/*-
 * Copyright (c) 2010-2014 Juan Romero Pardines.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <stdarg.h>
#include <unistd.h>
#include <inttypes.h>

#include <xbps.h>

#ifdef __clang__
#pragma clang diagnostic ignored "-Wformat-nonliteral"
#endif

#ifndef __arraycount
# define __arraycount(a) (sizeof(a) / sizeof(*(a)))
#endif

#define _DGRAPH_CFFILE	"xbps-dgraph.conf"

/*
 * Properties written to default configuration file.
 */
struct defprops {
	const char *sect;
	const char *prop;
	const char *val;
} dfprops[] = {
	{ .sect = "graph", .prop = "rankdir", .val = "LR" },
	{ .sect = "graph", .prop = "ranksep", .val = ".1" },
	{ .sect = "graph", .prop = "nodesep", .val = ".1" },
	{ .sect = "graph", .prop = "pack", .val = "true" },
	{ .sect = "graph", .prop = "splines", .val = "polyline" },
	{ .sect = "graph", .prop = "ratio", .val = "compress" },

	{ .sect = "edge", .prop = "constraint", .val = "true" },
	{ .sect = "edge", .prop = "arrowhead", .val = "vee" },
	{ .sect = "edge", .prop = "arrowsize", .val = ".4" },
	{ .sect = "edge", .prop = "fontname", .val = "Sans" },
	{ .sect = "edge", .prop = "fontsize", .val = "8" },

	{ .sect = "node", .prop = "height", .val = ".1" },
	{ .sect = "node", .prop = "width", .val = ".1" },
	{ .sect = "node", .prop = "shape", .val = "box" },
	{ .sect = "node", .prop = "fontname", .val = "Sans" },
	{ .sect = "node", .prop = "fontsize", .val = "8" },

	{ .sect = "node-sub", .prop = "main-style", .val = "filled" },
	{ .sect = "node-sub", .prop = "main-fillcolor", .val = "darksalmon" },
	{ .sect = "node-sub", .prop = "style", .val = "filled" },
	{ .sect = "node-sub", .prop = "fillcolor", .val = "yellowgreen" },
	{ .sect = "node-sub", .prop = "opt-style", .val = "filled" },
	{ .sect = "node-sub", .prop = "opt-fillcolor", .val = "grey" }
};

static void __attribute__((noreturn))
die(const char *fmt, ...)
{
	va_list ap;
	int save_errno = errno;

	va_start(ap, fmt);
	fprintf(stderr, "xbps-dgraph: ERROR ");
	vfprintf(stderr, fmt, ap);
	if (save_errno)
		fprintf(stderr, " (%s)\n", strerror(save_errno));
	else
		fprintf(stderr, "\n");
	va_end(ap);
	exit(EXIT_FAILURE);
}

static void __attribute__((noreturn))
usage(void)
{
	fprintf(stdout,
	"Usage: xbps-dgraph [options] <pkgname>\n\n"
	" Options\n"
	"    -c\t\tPath to configuration file\n"
	"    -g\t\tGenerate a default config file\n"
	"    -R\t\tEnable repository mode\n"
	"    -r\t\t<rootdir>\n\n");
	exit(EXIT_FAILURE);
}

static const char *
convert_proptype_to_string(xbps_object_t obj)
{
	switch (xbps_object_type(obj)) {
	case XBPS_TYPE_ARRAY:
		return "array";
	case XBPS_TYPE_BOOL:
		return "bool";
	case XBPS_TYPE_DICTIONARY:
		return "dictionary";
	case XBPS_TYPE_DICT_KEYSYM:
		return "dictionary key";
	case XBPS_TYPE_NUMBER:
		return "integer";
	case XBPS_TYPE_STRING:
		return "string";
	case XBPS_TYPE_DATA:
		return "data";
	default:
		return NULL;
	}
}

static xbps_dictionary_t
create_defconf(void)
{
	xbps_dictionary_t d, d2;
	struct defprops *dfp;

