#include "wavPlayer.h"
#include<cstdio>

extern "C" void AS_StereoDesinterleave(void *input, void *outputL, void *outputR, u32 samples);

static void error(const char* c)
{
    fprintf(stderr, "%s\n", c);
//  exit(1);
}

void AS_SetTimer(int freq)
{
    if(freq) {
        TIMER0_DATA = 0x10000 - (0x1000000 / freq) * 2;
        TIMER0_CR = TIMER_ENABLE | TIMER_DIV_1;
        TIMER1_DATA = 0;
        TIMER1_CR = TIMER_ENABLE | TIMER_CASCADE | TIMER_DIV_1;
    } else {
        TIMER0_DATA = 0;
        TIMER0_CR = 0;
        TIMER1_DATA = 0;
        TIMER1_CR = 0;
    }
}

void wavPlayer::stop()
{
    soundKill(leftSoundID);
    soundKill(rightSoundID);
    stopped = true;
}

void wavPlayer::regenStreamAtPos(int pos, int len)
{
//  fprintf(stdout, "str %x %x\n", pos, len);

    if(len == 0) return;

    //Now, read into the buffer
    u32 left = len*channels;

    left -= fread(mainbuffer, 1, left, fh);
    while(left != 0)
    {
        fseek(fh, 0, SEEK_SET);
        left -= fread(mainbuffer, 1, left, fh);
    }

    if(channels==1)
    {
        memcpy(audiobufferLeft+pos, mainbuffer, len);
        memcpy(audiobufferRight+pos, mainbuffer, len);
    }
    else
    {
        AS_StereoDesinterleave(mainbuffer, audiobufferLeft+pos, audiobufferRight+pos, len/2);
    }
}

void wavPlayer::update()
{
    if(destroyed) return;

    //Find out how many new samples should we push to the buffer.
    int curtimer = TIMER1_DATA;

    int newdata = curtimer - prevtimer;
    if(newdata < 0)
        newdata += 65536;

    newdata *= 2; //samples are 16bit

    printf("\x1b[5;1HBUFFER:  %3d %%        ", 100-newdata*100/audiobuffer_size);

    if(newdata > audiobuffer_size) newdata = audiobuffer_size; //do noo overflow
//  if(newdata > 0x600)  newdata = 0x600;

    printf("\x1b[4;1HFRAME:  %3d %%        ", newdata*100/audiobuffer_size);

//  fprintf(stdout, "nw %x\n", newdata);

    prevtimer = curtimer;
    if(soundcursor + newdata >= audiobuffer_size) //New chunks of data are split
    {
        regenStreamAtPos(soundcursor, audiobuffer_size-soundcursor);
        int remain = newdata - (audiobuffer_size-soundcursor);
        regenStreamAtPos(0, remain);
//      iprintf("!");
    }
    else
    {
        regenStreamAtPos(soundcursor, newdata);
//      iprintf(".");
    }

    soundcursor += newdata;
    if(soundcursor >= audiobuffer_size)
        soundcursor -= audiobuffer_size;
}

wavPlayer::wavPlayer(const char* filename)
{
    int err;
    stopped = false;

    fh = fopen(filename, "rb");

    rate = 32000;
    channels = 2;

    audiobuffer_size = 8192*4;
    audiobufferLeft = new u8[audiobuffer_size];

    audiobufferRight = new u8[audiobuffer_size];
    mainbuffer_size = audiobuffer_size*channels;
    mainbuffer = new u8[mainbuffer_size];

    memset(audiobufferLeft, 0, audiobuffer_size);
    memset(audiobufferRight, 0, audiobuffer_size);
    memset(mainbuffer, 0, mainbuffer_size);
    fprintf(stderr, "main buffersize %i \n", mainbuffer_size);
    fprintf(stderr, "audio buffersize %i \n", audiobuffer_size);

    leftSoundID = soundPlaySample(audiobufferLeft, SoundFormat_16Bit, audiobuffer_size, rate, 127, 0, true, 0);
    rightSoundID = soundPlaySample(audiobufferRight, SoundFormat_16Bit, audiobuffer_size, rate, 127, 127, true, 0);
    AS_SetTimer(rate);

    soundcursor = 0;
    prevtimer = 0;

    destroyed = false;
}

wavPlayer::~wavPlayer()
{
    destroyed = true;
    fclose(fh);
    delete[] audiobufferLeft;
    delete[] audiobufferRight;
    delete[] mainbuffer;
    AS_SetTimer(0);
}


