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

#include "postgres.h"
#include "extern.h"

/* malloc + error check */
void *
mm_alloc(size_t size)
{
	void	   *ptr = malloc(size);

	if (ptr == NULL)
	{
		fprintf(stderr, "Out of memory\n");
		exit(OUT_OF_MEMORY);
	}

	return ptr;
}

/* strdup + error check */
char *
mm_strdup(const char *string)
{
	char	   *new = strdup(string);

	if (new == NULL)
	{
		fprintf(stderr, "Out of memory\n");
		exit(OUT_OF_MEMORY);
	}

	return new;
}

/* duplicate memberlist */
struct ECPGstruct_member *
ECPGstruct_member_dup(struct ECPGstruct_member * rm)
{
	struct ECPGstruct_member *new = NULL;

	while (rm)
	{
		struct ECPGtype *type;

		switch (rm->typ->typ)
		{
			case ECPGt_struct:
			case ECPGt_union:
				type = ECPGmake_struct_type(rm->typ->u.members, rm->typ->typ);
				break;
			case ECPGt_array:
				type = ECPGmake_array_type(ECPGmake_simple_type(rm->typ->u.element->typ, rm->typ->u.element->size), rm->typ->size);
				break;
			default:
				type = ECPGmake_simple_type(rm->typ->typ, rm->typ->size);
				break;
		}

		ECPGmake_struct_member(rm->name, type, &new);

		rm = rm->next;
	}

	return (new);
}

/* The NAME argument is copied. The type argument is preserved as a pointer. */
void
ECPGmake_struct_member(char *name, struct ECPGtype * type, struct ECPGstruct_member ** start)
{
	struct ECPGstruct_member *ptr,
			   *ne =
	(struct ECPGstruct_member *) mm_alloc(sizeof(struct ECPGstruct_member));

	ne->name = strdup(name);
	ne->typ = type;
	ne->next = NULL;

	for (ptr = *start; ptr && ptr->next; ptr = ptr->next);

	if (ptr)
		ptr->next = ne;
	else
		*start = ne;
}

struct ECPGtype *
ECPGmake_simple_type(enum ECPGttype typ, long siz)
{
	struct ECPGtype *ne = (struct ECPGtype *) mm_alloc(sizeof(struct ECPGtype));

	ne->typ = typ;
	ne->size = siz;
	ne->u.element = 0;

	return ne;
}

struct ECPGtype *
ECPGmake_array_type(struct ECPGtype * typ, long siz)
{
	struct ECPGtype *ne = ECPGmake_simple_type(ECPGt_array, siz);

	ne->u.element = typ;

	return ne;
}

struct ECPGtype *
ECPGmake_struct_type(struct ECPGstruct_member * rm, enum ECPGttype type)
{
	struct ECPGtype *ne = ECPGmake_simple_type(type, 1);

	ne->u.members = ECPGstruct_member_dup(rm);

	return ne;
}

static const char *
get_type(enum ECPGttype typ)
{
	switch (typ)
	{
		case ECPGt_char:
			return ("ECPGt_char");
			break;
		case ECPGt_unsigned_char:
			return ("ECPGt_unsigned_char");
			break;
		case ECPGt_short:
			return ("ECPGt_short");
			break;
		case ECPGt_unsigned_short:
			return ("ECPGt_unsigned_short");
			break;
		case ECPGt_int:
			return ("ECPGt_int");
			break;
		case ECPGt_unsigned_int:
			return ("ECPGt_unsigned_int");
			break;
		case ECPGt_long:
			return ("ECPGt_long");
			break;
		case ECPGt_unsigned_long:
			return ("ECPGt_unsigned_int");
			break;
		case ECPGt_float:
			return ("ECPGt_float");
			break;
		case ECPGt_double:
			return ("ECPGt_double");
			break;
		case ECPGt_bool:
			return ("ECPGt_bool");
			break;
		case ECPGt_varchar:
			return ("ECPGt_varchar");
		case ECPGt_NO_INDICATOR:		/* no indicator */
			return ("ECPGt_NO_INDICATOR");
			break;
		case ECPGt_char_variable:		/* string that should not be
										 * quoted */
			return ("ECPGt_char_variable");
			break;
		default:
			sprintf(errortext, "illegal variable type %d\n", typ);
			yyerror(errortext);
	}

