/*!@file
  \brief   IR Memory Implementation
  \details Intermediary memory management
  \author  Jordan Lavatai
  \date    Aug 2016
  ----------------------------------------------------------------------------*/
/* Standard */
#include <stdlib.h> //exit, malloc
#include <stdio.h>  //print
#include <stdarg.h> //va_args
#include <stdint.h> //uint64_t
#include <string.h> //memset, str*
/* Unicode */
#include <unistd.h>   //u8_* functions
#include <unitypes.h> //uint8_t as a char
#include <unistr.h>   //u32_cpy
/* Local */
#include "apc.h"
#include "ir.h"
/* Public */
int      ir_init(void);
void     ir_quit(void);
int      ir_linker(void);
int      ir_condenser(void);
/* Memory allocation structures */
enum dtype { FSDAT, MSDAT, ADAT, LDAT, FBDAT };
struct pagenode_t;
struct pagenode_header_t {
  struct pagenode_t* next;
  char*              head;
};
struct pagenode_t {
  struct pagenode_header_t header;
  char                     root[];
};
struct pagelist_t {
  struct pagenode_t* root, * head;
  size_t             pagesize;
};
struct ir_namelist_t;
struct ir_namelist_t
{ struct ir_namelist_t* nextsib;
  uint8_t*              name;
};
struct ir_classld_t
{ struct ir_class_t*    root_class;
  struct ir_namelist_t* namelist, * namelist_head;
};
struct ir_setld_t
{ struct ir_classld_t*  classld;
  long long             ref;
  struct ir_namelist_t* namelist, * namelist_head;
};
/* Set data mem */
struct ir_setdata_header_t
{ enum dtype          type;
  uint8_t*            src_filename, * data_name;
  union ir_setdata_t* nextsib;
};
struct ir_frameinfo_t
{ int facing, w, h; };
struct ir_framedata_t
{ struct ir_setdata_header_t header;
  struct ir_frameinfo_t      frameinfo;
};
struct ir_framebox_t
{ struct ir_setdata_header_t header;
  struct ir_framedata_t      framesheets[FACING_MAX];
  struct ir_framedata_t      mapsheets[FACING_MAX];
};
struct ir_simplex_t { struct ir_setdata_header_t header; };
struct ir_link_t
{ struct ir_setdata_header_t header;
  struct ir_classld_t*       classld;
  struct ir_setld_t*         setld;
  enum ltype                 type;
};
union ir_setdata_t
{ struct ir_setdata_header_t  header;
  struct ir_framebox_t        framebox;
  struct ir_framedata_t       framesheet;
  struct ir_framedata_t       mapsheet;
  struct ir_simplex_t         audio;
  struct ir_link_t            link;
};
struct ir_class_t
{ struct ir_class_t* nextchild, * nextsib;
  struct ir_set_t*   root_set;
  uint8_t*           name;
};
struct ir_set_t
{ struct ir_set_t*      nextchild, * nextsib;
  struct ir_class_t*    class;
  long long             ref;
  uint8_t*              name;
  struct ir_framebox_t* frameboxes;
  struct ir_simplex_t*  audio;
  struct ir_link_t*     links;
};
/* Functions */
static inline
int                   init_pagelist(struct pagelist_t*,size_t);
static inline
struct ir_framebox_t* ir_set_add_framebox(struct ir_set_t*,const uint8_t*);
static
void                  ir_free_pagenodes(struct pagenode_t*);
static inline
int                   bytes_identical(const uint8_t*,const uint8_t*);
static
void*                 stack_alloc(size_t);
static
uint8_t*              name_alloc(const uint8_t*);
static inline
union ir_setdata_t*   ir_framedata (enum dtype,const uint8_t*,apc_facing,int,int);
/* Function-Like Macros */
#define do_warn() do {				\
  } while (0)
#define wprint(str) do {			\
    fprintf(stderr, str);			\
    do_warn();					\
  } while (0)
#define wprintf(fmt,...) do {			\
    fprintf(stderr, fmt, __VA_ARGS__);		\
    do_warn();					\
  } while (0)
#define do_error() do {				\
    exit(-1);					\
  } while (0)
#define eprint(str) do {			\
    fprintf(stderr, str);			\
    do_error();					\
  } while (0)
#define eprintf(fmt,...) do {			\
    fprintf(stderr, fmt, __VA_ARGS__);		\
    do_error();					\
  } while (0)
#define struct_alloc(_T) ((struct _T*) stack_alloc(sizeof(struct _T)))
#define DATA_PAGESIZE   (sys_pagesize)
#define NAME_PAGESIZE   (APC_NAME_MAX * 1024)
#define PL_HEADERSIZE   (sizeof(struct pagenode_header_t))
#define PL_HEADSIZE(_PL) (_PL.head->header.head - _PL.head->root)
#define PL_HEADMEM(_PL)  (_PL.pagesize - PL_HEADERSIZE - PL_HEADSIZE(_PL))
/* Memory */
extern //apc.c
long sys_pagesize;
static
struct pagelist_t datapages, namepages;
static
struct ir_class_t root_class = { .name = (uint8_t*)"." };

