#include "kernel.h"
#include "fd.h"
#include "fifo.h"
#include "kmalloc.h"
#include "ext2.h"
#include "log.h"
#include "lib/string/string.h"
#include "lib/printf/printf.h"
#include "ringbuffer.h"

bool fd_write(fd* f,uint8_t c)
{
    if(!f->write)kpanic("no write func")
    return f->write(f->data,c);
}

uint8_t fd_read(fd* f)
{
    if(!f->read)kpanic("no read func")
    return f->read(f->data);
}

bool fd_has(fd* f)
{
    if(!f->has)kpanic("no has func")
    return f->has(f->data);
}
bool fd_can_write(fd* f)
{
    if(!f->can_write)kpanic("no has func")
    return f->can_write(f->data);
}

bool fd_eof(fd* f)
{
    if(!f->eof)kpanic("no eof func")
    return f->eof(f->data);
}

bool fd_close(fd* f)
{
    if(!f->close)kpanic("no close func")
    return f->close(f->data);
}

fd fd_dupl(fd* f)
{
    if(!f->dupl)kpanic("no dupl func")
    return f->dupl(f);
}

static fd default_dupl(fd *f)
{
    return *f;
}
void default_close(void* x)
{
    // nothin
}

//----
void* ext2_init(char *path)
{
    uint32_t *data=kballoc(1);
    uint32_t inode= ext2_filename_to_inode(VMEM_EXT2_RAMIMAGE,path); 
    data[0]=inode;// inode
    data[1]=0; //pos
    return data;
}

void ext2_write(void* x,uint8_t b)
{
    kpanic("not impl");
}

uint8_t ext2_read(uint32_t* data)
{
    char c;
    ext2_read_inode(VMEM_EXT2_RAMIMAGE,data[0],&c,&data[1],1);
    return c;
}

bool ext2_has(uint32_t* data)
{
    return 1;
}

bool ext2_eof(uint32_t* data)
{
    uint32_t save=data[1];
    uint32_t c=ext2_read_inode(VMEM_EXT2_RAMIMAGE,data[0],&c,&data[1],1);
    data[1]=save;
    return (c==0);
}

void ext2_close(void* x)
{
    kbfree(x);
}

uint8_t sysfs_get(uint32_t *data)
{
    return ringbuffer_get(data);
}

void sysfs_write(void* x,uint8_t b)
{
    uint32_t **pp=x+sizeof(ringbuffer);
    void (*p)(uint32_t v)=*pp;

    uint32_t *val=x+sizeof(ringbuffer)+4;
    val[val[0]]=b;
    if(val[0]==4) // 4bytes / 32bit
    {
	val[0]=1;
	p(val[1]+256*val[2]+256*256*val[3]+256*256*256*val[4]);
    }
    val[0]+=1;
}

bool sysfs_has(uint32_t *data)
{
    return true;
}

bool sysfs_eof(uint32_t *data)
{
    return !ringbuffer_has(data);
}

void sysfs_close(uint32_t *data)
{
    ringbuffer_free(data); // free ringbuffer buffer
    kbfree(data); // free memory holding ringbuffer information
}

void pipe_r_close(uint8_t *data)
{
    uint8_t *mem=data+sizeof(ringbuffer);
    *mem-=1;
    klog("closing read end of pipe at 0x%08x, ref count=%d",mem,*mem);
    /*
    if(*mem==0) // TODO : check other end too! and close on w_close
    {
	ringbuffer *r=data;
	ringbuffer_free(data); // free ringbuffer buffer
	kbfree(data); // free memory holding ringbuffer information
    }
    */
}

void pipe_w_close(uint8_t *data)
{
    uint8_t *mem=data+sizeof(ringbuffer);
    mem+=4;
    *mem-=1;
    klog("closing write end of pipe at 0x%08x, ref count=%d",mem,*mem);
}

static fd pipe_r_dupl(fd *f)
{
    uint8_t *mem=f->data+sizeof(ringbuffer);
    *mem+=1;
    klog("duplicating read end of pipe at 0x%08x, ref count=%d",mem,*mem);
    return *f;
}