	return NULL;
}

/* Dump a type.
   The type is dumped as:
   type-tag <comma>				   - enum ECPGttype
   reference-to-variable <comma>   - void *
   size <comma>					   - long size of this field (if varchar)
   arrsize <comma>				   - long number of elements in the arr
   offset <comma>				   - offset to the next element
   Where:
   type-tag is one of the simple types or varchar.
   reference-to-variable can be a reference to a struct element.
   arrsize is the size of the array in case of array fetches. Otherwise 0.
   size is the maxsize in case it is a varchar. Otherwise it is the size of
   the variable (required to do array fetches of structs).
 */
static void ECPGdump_a_simple(FILE *o, const char *name, enum ECPGttype typ,
				  long varcharsize,
				  long arrsiz, const char *siz, const char *prefix);
static void ECPGdump_a_struct(FILE *o, const char *name, const char *ind_name, long arrsiz,
				  struct ECPGtype * typ, struct ECPGtype * ind_typ, const char *offset, const char *prefix, const char *ind_prefix);


void
ECPGdump_a_type(FILE *o, const char *name, struct ECPGtype * typ, const char *ind_name, struct ECPGtype * ind_typ, const char *prefix, const char *ind_prefix)
{
	if (ind_typ == NULL)
	{
		ind_typ = &ecpg_no_indicator;
		ind_name = "no_indicator";
	}

	switch (typ->typ)
	{
		case ECPGt_array:
			switch (typ->u.element->typ)
			{
				case ECPGt_array:
					yyerror("No nested arrays allowed (except strings)");		/* array of array */
					break;
				case ECPGt_struct:
				case ECPGt_union:
					ECPGdump_a_struct(o, name, ind_name, typ->size, typ->u.element, ind_typ->u.element, NULL, prefix, ind_prefix);
					break;
				default:
					if (!IS_SIMPLE_TYPE(typ->u.element->typ))
						yyerror("Internal error: unknown datatype, please inform pgsql-bugs@postgresql.org");

					ECPGdump_a_simple(o, name, typ->u.element->typ,
						  typ->u.element->size, typ->size, NULL, prefix);
					if (ind_typ->typ == ECPGt_NO_INDICATOR)
						ECPGdump_a_simple(o, ind_name, ind_typ->typ, ind_typ->size, -1, NULL, ind_prefix);
					else
					{
						if (ind_typ->typ != ECPGt_array)
						{
							fprintf(stderr, "Indicator for an array has to be array too.\n");
							exit(INDICATOR_NOT_ARRAY);
						}
						ECPGdump_a_simple(o, ind_name, ind_typ->u.element->typ,
										  ind_typ->u.element->size, ind_typ->size, NULL, prefix);
					}
			}
			break;
		case ECPGt_struct:
			ECPGdump_a_struct(o, name, ind_name, 1, typ, ind_typ, NULL, prefix, ind_prefix);
			break;
		case ECPGt_union:		/* cannot dump a complete union */
			yyerror("Type of union has to be specified");
			break;
		case ECPGt_char_variable:
			ECPGdump_a_simple(o, name, typ->typ, 1, 1, NULL, prefix);
			ECPGdump_a_simple(o, ind_name, ind_typ->typ, ind_typ->size, -1, NULL, ind_prefix);
			break;
		default:
			ECPGdump_a_simple(o, name, typ->typ, typ->size, -1, NULL, prefix);
			ECPGdump_a_simple(o, ind_name, ind_typ->typ, ind_typ->size, -1, NULL, ind_prefix);
			break;
	}
}


/* If siz is NULL, then the offset is 0, if not use siz as a
   string, it represents the offset needed if we are in an array of structs. */
static void
ECPGdump_a_simple(FILE *o, const char *name, enum ECPGttype typ,
				  long varcharsize,
				  long arrsize,
				  const char *siz,
				  const char *prefix
)
{
	if (typ == ECPGt_NO_INDICATOR)
		fprintf(o, "\n\tECPGt_NO_INDICATOR, NULL , 0L, 0L, 0L, ");
	else
	{
		char	   *variable = (char *) mm_alloc(strlen(name) + ((prefix == NULL) ? 0 : strlen(prefix)) + 4);
		char	   *offset = (char *) mm_alloc(strlen(name) + strlen("sizeof(struct varchar_)") + 1);