/* Init */
int ir_init
( void )
{ if (init_pagelist(&datapages, (size_t)DATA_PAGESIZE))
    eprint("Memory allocation error\n");
  if (init_pagelist(&namepages, (size_t)NAME_PAGESIZE))
    eprint("Memory allocation error\n");
  return 0;
}

static inline
int init_pagelist
( struct pagelist_t* pl,
  size_t size
)
{ pl->pagesize = size;
  pl->root = (struct pagenode_t*) calloc(size,1);
  if (pl->root == NULL)
    return -1;
  pl->root->header.head = pl->root->root;
  pl->head = pl->root;
  return 0;
}

/* Quit/Cleanup
   Recursively clean pagenode linked list
*/
void ir_quit
( void )
{ ir_free_pagenodes(datapages.root);
  ir_free_pagenodes(namepages.root);
}

static
void ir_free_pagenodes
( struct pagenode_t* pagenode )
{ if (pagenode->header.next != NULL)
    ir_free_pagenodes(pagenode->header.next);
  free(pagenode);
}

/* Link
*/
int ir_linker
( void )
{ return 0; }

/* Condense
*/
int ir_condenser
( void )
{ return 0; }

/* Return a pointer to the root class */
struct ir_class_t* ir_class_root
( void )
{ return &root_class; }

/* Add a subclass to a class
   Attempts to create a new subclass in the provided class, returning
   the class if it already exists
*/
struct ir_class_t* ir_class_addchild
( struct ir_class_t* class,
  const uint8_t*     name
)
{ struct ir_class_t* iter;
  printf("Class %s, addchild %s\n", class->name, name);
  if (class->nextchild == NULL)
    goto alloc;
  iter = class->nextchild;
  if (iter->name == NULL)
    eprintf("Null name pointer in class %p\n", iter);
  if (name == NULL)
    eprintf("Null child added to class %s\n", iter->name);
 check:
  if (bytes_identical(iter->name, name))
    return iter;
  if (iter->nextsib != NULL)
    { iter = iter->nextsib;
      goto check;
    }
 alloc:
  iter = struct_alloc(ir_class_t);
  iter->nextsib = class->nextchild;
  iter->name = name_alloc(name);
  return class->nextchild = iter;
}

/* Add a set to a class
   Attempts to create a new root set in the specified class, returning
   the set if it already exists
*/
struct ir_set_t* ir_class_addset
( struct ir_class_t* class,
  const uint8_t*     name
)
{ struct ir_set_t* iter;
  printf("Class %s, addset %s\n", class->name, name);
  if (class->root_set == NULL)
    goto alloc;
  iter = class->root_set;
  if (iter->name == NULL)
    eprintf("Null name pointer in class %p\n", iter);
  if (name == NULL)
    eprintf("Null set added to class %s\n", iter->name);
 check:
  if (bytes_identical(iter->name, name))
    return iter;
  if (iter->nextsib != NULL)
    { iter = iter->nextsib;
      goto check;
    }
 alloc:
  iter = struct_alloc(ir_set_t);
  iter->nextsib = class->root_set;
  iter->name = name_alloc(name);
  return class->root_set = iter;
}

/* Add a set to a set
   Attempts to create a new subset of the specified set, returning the
   child if it already exists
*/
struct ir_set_t* ir_set_addchild
( struct ir_set_t* set,
  const uint8_t*   name
)
{ struct ir_set_t* iter;
  printf("Set %s, addchild %s\n", set->name, name);
  if (set->nextchild == NULL)
    goto alloc;
  iter = set->nextchild;
  if (iter->name == NULL)
    eprintf("Null name pointer in set %p\n", iter);
  if (name == NULL)
    eprintf("Null child added to set %s\n", iter->name);
 check:
  if (bytes_identical(iter->name, name))
    return iter;
  if (iter->nextsib != NULL)
    { iter = iter->nextsib;
      goto check;
    }
 alloc:
  iter = struct_alloc(ir_set_t);
  iter->nextsib = set->nextchild;
  iter->name = name_alloc(name);
  return set->nextchild = iter;
}

