/*
    MPEG decoder plugin based on libmad
    Copyright (C) 2009-2014 Alexey Yakovenko

    This software is provided 'as-is', without any express or implied
    warranty.  In no event will the authors be held liable for any damages
    arising from the use of this software.

    Permission is granted to anyone to use this software for any purpose,
    including commercial applications, and to alter it and redistribute it
    freely, subject to the following restrictions:

    1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.

    2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.

    3. This notice may not be removed or altered from any source distribution.
*/


#include <string.h>
#include <stdio.h>
#include <mad.h>
#include <assert.h>
#include <stdlib.h>
#include <limits.h>
#include <unistd.h>
#include <sys/time.h>
#include "../../deadbeef.h"

//#define trace(...) { fprintf(stderr, __VA_ARGS__); }
#define trace(fmt,...)

//#define WRITE_DUMP 1

#if WRITE_DUMP
FILE *out;
#endif

#define min(x,y) ((x)<(y)?(x):(y))
#define max(x,y) ((x)>(y)?(x):(y))

#define likely(x)       __builtin_expect((x),1)
#define unlikely(x)     __builtin_expect((x),0)

static DB_decoder_t plugin;
static DB_functions_t *deadbeef;

#define READBUFFER 0x2800 // 10k is enough for single frame

// vbrmethod constants
#define XING_CBR  1 
#define XING_ABR  2
#define XING_VBR1 3
#define XING_VBR2 4
#define XING_VBR3 5
#define XING_VBR4 6
#define XING_CBR2 8
#define XING_ABR2 9
#define DETECTED_VBR 100

// xing header flags
#define FRAMES_FLAG     0x0001
#define BYTES_FLAG      0x0002
#define TOC_FLAG        0x0004
#define VBR_SCALE_FLAG  0x0008

typedef struct {
    DB_FILE *file;
    DB_playItem_t *it;

    // input buffer, for MPEG data
    char input[READBUFFER];
    int remaining;

    // output buffer, supplied by player
    int readsize;
    int decode_remaining; // number of decoded samples of current mpeg frame
    char *out;

    // information, filled by cmp3_scan_stream
    int version;
    int layer;
    int bitrate;
    int samplerate;
    int packetlength;
    int bitspersample;
    int channels;
    float duration;

    // currentsample and totalsamples are in the entire file scope (delay/padding inclusive)
    int currentsample;
    int totalsamples;

    int skipsamples;

    int64_t startoffset; // in bytes (id3v2, xing/lame)
    int64_t endoffset; // in bytes (apev2, id3v1)

    // startsample and endsample exclude delay/padding
    int startsample;
    int endsample;

    // number of samples to skip at the start/end of file
    int delay;
    int padding;

    float avg_packetlength;
    int avg_samplerate;
    int avg_samples_per_frame;
    int nframes;
    int last_comment_update;
    int vbr;
    int have_xing_header;
    int lead_in_frames;
} buffer_t;

typedef struct {
    DB_fileinfo_t info;
    buffer_t buffer;
    struct mad_stream stream;
    struct mad_frame frame;
    struct mad_synth synth;
} mpgmad_info_t;


static uint32_t
extract_i32 (unsigned char *buf)
{
    uint32_t x;
    // big endian extract

    x = buf[0];
    x <<= 8;
    x |= buf[1];
    x <<= 8;
    x |= buf[2];
    x <<= 8;
    x |= buf[3];

    return x;
}

static inline uint32_t
extract_i32_le (unsigned char *buf)
{
    uint32_t x;
    // little endian extract

    x = buf[3];
    x <<= 8;
    x |= buf[2];
    x <<= 8;
    x |= buf[1];
    x <<= 8;
    x |= buf[0];

    return x;
}
static inline uint16_t
extract_i16 (unsigned char *buf)
{
    uint16_t x;
    // big endian extract

    x = buf[0];
    x <<= 8;
    x |= buf[1];
    x <<= 8;

    return x;
}

static inline float
extract_f32 (unsigned char *buf) {
    float f;
    uint32_t *x = (uint32_t *)&f;
    *x = buf[0];
    *x <<= 8;
    *x |= buf[1];
    *x <<= 8;
    *x |= buf[2];
    *x <<= 8;
    *x |= buf[3];
    return f;
}

// sample=-1: scan entire stream, calculate precise duration
// sample=0: read headers/tags, calculate approximate duration
// sample>0: seek to the frame with the sample, update skipsamples
// return value: -1 on error
static int
cmp3_scan_stream (buffer_t *buffer, int sample) {
    trace ("cmp3_scan_stream %d (offs: %lld)\n", sample, deadbeef->ftell (buffer->file));

// {{{ prepare for scan - seek, reset averages, etc
    int initpos = deadbeef->ftell (buffer->file);
    trace ("initpos: %d\n", initpos);
    int packetlength = 0;
    int nframe = 0;
    int scansamples = 0;
    buffer->currentsample = 0;
    buffer->skipsamples = 0;
//    int avg_bitrate = 0;
    int valid_frames = 0;
    int prev_bitrate = -1;
    buffer->samplerate = 0;
    int64_t fsize = deadbeef->fgetlength (buffer->file);

    if (sample <= 0) {
        buffer->totalsamples = 0;
    }
    if (sample <= 0 && buffer->avg_packetlength == 0) {
        buffer->avg_packetlength = 0;
        buffer->avg_samplerate = 0;
        buffer->avg_samples_per_frame = 0;
        buffer->nframes = 0;
        trace ("setting startoffset to %d\n", initpos);
        buffer->startoffset = initpos;
    }

    int lastframe_valid = 0;
    int64_t offs = -1;
// }}}

    int64_t lead_in_frame_pos = buffer->startoffset;
    int64_t lead_in_frame_no = 0;

#define MAX_LEAD_IN_FRAMES 10
    int64_t frame_positions[MAX_LEAD_IN_FRAMES]; // positions of nframe-9, nframe-8, nframe-7, ...
    for (int i = 0; i < MAX_LEAD_IN_FRAMES; i++) {
        frame_positions[i] = buffer->startoffset;
    }

    for (;;) {
        uint32_t hdr;
        uint8_t sync;
// {{{ parse frame header, sync stream
        if (!lastframe_valid && offs >= 0) {
            deadbeef->fseek (buffer->file, offs+1, SEEK_SET);
        }
        offs = deadbeef->ftell (buffer->file);
        //uint8_t fb[4+2+2]; // 4b frame header + 2b crc + 2b sideinfo main_data_begin
        uint8_t fb[4]; // just the header
        if (deadbeef->fread (fb, 1, sizeof(fb), buffer->file) != sizeof(fb)) {
            break; // eof
        }

retry_sync:

        sync = fb[0];
        if (sync != 0xff) {
//            trace ("[1]frame %d didn't seek to frame end\n", nframe);
            lastframe_valid = 0;
            memmove (fb, fb+1, 3);
            if (deadbeef->fread (fb+3, 1, 1, buffer->file) != 1) {
                break; // eof
            }
            offs++;
            goto retry_sync; // not an mpeg frame
        }
        else {
            // 2nd sync byte
            sync = fb[1];
            if ((sync >> 5) != 7) {
//                trace ("[2]frame %d didn't seek to frame end\n", nframe);
                lastframe_valid = 0;
                memmove (fb, fb+1, 3);
                if (deadbeef->fread (fb+3, 1, 1, buffer->file) != 1) {
                    break; // eof
                }
                offs++;
                goto retry_sync; // not an mpeg frame
            }
        }
        // found frame
        hdr = (0xff<<24) | (sync << 16);
        sync = fb[2];
        hdr |= sync << 8;
        sync = fb[3];
        hdr |= sync;

