/*-
 * Copyright (c) 2008-2012 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 <sys/stat.h>
#include <stdio.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <libgen.h>

#include "xbps_api_impl.h"

static int
set_extract_flags(void)
{
	int flags;

	if (geteuid() == 0)
		flags = FEXTRACT_FLAGS;
	else
		flags = EXTRACT_FLAGS;

	return flags;
}

static int
extract_metafile(struct xbps_handle *xhp,
		 struct archive *ar,
		 struct archive_entry *entry,
		 const char *file,
		 const char *pkgver,
		 bool exec,
		 int flags)
{
	const char *version;
	char *buf, *dirc, *dname, *pkgname;
	int rv;

	pkgname = xbps_pkg_name(pkgver);
	if (pkgname == NULL)
		return ENOMEM;
	version = xbps_pkg_version(pkgver);
	if (version == NULL) {
		free(pkgname);
		return ENOMEM;
	}
	buf = xbps_xasprintf("%s/metadata/%s/%s",
	    XBPS_META_PATH, pkgname, file);
	if (buf == NULL) {
		free(pkgname);
		return ENOMEM;
	}
	archive_entry_set_pathname(entry, buf);
	dirc = strdup(buf);
	if (dirc == NULL) {
		free(buf);
		free(pkgname);
		return ENOMEM;
	}
	free(buf);
	dname = dirname(dirc);
	if (access(dname, X_OK) == -1) {
		if (xbps_mkpath(dname, 0755) == -1) {
			xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
			    errno, pkgname, version,
			    "%s: [unpack] failed to create metadir `%s': %s",
			    pkgver, dname, strerror(errno));
			free(dirc);
			free(pkgname);
			return errno;

		}
	}
	if (exec)
		archive_entry_set_perm(entry, 0750);

	if (archive_read_extract(ar, entry, flags) != 0) {
		rv = archive_errno(ar);
		xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
		    rv, pkgname, version,
		    "%s: [unpack] failed to extract metafile `%s': %s",
		    pkgver, file, strerror(rv));
		free(dirc);
		free(pkgname);
		return rv;
	}
	free(pkgname);
	free(dirc);

	return 0;
}

static int
remove_metafile(struct xbps_handle *xhp,
		const char *file,
		const char *pkgver)
{
	const char *version;
	char *buf, *pkgname;

	pkgname = xbps_pkg_name(pkgver);
	if (pkgname == NULL)
		return ENOMEM;
	version = xbps_pkg_version(pkgver);
	if (version == NULL) {
		free(pkgname);
		return ENOMEM;
	}
	buf = xbps_xasprintf("%s/metadata/%s/%s",
	    XBPS_META_PATH, pkgname, file);
	if (buf == NULL) {
		free(pkgname);
		return ENOMEM;
	}
	if (unlink(buf) == -1) {
		if (errno && errno != ENOENT) {
			xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
			    errno, pkgname, version,
			    "%s: [unpack] failed to remove metafile `%s': %s",
			    pkgver, file, strerror(errno));
			free(pkgname);
			free(buf);
			return errno;
		}
	}
	free(buf);
	free(pkgname);

	return 0;
}

static int
unpack_archive(struct xbps_handle *xhp,
	       prop_dictionary_t pkg_repod,
	       struct archive *ar)
{
	prop_dictionary_t propsd = NULL, filesd = NULL, old_filesd = NULL;
	prop_array_t array;
	const struct stat *entry_statp;
	struct stat st;
	struct xbps_unpack_cb_data xucd;
	struct archive_entry *entry;
	size_t nmetadata = 0, entry_idx = 0;
	const char *entry_pname, *transact, *pkgname, *version, *pkgver, *fname;
	char *buf = NULL, *pkgfilesd = NULL;
	size_t i, x;
	int ar_rv, rv, flags;
	bool preserve, update, conf_file, file_exists, skip_obsoletes;
	bool softreplace;

	assert(prop_object_type(pkg_repod) == PROP_TYPE_DICTIONARY);
	assert(ar != NULL);

	preserve = update = conf_file = file_exists = false;
	skip_obsoletes = softreplace = false;