	d = xbps_dictionary_create();

	d2 = xbps_dictionary_create();
	xbps_dictionary_set(d, "graph", d2);
	xbps_object_release(d2);

	d2 = xbps_dictionary_create();
	xbps_dictionary_set(d, "edge", d2);
	xbps_object_release(d2);

	d2 = xbps_dictionary_create();
	xbps_dictionary_set(d, "node", d2);
	xbps_object_release(d2);

	d2 = xbps_dictionary_create();
	xbps_dictionary_set(d, "node-sub", d2);
	xbps_object_release(d2);

	for (unsigned int i = 0; i < __arraycount(dfprops); i++) {
		dfp = &dfprops[i];
		d2 = xbps_dictionary_get(d, dfp->sect);
		xbps_dictionary_set_cstring_nocopy(d2, dfp->prop, dfp->val);
	}

	return d;
}

static void
generate_conf_file(void)
{
	xbps_dictionary_t d;

	d = create_defconf();
	if (xbps_dictionary_externalize_to_file(d, _DGRAPH_CFFILE) == false) {
		xbps_object_release(d);
		die("couldn't write conf_file to %s", _DGRAPH_CFFILE);
	}
	xbps_object_release(d);
	printf("Wrote configuration file: %s\n", _DGRAPH_CFFILE);
}

static void
write_conf_property_on_stream(FILE *f,
			      const char *section,
			      xbps_dictionary_t confd)
{
	xbps_array_t allkeys, allkeys2;
	xbps_dictionary_keysym_t dksym, dksym2;
	xbps_object_t keyobj, keyobj2;
	const char *cf_val, *keyname, *keyname2;

	/*
	 * Iterate over the main dictionary.
	 */
	allkeys = xbps_dictionary_all_keys(confd);
	for (unsigned int i = 0; i < xbps_array_count(allkeys); i++) {
		dksym = xbps_array_get(allkeys, i);
		keyname = xbps_dictionary_keysym_cstring_nocopy(dksym);
		keyobj = xbps_dictionary_get_keysym(confd, dksym);
		if (strcmp(keyname, section))
			continue;

		/*
		 * Iterate over the dictionary sections [edge/graph/node].
		 */
		allkeys2 = xbps_dictionary_all_keys(keyobj);
		for (unsigned int x = 0; x < xbps_array_count(allkeys2); x++) {
			dksym2 = xbps_array_get(allkeys2, x);
			keyname2 = xbps_dictionary_keysym_cstring_nocopy(dksym2);
			keyobj2 = xbps_dictionary_get_keysym(keyobj, dksym2);

			cf_val = xbps_string_cstring_nocopy(keyobj2);
			fprintf(f, "%s=\"%s\"", keyname2, cf_val);
			if (x + 1 >= xbps_array_count(allkeys2))
				continue;

			fprintf(f, ",");
		}
	}
}

static char *
strip_dashes_from_key(const char *str)
{
	char *p;
	size_t i;

	p = strdup(str);
	if (p == NULL)
		die("%s alloc p", __func__);

	for (i = 0; i < strlen(p); i++) {
		if (p[i] == '-')
			p[i] = '_';
	}
	return p;
}

static void
parse_array_in_pkg_dictionary(FILE *f, xbps_dictionary_t plistd,
			      xbps_dictionary_t sub_confd,
			      xbps_array_t allkeys)
{
	xbps_dictionary_keysym_t dksym;
	xbps_object_t keyobj, sub_keyobj;
	const char *tmpkeyname, *cfprop;
	char *keyname;

	for (unsigned int i = 0; i < xbps_array_count(allkeys); i++) {
		dksym = xbps_array_get(allkeys, i);
		tmpkeyname = xbps_dictionary_keysym_cstring_nocopy(dksym);
		keyobj = xbps_dictionary_get_keysym(plistd, dksym);
		keyname = strip_dashes_from_key(tmpkeyname);

		fprintf(f, "	main -> %s [label=\"%s\"];\n",
		    keyname, convert_proptype_to_string(keyobj));