        // parse header
        
        // sync bits
        int usync = hdr & 0xffe00000;
        if (usync != 0xffe00000) {
            fprintf (stderr, "fatal error: mp3 header parser is broken\n");
        }

        // mpeg version
        static const int vertbl[] = {3, -1, 2, 1}; // 3 is 2.5
        int ver = (hdr & (3<<19)) >> 19;
        ver = vertbl[ver];
        if (ver < 0) {
            trace ("frame %d bad mpeg version %d\n", nframe, (hdr & (3<<19)) >> 19);
            lastframe_valid = 0;
            continue; // invalid frame
        }

        // layer info
        static const int ltbl[] = { -1, 3, 2, 1 };
        int layer = (hdr & (3<<17)) >> 17;
        layer = ltbl[layer];
        if (layer < 0) {
            trace ("frame %d bad layer %d\n", nframe, (hdr & (3<<17)) >> 17);
            lastframe_valid = 0;
            continue; // invalid frame
        }

        // protection bit (crc)
//        int prot = (hdr & (1<<16)) >> 16;

        // bitrate
        static const int brtable[5][16] = {
            { 0, 32, 64, 96, 128, 160, 192, 224, 256, 288, 320, 352, 384, 416, 448, -1 },
            { 0, 32, 48, 56,  64,  80,  96, 112, 128, 160, 192, 224, 256, 320, 384, -1 },
            { 0, 32, 40, 48,  56,  64,  80,  96, 112, 128, 160, 192, 224, 256, 320, -1 },
            { 0, 32, 48, 56,  64,  80,  96, 112, 128, 144, 160, 176, 192, 224, 256, -1 },
            { 0,  8, 16, 24,  32,  40,  48,  56,  64,  80,  96, 112, 128, 144, 160, -1 }
        };
        int bitrate = (hdr & (0x0f<<12)) >> 12;
        int idx = 0;
        if (ver == 1) {
            idx = layer - 1;
        }
        else {
            idx = layer == 1 ? 3 : 4;
        }
        bitrate = brtable[idx][bitrate];
        if (bitrate <= 0) {
            trace ("frame %d bad bitrate %d\n", nframe, (hdr & (0x0f<<12)) >> 12);
            lastframe_valid = 0;
            continue; // invalid frame
        }

        // samplerate
        static const int srtable[3][4] = {
            {44100, 48000, 32000, -1},
            {22050, 24000, 16000, -1},
            {11025, 12000, 8000, -1},
        };
        int samplerate = (hdr & (0x03<<10))>>10;
        samplerate = srtable[ver-1][samplerate];
        if (samplerate < 0) {
            trace ("frame %d bad samplerate %d\n", nframe, (hdr & (0x03<<10))>>10);
            lastframe_valid = 0;
            continue; // invalid frame
        }

        // padding
        int padding = (hdr & (0x1 << 9)) >> 9;

        static const int chantbl[4] = { 2, 2, 2, 1 };
        int nchannels = (hdr & (0x3 << 6)) >> 6;
        nchannels = chantbl[nchannels];

        // check if channel/bitrate combination is valid for layer2
        if (layer == 2) {
            if ((bitrate <= 56 || bitrate == 80) && nchannels != 1) {
                trace ("mpgmad: bad frame %d: layer %d, channels %d, bitrate %d\n", nframe, layer, nchannels, bitrate);
                lastframe_valid = 0;
                continue; // bad frame
            }
            if (bitrate >= 224 && nchannels == 1) {
                trace ("mpgmad: bad frame %d: layer %d, channels %d, bitrate %d\n", nframe, layer, nchannels, bitrate);
                lastframe_valid = 0;
                continue; // bad frame
            }
        }
// }}}

// {{{ get side info ptr
//        uint8_t *si = fb + 4;
//        if (prot) {
//            si += 2;
//        }
//        int data_ptr = ((uint16_t)si[1]) | (((uint16_t)si[1]&0)<<8);
// }}}

// {{{ calc packet length, number of samples in a frame
        // packetlength
        packetlength = 0;
        bitrate *= 1000;
        int samples_per_frame = 0;
        if (samplerate > 0 && bitrate > 0) {
            if (layer == 1) {
                samples_per_frame = 384;
            }
            else if (layer == 2) {
                samples_per_frame = 1152;
            }
            else if (layer == 3) {
                if (ver == 1) {
                    samples_per_frame = 1152;
                }
                else {
                    samples_per_frame = 576;
                }
            }
            packetlength = samples_per_frame / 8 * bitrate / samplerate + padding;
//            if (sample > 0) {
//                printf ("frame: %d, crc: %d, layer: %d, bitrate: %d, samplerate: %d, filepos: 0x%llX, dataoffs: 0x%X, size: 0x%X\n", nframe, prot, layer, bitrate, samplerate, deadbeef->ftell (buffer->file)-8, data_ptr, packetlength);
//            }
        }
        else {
            trace ("frame %d samplerate or bitrate is invalid\n", nframe);
            lastframe_valid = 0;
            continue;
        }
// }}}

// {{{ vbr adjustement
        if (!buffer->have_xing_header && prev_bitrate != -1 && prev_bitrate != bitrate) {
            buffer->vbr = DETECTED_VBR;
        }
        prev_bitrate = bitrate;
// }}}

        valid_frames++;

// {{{ update stream parameters, only when sample!=0 or 1st frame
        if (sample != 0 || nframe == 0)
        {
            if (sample == 0 && lastframe_valid) {
                return 0;
            }
            // don't get parameters from frames coming after any bad frame
            buffer->version = ver;
            buffer->layer = layer;
            buffer->bitrate = bitrate;
            buffer->samplerate = samplerate;
            buffer->packetlength = packetlength;
            if (nchannels > buffer->channels) {
                buffer->channels = nchannels;
            }
            buffer->bitspersample = 16;
//            trace ("frame %d mpeg v%d layer %d bitrate %d samplerate %d packetlength %d channels %d\n", nframe, ver, layer, bitrate, samplerate, packetlength, nchannels);
        }
// }}}

        lastframe_valid = 1;

        int64_t framepos = deadbeef->ftell (buffer->file)-(int)sizeof(fb);

        // allow at least 10 lead-in frames, to fill bit-reservoir
        if (nframe - lead_in_frame_no > MAX_LEAD_IN_FRAMES) {
            lead_in_frame_pos = frame_positions[0];
            lead_in_frame_no++;
        }
        memmove (frame_positions, &frame_positions[1], sizeof (int64_t) * (MAX_LEAD_IN_FRAMES-1));
        frame_positions[MAX_LEAD_IN_FRAMES-1] = framepos;

// {{{ detect/load xing frame, only on 1st pass
        // try to read xing/info tag (only on initial scans)
        if (sample <= 0 && !buffer->have_xing_header)
        {
            if (!buffer->file->vfs->is_streaming ()) {
                //            trace ("trying to read xing header at pos %d\n", framepos);
                if (ver == 1) {
                    deadbeef->fseek (buffer->file, 32/*-2-2*prot*/, SEEK_CUR);
                }
                else if (ver == 2) {
                    // in mpeg2 streams, sideinfo is 17 bytes
                    deadbeef->fseek (buffer->file, 17/*-2-prot*2*/, SEEK_CUR);
                }
                const char xing[] = "Xing";
                const char info[] = "Info";
                char magic[4];
                if (deadbeef->fread (magic, 1, 4, buffer->file) != 4) {
                    trace ("cmp3_scan_stream: EOF while checking for Xing header\n");
                    return -1; // EOF
                }