	prop_dictionary_get_bool(pkg_repod, "preserve", &preserve);
	prop_dictionary_get_bool(pkg_repod, "skip-obsoletes", &skip_obsoletes);
	prop_dictionary_get_bool(pkg_repod, "softreplace", &softreplace);
	prop_dictionary_get_cstring_nocopy(pkg_repod,
	    "transaction", &transact);
	prop_dictionary_get_cstring_nocopy(pkg_repod, "pkgname", &pkgname);
	prop_dictionary_get_cstring_nocopy(pkg_repod, "version", &version);
	prop_dictionary_get_cstring_nocopy(pkg_repod, "pkgver", &pkgver);
	prop_dictionary_get_cstring_nocopy(pkg_repod, "filename", &fname);

	if (xhp->unpack_cb != NULL) {
		/* initialize data for unpack cb */
		memset(&xucd, 0, sizeof(xucd));
	}
	if (access(xhp->rootdir, R_OK) == -1) {
		if (errno != ENOENT) {
			rv = errno;
			goto out;
		}
		if (xbps_mkpath(xhp->rootdir, 0750) == -1) {
			rv = errno;
			goto out;
		}
	}
	if (chdir(xhp->rootdir) == -1) {
		xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
		    errno, pkgname, version,
		    "%s: [unpack] failed to chdir to rootdir `%s': %s",
		    pkgver, xhp->rootdir, strerror(errno));
		rv = errno;
		goto out;
	}
	if (strcmp(transact, "update") == 0)
		update = true;
	/*
	 * Always remove current INSTALL/REMOVE scripts in pkg's metadir,
	 * as security measures.
	 */
	if ((rv = remove_metafile(xhp, "INSTALL", pkgver)) != 0)
		goto out;
	if ((rv = remove_metafile(xhp, "REMOVE", pkgver)) != 0)
		goto out;

	/*
	 * Process the archive files.
	 */
	for (;;) {
		ar_rv = archive_read_next_header(ar, &entry);
		if (ar_rv == ARCHIVE_EOF || ar_rv == ARCHIVE_FATAL)
			break;
		else if (ar_rv == ARCHIVE_RETRY)
			continue;

		entry_statp = archive_entry_stat(entry);
		entry_pname = archive_entry_pathname(entry);
		flags = set_extract_flags();
		/*
		 * Ignore directories from archive.
		 */
		if (S_ISDIR(entry_statp->st_mode)) {
			archive_read_data_skip(ar);
			continue;
		}
		/*
		 * Prepare unpack callback ops.
		 */
		if (xhp->unpack_cb != NULL) {
			xucd.pkgver = pkgver;
			xucd.entry = entry_pname;
			xucd.entry_size = archive_entry_size(entry);
			xucd.entry_is_conf = false;
		}
		if (strcmp("./INSTALL", entry_pname) == 0) {
			/*
			 * Extract the INSTALL script first to execute
			 * the pre install target.
			 */
			buf = xbps_xasprintf("%s/metadata/%s/INSTALL",
			    XBPS_META_PATH, pkgname);
			if (buf == NULL) {
				rv = ENOMEM;
				goto out;
			}
			rv = extract_metafile(xhp, ar, entry,
			    "INSTALL", pkgver, true, flags);
			if (rv != 0)
				goto out;

			rv = xbps_file_exec(xhp, buf, "pre",
			     pkgname, version, update ? "yes" : "no",
			     xhp->conffile, NULL);
			free(buf);
			buf = NULL;
			if (rv != 0) {
				xbps_set_cb_state(xhp,
				    XBPS_STATE_UNPACK_FAIL,
				    rv, pkgname, version,
				    "%s: [unpack] INSTALL script failed "
				    "to execute pre ACTION: %s",
				    pkgver, strerror(rv));
				goto out;
			}
			nmetadata++;
			continue;

		} else if (strcmp("./REMOVE", entry_pname) == 0) {
			rv = extract_metafile(xhp, ar, entry,
			    "REMOVE", pkgver, true, flags);
			if (rv != 0)
				goto out;

			nmetadata++;
			continue;

