/**
 * cf_debug.c
 */
#include "cf_debug.h"
#include "cf_local.h"

#include <stdlib.h>
#include <ctype.h>
#include <stdarg.h>
#include <string.h>

#ifdef _WIN32
# include <io.h>
#else
# include <unistd.h>
#endif

#define IS_READABLE_CHAR(__c)		(' ' <= __c && __c <= '~')

#define CHECK_INVALID_CTX(__ctx)			\
	if (__ctx == NULL)						\
		return CF_ERROR_DEBUG_INVALID_CTX

#define GET_CTX_OSTREAM(__ctx)				\
	((((CF_DEBUG_CTX *)__ctx)->fp == NULL)	\
	 ? stderr								\
	 : ((CF_DEBUG_CTX *)__ctx)->fp)

typedef struct __cf_debug_callstack__
{
	char	file[NAME_LENGTH + 1];
	char	func[NAME_LENGTH + 1];
	int		line;

	struct __cf_debug_callstack__	* caller;
} S_CF_DEBUG_CALLSTACK, CF_DEBUG_CALLSTACK;

typedef struct __cf_debug_ctx__
{
	char	file[NAME_LENGTH + 1];
	char	func[NAME_LENGTH + 1];
	int		line;

	FILE	* fp;

	CF_DEBUG_CALLSTACK	callstack;
} S_CF_DEBUG_CTX, CF_DEBUG_CTX;

static int
CF_Debug_Local_Print (FILE			* fp,
					  const char	* file,
					  const char	* func,
					  const int		line,
					  const char	* fmt,
					  va_list		valist)
{
	fprintf (fp, "[DEBUG][%s:%d][%s] ", file, line, func);
	vfprintf (fp, fmt, valist);

	return CF_OK;
}

static int
CF_Debug_Local_PrintBin (FILE					* fp,
						 const char				* file,
						 const char				* func,
						 const int				line,
						 const unsigned char	* bin,
						 const int				len)
{
	int i, j;

	for (i = 0 ; i < len ; i += 16)
	{
		fprintf (fp, "[DEBUG][%s:%d][%s] ", file, line, func);
		fprintf (fp, "%06x : ", i);

		for (j = 0 ; j < 16 ; j++)
		{
			if (i+j < len)
				fprintf (fp, "%02x ", bin[i+j]);
			else
				fprintf (fp, "   ");
		}
		fprintf (fp, " ");

		for (j = 0 ; j < 16 ; j++)
		{
			if (i+j < len)
				fprintf (fp, "%c", IS_READABLE_CHAR(bin[i+j]) ? bin[i+j] : '.');
		}
		fprintf (fp, "\n");
	}

	return CF_OK;
}

CF_Debug_Ctx
CF_Debug_CreateCtx (void)
{
	CF_DEBUG_CTX * ctx = NULL;

	ctx = (CF_DEBUG_CTX *) calloc (sizeof (CF_DEBUG_CTX), 1);

	return (CF_Debug_Ctx) ctx;
}

int
CF_Debug_DestroyCtx (CF_Debug_Ctx ctx)
{
	CF_DEBUG_CTX		* context = (CF_DEBUG_CTX *) ctx;
	CF_DEBUG_CALLSTACK	* pop = NULL;
	CF_DEBUG_CALLSTACK	* next = NULL;

	CHECK_INVALID_CTX (ctx);

	if (context->fp != NULL)
		fclose (context->fp);

	for (pop = next = context->callstack.caller ; pop ; pop = next)
	{
		next = next->caller;
		free (pop);
	}

	free (context);

	return CF_OK;
}

int
CF_Debug_SetOutputFD (CF_Debug_Ctx	ctx,
					  int			fd)
{
	int result = 0;
	int dupfd = 0;

	CF_DEBUG_CTX	* context = (CF_DEBUG_CTX *) ctx;
	FILE			* fp = NULL;

	CHECK_INVALID_CTX (ctx);