                //            trace ("xing magic: %c%c%c%c\n", magic[0], magic[1], magic[2], magic[3]);

                if (!strncmp (xing, magic, 4) || !strncmp (info, magic, 4)) {
                    trace ("xing/info frame found\n");
                    buffer->startoffset += packetlength;
                    // read flags
                    uint32_t flags;
                    uint8_t buf[4];
                    if (deadbeef->fread (buf, 1, 4, buffer->file) != 4) {
                        trace ("cmp3_scan_stream: EOF while parsing Xing header\n");
                        return -1; // EOF
                    }
                    flags = extract_i32 (buf);
                    if (flags & FRAMES_FLAG) {
                        // read number of frames
                        if (deadbeef->fread (buf, 1, 4, buffer->file) != 4) {
                            trace ("cmp3_scan_stream: EOF while parsing Xing header\n");
                            return -1; // EOF
                        }
                        uint32_t nframes = extract_i32 (buf);
                        if (sample == 0) {
                            buffer->duration = (((uint64_t)nframes * (uint64_t)samples_per_frame) - buffer->delay - buffer->padding)/ (float)samplerate;
                        }
                        trace ("xing totalsamples: %d, nframes: %d, samples_per_frame: %d\n", nframes*samples_per_frame, nframes, samples_per_frame);
                        if (nframes <= 0 || samples_per_frame <= 0) {
                            trace ("bad xing header\n");
                            continue;
                        }
                        buffer->totalsamples = nframes * samples_per_frame;
                        buffer->samplerate = samplerate;
                    }
                    if (flags & BYTES_FLAG) {
                        deadbeef->fseek (buffer->file, 4, SEEK_CUR);
                    }
                    if (flags & TOC_FLAG) {
                        deadbeef->fseek (buffer->file, 100, SEEK_CUR);
                    }
                    if (flags & VBR_SCALE_FLAG) {
                        deadbeef->fseek (buffer->file, 4, SEEK_CUR);
                    }
                    // lame header
                    if (deadbeef->fread (buf, 1, 4, buffer->file) != 4) {
                        trace ("cmp3_scan_stream: EOF while reading LAME header\n");
                        return -1; // EOF
                    }
                    //                trace ("tell=%x, %c%c%c%c\n", deadbeef->ftell(buffer->file), buf[0], buf[1], buf[2], buf[3]);

                    deadbeef->fseek (buffer->file, 5, SEEK_CUR);
                    uint8_t rev = 0;
                    if (deadbeef->fread (&rev, 1, 1, buffer->file) != 1) {
                        trace ("cmp3_scan_stream: EOF while reading info tag revision / vbr method\n");
                    }
                    switch (rev & 0x0f) {
                    case XING_ABR ... XING_VBR4:
                    case XING_ABR2:
                        buffer->vbr = rev & 0x0f;
                        break;
                    default:
                        buffer->vbr = DETECTED_VBR;
                        break;
                    }
                    if (!memcmp (buf, "LAME", 4)) {
                        trace ("lame header found\n");

                        // FIXME: that can be optimized by single read
                        uint8_t lpf;
                        deadbeef->fread (&lpf, 1, 1, buffer->file);
                        //3 floats: replay gain
                        deadbeef->fread (buf, 1, 4, buffer->file);
                        // float rg_peaksignalamp = extract_f32 (buf);
                        deadbeef->fread (buf, 1, 2, buffer->file);
                        // uint16_t rg_radio = extract_i16 (buf);

                        deadbeef->fread (buf, 1, 2, buffer->file);
                        // uint16_t rg_audiophile = extract_i16 (buf);

                        // skip
                        deadbeef->fseek (buffer->file, 2, SEEK_CUR);
                        deadbeef->fread (buf, 1, 3, buffer->file);
                        buffer->delay = (((uint32_t)buf[0]) << 4) | ((((uint32_t)buf[1]) & 0xf0)>>4);
                        buffer->padding = ((((uint32_t)buf[1])&0x0f)<<8) | ((uint32_t)buf[2]);
                        // skip
                        deadbeef->fseek (buffer->file, 1, SEEK_CUR);
                        // mp3gain
                        uint8_t mp3gain;
                        deadbeef->fread (&mp3gain, 1, 1, buffer->file);
                        // skip
                        deadbeef->fseek (buffer->file, 2, SEEK_CUR);
                        // musiclen
                        deadbeef->fread (buf, 1, 4, buffer->file);
                        //                    uint32_t musiclen = extract_i32 (buf);

                        //trace ("lpf: %d, peaksignalamp: %f, radiogain: %d, audiophile: %d, delay: %d, padding: %d, mp3gain: %d, musiclen: %d\n", lpf, rg_peaksignalamp, rg_radio, rg_audiophile, delay, padding, mp3gain, musiclen);
                        // skip crc
                        //deadbeef->fseek (buffer->file, 4, SEEK_CUR);
                        trace ("lame totalsamples: %d\n", buffer->totalsamples);
                    }
                    if (sample <= 0 && (flags&FRAMES_FLAG)) {
                        buffer->have_xing_header = 1;
                        buffer->startoffset = framepos+packetlength;
                        deadbeef->fseek (buffer->file, buffer->startoffset, SEEK_SET);
                        if (fsize >= 0) {
                            buffer->bitrate = (fsize - buffer->startoffset - buffer->endoffset)/ buffer->samplerate * 1000;
                        }
                    }
                }
            }
            if (sample == 0) {
                if (buffer->file->vfs->is_streaming ()) {
                    // only suitable for cbr files, used if streaming
                    int sz = deadbeef->fgetlength (buffer->file);
                    if (sz > 0) {
                        sz -= buffer->startoffset + buffer->endoffset;
                        if (sz < 0) {
                            trace ("cmp3_scan_stream: bad file headers\n");
                            return -1;
                        }
                    }
                    if (sz < 0) {
                        // unable to determine duration
                        buffer->duration = -1;
                        buffer->totalsamples = -1;
                        if (sample == 0) {
                            trace ("check validity of the next frame...\n");
                            deadbeef->fseek (buffer->file, framepos+packetlength, SEEK_SET);
                            continue;
                        }
                        trace ("cmp3_scan_stream: unable to determine duration");
                        return 0;
                    }
                    buffer->nframes = sz / packetlength;
                    buffer->avg_packetlength = packetlength;
                    buffer->avg_samplerate = samplerate;
                    buffer->avg_samples_per_frame = samples_per_frame;
                    buffer->duration = (((uint64_t)buffer->nframes * (uint64_t)samples_per_frame) - buffer->delay - buffer->padding)/ (float)samplerate;
                    buffer->totalsamples = buffer->nframes * samples_per_frame;
                    trace ("totalsamples: %d, samplesperframe: %d, fsize=%lld\n", buffer->totalsamples, samples_per_frame, fsize);
//                    trace ("bitrate=%d, layer=%d, packetlength=%d, fsize=%d, nframes=%d, samples_per_frame=%d, samplerate=%d, duration=%f, totalsamples=%d\n", bitrate, layer, packetlength, sz, nframe, samples_per_frame, samplerate, buffer->duration, buffer->totalsamples);

                    if (sample == 0) {
                        deadbeef->fseek (buffer->file, framepos, SEEK_SET);
                        return 0;
                    }
                }
                else {
                    deadbeef->fseek (buffer->file, framepos, SEEK_SET);
                }
            }
            else {
                deadbeef->fseek (buffer->file, framepos+packetlength, SEEK_SET);
                buffer->have_xing_header = 1;
            }
        }
// }}}

