#include "cms_err.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>

#ifdef DEBUG
	#include <error.h>
#endif

static char* get_error_message(cms_err* err)
{
	switch (err->code)
	{
		case CMS_ERR_NONE:
			return "";
		case CMS_ERR_UNKNOWN:
			return "Unknown error.";
		case CMS_ERR_ALLOC:
			return "Memory allocation failed.";
		case CMS_ERR_PARSE:
			return "Parse error.";
		case CMS_ERR_NOENT:
			return "No such file or directory.";
		case CMS_ERR_NOTFILE:
			return "Not a file.";
		case CMS_ERR_NOTDIR:
			return "Not a directory.";
		case CMS_ERR_FILEEXISTS:
			return "File exists.";
		case CMS_ERR_FILEREAD:
			return "Failed to read file.";
		case CMS_ERR_DIREXISTS:
			return "Directory exists.";
		case CMS_ERR_PERM:
			return "Permission denied.";
		case CMS_ERR_INITED:
			return "Already initiated.";
		case CMS_ERR_NOTINITED:
			return "Not initiated.";
	}
}

cms_err* _cms_err_create(cms_err_code code, char* msg, const char* file, int line)
{
	//We want to just return NULL if there is no error
	if (code == CMS_ERR_NONE)
		return NULL;

	cms_err* err = malloc(sizeof(cms_err));
	if (err == NULL)
	{
		fprintf(stderr, "Failed to allocate memory.\n");
		exit(1);
	}

	err->code = code;

	if (msg == NULL)
	{
		err->msg = NULL;
	}
	else
	{
		size_t msglen = strlen(msg) + 1;
		err->msg = malloc(msglen * sizeof(char));
		if (err->msg == NULL)
		{
			fprintf(stderr, "Failed to allocate memory.\n");
			exit(1);
		}

		memcpy(err->msg, msg, msglen * sizeof(char));
	}

	err->file = file;
	err->line = line;

	return err;
}

void cms_err_free(cms_err* err)
{
	//The error can be null, in which case, we don't want to do anything
	if (err == NULL)
		return;

	free(err->msg);
	free(err);
}

void cms_err_panic(cms_err* err)
{
	if (!err)
		return;

#ifdef DEBUG
	fprintf(stderr, "File %s, line %i:\n\t", err->file, err->line);
#endif

	if (err->msg == NULL)
		fprintf(stderr, "Error: %s\n", get_error_message(err));
	else
		fprintf(stderr, "Error: %s: %s\n", err->msg, get_error_message(err));

	exit(1);
}

cms_err* _cms_err_from_std_err(int err, const char* file, int line)
{
	switch (err)
	{
	case EACCES:
		return _cms_err_create(CMS_ERR_PERM, NULL, file, line);
	case EEXIST:
		return _cms_err_create(CMS_ERR_FILEEXISTS, NULL, file, line);
	case EFAULT:
		return _cms_err_create(CMS_ERR_PERM, NULL, file, line);
	case EISDIR:
		return _cms_err_create(CMS_ERR_NOTFILE, NULL, file, line);
	case ENOENT:
		return _cms_err_create(CMS_ERR_NOENT, NULL, file, line);
	case ENOMEM:
		return _cms_err_create(CMS_ERR_ALLOC, NULL, file, line);
	case ENOTDIR:
		return _cms_err_create(CMS_ERR_NOTDIR, NULL, file, line);
	case EROFS:
		return _cms_err_create(CMS_ERR_PERM, NULL, file, line);
	default:
		return _cms_err_create(CMS_ERR_UNKNOWN, NULL, file, line);
	}
}