		xbps_dictionary_get_cstring_nocopy(sub_confd, "opt-style", &cfprop);
		/*
		 * Process array objects.
		 */
		xbps_dictionary_get_cstring_nocopy(sub_confd, "style", &cfprop);
		if (xbps_object_type(keyobj) == XBPS_TYPE_ARRAY) {
			for (unsigned int x = 0; x < xbps_array_count(keyobj); x++) {
				sub_keyobj = xbps_array_get(keyobj, x);
				if (xbps_object_type(sub_keyobj) == XBPS_TYPE_STRING) {
					/*
					 * Process arrays of strings.
					 */
					fprintf(f, "	%s -> %s_%u_string "
					    "[label=\"string\"];\n",
					    keyname, keyname, x);
					xbps_dictionary_get_cstring_nocopy(sub_confd,
					    "style", &cfprop);
					fprintf(f, "	%s_%u_string [style=\"%s\",",
					    keyname, x, cfprop);
					xbps_dictionary_get_cstring_nocopy(sub_confd,
					    "fillcolor", &cfprop);
					fprintf(f, "fillcolor=\"%s\","
					    "label=\"%s\"];\n", cfprop,
					    xbps_string_cstring_nocopy(sub_keyobj));
				}
			}
			free(keyname);
			continue;
		}
		fprintf(f, "	%s -> %s_value;\n", keyname, keyname);
		xbps_dictionary_get_cstring_nocopy(sub_confd, "style", &cfprop);
		fprintf(f, "	%s_value [style=\"%s\",", keyname, cfprop);
		xbps_dictionary_get_cstring_nocopy(sub_confd,
		    "fillcolor", &cfprop);
		fprintf(f, "fillcolor=\"%s\"", cfprop);

		/*
		 * Process all other object types...
		 */
		switch (xbps_object_type(keyobj)) {
		case XBPS_TYPE_BOOL:
			fprintf(f, ",label=\"%s\"",
			    xbps_bool_true(keyobj) ? "true" : "false");
			break;
		case XBPS_TYPE_DATA:
			fprintf(f, ",label=\"%zu bytes\"", xbps_data_size(keyobj));
			break;
		case XBPS_TYPE_NUMBER:
			fprintf(f, ",label=\"%"PRIu64" bytes\"",
			    xbps_number_unsigned_integer_value(keyobj));
			break;
		case XBPS_TYPE_STRING:
			if (strcmp(keyname, "long_desc") == 0) {
				/*
				 * Do not print this obj, too large!
				 */
				fprintf(f, ",label=\"...\"");
			} else {
				fprintf(f, ",label=\"%s\"",
			    	    xbps_string_cstring_nocopy(keyobj));
			}
			break;
		default:
			break;
		}
		fprintf(f, "];\n");
		free(keyname);
	}
}

static void
create_dot_graph(struct xbps_handle *xhp,
		 FILE *f,
		 xbps_dictionary_t plistd,
		 xbps_dictionary_t confd,
		 bool repomode)
{
	xbps_dictionary_t sub_confd;
	xbps_array_t allkeys, rdeps;
	const char *pkgver, *cfprop;

	xbps_dictionary_get_cstring_nocopy(plistd, "pkgver", &pkgver);

	/*
	 * Start filling the output file...
	 */
	fprintf(f, "/* Graph created for %s by xbps-graph %s */\n\n",
	    pkgver, XBPS_RELVER);
	fprintf(f, "digraph pkg_dictionary {\n");

	/*
	 * Process the graph section in config file.
	 */
	fprintf(f, "	graph [");
	write_conf_property_on_stream(f, "graph", confd);
	fprintf(f, ",label=\"[XBPS] %s metadata properties\"];\n", pkgver);

	/*
	 * Process the edge section in config file.
	 */
	fprintf(f, "	edge [");
	write_conf_property_on_stream(f, "edge", confd);
	fprintf(f, "];\n");