        if (sample == 0) {
// {{{ update averages, interrupt scan on frame #100
            if (fsize <= 0) {
                trace ("cmp3_scan_stream: negative file size\n");
                return -1;
            }
            // calculating apx duration based on 1st 100 frames
            buffer->avg_packetlength += packetlength;
            buffer->avg_samplerate += samplerate;
            buffer->avg_samples_per_frame += samples_per_frame;
            //avg_bitrate += bitrate;
            if (nframe >= 100) {
                goto end_scan;
            }
// }}}
        }
        else {
            // seeking to particular sample, interrupt if reached
            if (sample > 0 && scansamples + samples_per_frame >= sample) {
                deadbeef->fseek (buffer->file, lead_in_frame_pos, SEEK_SET);
                buffer->lead_in_frames = nframe-lead_in_frame_no;
                buffer->currentsample = sample;
                buffer->skipsamples = sample - scansamples;
                trace ("scan: cursample=%d, frame: %d, skipsamples: %d, filepos: %llX, lead-in frames: %d\n", buffer->currentsample, nframe, buffer->skipsamples, deadbeef->ftell (buffer->file), buffer->lead_in_frames);
                return 0;
            }
        }
        scansamples += samples_per_frame;
        nframe++;
        if (packetlength > 0) {
            deadbeef->fseek (buffer->file, packetlength-(int)sizeof(fb), SEEK_CUR);
        }
    }
end_scan:
    if (nframe == 0) {
        trace ("cmp3_scan_stream: couldn't find mpeg frames in file\n");
        return -1;
    }
    if (sample == 0) {
// {{{ calculate final averages
        buffer->avg_packetlength /= (float)valid_frames;
        buffer->avg_samplerate /= valid_frames;
        buffer->avg_samples_per_frame /= valid_frames;
//        avg_bitrate /= valid_frames;
        //trace ("valid_frames=%d, avg_bitrate=%d, avg_packetlength=%f, avg_samplerate=%d, avg_samples_per_frame=%d\n", valid_frames, avg_bitrate, buffer->avg_packetlength, buffer->avg_samplerate, buffer->avg_samples_per_frame);
        trace ("startoffs: %lld, endoffs: %lld\n",  buffer->startoffset, buffer->endoffset);

        buffer->nframes = (fsize - buffer->startoffset - buffer->endoffset) / buffer->avg_packetlength;
        if (!buffer->have_xing_header) {
            buffer->totalsamples = buffer->nframes * buffer->avg_samples_per_frame;
            buffer->duration = (buffer->totalsamples - buffer->delay - buffer->padding) / (float)buffer->avg_samplerate;
        }
        buffer->bitrate = (fsize - buffer->startoffset - buffer->endoffset) / buffer->duration * 8;
        trace ("nframes: %d, fsize: %lld, spf: %d, smp: %d, totalsamples: %d\n", buffer->nframes, fsize, buffer->avg_samples_per_frame, buffer->avg_samplerate, buffer->totalsamples);
// }}}
        return 0;
    }

    buffer->totalsamples = scansamples;
    buffer->duration = (buffer->totalsamples - buffer->delay - buffer->padding) / (float)buffer->samplerate;
//    printf ("nframes=%d, totalsamples=%d, samplerate=%d, dur=%f\n", nframe, scansamples, buffer->samplerate, buffer->duration);
    return 0;
}

int
cmp3_seek_stream (DB_fileinfo_t *_info, int sample) {
    mpgmad_info_t *info = (mpgmad_info_t *)_info;
    if (sample == 0) {
        _info->readpos = 0;
        info->buffer.currentsample = 0;
        info->buffer.skipsamples = 0;
        return 0;

    }
#if WRITE_DUMP
    if (out) {
        fclose (out);
        out = fopen ("out.raw", "w+b");
    }
#endif

    int res = cmp3_scan_stream (&info->buffer, sample);
    return res;
}


static DB_fileinfo_t *
cmp3_open (uint32_t hints) {
    DB_fileinfo_t *_info = malloc (sizeof (mpgmad_info_t));
    mpgmad_info_t *info = (mpgmad_info_t *)_info;
    memset (info, 0, sizeof (mpgmad_info_t));
    return _info;
}

void
cmp3_set_extra_properties (buffer_t *buffer, int fake) {
    char s[100];
    int64_t size = deadbeef->fgetlength (buffer->file);
    if (size >= 0) {
        snprintf (s, sizeof (s), "%lld", size);
        deadbeef->pl_replace_meta (buffer->it, ":FILE_SIZE", s);
    }
    else {
        deadbeef->pl_replace_meta (buffer->it, ":FILE_SIZE", "∞");
    }
    if (buffer->bitrate > 0) {
        snprintf (s, sizeof (s), "%d", buffer->bitrate/1000);
        deadbeef->pl_replace_meta (buffer->it, ":BITRATE", s);
    }
    deadbeef->pl_replace_meta (buffer->it, ":BPS", "16");
    snprintf (s, sizeof (s), "%d", buffer->channels);
    deadbeef->pl_replace_meta (buffer->it, ":CHANNELS", s);
    snprintf (s, sizeof (s), "%d", buffer->samplerate);
    deadbeef->pl_replace_meta (buffer->it, ":SAMPLERATE", s);

    // set codec profile (cbr or vbr) and mp3 vbr method (guessed, or from Xing/Info header)

    switch (buffer->vbr) {
    case XING_ABR:
        deadbeef->pl_replace_meta (buffer->it, ":CODEC_PROFILE", "VBR");
        deadbeef->pl_replace_meta (buffer->it, ":MP3_VBR_METHOD", "ABR");
        break;
    case XING_VBR1:
        deadbeef->pl_replace_meta (buffer->it, ":CODEC_PROFILE", "VBR");
        deadbeef->pl_replace_meta (buffer->it, ":MP3_VBR_METHOD", "full VBR method 1");
        break;
    case XING_VBR2:
        deadbeef->pl_replace_meta (buffer->it, ":CODEC_PROFILE", "VBR");
        deadbeef->pl_replace_meta (buffer->it, ":MP3_VBR_METHOD", "full VBR method 2");
        break;
    case XING_VBR3:
        deadbeef->pl_replace_meta (buffer->it, ":CODEC_PROFILE", "VBR");
        deadbeef->pl_replace_meta (buffer->it, ":MP3_VBR_METHOD", "full VBR method 3");
        break;
    case XING_VBR4:
        deadbeef->pl_replace_meta (buffer->it, ":CODEC_PROFILE", "VBR");
        deadbeef->pl_replace_meta (buffer->it, ":MP3_VBR_METHOD", "full VBR method 4");
        break;
    case XING_CBR2:
        deadbeef->pl_replace_meta (buffer->it, ":CODEC_PROFILE", "CBR");
        break;
    case XING_ABR2:
        deadbeef->pl_replace_meta (buffer->it, ":CODEC_PROFILE", "VBR");
        deadbeef->pl_replace_meta (buffer->it, ":MP3_VBR_METHOD", "ABR 2 pass");
        break;
    case DETECTED_VBR:
        deadbeef->pl_replace_meta (buffer->it, ":CODEC_PROFILE", "VBR");
        deadbeef->pl_replace_meta (buffer->it, ":MP3_VBR_METHOD", "unspecified");
        break;
    default:
        deadbeef->pl_replace_meta (buffer->it, ":CODEC_PROFILE", "CBR");
        break;
    }
    const char *versions[] = {"1", "2", "2.5"};
    snprintf (s, sizeof (s), "MPEG%s layer%d", versions[buffer->version-1], buffer->layer);
    deadbeef->pl_replace_meta (buffer->it, ":MPEG_VERSION", s);
    deadbeef->pl_replace_meta (buffer->it, ":XING_HEADER", buffer->have_xing_header ? "Yes" : "No");
    deadbeef->pl_replace_meta (buffer->it, fake ? "!FILETYPE" : ":FILETYPE", "MP3");
}