		} else if (strcmp("./files.plist", entry_pname) == 0) {
			/*
			 * Internalize this entry into a prop_dictionary
			 * to check for obsolete files if updating a package.
			 * It will be extracted to disk at the end.
			 */
			filesd = xbps_dictionary_from_archive_entry(ar, entry);
			if (filesd == NULL) {
				rv = errno;
				goto out;
			}
			nmetadata++;
			continue;

		} else if (strcmp("./props.plist", entry_pname) == 0) {
			rv = extract_metafile(xhp, ar, entry, XBPS_PKGPROPS,
			    pkgver, false, flags);
			if (rv != 0)
				goto out;

			propsd = xbps_dictionary_from_metadata_plist(xhp,
			    pkgname, XBPS_PKGPROPS);
			if (propsd == NULL) {
				rv = errno;
				goto out;
			}
			nmetadata++;
			continue;
		}
		/*
		 * If XBPS_PKGFILES or XBPS_PKGPROPS weren't found
		 * in the archive at this phase, skip all data.
		 */
		if (propsd == NULL || filesd == NULL) {
			archive_read_data_skip(ar);
			/*
			 * If we have processed 4 entries and the two
			 * required metadata files weren't found, bail out.
			 * This is not an XBPS binary package.
			 */
			if (entry_idx >= 3) {
				xbps_set_cb_state(xhp,
				    XBPS_STATE_UNPACK_FAIL,
				    ENODEV, pkgname, version,
				    "%s: [unpack] invalid binary package `%s'.",
				    pkgver, fname);
				rv = ENODEV;
				goto out;
			}

			entry_idx++;
			continue;
		}
		/*
		 * Compute total entries in progress data, if set.
		 * total_entries = files + conf_files + links.
		 */
		if (xhp->unpack_cb != NULL) {
			xucd.entry_total_count = 0;
			array = prop_dictionary_get(filesd, "files");
			xucd.entry_total_count +=
			    (ssize_t)prop_array_count(array);
			array = prop_dictionary_get(filesd, "conf_files");
			xucd.entry_total_count +=
			    (ssize_t)prop_array_count(array);
			array = prop_dictionary_get(filesd, "links");
			xucd.entry_total_count +=
			    (ssize_t)prop_array_count(array);
		}
		/*
		 * Always check that extracted file exists and hash
		 * doesn't match, in that case overwrite the file.
		 * Otherwise skip extracting it.
		 */
		conf_file = false;
		file_exists = false;
		if (S_ISREG(entry_statp->st_mode)) {
			if (xbps_entry_is_a_conf_file(propsd, entry_pname))
				conf_file = true;
			if (stat(entry_pname, &st) == 0) {
				/* remove first char, i.e '.' */
				buf = strdup(entry_pname);
				assert(buf != NULL);
				for (i = 1, x = 0; i < strlen(entry_pname); x++, i++)
					buf[x] = entry_pname[i];
				buf[x] = '\0';
				file_exists = true;
				rv = xbps_file_hash_check_dictionary(xhp, filesd,
				    conf_file ? "conf_files" : "files", buf);
				free(buf);

				if (rv == -1) {
					/* error */
					xbps_dbg_printf(xhp,
					    "%s-%s: failed to check"
					    " hash for `%s': %s\n", pkgname,
					    version, entry_pname,
					    strerror(errno));
					goto out;
				} else if (rv == 0) {
					/*
					 * Always set entry perms in existing
					 * file, even when hash is matched.
					 */
					if (chmod(entry_pname,
					    entry_statp->st_mode) != 0) {
						xbps_dbg_printf(xhp,
						    "%s-%s: failed "
						    "to set perms %s to %s: %s\n",
						    pkgname, version,
						    archive_entry_strmode(entry),
						    entry_pname,
						    strerror(errno));
						rv = EINVAL;
						goto out;
					}
					xbps_dbg_printf(xhp,
					    "%s-%s: entry %s perms "
					    "to %s.\n", pkgname, version,
					    entry_pname,
					    archive_entry_strmode(entry));
					/*
					 * hash match, skip extraction.
					 */
					xbps_dbg_printf(xhp,
					    "%s-%s: entry %s "
					    "matches current SHA256, "
					    "skipping...\n", pkgname,
					    version, entry_pname);
					archive_read_data_skip(ar);
					continue;
				}
			}
		}
		if (!update && conf_file && file_exists) {
			/*
			 * If installing new package preserve old configuration
			 * file but renaming it to <file>.old.
			 */
			buf = xbps_xasprintf("%s.old", entry_pname);
			if (buf == NULL) {
				rv = ENOMEM;
				goto out;
			}
			(void)rename(entry_pname, buf);
			free(buf);
			buf = NULL;
			xbps_set_cb_state(xhp,
			    XBPS_STATE_CONFIG_FILE, 0,
			    pkgname, version,
			    "Renamed old configuration file "
			    "`%s' to `%s.old'.", entry_pname, entry_pname);
		} else if (update && conf_file && file_exists) {
			/*
			 * Handle configuration files. Check if current entry is
			 * a configuration file and take action if required. Skip
			 * packages that don't have the "conf_files" array in
			 * the XBPS_PKGPROPS dictionary.
			 */
			if (xhp->unpack_cb != NULL)
				xucd.entry_is_conf = true;