	TRY
	{
		dupfd = dup (fd);
		if (dupfd < 0)
		{
			result = -1;
			TRY_BREAK;
		}

		fp = fdopen (dupfd, "a+");
		if (fp == NULL)
		{
			close (dupfd);
			result = -2;
			TRY_BREAK;
		}

		context->fp = fp;
	}
	CATCH_IF (result < 0)
	{
		return CF_ERROR_DEBUG_SET_OUTPUT_FD;
	}

	return CF_OK;
}

int
CF_Debug_Print (FILE		* fp,
				const char	* file,
				const char	* func,
				const int	line,
				const char	* fmt, ...)
{
	va_list valist;

	va_start (valist, fmt);
	CF_Debug_Local_Print (fp, file, func, line, fmt, valist);
	va_end (valist);

	return CF_OK;
}

int
CF_Debug_PrintBin (FILE					* fp,
				   const char			* file,
				   const char			* func,
				   const int			line,
				   const unsigned char	* bin,
				   const int			len,
				   const char			* fmt, ...)
{
	va_list valist;

	va_start (valist, fmt);
	CF_Debug_Local_Print (fp, file, func, line, fmt, valist);
	va_end (valist);

	CF_Debug_Local_PrintBin (fp, file, func, line, bin, len);

	return CF_OK;
}

int
CF_Debug_UpdateCtx (CF_Debug_Ctx	ctx,
					const char		* file,
					const char		* func,
					const int		line)
{
	CF_DEBUG_CTX * context = (CF_DEBUG_CTX *) ctx;

	CHECK_INVALID_CTX (ctx);

	strncpy (context->file, file, strlen (file));
	strncpy (context->func, func, strlen (func));
	context->line = line;

	return CF_OK;
}

int
CF_Debug_Trace (CF_Debug_Ctx	ctx,
				const char		* fmt, ...)
{
	va_list			valist;
	CF_DEBUG_CTX	* context = (CF_DEBUG_CTX *) ctx;

	CHECK_INVALID_CTX (ctx);

	va_start (valist, fmt);
	CF_Debug_Local_Print (GET_CTX_OSTREAM (context),
						  context->file,
						  context->func,
						  context->line,
						  fmt, valist);
	va_end (valist);

	return CF_OK;
}

int
CF_Debug_TraceBin (CF_Debug_Ctx			ctx,
				   const unsigned char	* bin,
				   const int			len,
				   const char			* fmt, ...)
{
	va_list			valist;
	CF_DEBUG_CTX	* context = (CF_DEBUG_CTX *) ctx;
 
	CHECK_INVALID_CTX (ctx);

	va_start (valist, fmt);
	CF_Debug_Local_Print (GET_CTX_OSTREAM (context),
						  context->file,
						  context->func,
						  context->line,
						  fmt, valist);
	va_end (valist);

	CF_Debug_Local_PrintBin (GET_CTX_OSTREAM (context),
							 context->file,
							 context->func,
							 context->line,
							 bin, len);

	return CF_OK;
}

int
CF_Debug_CallStackPush (CF_Debug_Ctx	ctx,
						const char		* file,
						const char		* func,
						const int		line)
{
	CF_DEBUG_CTX		* context = (CF_DEBUG_CTX *) ctx;
	CF_DEBUG_CALLSTACK	* push = NULL;

	CHECK_INVALID_CTX (ctx);

	push = (CF_DEBUG_CALLSTACK *) calloc (sizeof (CF_DEBUG_CALLSTACK), 1);
	if (push == NULL)
		return CF_ERROR_DEBUG_PUSH_CALLSTACK;

	/* push to callstack */
	sprintf (push->file, "%s", file);
	sprintf (push->func, "%s", func);
	push->line = line;
	push->caller = context->callstack.caller;
	context->callstack.caller = push;

	CF_Debug_UpdateCtx (ctx, file, func, line);

	return CF_OK;
}

int
CF_Debug_CallStackPop (CF_Debug_Ctx			ctx,
					   CF_Debug_CallStack	* callstack)
{
	CF_DEBUG_CTX		* context = (CF_DEBUG_CTX *) ctx;
	CF_DEBUG_CALLSTACK	* pop = NULL;

	CHECK_INVALID_CTX (ctx);

	pop = context->callstack.caller;
	if (pop == NULL)
		return CF_ERROR_DEBUG_POP_CALLSTACK;

	if (callstack != NULL)
	{
		sprintf (callstack->file    , "%s", pop->file);
		sprintf (callstack->function, "%s", pop->func);
		callstack->line = pop->line;
	}

	memset (context->file, 0x00, sizeof (context->file));
	memset (context->func, 0x00, sizeof (context->func));
	context->line = 0;

	/* restore current context */
	if (pop->caller != NULL)
	{
		CF_Debug_UpdateCtx (ctx,
							pop->caller->file,
							pop->caller->func, 
							pop->caller->line);
	}

	context->callstack.caller = pop->caller;
	free (pop);

	return CF_OK;
}