static int
cmp3_init (DB_fileinfo_t *_info, DB_playItem_t *it) {
    mpgmad_info_t *info = (mpgmad_info_t *)_info;
    _info->plugin = &plugin;
    memset (&info->buffer, 0, sizeof (info->buffer));
    deadbeef->pl_lock ();
    info->buffer.file = deadbeef->fopen (deadbeef->pl_find_meta (it, ":URI"));
    deadbeef->pl_unlock ();
    if (!info->buffer.file) {
        return -1;
    }
    info->info.file = info->buffer.file;
    deadbeef->pl_item_ref (it);
    info->buffer.it = it;
    info->info.readpos = 0;
    if (!info->buffer.file->vfs->is_streaming ()) {
        int skip = deadbeef->junk_get_leading_size (info->buffer.file);
        if (skip > 0) {
            trace ("mpgmad: skipping %d(%xH) bytes of junk\n", skip, skip);
            deadbeef->fseek (info->buffer.file, skip, SEEK_SET);
        }
        int res = cmp3_scan_stream (&info->buffer, deadbeef->conf_get_int ("mp3.disable_gapless", 0) ? 0 : -1);
        if (res < 0) {
            trace ("mpgmad: cmp3_init: initial cmp3_scan_stream failed\n");
            return -1;
        }
        info->buffer.delay += 529;
        if (info->buffer.padding >= 529) {
            info->buffer.padding -= 529;
        }
        if (it->endsample > 0) {
            info->buffer.startsample = it->startsample + info->buffer.delay;
            info->buffer.endsample = it->endsample + info->buffer.delay;
            // that comes from cue, don't calc duration, just seek and play
            trace ("mp3 totalsamples: %d\n", info->buffer.endsample-info->buffer.startsample+1);
        }
        else {
            ddb_playlist_t *plt = deadbeef->pl_get_playlist (it);
            deadbeef->plt_set_item_duration (plt, it, info->buffer.duration);
            if (plt) {
                deadbeef->plt_unref (plt);
            }
            info->buffer.startsample = info->buffer.delay;
            info->buffer.endsample = info->buffer.totalsamples-info->buffer.padding-1;
            trace ("mp3 totalsamples: %d (%d, %d, %d | %d %d)\n", info->buffer.endsample-info->buffer.startsample+1, info->buffer.totalsamples, info->buffer.delay, info->buffer.padding, info->buffer.startsample, info->buffer.endsample);
            trace ("mpgmad: seeking to %d(%xH) start offset\n", info->buffer.startoffset, info->buffer.startoffset);
            deadbeef->fseek (info->buffer.file, info->buffer.startoffset, SEEK_SET);
        }
        plugin.seek_sample (_info, 0);
        trace ("mp3: startsample: %d, endsample: %d, currentsample: %d\n", info->buffer.startsample, info->buffer.endsample, info->buffer.currentsample);
    }
    else {
        deadbeef->fset_track (info->buffer.file, it);
        deadbeef->pl_add_meta (it, "title", NULL);
        int res = cmp3_scan_stream (&info->buffer, 0);
        if (res < 0) {
            trace ("mpgmad: cmp3_init: initial cmp3_scan_stream failed\n");
            return -1;
        }
        deadbeef->fseek (info->buffer.file, 0, SEEK_SET);

        cmp3_set_extra_properties (&info->buffer, 1);

        ddb_playlist_t *plt = deadbeef->pl_get_playlist (it);
        deadbeef->plt_set_item_duration (plt, it, info->buffer.duration);
        if (plt) {
            deadbeef->plt_unref (plt);
        }
        if (info->buffer.duration >= 0) {
            info->buffer.endsample = info->buffer.totalsamples - 1;
        }
        else {
//            info->buffer.duration = 200;
//            info->buffer.totalsamples = 10000000;
//            info->buffer.endsample = info->buffer.totalsamples-1;
            info->buffer.endsample = -1;
            info->buffer.totalsamples = -1;
        }
        info->buffer.skipsamples = 0;
        info->buffer.currentsample = 0;
        if (info->buffer.duration < 0) {
            info->buffer.duration = -1;
            info->buffer.totalsamples = -1;
            info->buffer.endsample = -1;
        }
        trace ("duration=%f, endsample=%d, totalsamples=%d\n", info->buffer.duration, info->buffer.endsample, info->buffer.totalsamples);
    }
    if (info->buffer.samplerate == 0) {
        trace ("bad mpeg file: %s\n", deadbeef->pl_find_meta (it, ":URI"));
        return -1;
    }
    _info->fmt.bps = info->buffer.bitspersample;
    _info->fmt.samplerate = info->buffer.samplerate;
    _info->fmt.channels = info->buffer.channels;
    _info->fmt.channelmask = _info->fmt.channels == 1 ? DDB_SPEAKER_FRONT_LEFT : (DDB_SPEAKER_FRONT_LEFT | DDB_SPEAKER_FRONT_RIGHT);
    trace ("mp3 format: bps:%d sr:%d channels:%d\n", _info->fmt.bps, _info->fmt.samplerate, _info->fmt.channels);

	mad_stream_init(&info->stream);
	mad_stream_options (&info->stream, MAD_OPTION_IGNORECRC);
	mad_frame_init(&info->frame);
	mad_synth_init(&info->synth);

    return 0;
}

/****************************************************************************
 * Converts a sample from libmad's fixed point number format to a signed	*
 * short (16 bits).															*
 ****************************************************************************/
static inline int16_t
MadFixedToSshort(mad_fixed_t Fixed)
{
	/* A fixed point number is formed of the following bit pattern:
	 *
	 * SWWWFFFFFFFFFFFFFFFFFFFFFFFFFFFF
	 * MSB                          LSB
	 * S ==> Sign (0 is positive, 1 is negative)
	 * W ==> Whole part bits
	 * F ==> Fractional part bits
	 *
	 * This pattern contains MAD_F_FRACBITS fractional bits, one
	 * should alway use this macro when working on the bits of a fixed
	 * point number. It is not guaranteed to be constant over the
	 * different platforms supported by libmad.
	 *
	 * The signed short value is formed, after clipping, by the least
	 * significant whole part bit, followed by the 15 most significant
	 * fractional part bits. Warning: this is a quick and dirty way to
	 * compute the 16-bit number, madplay includes much better
	 * algorithms.
	 */

	/* Clipping */
	if(Fixed>=MAD_F_ONE)
		return(32767);
	if(Fixed<=-MAD_F_ONE)
		return(-32768);

	/* Conversion. */
	Fixed=Fixed>>(MAD_F_FRACBITS-15);
	return((signed short)Fixed);
}

static inline float
MadFixedToFloat (mad_fixed_t Fixed) {
    return (float)((Fixed) / (float)(1L << MAD_F_FRACBITS));
}