			rv = xbps_entry_install_conf_file(xhp, filesd,
			    entry, entry_pname, pkgname, version);
			if (rv == -1) {
				/* error */
				goto out;
			} else if (rv == 0) {
				/*
				 * Keep current configuration file
				 * as is now and pass to next entry.
				 */
				archive_read_data_skip(ar);
				continue;
			}
			/*
			 * Reset entry_pname again because if entry's pathname
			 * has been changed it will become a dangling pointer.
			 */
			entry_pname = archive_entry_pathname(entry);
		}
		/*
		 * Extract entry from archive.
		 */
		if (archive_read_extract(ar, entry, flags) != 0) {
			rv = archive_errno(ar);
			xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
			    rv, pkgname, version,
			    "%s: [unpack] failed to extract file `%s': %s",
			    pkgver, entry_pname, strerror(rv));
		}
		if (xhp->unpack_cb != NULL) {
			xucd.entry_extract_count++;
			(*xhp->unpack_cb)(xhp, &xucd, xhp->unpack_cb_data);
		}
	}
	/*
	 * If there was any error extracting files from archive, error out.
	 */
	if ((rv = archive_errno(ar)) != 0) {
		xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
		    rv, pkgname, version,
		    "%s: [unpack] failed to extract files: %s",
		    pkgver, fname, archive_error_string(ar));
		goto out;
	}
	/*
	 * Skip checking for obsolete files on:
	 * 	- New package installation without "softreplace" keyword.
	 * 	- Package with "preserve" keyword.
	 * 	- Package with "skip-obsoletes" keyword.
	 */
	pkgfilesd = xbps_xasprintf("%s/metadata/%s/%s",
	    XBPS_META_PATH, pkgname, XBPS_PKGFILES);
	if (pkgfilesd == NULL) {
		rv = ENOMEM;
		goto out;
	}
	if (skip_obsoletes || preserve || (!softreplace && !update))
		goto out1;
	/*
	 * Check for obsolete files on:
	 * 	- Package upgrade.
	 * 	- Package with "softreplace" keyword.
	 */
	old_filesd = prop_dictionary_internalize_from_zfile(pkgfilesd);
	if (prop_object_type(old_filesd) == PROP_TYPE_DICTIONARY) {
		rv = xbps_remove_obsoletes(xhp, pkgname, version,
		    pkgver, old_filesd, filesd);
		prop_object_release(old_filesd);
		if (rv != 0) {
			rv = errno;
			goto out;
		}
	} else if (errno && errno != ENOENT) {
		rv = errno;
		goto out;
	}
out1:
	/*
	 * Create pkg metadata directory.
	 */
	buf = xbps_xasprintf("%s/metadata/%s", XBPS_META_PATH, pkgname);
	if (buf == NULL) {
		rv = ENOMEM;
		goto out;
	}
	if (xbps_mkpath(buf, 0755) == -1) {
		xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
		    errno, pkgname, version,
		    "%s: [unpack] failed to create pkg metadir `%s': %s",
		    buf, pkgver, strerror(errno));
		rv = errno;
		goto out;
	}
	/*
	 * Externalize XBPS_PKGFILES into pkg metadata directory.
	 */
	if (!prop_dictionary_externalize_to_zfile(filesd, pkgfilesd)) {
		rv = errno;
		xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
		    errno, pkgname, version,
		    "%s: [unpack] failed to extract metadata file `%s': %s",
		    pkgver, XBPS_PKGFILES, strerror(errno));
		goto out;
	}
out:
	if (xucd != NULL)
		free(xucd);
	if (pkgfilesd != NULL)
		free(pkgfilesd);
	if (buf != NULL)
		free(buf);
	if (prop_object_type(filesd) == PROP_TYPE_DICTIONARY)
		prop_object_release(filesd);
	if (prop_object_type(propsd) == PROP_TYPE_DICTIONARY)
		prop_object_release(propsd);