/* Add a framebox to a set
   Attempts to create a new framebox of the specified set, returning
   the framebox if it already exists
*/
static inline
struct ir_framebox_t* ir_set_add_framebox
( struct ir_set_t* set,
  const uint8_t*   name
)
{ struct ir_framebox_t* iter;
  if (set->frameboxes == NULL)
    goto alloc;
  iter = set->frameboxes;
 check:
  if (bytes_identical(iter->header.data_name, name))
    return iter;
  if (iter->header.nextsib != NULL)
    { iter = (struct ir_framebox_t*) iter->header.nextsib;
      goto check;
    }
 alloc:
  iter = struct_alloc(ir_framebox_t);
  iter->header.nextsib = (union ir_setdata_t*) set->frameboxes;
  iter->header.data_name = name_alloc(name);
  return set->frameboxes = iter;
}

/* Match two null-terminated bytestrings
   Return 1 if the two bytestrings are identical, else 0
*/
static inline
int bytes_identical
( const uint8_t* stra,
  const uint8_t* strb
)
{ int ca, cb;
  do {
    ca = *stra++;
    cb = *strb++;
  } while (ca && ca != '_' && ca == cb);
  return (ca == cb);
}

/* Assign Setdata to Set

 */
void ir_set_assign_data
( struct ir_set_t*      set,
  union  ir_setdata_t*  setdata
)
{ struct ir_framebox_t* framebox;
  struct ir_simplex_t*  simplex;
  switch (setdata->header.type)
    { case FSDAT:
	framebox = ir_set_add_framebox(set, setdata->header.data_name);
	if (framebox->framesheets[setdata->framesheet.frameinfo.facing].header.data_name != NULL)
	  wprintf("Duplicate framesheet [%i] %s\n",
		  setdata->framesheet.frameinfo.facing, setdata->header.data_name);
	framebox->framesheets[setdata->framesheet.frameinfo.facing] = setdata->framesheet;
	break;
      case MSDAT:
	framebox = ir_set_add_framebox(set, setdata->header.data_name);
	if (framebox->mapsheets[setdata->mapsheet.frameinfo.facing].header.data_name != NULL)
	  wprintf("Duplicate mapsheet [%i] %s\n",
		  setdata->mapsheet.frameinfo.facing, setdata->header.data_name);
	framebox->mapsheets[setdata->mapsheet.frameinfo.facing] = setdata->mapsheet;
	break;
      case ADAT:
	if (set->audio == NULL)
	  { set->audio = (struct ir_simplex_t*) setdata;
	    return;
	  }
	simplex = set->audio;
	while (simplex->header.nextsib != NULL)
	  if (bytes_identical(simplex->header.data_name, setdata->header.data_name))
	    { wprintf("Duplicate audio %s\n", setdata->header.data_name);
	      *simplex = setdata->audio;
	      //setdata is now a pointer to redundant, unused memory.
	      return;
	    }
	  else
	    simplex = (struct ir_simplex_t*) simplex->header.nextsib;
	setdata->audio.header.nextsib = (union ir_setdata_t*) set->audio;
        set->audio = (struct ir_simplex_t*) setdata;
	break;
      case LDAT:
	setdata->link.header.nextsib = (union ir_setdata_t*) set->links;
	set->links = (struct ir_link_t*) setdata;
	break;
      default:
	fprintf(stderr, "Unknown setdata type %x\n", setdata->header.type);
	exit(-1);
    }
}

void ir_set_assign_ref
( struct ir_set_t* set,
  long long        ref
)
{ if (set->ref != 0)
    wprintf("Ref override: 0x%lx -> 0x%lx for set %s\n",
	    (long unsigned) set->ref, (long unsigned) ref, set->name);
  set->ref = ref;
  //TODO: reflist_add(set);
}

void ir_data_assign_path
( union ir_setdata_t* setdata,
  const uint8_t*      path
)
{ if (path == NULL)
    eprintf("Null path in data %s\n", setdata->header.data_name);
  if (setdata->header.src_filename != NULL)
    wprintf("Path override: %s -> %s for setdata %s\n",
	    setdata->header.src_filename, path, setdata->header.data_name);
  setdata->header.src_filename = name_alloc(path);
}

union ir_setdata_t* ir_framesheet
( const uint8_t* name,
  apc_facing     d,
  int            width,
  int            height
)
{ return ir_framedata(FSDAT, name, d, width, height); }

