// Copyright 2023 alexevier <alexevier@proton.me>
// licensed under the zlib license <https://www.zlib.net/zlib_license.html>

#ifndef lexlib_vec_h
#define lexlib_vec_h

#include<stddef.h>
#include"common.h"

/* Structure of Vector
	|head       |access pointer|
	|size_t     |any type      |
	|len|cap|tze|data..........|

	this makes it posible to use as a normal array without
	going through struct.data[777]; just vec[777].

	it just should not be freed/reallocated direcly;
	use lexlibVecNew(), lexlibVecDelete(), lexlibVecResize().

	a example can be found at the end of this header.
*/

// just a way of declaring a lexlib vec to make it easier to spot
// and avoid confusion with a normal array/ptr.
#define LexlibVec(T) T*

// create a new initialized vector, all elements are zero'ed.
// len can be 0.
// its undefined behavior to use the vector for a different type.
// returns NULL on error (can't allocate memory).
#define lexlibVecNew(len, T) lexlibVecNew_(len, sizeof(T))
LEXLIB_EXTERN void *lexlibVecNew_(size_t len, size_t typeSize);

// delete a vector and its data.
// does nothing if NULL.
LEXLIB_EXTERN void lexlibVecDelete(void *vec);

// get element from vector.
// returns NULL if out of bounds (index >= vec.len).
LEXLIB_EXTERN void *lexlibVecGet(const void *vec, size_t index);

// push a element onto the vector; copies the object.
// WARNING other pointers of the vector itself may be dangling afterwards.
// returns 0 on success, nonzero otherwise (couldn't reallocate vector).
#define lexlibVecPush(V, O) lexlibVecPush_((void**)&(V), O)
LEXLIB_EXTERN int lexlibVecPush_(void **vec, const void *obj);

// pops the last element off the vector.
LEXLIB_EXTERN void lexlibVecPop(void *vec);

// insert a element in the vector; copies the object.
// shifts all the elements after to the right.
// if index is out of bounds (index > vec.len) it will fail.
// WARNING other pointers of the vector itself may be dangling afterwards.
// returns 0 on success, nonzero otherwise (couldn't reallocate or invalid index).
#define lexlibVecInsert(V, I, O) lexlibVecInsert_((void**)&(V), I, O)
LEXLIB_EXTERN int lexlibVecInsert_(void **vec, size_t index, const void *obj);

// remove a element in the vector.
// shifts all the elements after to the left.
// if index is out of bounds (index >= vec.len) it will fail.
// returns 0 on success, nonzero otherwise (invalid index).
LEXLIB_EXTERN int lexlibVecRemove(void *vec, size_t index);

// resize a vector; will truncate.
// WARNING other pointers of the vector itself may be dangling afterwards.
// returns 0 on success, nonzero otherwise (couldn't reallocate).
LEXLIB_EXTERN int lexlibVecResize(void **vec, size_t newcap);

// find the first ocurrence of obj.
// performs memcmp for each element; O(n)
// returns NULL if the element can't be found.
LEXLIB_EXTERN void *lexlibVecFind(const void *vec, const void *obj);

// swap 2 elements.
// returns 0 on success, nonzero otherwise (invalid index/failed to allocate tmp buffer).
LEXLIB_EXTERN int lexlibVecSwap(void *vec, size_t a, size_t b);

// clear the data contained by the vector.
// doesn't deallocate.
LEXLIB_EXTERN void lexlibVecClear(void *vec);

// get the count of elements.
LEXLIB_EXTERN size_t lexlibVecLen(const void *vec);

// get the current capacity of the vector.
LEXLIB_EXTERN size_t lexlibVecCap(const void *vec);

#endif

/*
void lexlibVecExample(void){
	// create a new vector for floats.
	// can aslo be declared as "float *vec = ...;"
	LexlibVec(float) vec = lexlibVecNew(0, *vec);
	float value = 777.0f;
	float pi = 3.14f;

	// push new values to the vector
	lexlibVecPush(vec, &value);
	lexlibVecPush(vec, &(float){1.234f});

	// insert value
	lexlibVecInsert(vec, 0, &pi);

	// remove
	lexlibVecRemove(vec, 1);

	// access
	if(vec[0] != 3.14f){
		printf("vec[0] is not 3.14\n");
		abort();
	}
	if(vec[1] != 1.234f){
		printf("vec[1] is not 1.234\n");
		abort();
	}

	// delete/free the vector
	lexlibVecDelete(vec);
}
*/