/*-
 * Licensed under the SPDX BSD-2-Clause identifier.
 * Use is subject to license terms, as specified in the LICENSE file.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <errno.h>

#include "xbps_api_impl.h"

/*
 * Verify shlib-{provides,requires} for packages in transaction.
 * This will catch cases where a package update would break its reverse
 * dependencies due to an incompatible SONAME bump:
 *
 * 	- foo-1.0 is installed and provides the 'libfoo.so.0' soname.
 * 	- foo-2.0 provides the 'libfoo.so.1' soname.
 * 	- baz-1.0 requires 'libfoo.so.0'.
 * 	- foo is updated to 2.0, hence baz-1.0 is now broken.
 *
 * Abort transaction if such case is found.
 */

static void
shlib_register(xbps_dictionary_t d, const char *shlib, const char *pkgver)
{
	xbps_array_t array;
	bool alloc = false;

	if ((array = xbps_dictionary_get(d, shlib)) == NULL) {
		alloc = true;
		array = xbps_array_create();
		xbps_dictionary_set(d, shlib, array);
	}
	if (!xbps_match_string_in_array(array, pkgver))
		xbps_array_add_cstring_nocopy(array, pkgver);
	if (alloc)
		xbps_object_release(array);
}

static xbps_dictionary_t
collect_shlibs(struct xbps_handle *xhp, xbps_array_t pkgs, bool req)
{
	xbps_object_t obj;
	xbps_object_iterator_t iter;
	xbps_dictionary_t d, pd;
	const char *pkgname, *pkgver;

	d = xbps_dictionary_create();
	assert(d);

	/* copy pkgdb to out temporary dictionary */
	pd = xbps_dictionary_copy(xhp->pkgdb);
	assert(pd);

	/*
	 * copy pkgs from transaction to our dictionary, overriding them
	 * if they were there from pkgdb.
	 */
	iter = xbps_array_iterator(pkgs);
	assert(iter);
	while ((obj = xbps_object_iterator_next(iter))) {
		if (!xbps_dictionary_get_cstring_nocopy(obj, "pkgname", &pkgname))
			continue;

		/* ignore shlibs if pkg is on hold mode */
		if (xbps_transaction_pkg_type(obj) == XBPS_TRANS_HOLD) {
			continue;
		}

		xbps_dictionary_set(pd, pkgname, obj);
	}
	xbps_object_iterator_release(iter);

	/*
	 * iterate over our dictionary to collect shlib-{requires,provides}.
	 */
	iter = xbps_dictionary_iterator(pd);
	assert(iter);

	while ((obj = xbps_object_iterator_next(iter))) {
		xbps_array_t shobjs;
		xbps_dictionary_t pkgd;

		pkgd = xbps_dictionary_get_keysym(pd, obj);
		if (xbps_transaction_pkg_type(pkgd) == XBPS_TRANS_REMOVE) {
			continue;
		}
		/*
		 * If pkg does not have the required obj, pass to next one.
		 */
		xbps_dictionary_get_cstring_nocopy(pkgd, "pkgver", &pkgver);
		shobjs = xbps_dictionary_get(pkgd,
				req ? "shlib-requires" : "shlib-provides");
		if (shobjs == NULL)
			continue;

		for (unsigned int i = 0; i < xbps_array_count(shobjs); i++) {
			const char *shlib = NULL;

			xbps_array_get_cstring_nocopy(shobjs, i, &shlib);
			xbps_dbg_printf(xhp, "%s: registering %s for %s\n",
			    pkgver, shlib, req ? "shlib-requires" : "shlib-provides");
			if (req)
				shlib_register(d, shlib, pkgver);
			else
				xbps_dictionary_set_cstring_nocopy(d, shlib, pkgver);
		}
	}
	xbps_object_iterator_release(iter);
	xbps_object_release(pd);
	return d;
}

bool HIDDEN
xbps_transaction_check_shlibs(struct xbps_handle *xhp, xbps_array_t pkgs)
{
	xbps_array_t array, mshlibs;
	xbps_object_t obj, obj2;
	xbps_object_iterator_t iter;
	xbps_dictionary_t shrequires, shprovides;
	const char *pkgver = NULL, *shlib = NULL;
	char *buf;
	bool broken = false;

	shrequires = collect_shlibs(xhp, pkgs, true);
	shprovides = collect_shlibs(xhp, pkgs, false);

	mshlibs = xbps_dictionary_get(xhp->transd, "missing_shlibs");
	/* iterate over shlib-requires to find unmatched shlibs */
	iter = xbps_dictionary_iterator(shrequires);
	assert(iter);

	while ((obj = xbps_object_iterator_next(iter))) {
		shlib = xbps_dictionary_keysym_cstring_nocopy(obj);
		xbps_dbg_printf(xhp, "%s: checking for `%s': ", __func__, shlib);
		if ((obj2 = xbps_dictionary_get(shprovides, shlib))) {
			xbps_dbg_printf_append(xhp, "provided by `%s'\n",
			    xbps_string_cstring_nocopy(obj2));
			continue;
		}
		xbps_dbg_printf_append(xhp, "not found\n");

		broken = true;
		array = xbps_dictionary_get_keysym(shrequires, obj);
		for (unsigned int i = 0; i < xbps_array_count(array); i++) {
			xbps_array_get_cstring_nocopy(array, i, &pkgver);
			buf = xbps_xasprintf("%s: broken, unresolvable "
			    "shlib `%s'", pkgver, shlib);
			xbps_array_add_cstring(mshlibs, buf);
			free(buf);
		}
	}
	xbps_object_iterator_release(iter);
	if (!broken) {
		xbps_dictionary_remove(xhp->transd, "missing_shlibs");
	}
	xbps_object_release(shprovides);
	xbps_object_release(shrequires);

	return true;
}