static fd pipe_w_dupl(fd *f)
{
    uint8_t *mem=f->data+sizeof(ringbuffer);
    mem+=4;
    *mem+=1;
    klog("duplicating write end of pipe at 0x%08x, ref count=%d",mem,*mem);
    return *f;
}

void get_sysfs_data(ringbuffer *r,char *format_string, ...)
{
    char buf[256];
    va_list va;
    va_start(va,format_string);
    tfp_vsprintf(buf,format_string,va);
    va_end(va);

    for(int i=0;i<strlen(buf);i++)
	ringbuffer_put(r,buf[i]);

    ringbuffer_put(r,'\n');
}

bool fifo_eof(uint32_t* data)
{
    return false;
}


uint8_t pipe_get(uint32_t *data)
{
    return ringbuffer_get(data);
}

void pipe_put(void* data,uint8_t b)
{
    ringbuffer_put(data,b);
}

bool pipe_has(uint32_t *data)
{
    return ringbuffer_has(data);
}
bool pipe_can_write(uint32_t *data)
{
    return !ringbuffer_full(data);
}

bool pipe_eof(uint8_t *data)
{

    uint8_t *mem=data+sizeof(ringbuffer);
    mem+=4;
    //we assume EOF if there is no data anymore AND no writers!
    return (!ringbuffer_has(data))&&(*mem==0);
}


///// 

int fds_from_pipe(fd pipefds[2])
{
    fd read;
    fd wrt;

    read.type=FD_TYPE_PIPE;
    wrt.type=FD_TYPE_PIPE;

    uint8_t *mem=kballoc(1);

    read.data=mem;
    wrt.data=mem;

    ringbuffer r=ringbuffer_init(1);

    memcpy(mem,&r,sizeof(ringbuffer));
    mem+=sizeof(ringbuffer);
    *mem=1;
    mem+=4;
    *mem=1;
    
    read.can_write=0;

    read.read=pipe_get;
    wrt.read=0;

    wrt.write=pipe_put;
    read.write=0;

    read.has=pipe_has;
    wrt.has=0;

    read.eof=pipe_eof;
    wrt.eof=0;
    wrt.can_write=pipe_can_write;

    read.close=pipe_r_close;
    wrt.close=pipe_w_close;

    read.dupl=pipe_r_dupl;
    wrt.dupl=pipe_w_dupl;

    pipefds[0]=read;
    pipefds[1]=wrt;
    
    return 0;
}

fd fd_from_path(char* path)
{
    fd f;
    f.type=FD_TYPE_EXT2_FILE;
    f.data=ext2_init(path);
    f.read=ext2_read;
    f.write=ext2_write;
    f.close=ext2_close;
    f.eof=ext2_eof;
    f.has=ext2_has;
    f.dupl=default_dupl;
    return f;
}

fd fd_from_sysfs(void(*g)(ringbuffer *r,void (*f)(ringbuffer *r,char *fmt, ...)),void (*h)(uint32_t in))
{
    fd f;
    f.type=FD_TYPE_SYSFS;
    f.data=kballoc(1);

    uint32_t **pp=f.data+sizeof(ringbuffer); 
    *pp=h; 

    uint32_t *val=f.data+sizeof(ringbuffer)+4;
    val[0]=1; // waiting for first byte of the 32bit value

    ringbuffer r=ringbuffer_init(1);

    g(&r,get_sysfs_data);
    memcpy(f.data,&r,sizeof(ringbuffer));

    f.read=sysfs_get;
    f.write=sysfs_write;
    f.close=sysfs_close;
    f.has=sysfs_has;
    f.eof=sysfs_eof;
    f.dupl=default_dupl;
    f.close=default_close;
    return f;
}

bool fifo_can_write(fifo *f)
{
    return !(f->full(f->data));
}

fd fd_from_fifo(fifo* fif)
{
    fd f;
    f.type=FD_TYPE_FIFO;
    f.data=fif;
    f.read=fifo_get;
    f.write=fifo_put;
    f.eof=fifo_eof;
    f.has=fifo_has;
    f.dupl=default_dupl;
    f.close=default_close;
    f.can_write=fifo_can_write;
    return f;
}