#define MadErrorString(x) mad_stream_errorstr(x)

static inline void
cmp3_skip (mpgmad_info_t *info) {
    if (info->buffer.skipsamples > 0) {
        int skip = min (info->buffer.skipsamples, info->buffer.decode_remaining);
//        printf ("skip %d / %d\n", skip, info->buffer.skipsamples);
        info->buffer.skipsamples -= skip;
        info->buffer.decode_remaining -= skip;
    }
}

#if 0
static void
dump_buffer (buffer_t *buffer) {
    printf ("*** DUMP ***\n");
    printf ("remaining: %d\n", buffer->remaining);

    printf ("readsize: %d\n", buffer->readsize);
    printf ("decode_remaining: %d\n", buffer->decode_remaining);

    // information, filled by cmp3_scan_stream
    printf ("%d\n", buffer->version);
    printf ("%d\n", buffer->layer);
    printf ("%d\n", buffer->bitrate);
    printf ("%d\n", buffer->samplerate);
    printf ("%d\n", buffer->packetlength);
    printf ("%d\n", buffer->bitspersample);
    printf ("%d\n", buffer->channels);
    printf ("%f\n", buffer->duration);

    printf ("%d\n", buffer->currentsample);
    printf ("%d\n", buffer->totalsamples);
    printf ("%d\n", buffer->skipsamples);
    printf ("%d\n", buffer->startoffset);
    printf ("%d\n", buffer->endoffset);
    printf ("%d\n", buffer->startsample);
    printf ("%d\n", buffer->endsample);
    printf ("%d\n", buffer->delay);
    printf ("%d\n", buffer->padding);

    printf ("%f\n", buffer->avg_packetlength);
    printf ("%d\n", buffer->avg_samplerate);
    printf ("%d\n", buffer->avg_samples_per_frame);
    printf ("%d\n", buffer->nframes);
    printf ("%d\n", buffer->last_comment_update);
    printf ("%d\n", buffer->vbr);
    printf ("%d\n", buffer->have_xing_header);
    printf ("%d\n", buffer->current_decode_frame);
    printf ("%lld\n", buffer->lastframe_filepos);

    printf ("*** END ***\n");
}
#endif

// decoded requested number of samples to int16 format
static void
cmp3_decode_requested_int16 (mpgmad_info_t *info) {
    cmp3_skip (info);
    if (info->buffer.skipsamples > 0) {
        return;
    }
    // copy synthesized samples into readbuffer
    int idx = info->synth.pcm.length-info->buffer.decode_remaining;

    // stereo
    if (MAD_NCHANNELS(&info->frame.header) == 2 && info->info.fmt.channels == 2) {
        while (info->buffer.decode_remaining > 0 && info->buffer.readsize > 0) {
            *((int16_t*)info->buffer.out) = MadFixedToSshort (info->synth.pcm.samples[0][idx]);
            info->buffer.readsize -= 2;
            info->buffer.out += 2;
            *((int16_t*)info->buffer.out) = MadFixedToSshort (info->synth.pcm.samples[1][idx]);
            info->buffer.readsize -= 2;
            info->buffer.out += 2;
            info->buffer.decode_remaining--;
            idx++;
        }
    }
    // mono
    else if (MAD_NCHANNELS(&info->frame.header) == 1 && info->info.fmt.channels == 1){
        while (info->buffer.decode_remaining > 0 && info->buffer.readsize > 0) {
            *((int16_t*)info->buffer.out) = MadFixedToSshort (info->synth.pcm.samples[0][idx]);
            info->buffer.readsize -= 2;
            info->buffer.out += 2;
            info->buffer.decode_remaining--;
            idx++;
        }
    }
    // workaround for bad mp3s that have both mono and stereo frames
    else if (MAD_NCHANNELS(&info->frame.header) == 1 && info->info.fmt.channels == 2) {
        while (info->buffer.decode_remaining > 0 && info->buffer.readsize > 0) {
            int16_t sample = MadFixedToSshort (info->synth.pcm.samples[0][idx]);
            *((int16_t*)info->buffer.out) = sample;
            info->buffer.readsize -= 2;
            info->buffer.out += 2;
            *((int16_t*)info->buffer.out) = sample;
            info->buffer.readsize -= 2;
            info->buffer.out += 2;
            info->buffer.decode_remaining--;
            idx++;
        }
    }
    else if (MAD_NCHANNELS(&info->frame.header) == 2 && info->info.fmt.channels == 1) {
        while (info->buffer.decode_remaining > 0 && info->buffer.readsize > 0) {
            int16_t sample = MadFixedToSshort (info->synth.pcm.samples[0][idx]);
            *((int16_t*)info->buffer.out) = sample;
            info->buffer.readsize -= 2;
            info->buffer.out += 2;
            info->buffer.decode_remaining--;
            idx++;
        }
    }
    assert (info->buffer.readsize >= 0);
}

static int
cmp3_stream_frame (mpgmad_info_t *info) {
    int eof = 0;
    while (!eof && (info->stream.buffer == NULL || info->buffer.decode_remaining <= 0)) {
        // read more MPEG data if needed
        if(info->stream.buffer==NULL || info->stream.error==MAD_ERROR_BUFLEN) {
            // copy part of last frame to beginning
            if (info->stream.next_frame && info->stream.bufend <= info->stream.next_frame) {
                eof = 1;
                break;
            }
            if (info->stream.next_frame != NULL) {
                info->buffer.remaining = info->stream.bufend - info->stream.next_frame;
                memmove (info->buffer.input, info->stream.next_frame, info->buffer.remaining);
            }
            int size = READBUFFER - info->buffer.remaining;
            int bytesread = 0;
            uint8_t *bytes = info->buffer.input + info->buffer.remaining;
            bytesread = deadbeef->fread (bytes, 1, size, info->buffer.file);
            if (!bytesread) {
                // add guard
                eof = 1;
                memset (bytes, 0, 8);
                bytesread = 8;
            }
            if (bytesread < size) {
                // end of file
                size -= bytesread;
                bytes += bytesread;
            }
            bytesread += info->buffer.remaining;
            mad_stream_buffer(&info->stream,info->buffer.input,bytesread);
            if (info->stream.buffer==NULL) {
                // check sync bits
                if (bytes[0] != 0xff || (bytes[1]&(3<<5)) != (3<<5)) {
                    trace ("mpgmad: read didn't start at frame boundary!\ncmp3_scan_stream is broken\n");
                }
                else {
                    trace ("mpgmad: streambuffer=NULL\n");
                }
            }
        }
        info->stream.error=0;

        // decode next frame
        if(mad_frame_decode(&info->frame,&info->stream))
        {
            if(MAD_RECOVERABLE(info->stream.error))
            {
                if(info->stream.error!=MAD_ERROR_LOSTSYNC) {
//                    printf ("mpgmad: recoverable frame level error (%s)\n", MadErrorString(&info->stream));
                }
                if (info->buffer.lead_in_frames > 0) {
                    info->buffer.lead_in_frames--;
                }
                continue;
            }
            else {
                if(info->stream.error==MAD_ERROR_BUFLEN) {
//                    printf ("mpgmad: recoverable frame level error (%s)\n", MadErrorString(&info->stream));
                    continue;
                }
                else
                {
//                    printf ("mpgmad: unrecoverable frame level error (%s).\n", MadErrorString(&info->stream));
                    return -1; // fatal error
                }
            }
        }
        mad_synth_frame(&info->synth,&info->frame);
        if (info->buffer.lead_in_frames > 0) {
            info->buffer.lead_in_frames--;
            info->buffer.decode_remaining = 0;
            continue;
        }

        info->info.fmt.samplerate = info->frame.header.samplerate;

