/*
 * Parses RPM spec file into Makefile fragment. See
 *
 * http://fedora.redhat.com/docs/drafts/rpm-guide-en/ch-programming-c.html
 *
 * Mark Huang <mlhuang@cs.princeton.edu>
 * Copyright (C) 2006 The Trustees of Princeton University
 *
 * $Id: parseSpec.c,v 1.7 2007/07/23 15:12:44 mef Exp $
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <libgen.h>
#include <errno.h>
#include <rpm/rpmlib.h>
#include <rpm/rpmts.h>
#include <rpm/rpmcli.h>
#include <rpm/rpmbuild.h>
#include <rpm/rpmspec.h>

/* the structure describing the options we take and the defaults */
static struct poptOption optionsTable[] = {
	{ NULL, '\0', POPT_ARG_INCLUDE_TABLE, rpmcliAllPoptTable, 0,
	  "Common options for all rpm modes and executables:",
	  NULL },

	POPT_AUTOALIAS
	POPT_AUTOHELP
	POPT_TABLEEND
};

/* Stolen from rpm/build/spec.c:rpmspecQuery() */
Spec
rpmspecGet(rpmts ts, const char * arg)
{
	char * buildRoot = NULL;
	int recursing = 0;
	char * passPhrase = "";
	char *cookie = NULL;
	int anyarch = 1;
	int force = 1;

	if (parseSpec(ts, arg, "/", buildRoot, recursing, passPhrase,
		      cookie, anyarch, force)) {
		fprintf(stderr, "query of specfile %s failed, can't parse\n", arg);
		return NULL;
	}

	return rpmtsSpec(ts);
}

int
main(int argc, char *argv[])
{
	poptContext context;
	rpmts ts = NULL;
	int ec = 0;
	Spec spec;
	struct Source *source;
	Package pkg;
	const char *name, *version, *release, *arch, *unused;

	/* BEGIN: support to pull out --target from the args list */
	int  alen, i;
	char *target = NULL;
	int args = 1;
	int tlen = strlen("--target");

	/* walk argv list looking for --target */
	while ((args+1)<argc) {
	  if(strncmp(argv[args],"--target",tlen)==0){
	    char **dash;

	    /* get arch component of the --target option */
	    dash = (char**)strchr(argv[args+1],'-');
	    if (dash != NULL) *dash=NULL;

	    /* copy arch component of --target option to target */
	    alen = strnlen(argv[args+1],32);
	    target = (char*)malloc(alen+1);
	    if (target == NULL) return errno;
	    strncpy(target,argv[args+1],alen);
	    target[alen]='\0';

	    /* change argc, argv to take out the "--target xxx" */
	    for (i=args;i<argc;i++) argv[i]=argv[i+2];
	    argc-=2;

	    break;
	  }
	  args++;
	}
	argv[1]=argv[argc-1];
	argv[2]=0;
	argc=2;
	/* END: support to pull out --target from the args list */

	/* Parse common options for all rpm modes and executables */
	context = rpmcliInit(argc, argv, optionsTable);

	/* Create transaction state */
	ts = rpmtsCreate();

	/* Parse spec file. The rpmcli functions don't allow you to
	 * access the Spec structure directly, so we call our own
	 * version of rpmSpecQuery() directly. */
	spec = rpmspecGet(ts, argv[1]);
	if (!spec)
		goto done;

	/* Print sources */
	for (source = spec->sources; source; source = source->next) {
		char fullSource[PATH_MAX];

		strncpy(fullSource, source->fullSource, sizeof(fullSource));
		printf("SOURCES += SOURCES/%s\n", basename(fullSource));
	}

	/* Get SRPM name from name of first package */ 
	pkg = spec->packages;
	name = version = release = NULL;
	(void) headerNVR(pkg->header, &name, &version, &release);
	if (name && version && release)
		printf("SRPM := SRPMS/%s-%s-%s.src.rpm\n",
		       name, version, release);

	/* Print non-empty packages */
	for (pkg = spec->packages; pkg != NULL; pkg = pkg->next) {
		name = version = release = arch = NULL;
		(void) headerNEVRA(pkg->header, &name, &unused, &version, &release, &arch);
		if (name && version && release && arch) {
			if (!pkg->fileList)
				printf("# Empty\n# ");

			if (target != NULL) {
			  if (strcmp(arch,target)!=0) {
			    arch=target;
			  }
			}
			printf("RPMS += RPMS/%s/%s-%s-%s.%s.rpm\n",
			       arch, name, version, release, arch);
		}
	}

	spec = freeSpec(spec);

 done:
	ts = rpmtsFree(ts);
	context = rpmcliFini(context);
	return ec;
}