	/*
	 * Process the node section in config file.
	 */
	fprintf(f, "	node [");
	write_conf_property_on_stream(f, "node", confd);
	fprintf(f, "];\n");

	/*
	 * Process the node-sub section in config file.
	 */
	fprintf(f, "	main [");
	sub_confd = xbps_dictionary_get(confd, "node-sub");
	xbps_dictionary_get_cstring_nocopy(sub_confd, "main-style", &cfprop);
	if (cfprop)
		fprintf(f, "style=%s,", cfprop);
	xbps_dictionary_get_cstring_nocopy(sub_confd, "main-fillcolor", &cfprop);
	if (cfprop)
		fprintf(f, "fillcolor=\"%s\",", cfprop);
	fprintf(f, "label=\"Dictionary\"];\n");

	/*
	 * Process all objects in package's dictionary from its metadata
	 * property list file, aka XBPS_META_PATH/.<pkgname>.plist
	 */
	if (repomode) {
		rdeps = xbps_rpool_get_pkg_revdeps(xhp, pkgver);
	} else {
		rdeps = xbps_pkgdb_get_pkg_revdeps(xhp, pkgver);
	}
	if (xbps_array_count(rdeps))
		xbps_dictionary_set(plistd, "requiredby", rdeps);

	allkeys = xbps_dictionary_all_keys(plistd);
	parse_array_in_pkg_dictionary(f, plistd, sub_confd, allkeys);
	/*
	 * Terminate the stream...
	 */
	fprintf(f, "}\n");
	fflush(f);
	fclose(f);
}

int
main(int argc, char **argv)
{
	xbps_dictionary_t plistd, confd = NULL;
	struct xbps_handle xh;
	FILE *f = NULL;
	const char *conf_file = NULL, *rootdir = NULL;
	char *outfile;
	int c, rv;
	bool repomode = false;

	while ((c = getopt(argc, argv, "c:gRr:")) != -1) {
		switch (c) {
		case 'c':
			/* Configuration file. */
			conf_file = optarg;
			break;
		case 'g':
			/* Generate auto conf file. */
			generate_conf_file();
			exit(EXIT_SUCCESS);
		case 'R':
			/* Also create graphs for reverse deps. */
			repomode = true;
			break;
		case 'r':
			/* Set different rootdir. */
			rootdir = optarg;
			break;
		case '?':
		default:
			usage();
		}
	}

	argc -= optind;
	argv += optind;

	if (argc != 1)
		usage();

	/* Initialize libxbps */
	memset(&xh, 0, sizeof(xh));
	if (rootdir != NULL)
		xbps_strlcpy(xh.rootdir, rootdir, sizeof(xh.rootdir));

	if ((rv = xbps_init(&xh)) != 0)
		die("failed to initialize libxbps: %s", strerror(rv));

	/*
	 * Output file will be <pkgname>.dot if not specified.
	 */
	outfile = xbps_xasprintf("%s.dot", argv[0]);

	/*
	 * If -c not set and config file does not exist, use defaults.
	 */
	if (conf_file == NULL)
		conf_file = _DGRAPH_CFFILE;

	confd = xbps_dictionary_internalize_from_zfile(conf_file);
	if (confd == NULL) {
		if (errno != ENOENT)
			die("cannot read conf file `%s'", conf_file);

		confd = create_defconf();
	}
	/*
	 * Internalize the plist file of the target installed package.
	 */
	if (repomode) {
		plistd = xbps_rpool_get_pkg(&xh, argv[0]);
	} else {
		plistd = xbps_pkgdb_get_pkg(&xh, argv[0]);
	}
	if (plistd == NULL)
		die("cannot find `%s' package", argv[0]);

	/*
	 * Create the output FILE.
	 */
	if ((f = fopen(outfile, "w")) == NULL)
		die("cannot create target file '%s'", outfile);

	/*
	 * Create the dot(1) graph!
	 */
	create_dot_graph(&xh, f, plistd, confd, repomode);

	exit(EXIT_SUCCESS);
}