#define FUSE_USE_VERSION 26

#include <sys/types.h>
#include <sqlite3.h>
#include <pthread.h>
#include <string.h>
#include <stdarg.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>

#else
#define APPFS_DEBUG(x...) /**/
#endif

static pthread_key_t interpKey;

struct appfs_thread_data {
	sqlite3 *db;
	const char *cachedir;
	time_t boottime;
	const char *platform;
	struct {
		int writable;
	} options;
};

struct appfs_thread_data globalThread;

		struct {
			off_t size;
			char source[256];
		} symlink;
	} typeinfo;
};

struct appfs_sqlite3_query_cb_handle {
	struct appfs_children *head;
	int argc;
	const char *fmt;
};

static Tcl_Interp *appfs_create_TclInterp(const char *cachedir) {
	Tcl_Interp *interp;
	int tcl_ret;

	APPFS_DEBUG("Creating new Tcl interpreter for TID = 0x%llx", (unsigned long long) pthread_self());

	interp = Tcl_CreateInterp();

	}

	tcl_ret = Tcl_Eval(interp, "package ifneeded sha1 1.0 [list load {} sha1]");
	if (tcl_ret != TCL_OK) {
		fprintf(stderr, "Unable to initialize Tcl SHA1.  Aborting.\n");
		fprintf(stderr, "Tcl Error is: %s\n", Tcl_GetStringResult(interp));











		Tcl_DeleteInterp(interp);

		return(NULL);
	}

	tcl_ret = Tcl_Eval(interp, ""
#include "appfsd.tcl.h"

		return;
	}

	return;
}

#define appfs_free_list_type(id, type) static void appfs_free_list_ ## id(type *head) { \
	type *obj, *next; \
	for (obj = head; obj; obj = next) { \
		next = obj->_next; \
		ckfree((void *) obj); \
	} \
}

appfs_free_list_type(children, struct appfs_children)

static uid_t appfs_get_fsuid(void) {
	struct fuse_context *ctx;

	ctx = fuse_get_context();
	if (ctx == NULL) {
		return(1);
	}

	return(ctx->uid);
}

static const char *appfs_get_homedir(uid_t fsuid) {
	struct passwd entry, *result;
	struct stat stbuf;
	char buf[1024], *retval;
	int gpu_ret, stat_ret;

	gpu_ret = getpwuid_r(fsuid, &entry, buf, sizeof(buf), &result);
	if (gpu_ret != 0) {

		    result->pw_dir,
		    (unsigned long long) stbuf.st_uid
		);

		return(NULL);
	}

	retval = sqlite3_mprintf("%s", result->pw_dir);

	return(retval);
}

static int appfs_getpackage_name_cb(void *_package_name, int columns, char **values, char **names) {
	char **package_name;

	if (columns != 1) {
		return(1);
	}

	package_name = _package_name;

	*package_name = sqlite3_mprintf("%s", values[0]);

	return(0);
}

static char *appfs_getpackage_name(const char *hostname, const char *package_hash) {
	char *sql;
	int sqlite_ret;
	char *package_name = NULL;

	sql = sqlite3_mprintf("SELECT package FROM packages WHERE hostname = %Q AND sha1 = %Q LIMIT 1;", hostname, package_hash);
	if (sql == NULL) {
		APPFS_DEBUG("Call to sqlite3_mprintf failed.");

		return(sqlite3_mprintf("%s", "unknown-package-name"));
	}
	sqlite_ret = sqlite3_exec(globalThread.db, sql, appfs_getpackage_name_cb, &package_name, NULL);
	sqlite3_free(sql);

	if (sqlite_ret != SQLITE_OK) {
		APPFS_DEBUG("Call to sqlite3_exec failed.");

		return(sqlite3_mprintf("%s", "unknown-package-name"));
	}

	return(package_name);
}

static struct appfs_children *appfs_getchildren_fs(struct appfs_children *in_children, const char *fspath) {
	APPFS_DEBUG("Searching %s", fspath);

	return(in_children);
}

static int appfs_getchildren_cb(void *_head, int columns, char **values, char **names) {
	struct appfs_children **head_p, *obj;

	head_p = _head;

	obj = (void *) ckalloc(sizeof(*obj));

	snprintf(obj->name, sizeof(obj->name), "%s", values[0]);

	if (*head_p == NULL) {
		obj->counter = 0;
	} else {
		obj->counter = (*head_p)->counter + 1;
	}

	obj->_next = *head_p;
	*head_p = obj;

	return(0);
	
}

static struct appfs_children *appfs_getchildren(const char *hostname, const char *package_hash, const char *path, int *children_count_p) {
	struct appfs_children *head = NULL;
	char *sql, *filebuf, *homedir = NULL;
	int sqlite_ret;
	uid_t fsuid;

	if (children_count_p == NULL) {
		return(NULL);
	}

	appfs_update_index(hostname);
	appfs_update_manifest(hostname, package_hash);

	sql = sqlite3_mprintf("SELECT file_name FROM files WHERE package_sha1 = %Q AND file_directory = %Q;", package_hash, path);
	if (sql == NULL) {
		APPFS_DEBUG("Call to sqlite3_mprintf failed.");

		return(NULL);
	}

	APPFS_DEBUG("SQL: %s", sql);
	sqlite_ret = sqlite3_exec(globalThread.db, sql, appfs_getchildren_cb, &head, NULL);
	sqlite3_free(sql);

	if (sqlite_ret != SQLITE_OK) {
		APPFS_DEBUG("Call to sqlite3_exec failed.");

		appfs_free_list_children(head);

		return(NULL);
	}

	if (globalThread.options.writable) {
		/* Determine user of process accessing this file */
		fsuid = appfs_get_fsuid();