        // synthesize single frame
        info->buffer.decode_remaining = info->synth.pcm.length;
        deadbeef->streamer_set_bitrate (info->frame.header.bitrate/1000);
        break;
    }

    return eof;
}

static int
cmp3_decode_int16 (mpgmad_info_t *info) {
    int eof = 0;
    while (!eof) {
        eof = cmp3_stream_frame (info);
        if (info->buffer.decode_remaining > 0) {
            int readsize = info->buffer.readsize;
            cmp3_decode_requested_int16 (info);
            if (info->buffer.readsize == 0) {
                return 0;
            }
        }
    }
    return 0;
}

static void
cmp3_free (DB_fileinfo_t *_info) {
    mpgmad_info_t *info = (mpgmad_info_t *)_info;
    if (info->buffer.it) {
        deadbeef->pl_item_unref (info->buffer.it);
    }
    if (info->buffer.file) {
        deadbeef->fclose (info->buffer.file);
        info->buffer.file = NULL;
        info->info.file = NULL;
        mad_synth_finish (&info->synth);
        mad_frame_finish (&info->frame);
        mad_stream_finish (&info->stream);
    }
    free (info);
}

static int
cmp3_read (DB_fileinfo_t *_info, char *bytes, int size) {
#if WRITE_DUMP
    if (!out) {
        out = fopen ("out.raw", "w+b");
    }
#endif
    int samplesize = _info->fmt.channels * _info->fmt.bps / 8;
    mpgmad_info_t *info = (mpgmad_info_t *)_info;
    if (info->buffer.duration >= 0 && !info->buffer.file->vfs->is_streaming ()) {
        int curr = info->buffer.currentsample;
        //printf ("curr: %d -> end %d, padding: %d\n", curr, info->buffer.endsample, info->buffer.padding);
        if (size / samplesize + curr > info->buffer.endsample) {
            size = (info->buffer.endsample - curr + 1) * samplesize;
            trace ("\033[0;32mmp3: size truncated to %d bytes (%d samples), cursample=%d, endsample=%d\033[37;0m\n", size, info->buffer.endsample - curr + 1, curr, info->buffer.endsample);
            if (size <= 0) {
                return 0;
            }
        }
    }
    int initsize = size;
    info->buffer.readsize = size;
    info->buffer.out = bytes;
    cmp3_decode_int16 (info);
    info->buffer.currentsample += (size - info->buffer.readsize) / samplesize;
    _info->readpos = (float)(info->buffer.currentsample - info->buffer.startsample) / info->buffer.samplerate;
#if WRITE_DUMP
    if (size - info->buffer.readsize > 0) {
        fwrite (bytes, 1, size - info->buffer.readsize, out);
    }
#endif
//    if (initsize-info->buffer.readsize != size) {
//        printf ("\033[0;31meof at sample %d\033[37;0m\n", info->buffer.currentsample);
//    }
    return initsize - info->buffer.readsize;
}

static int
cmp3_seek_sample (DB_fileinfo_t *_info, int sample) {
    mpgmad_info_t *info = (mpgmad_info_t *)_info;
    if (!info->buffer.file) {
        return -1;
    }

// {{{ handle net streaming case
    if (info->buffer.file->vfs->is_streaming ()) {
        if (info->buffer.totalsamples > 0 && info->buffer.avg_samples_per_frame > 0 && info->buffer.avg_packetlength > 0) { // that means seekable remote stream, like podcast
            trace ("seeking is possible!\n");
            // get length excluding id3v2
            int64_t l = deadbeef->fgetlength (info->buffer.file) - info->buffer.startoffset - info->buffer.endoffset;
            
            int r;

            // seek to beginning of the frame
            int64_t frm = sample / info->buffer.avg_samples_per_frame;
            r = deadbeef->fseek (info->buffer.file, frm * info->buffer.avg_packetlength + info->buffer.startoffset, SEEK_SET);

//            l = l * sample / buffer.totalsamples;
//            r = deadbeef->fseek (buffer.file, l, SEEK_SET);

            if (!r) {
                info->buffer.skipsamples = sample - frm * info->buffer.avg_samples_per_frame;

                info->buffer.currentsample = sample;
                _info->readpos = (float)(info->buffer.currentsample - info->buffer.startsample) / info->buffer.samplerate;

                // reset mad
                mad_synth_finish (&info->synth);
                mad_frame_finish (&info->frame);
                mad_stream_finish (&info->stream);
                info->buffer.remaining = 0;
                info->buffer.decode_remaining = 0;
                mad_stream_init(&info->stream);
                mad_stream_options (&info->stream, MAD_OPTION_IGNORECRC);
                mad_frame_init(&info->frame);
                mad_synth_init(&info->synth);

                return 0;
            }
            trace ("seek failed!\n");
            return -1;
        }
        trace ("seek is impossible (avg_samples_per_frame=%d, avg_packetlength=%f)!\n", info->buffer.avg_samples_per_frame, info->buffer.avg_packetlength);
        return 0;
    }
// }}}

    sample += info->buffer.startsample;
    if (sample > info->buffer.endsample) {
        trace ("seek sample %d is beyond end of track (%d)\n", sample, info->buffer.endsample);
        return -1; // eof
    }
    // restart file, and load until we hit required pos
    deadbeef->fseek (info->buffer.file, info->buffer.startoffset, SEEK_SET);
    mad_synth_finish (&info->synth);
    mad_frame_finish (&info->frame);
    mad_stream_finish (&info->stream);
    info->buffer.remaining = 0;
    info->buffer.readsize = 0;
    info->buffer.decode_remaining = 0;
	mad_stream_init(&info->stream);
	mad_stream_options (&info->stream, MAD_OPTION_IGNORECRC);
	mad_frame_init(&info->frame);
	mad_synth_init(&info->synth);

//    struct timeval tm1;
//    gettimeofday (&tm1, NULL);
    if (cmp3_seek_stream (_info, sample) == -1) {
        trace ("failed to seek to sample %d\n", sample);
        _info->readpos = 0;
        return -1;
    }
//    struct timeval tm2;
//    gettimeofday (&tm2, NULL);
//    int ms = (tm2.tv_sec*1000+tm2.tv_usec/1000) - (tm1.tv_sec*1000+tm1.tv_usec/1000);
//    printf ("cmp3_scan_stream took %d ms\n", ms);
	trace ("seeked to %d\n", info->buffer.currentsample);
    _info->readpos = (float)(info->buffer.currentsample - info->buffer.startsample) / info->buffer.samplerate;
    return 0;
}

static int
cmp3_seek (DB_fileinfo_t *_info, float time) {
    mpgmad_info_t *info = (mpgmad_info_t *)_info;
    int sample = time * info->buffer.samplerate;
    return cmp3_seek_sample (_info, sample);
}

static DB_playItem_t *
cmp3_insert (ddb_playlist_t *plt, DB_playItem_t *after, const char *fname) {
    trace ("cmp3_insert %s\n", fname);
    DB_FILE *fp = deadbeef->fopen (fname);
    if (!fp) {
        trace ("failed to open file %s\n", fname);
        return NULL;
    }
    if (fp->vfs->is_streaming ()) {
        DB_playItem_t *it = deadbeef->pl_item_alloc_init (fname, plugin.plugin.id);
        deadbeef->fclose (fp);
        deadbeef->pl_add_meta (it, "title", NULL);
        deadbeef->plt_set_item_duration (plt, it, -1);
        after = deadbeef->plt_insert_item (plt, after, it);
        deadbeef->pl_item_unref (it);
        return after;
    }
    buffer_t buffer;
    memset (&buffer, 0, sizeof (buffer));
    buffer.file = fp;
    int skip = deadbeef->junk_get_leading_size (buffer.file);
    if (skip > 0) {
        trace ("mpgmad: skipping %d bytes (tag)\n", skip);
        deadbeef->fseek(buffer.file, skip, SEEK_SET);
    }
    // calc approx. mp3 duration 
    int res = cmp3_scan_stream (&buffer, 0);
    if (res < 0) {
        trace ("mpgmad: cmp3_scan_stream returned error\n");
        deadbeef->fclose (fp);
        return NULL;
    }

