#include <stdio.h>

#include <string.h>

#include <errno.h>

#include <unistd.h>

#include <apimagic/apimagic.h>

static const char aclr_reset[]   = "\x1b[0m";

static const char aclr_bold[]    = "\x1b[1m";

static const char aclr_red[]     = "\x1b[31m";

static const char aclr_green[]   = "\x1b[32m";

static const char aclr_blue[]    = "\x1b[34m";

static const char aclr_magenta[] = "\x1b[35m";

static char const * const amgc_error_strings[AMGC_ERR_CAP] = {

	[AMGC_ERR_FLOW_ERROR]       = "flow error: unexpected condition or other",

	[AMGC_ERR_FLEE_ERROR]       = "flees and bugs and cats and mice",

	[AMGC_ERR_NULL_CONTEXT]     = "null driver or unit context",

	[AMGC_ERR_NULL_SOURCE]      = "source file does not define any data",

	[AMGC_ERR_INVALID_CONTEXT]  = "invalid driver or unit context",

	[AMGC_ERR_INVALID_SOURCE]   = "invalid source file",

	[AMGC_ERR_SOURCE_SIZE_ZERO] = "cannot map an empty source file",

};

static const char * amgc_output_error_header(const struct amgc_error_info * erri)

{

	if (erri->eflags & AMGC_ERROR_CHILD)

		return "exec error upon";

	else if (erri->eflags & AMGC_ERROR_TOP_LEVEL)

		return "error logged in";

	else if (erri->eflags & AMGC_ERROR_NESTED)

		return "< returned to >";

	else

		return "distorted state";

}

static const char * amgc_output_unit_header(const struct amgc_error_info * erri)

{

	if (!(erri->eflags & AMGC_ERROR_CUSTOM))

		return "while opening";

	else if (erri->elibcode == AMGC_ERR_SOURCE_SIZE_ZERO)

		return "while mapping";

	else

		return "while parsing";

}

static const char * amgc_output_strerror(const struct amgc_error_info * erri)

{

	if (erri->eflags & AMGC_ERROR_CUSTOM)

		return ((erri->elibcode < 0) || (erri->elibcode >= AMGC_ERR_CAP))

			? "internal error: please report to the maintainer"

			: amgc_error_strings[erri->elibcode];

	else if (erri->eflags & AMGC_ERROR_NESTED)

		return "";

	else if (erri->eflags & AMGC_ERROR_CHILD)

		return "(see child process error messages)";

	else if (erri->esyscode == ENOBUFS)

		return "input error: string length exceeds buffer size.";

	else

		return strerror(erri->esyscode);

}

static int amgc_output_error_record_plain(

	const struct amgc_driver_ctx *	dctx,

	const struct amgc_error_info *	erri)

{

	const char * epath;

	const char * errdesc = amgc_output_strerror(erri);

	epath = erri->euctx

		? *erri->euctx->path

		: erri->eunit;

	if (epath && !(erri->eflags & AMGC_ERROR_NESTED))

		if (fprintf(stderr,"%s: [%s] '%s':\n",

				dctx->program,

				amgc_output_unit_header(erri),

				epath) < 0)

			return -1;

	if (fprintf(stderr,"%s: %s %s(), line %d%s%s.\n",

			dctx->program,

			amgc_output_error_header(erri),

			erri->efunction,

			erri->eline,

			strlen(errdesc) ? ": " : "",

			errdesc) < 0)

		return -1;

	return fflush(stderr);

}

static int amgc_output_error_record_annotated(

	const struct amgc_driver_ctx *	dctx,

	const struct amgc_error_info *	erri)

{

	const char * epath;

	const char * errdesc = amgc_output_strerror(erri);

	epath = erri->euctx

		? *erri->euctx->path

		: erri->eunit;

	if (epath && !(erri->eflags & AMGC_ERROR_NESTED))

		if (fprintf(

				stderr,

				"%s%s%s:%s %s[%s]%s %s%s'%s'%s:\n",

				aclr_bold,aclr_magenta,

				dctx->program,

				aclr_reset,

				aclr_bold,

				amgc_output_unit_header(erri),

				aclr_reset,

				aclr_bold,aclr_red,

				epath,

				aclr_reset) < 0)

			return -1;

	if (fprintf(

			stderr,

			"%s%s%s:%s %s%s%s %s%s%s()%s, %s%sline %d%s%s%s%s%s.\n",

			aclr_bold,aclr_magenta,

			dctx->program,

			aclr_reset,

			aclr_bold,

			amgc_output_error_header(erri),

			aclr_reset,

			aclr_bold,aclr_blue,

			erri->efunction,

			aclr_reset,

			aclr_bold,aclr_green,

			erri->eline,

			aclr_reset,

			strlen(errdesc) ? ": " : "",

			aclr_bold,

			amgc_output_strerror(erri),

			aclr_reset) < 0)

		return -1;

	return fflush(stderr);

}

int amgc_output_error_record(

	const struct amgc_driver_ctx *	dctx,

	const struct amgc_error_info *	erri)

{

	if (dctx->cctx->drvflags & AMGC_DRIVER_ANNOTATE_NEVER)

		return amgc_output_error_record_plain(dctx,erri);

	else if (dctx->cctx->drvflags & AMGC_DRIVER_ANNOTATE_ALWAYS)

		return amgc_output_error_record_annotated(dctx,erri);

	else if (isatty(STDERR_FILENO))

		return amgc_output_error_record_annotated(dctx,erri);

	else

		return amgc_output_error_record_plain(dctx,erri);

}

static int amgc_output_error_vector_plain(const struct amgc_driver_ctx * dctx)

{

	struct amgc_error_info ** perr;

	for (perr=dctx->errv; *perr; perr++)

		if (amgc_output_error_record_plain(dctx,*perr))

			return -1;

	return 0;

}

static int amgc_output_error_vector_annotated(const struct amgc_driver_ctx * dctx)

{

	struct amgc_error_info ** perr;

	for (perr=dctx->errv; *perr; perr++)

		if (amgc_output_error_record_annotated(dctx,*perr))

			return -1;

	return 0;

}

int amgc_output_error_vector(const struct amgc_driver_ctx * dctx)

{

	if (dctx->cctx->drvflags & AMGC_DRIVER_ANNOTATE_NEVER)

		return amgc_output_error_vector_plain(dctx);

	else if (dctx->cctx->drvflags & AMGC_DRIVER_ANNOTATE_ALWAYS)

		return amgc_output_error_vector_annotated(dctx);

	else if (isatty(STDERR_FILENO))

		return amgc_output_error_vector_annotated(dctx);

	else

		return amgc_output_error_vector_plain(dctx);

}