union ir_setdata_t* ir_mapsheet
( const uint8_t* name,
  apc_facing     d,
  int            width,
  int            height
)
{ return ir_framedata(MSDAT, name, d, width, height); }

static inline
union ir_setdata_t* ir_framedata
( enum dtype     type,
  const uint8_t* name,
  apc_facing     d,
  int            width,
  int            height
)
{ struct ir_framedata_t* framedata = struct_alloc(ir_framedata_t);
  if (name == NULL)
    eprint("Null name in set allocation\n");
  framedata->header.type = type;
  framedata->header.data_name = name_alloc(name);
  framedata->frameinfo.facing = d;
  framedata->frameinfo.w = width;
  framedata->frameinfo.h = height;
  return (union ir_setdata_t*) framedata;
}

union ir_setdata_t* ir_audio
( const uint8_t* name )
{ struct ir_simplex_t* audio = struct_alloc(ir_simplex_t);
  if (name == NULL)
    eprint("Null audio\n");
  audio->header.type = ADAT;
  audio->header.data_name = name_alloc(name);
  return (union ir_setdata_t*) audio;
}


/* Create classld that points to a class */
struct ir_classld_t* ir_classld_from_class
( struct ir_class_t* class )
{ struct ir_classld_t* classld;
  if (class == NULL)
    eprint("Null class in classld\n");
  classld = struct_alloc(ir_classld_t);
  classld->root_class = class;
  return classld;
}

struct ir_setld_t* ir_setld_from_ref
( long long ref )
{ struct ir_setld_t* setld;
  setld = struct_alloc(ir_setld_t);
  setld->ref = ref;
  return setld;
}

struct ir_setld_t* ir_setld_from_classld
( struct ir_classld_t* classld,
  const uint8_t*       name
)
{ struct ir_setld_t* setld;
  setld = struct_alloc(ir_setld_t);
  setld->namelist = struct_alloc(ir_namelist_t);
  setld->namelist_head = setld->namelist;
  setld->namelist_head->name = name_alloc(name);
  setld->classld = classld;
  return setld; 
}

struct ir_setld_t* ir_setld_addchild
( struct ir_setld_t* setld,
  const uint8_t*     name
)
{ if (setld->namelist == NULL)
    { setld->namelist = struct_alloc(ir_namelist_t);
      setld->namelist_head = setld->namelist;
    }
  else
    { setld->namelist_head->nextsib = struct_alloc(ir_namelist_t);
      setld->namelist_head = setld->namelist_head->nextsib;
    }
  setld->namelist_head->name = name_alloc(name);
  return setld;
}

union ir_setdata_t* ir_link
( enum ltype         link_type,
  struct ir_setld_t* setld,
  const uint8_t*     name
)
{ struct ir_link_t* link;
  link = struct_alloc(ir_link_t);
  link->header.type = LDAT;
  link->type = link_type; 
  link->classld = setld->classld;
  link->setld = setld;
  if (link_type != OLINK && name != NULL)
    link->header.data_name = name_alloc(name);
  return (union ir_setdata_t*) link;
}


static
void* stack_alloc
( size_t bytes )
{ if (!bytes) //valid behavior to attain current head
    return datapages.head->header.head;
  if (PL_HEADMEM(datapages) < bytes) 
    { datapages.head->header.next = (struct pagenode_t*) calloc(datapages.pagesize,1);
      if (datapages.head->header.next == NULL)
	eprint("Memory allocation error \n");
      datapages.head = datapages.head->header.next; 
      datapages.head->header.head = datapages.head->root;
    }
  datapages.head->header.head += bytes;
  return (void*) datapages.head->header.head - bytes;
}

static
uint8_t* name_alloc
( const uint8_t* name_src )
{ const uint8_t* iter;
  uint8_t*       name;
  int            head_mem;
 copy:
  name = (uint8_t*)namepages.head->header.head;
  iter = name_src;
  for (head_mem = PL_HEADMEM(namepages); *iter && *iter != '_' && head_mem; head_mem--)
    *(namepages.head->header.head)++ = *iter++;
  if (head_mem == 0) //not enough room
    { namepages.head->header.next = (struct pagenode_t*) calloc(namepages.pagesize,1);
      if (namepages.head->header.next == NULL)
	eprint("Memory allocation error\n");
      namepages.head = namepages.head->header.next;
      namepages.head->header.head = namepages.head->root;
      goto copy;
    }
  *(namepages.head->header.head)++ = '\0';
  return name;
}