    DB_playItem_t *it = deadbeef->pl_item_alloc_init (fname, plugin.plugin.id);

    deadbeef->rewind (fp);
    // reset tags
    uint32_t f = deadbeef->pl_get_item_flags (it);
    f &= ~DDB_TAG_MASK;
    deadbeef->pl_set_item_flags (it, f);
    /*int apeerr = */deadbeef->junk_apev2_read (it, fp);
    /*int v2err = */deadbeef->junk_id3v2_read (it, fp);
    /*int v1err = */deadbeef->junk_id3v1_read (it, fp);
    deadbeef->pl_set_meta_int (it, ":MP3_DELAY", buffer.delay);
    deadbeef->pl_set_meta_int (it, ":MP3_PADDING", buffer.padding);

    buffer.it = it;
    cmp3_set_extra_properties (&buffer, 0);

    deadbeef->plt_set_item_duration (plt, it, buffer.duration);
    deadbeef->fclose (fp);

    deadbeef->pl_lock ();
    {
        const char *cuesheet = deadbeef->pl_find_meta (it, "cuesheet");
        if (cuesheet) {
            DB_playItem_t *last = deadbeef->plt_insert_cue_from_buffer (plt, after, it, cuesheet, strlen (cuesheet), buffer.totalsamples-buffer.delay-buffer.padding, buffer.samplerate);
            if (last) {
                deadbeef->pl_item_unref (it);
                deadbeef->pl_item_unref (last);
                deadbeef->pl_unlock ();
                return last;
            }
        }
    }
    deadbeef->pl_unlock ();


    // FIXME! bad numsamples passed to cue
    DB_playItem_t *cue_after = deadbeef->plt_insert_cue (plt, after, it, buffer.totalsamples-buffer.delay-buffer.padding, buffer.samplerate);
    if (cue_after) {
        deadbeef->pl_item_unref (it);
        deadbeef->pl_item_unref (cue_after);
        return cue_after;
    }

    after = deadbeef->plt_insert_item (plt, after, it);
    deadbeef->pl_item_unref (it);
    return after;
}

int
cmp3_read_metadata (DB_playItem_t *it) {
    deadbeef->pl_lock ();
    DB_FILE *fp = deadbeef->fopen (deadbeef->pl_find_meta (it, ":URI"));
    deadbeef->pl_unlock ();
    if (!fp) {
        return -1;
    }
    deadbeef->pl_delete_all_meta (it);
    /*int apeerr = */deadbeef->junk_apev2_read (it, fp);
    /*int v2err = */deadbeef->junk_id3v2_read (it, fp);
    /*int v1err = */deadbeef->junk_id3v1_read (it, fp);
    deadbeef->pl_add_meta (it, "title", NULL);
    deadbeef->fclose (fp);
    return 0;
}

int
cmp3_write_metadata (DB_playItem_t *it) {
    // get options

    int strip_id3v2 = deadbeef->conf_get_int ("mp3.strip_id3v2", 0);
    int strip_id3v1 = deadbeef->conf_get_int ("mp3.strip_id3v1", 0);
    int strip_apev2 = deadbeef->conf_get_int ("mp3.strip_apev2", 0);
    int write_id3v2 = deadbeef->conf_get_int ("mp3.write_id3v2", 1);
    int write_id3v1 = deadbeef->conf_get_int ("mp3.write_id3v1", 1);
    int write_apev2 = deadbeef->conf_get_int ("mp3.write_apev2", 0);

    uint32_t junk_flags = 0;
    if (strip_id3v2) {
        junk_flags |= JUNK_STRIP_ID3V2;
    }
    if (strip_id3v1) {
        junk_flags |= JUNK_STRIP_ID3V1;
    }
    if (strip_apev2) {
        junk_flags |= JUNK_STRIP_APEV2;
    }
    if (write_id3v2) {
        junk_flags |= JUNK_WRITE_ID3V2;
    }
    if (write_id3v1) {
        junk_flags |= JUNK_WRITE_ID3V1;
    }
    if (write_apev2) {
        junk_flags |= JUNK_WRITE_APEV2;
    }

    int id3v2_version = deadbeef->conf_get_int ("mp3.id3v2_version", 3);
    if (id3v2_version != 3 && id3v2_version != 4) {
        id3v2_version = 3;
    }
    char id3v1_encoding[50];
    deadbeef->conf_get_str ("mp3.id3v1_encoding", "iso8859-1", id3v1_encoding, sizeof (id3v1_encoding));
    return deadbeef->junk_rewrite_tags (it, junk_flags, id3v2_version, id3v1_encoding);
}

static const char *exts[] = {
	"mp1", "mp2", "mp3", "mpga", NULL
};

static const char settings_dlg[] =
    "property \"Disable gapless playback (faster scanning)\" checkbox mp3.disable_gapless 0;\n"
;

// define plugin interface
static DB_decoder_t plugin = {
    .plugin.api_vmajor = 1,
    .plugin.api_vminor = 0,
    .plugin.version_major = 1,
    .plugin.version_minor = 0,
    .plugin.type = DB_PLUGIN_DECODER,
    .plugin.id = "stdmpg",
    .plugin.name = "MPEG decoder",
    .plugin.descr = "MPEG v1/2 layer1/2/3 decoder based on libmad",
    .plugin.copyright = 
        "MPEG decoder plugin based on libmad\n"
        "Copyright (C) 2009-2014 Alexey Yakovenko\n"
        "\n"
        "This software is provided 'as-is', without any express or implied\n"
        "warranty.  In no event will the authors be held liable for any damages\n"
        "arising from the use of this software.\n"
        "\n"
        "Permission is granted to anyone to use this software for any purpose,\n"
        "including commercial applications, and to alter it and redistribute it\n"
        "freely, subject to the following restrictions:\n"
        "\n"
        "1. The origin of this software must not be misrepresented; you must not\n"
        " claim that you wrote the original software. If you use this software\n"
        " in a product, an acknowledgment in the product documentation would be\n"
        " appreciated but is not required.\n"
        "\n"
        "2. Altered source versions must be plainly marked as such, and must not be\n"
        " misrepresented as being the original software.\n"
        "\n"
        "3. This notice may not be removed or altered from any source distribution.\n"
    ,
    .plugin.website = "http://deadbeef.sf.net",
    .plugin.configdialog = settings_dlg,
    .open = cmp3_open,
    .init = cmp3_init,
    .free = cmp3_free,
    .read = cmp3_read,
    .seek = cmp3_seek,
    .seek_sample = cmp3_seek_sample,
    .insert = cmp3_insert,
    .read_metadata = cmp3_read_metadata,
    .write_metadata = cmp3_write_metadata,
    .exts = exts,
};

DB_plugin_t *
mpgmad_load (DB_functions_t *api) {
    deadbeef = api;
    return DB_PLUGIN (&plugin);
}