		/* we have to use the pointer except for arrays with given bounds */
		if (arrsize > 0)
			sprintf(variable, "(%s%s)", prefix ? prefix : "", name);
		else
			sprintf(variable, "&(%s%s)", prefix ? prefix : "", name);

		switch (typ)
		{
			case ECPGt_varchar:
				sprintf(offset, "sizeof(struct varchar_%s)", name);
				break;
			case ECPGt_char:
			case ECPGt_unsigned_char:
			case ECPGt_char_variable:
				sprintf(offset, "%ld*sizeof(char)", varcharsize == 0 ? 1 : varcharsize);
				break;
			default:
				sprintf(offset, "sizeof(%s)", ECPGtype_name(typ));
				break;
		}

		if (arrsize < 0)
			arrsize = 1;

		if (siz == NULL)
			fprintf(o, "\n\t%s,%s,%ldL,%ldL,%s, ", get_type(typ), variable, varcharsize, arrsize, offset);
		else
			fprintf(o, "\n\t%s,%s,%ldL,%ldL,%s, ", get_type(typ), variable, varcharsize, arrsize, siz);

		free(variable);
		free(offset);
	}
}


/* Penetrate a struct and dump the contents. */
static void
ECPGdump_a_struct(FILE *o, const char *name, const char *ind_name, long arrsiz, struct ECPGtype * typ, struct ECPGtype * ind_typ, const char *offsetarg, const char *prefix, const char *ind_prefix)
{

	/*
	 * If offset is NULL, then this is the first recursive level. If not
	 * then we are in a struct in a struct and the offset is used as
	 * offset.
	 */
	struct ECPGstruct_member *p,
			   *ind_p = NULL;
	char		obuf[BUFSIZ];
	char		pbuf[BUFSIZ],
				ind_pbuf[BUFSIZ];
	const char *offset;

	if (offsetarg == NULL)
	{
		sprintf(obuf, "sizeof(%s)", name);
		offset = obuf;
	}
	else
		offset = offsetarg;

	sprintf(pbuf, "%s%s.", prefix ? prefix : "", name);
	prefix = pbuf;

	sprintf(ind_pbuf, "%s%s.", ind_prefix ? ind_prefix : "", ind_name);
	ind_prefix = ind_pbuf;

	if (ind_typ != NULL)
		ind_p = ind_typ->u.members;
	for (p = typ->u.members; p; p = p->next)
	{
		ECPGdump_a_type(o, p->name, p->typ, (ind_p != NULL) ? ind_p->name : NULL, (ind_p != NULL) ? ind_p->typ : NULL, prefix, ind_prefix);
		if (ind_p != NULL)
			ind_p = ind_p->next;
	}
}

void
ECPGfree_struct_member(struct ECPGstruct_member * rm)
{
	while (rm)
	{
		struct ECPGstruct_member *p = rm;

		rm = rm->next;
		free(p->name);
		free(p->typ);
		free(p);
	}
}

void
ECPGfree_type(struct ECPGtype * typ)
{
	if (!IS_SIMPLE_TYPE(typ->typ))
	{
		switch (typ->typ)
		{
			case ECPGt_array:
				switch (typ->u.element->typ)
				{
					case ECPGt_array:
						yyerror("internal error, found multi-dimensional array\n");
						break;
					case ECPGt_struct:
					case ECPGt_union:
						/* Array of structs. */
						ECPGfree_struct_member(typ->u.element->u.members);
						free(typ->u.element);
						break;
					default:
						if (!IS_SIMPLE_TYPE(typ->u.element->typ))
							yyerror("Internal error: unknown datatype, please inform pgsql-bugs@postgresql.org");

						free(typ->u.element);
				}
				break;
			case ECPGt_struct:
			case ECPGt_union:
				ECPGfree_struct_member(typ->u.members);
				break;
			default:
				sprintf(errortext, "illegal variable type %d\n", typ->typ);
				yyerror(errortext);
				break;
		}
	}
	free(typ);
}