	return rv;
}

int HIDDEN
xbps_unpack_binary_pkg(struct xbps_handle *xhp, prop_dictionary_t pkg_repod)
{
	struct archive *ar = NULL;
	const char *pkgname, *version, *repoloc, *pkgver, *fname;
	char *bpkg = NULL;
	int rv = 0;

	assert(prop_object_type(pkg_repod) == PROP_TYPE_DICTIONARY);

	prop_dictionary_get_cstring_nocopy(pkg_repod, "pkgname", &pkgname);
	prop_dictionary_get_cstring_nocopy(pkg_repod, "version", &version);
	prop_dictionary_get_cstring_nocopy(pkg_repod, "pkgver", &pkgver);
	prop_dictionary_get_cstring_nocopy(pkg_repod, "repository", &repoloc);
	prop_dictionary_get_cstring_nocopy(pkg_repod, "filename", &fname);

	xbps_set_cb_state(xhp, XBPS_STATE_UNPACK, 0, pkgname, version, NULL);

	bpkg = xbps_path_from_repository_uri(xhp, pkg_repod, repoloc);
	if (bpkg == NULL) {
		xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
		    errno, pkgname, version,
		    "%s: [unpack] cannot determine binary package "
		    "file for `%s': %s", pkgver, fname, strerror(errno));
		return errno;
	}

	if ((ar = archive_read_new()) == NULL) {
		free(bpkg);
		return ENOMEM;
	}
	/*
	 * Enable support for tar format and gzip/bzip2/lzma compression methods.
	 */
	archive_read_support_compression_gzip(ar);
	archive_read_support_compression_bzip2(ar);
	archive_read_support_compression_xz(ar);
	archive_read_support_format_tar(ar);

	if (archive_read_open_filename(ar, bpkg, ARCHIVE_READ_BLOCKSIZE) != 0) {
		rv = archive_errno(ar);
		xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
		    rv, pkgname, version,
		    "%s: [unpack] failed to open binary package `%s': %s",
		    pkgver, fname, strerror(rv));
		free(bpkg);
		archive_read_free(ar);
		return rv;
	}
	free(bpkg);

	/*
	 * Set package state to half-unpacked.
	 */
	if ((rv = xbps_set_pkg_state_installed(xhp, pkgname, version,
	    XBPS_PKG_STATE_HALF_UNPACKED)) != 0) {
		xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
		    rv, pkgname, version,
		    "%s: [unpack] failed to set state to half-unpacked: %s",
		    pkgver, strerror(rv));
		goto out;
	}
	/*
	 * Extract archive files.
	 */
	if ((rv = unpack_archive(xhp, pkg_repod, ar)) != 0) {
		xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
		    rv, pkgname, version,
		    "%s: [unpack] failed to unpack files from archive: %s",
		    pkgver, strerror(rv));
		goto out;
	}
	/*
	 * Set package state to unpacked.
	 */
	if ((rv = xbps_set_pkg_state_installed(xhp, pkgname, version,
	    XBPS_PKG_STATE_UNPACKED)) != 0) {
		xbps_set_cb_state(xhp, XBPS_STATE_UNPACK_FAIL,
		    rv, pkgname, version,
		    "%s: [unpack] failed to set state to unpacked: %s",
		    pkgver, strerror(rv));
	}
out:
	if (ar) {
		archive_read_close(ar);
		archive_read_free(ar);
	}
	return rv;
}