0_name);
        size = amf0_name_size + srs_amf0_size(amf0_data);
        
        // adjust all offset of keyframes.
        new_metadata_end_offset = srs_flv_tellg(oc) + srs_flv_size_tag(size);
        // the adjust is new offset sub the old offset of metadata end.
        offset_adjust = new_metadata_end_offset - metadata_end_offset;
        for (i = 0; i < srs_amf0_strict_array_property_count(filepositions); i++) {
            fileposition = srs_amf0_strict_array_property_at(filepositions, i);
            srs_amf0_set_number(fileposition, srs_amf0_to_number(fileposition) + offset_adjust);
        }
        
        data = (char*)malloc(size);
        memset(data, 0, size);
        if ((ret = srs_amf0_serialize(amf0_name, data, amf0_name_size)) != 0) {
            return ret;
        }
        if ((ret = srs_amf0_serialize(amf0_data, data + amf0_name_size, size - amf0_name_size)) != 0) {
            return ret;
        }
        if ((ret = srs_flv_write_tag(oc, SRS_RTMP_TYPE_SCRIPT, 0, data, size)) != 0) {
            return ret;
        }
        free(data);
    }
    
    srs_human_trace("build keyframe infos from flv");
    for (;;) {
        // tag header
        if ((ret = srs_flv_read_tag_header(ic, &type, &size, &timestamp)) != 0) {
            if (srs_flv_is_eof(ret)) {
                srs_human_trace("parse completed.");
                return 0;
            }
            srs_human_trace("flv get packet failed. ret=%d", ret);
            return ret;
        }
        
        if (size <= 0) {
            srs_human_trace("invalid size=%d", size);
            break;
        }
        
        // TODO: FIXME: mem leak when error.
        data = (char*)malloc(size);
        if ((ret = srs_flv_read_tag_data(ic, data, size)) != 0) {
            return ret;
        }
        
        // data tag
        if (type == SRS_RTMP_TYPE_SCRIPT) {
            continue;
        }
        
        // copy
        if ((ret = srs_flv_write_tag(oc, type, timestamp, data, size)) != 0) {
            return ret;
        }
        
        free(data);
    }
    
    return ret;
}