#define _DEFAULT_SOURCE
#define _BSD_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include <unistd.h>
#include <assert.h>

#include <pcilib.h>
#include <pcilib/tools.h>
#include <pcilib/error.h>
#include <pcilib/locking.h>
#include <pcilib/model.h>
#include <pcilib/datacpy.h>

#include "registers.h"
#include "private.h"



typedef struct pcidev_register_context_s pcidev_register_context_t;

struct pcidev_register_context_s {
    pcilib_register_bank_context_t bank_ctx;	/**< the bank context associated with the software registers */
    pcilib_lock_t *lock;			/**< the lock to serialize access through GPIO */
};


pcilib_register_bank_context_t* pcidev_regfile_open(pcilib_t *ctx, pcilib_register_bank_t bank, const char* model, const void *args) {
	pcidev_register_context_t *bank_ctx;

	bank_ctx = calloc(1, sizeof(pcidev_register_context_t));
	if (!bank_ctx) {
	    pcilib_error("Memory allocation for bank context has failed");
	    return NULL;
	}

	bank_ctx->lock = pcilib_get_lock(ctx, PCILIB_LOCK_FLAGS_DEFAULT, "registers");
	if (!bank_ctx->lock) {
	    pcidev_regfile_close(ctx, (pcilib_register_bank_context_t*)bank_ctx);
	    pcilib_error("Failed to initialize a lock to protect CMOSIS register bank");
	    return NULL;
	}

	srandom(1);

	return (pcilib_register_bank_context_t*)bank_ctx;
}

void pcidev_regfile_close(pcilib_t *ctx, pcilib_register_bank_context_t *reg_bank_ctx) {
	pcidev_register_context_t *bank_ctx = (pcidev_register_context_t*)reg_bank_ctx;

	if (bank_ctx->lock)
	    pcilib_return_lock(ctx, PCILIB_LOCK_FLAGS_DEFAULT, bank_ctx->lock);
	free(bank_ctx);
}


int pcidev_register_read(pcilib_t *ctx, pcilib_register_bank_context_t *reg_bank_ctx, pcilib_register_addr_t addr, pcilib_register_value_t *value) {
    int err;
    uint32_t val;

    pcidev_register_context_t *bank_ctx = (pcidev_register_context_t*)reg_bank_ctx;
    const pcilib_register_bank_description_t *bank = reg_bank_ctx->bank;
    

retry:
    err = pcilib_lock(bank_ctx->lock);
    if (err) {
	pcilib_error("Error (%i) obtaining a lock to serialize access to registers ", err);
	return err;
    }

    val = random();

    pcilib_unlock(bank_ctx->lock);

    *value = val;

    return 0;
}

int pcidev_register_write(pcilib_t *ctx, pcilib_register_bank_context_t *reg_bank_ctx, pcilib_register_addr_t addr, pcilib_register_value_t value) {
    int err;

    pcidev_register_context_t *bank_ctx = (pcidev_register_context_t*)reg_bank_ctx;
    const pcilib_register_bank_description_t *bank = reg_bank_ctx->bank;
    
retry:
    err = pcilib_lock(bank_ctx->lock);
    if (err) {
	pcilib_error("Error (%i) obtaining a lock to serialize access to CMOSIS registers ", err);
	return err;
    }

    pcilib_unlock(bank_ctx->lock);

    return 0;
}