// desinterleave a stereo source (thanks to Thoduv for the code)
asm (
"@--------------------------------------------------------------------------------------\n"
"    .text                                                                              \n"
"    .arm                                                                               \n"
"                                                                                       \n"
"@ desinterleave an mp3 stereo source                                                   \n"
"@ r0 = interleaved data, r1 = left, r2 = right, r3 = len                               \n"
"                                                                                       \n"
"    .global AS_StereoDesinterleave                                                     \n"
"                                                                                       \n"
"AS_StereoDesinterleave:                                                                \n"
"    stmfd sp!, {r4-r11}                                                                \n"
"                                                                                       \n"
"_loop:                                                                                 \n"
"                                                                                       \n"
"    ldmia r0!, {r4-r12}                                                                \n"
"                                                                                       \n"
"    strh r4, [r1], #2                                                                  \n"
"    mov r4, r4, lsr #16                                                                \n"
"    strh  r4, [r2], #2                                                                 \n"
"    subs r3, #1                                                                        \n"
"    beq _done                                                                          \n"
"                                                                                       \n"
"    strh r5, [r1], #2                                                                  \n"
"    mov r5, r5, lsr #16                                                                \n"
"    strh  r5, [r2], #2                                                                 \n"
"    subs r3, #1                                                                        \n"
"    beq _done                                                                          \n"
"                                                                                       \n"
"    strh r6, [r1], #2                                                                  \n"
"    mov r6, r6, lsr #16                                                                \n"
"    strh  r6, [r2], #2                                                                 \n"
"    subs r3, #1                                                                        \n"
"    beq _done                                                                          \n"
"                                                                                       \n"
"    strh r7, [r1], #2                                                                  \n"
"    mov r7, r7, lsr #16                                                                \n"
"    strh  r7, [r2], #2                                                                 \n"
"    subs r3, #1                                                                        \n"
"    beq _done                                                                          \n"
"                                                                                       \n"
"    strh r8, [r1], #2                                                                  \n"
"    mov r8, r8, lsr #16                                                                \n"
"    strh  r8, [r2], #2                                                                 \n"
"    subs r3, #1                                                                        \n"
"    beq _done                                                                          \n"
"                                                                                       \n"
"    strh r9, [r1], #2                                                                  \n"
"    mov r9, r9, lsr #16                                                                \n"
"    strh  r9, [r2], #2                                                                 \n"
"    subs r3, #1                                                                        \n"
"    beq _done                                                                          \n"
"                                                                                       \n"
"    strh r10, [r1], #2                                                                 \n"
"    mov r10, r10, lsr #16                                                              \n"
"    strh  r10, [r2], #2                                                                \n"
"    subs r3, #1                                                                        \n"
"    beq _done                                                                          \n"
"                                                                                       \n"
"    strh r11, [r1], #2                                                                 \n"
"    mov r11, r11, lsr #16                                                              \n"
"    strh  r11, [r2], #2                                                                \n"
"    subs r3, #1                                                                        \n"
"    beq _done                                                                          \n"
"                                                                                       \n"
"    strh r12, [r1], #2                                                                 \n"
"    mov r12, r12, lsr #16                                                              \n"
"    strh  r12, [r2], #2                                                                \n"
"    subs r3, #1                                                                        \n"
"    bne _loop                                                                          \n"
"_done:                                                                                 \n"
"                                                                                       \n"
"    ldmia sp!, {r4-r11}                                                                \n"
"    bx lr                                                                              \n"
"@--------------------------------------------------------------------------------------\n"
);