		/* Check filesystem paths for updated files */
		/** Check the global directory (/etc) **/
		filebuf = sqlite3_mprintf("/etc/appfs/%z@%s/%s", appfs_getpackage_name(hostname, package_hash), hostname, path);
		if (filebuf == NULL) {
			APPFS_DEBUG("Call to sqlite3_mprintf failed.");

			return(NULL);
		}

		head = appfs_getchildren_fs(head, filebuf);

		sqlite3_free(filebuf);

		/** Check the user's directory, if we are not root **/
		if (fsuid != 0) {
			homedir = (char *) appfs_get_homedir(fsuid);
		}

		if (homedir != NULL) {
			filebuf = sqlite3_mprintf("%z/.appfs/%z@%s/%s", homedir, appfs_getpackage_name(hostname, package_hash), hostname, path);

			if (filebuf == NULL) {
				APPFS_DEBUG("Call to sqlite3_mprintf failed.");

				return(NULL);
			}

			head = appfs_getchildren_fs(head, filebuf);

			sqlite3_free(filebuf);
		}
	}

	if (head != NULL) {
		*children_count_p = head->counter + 1;
	} else {
		*children_count_p = 0;
	}

	return(head);
}

static int appfs_sqlite3_query_cb(void *_cb_handle, int columns, char **values, char **names) {
	struct appfs_sqlite3_query_cb_handle *cb_handle;
	struct appfs_children *obj;

	cb_handle = _cb_handle;

	obj = (void *) ckalloc(sizeof(*obj));

	switch (cb_handle->argc) {
		case 1:
			snprintf(obj->name, sizeof(obj->name), cb_handle->fmt, values[0]);
			break;
		case 2:
			snprintf(obj->name, sizeof(obj->name), cb_handle->fmt, values[0], values[1]);
			break;
		case 3:
			snprintf(obj->name, sizeof(obj->name), cb_handle->fmt, values[0], values[1], values[2]);
			break;
		case 4:
			snprintf(obj->name, sizeof(obj->name), cb_handle->fmt, values[0], values[1], values[2], values[3]);
			break;
	}

	if (cb_handle->head == NULL) {
		obj->counter = 0;
	} else {
		obj->counter = cb_handle->head->counter + 1;
	}

	obj->_next = cb_handle->head;
	cb_handle->head = obj;

	return(0);
}

static struct appfs_children *appfs_sqlite3_query(char *sql, int argc, const char *fmt, int *results_count_p) {
	struct appfs_sqlite3_query_cb_handle cb_handle;
	int sqlite_ret;

	if (results_count_p == NULL) {
		return(NULL);
	}

	if (sql == NULL) {
		APPFS_DEBUG("Call to sqlite3_mprintf probably failed.");

		return(NULL);
	}

	if (fmt == NULL) {
		fmt = "%s";
	}

	cb_handle.head = NULL;
	cb_handle.argc = argc;
	cb_handle.fmt  = fmt;

	APPFS_DEBUG("SQL: %s", sql);
	sqlite_ret = sqlite3_exec(globalThread.db, sql, appfs_sqlite3_query_cb, &cb_handle, NULL);
	sqlite3_free(sql);

	if (sqlite_ret != SQLITE_OK) {
		APPFS_DEBUG("Call to sqlite3_exec failed.");

		return(NULL);
	}

	if (cb_handle.head != NULL) {
		*results_count_p = cb_handle.head->counter + 1;
	}

	return(cb_handle.head);
}

static int appfs_lookup_package_hash_cb(void *_retval, int columns, char **values, char **names) {
	char **retval = _retval;

	*retval = strdup(values[0]);

	return(0);
}

static char *appfs_lookup_package_hash(const char *hostname, const char *package, const char *os, const char *cpuArch, const char *version) {
	char *sql;
	char *retval = NULL;
	int sqlite_ret;

	appfs_update_index(hostname);

	sql = sqlite3_mprintf("SELECT sha1 FROM packages WHERE hostname = %Q AND package = %Q AND os = %Q AND cpuArch = %Q AND version = %Q;",
		hostname,
		package,
		os,
		cpuArch,
		version
	);
	if (sql == NULL) {
		APPFS_DEBUG("Call to sqlite3_mprintf failed.");

		return(NULL);
	}

	APPFS_DEBUG("SQL: %s", sql);
	sqlite_ret = sqlite3_exec(globalThread.db, sql, appfs_lookup_package_hash_cb, &retval, NULL);
	sqlite3_free(sql);

	if (sqlite_ret != SQLITE_OK) {
		APPFS_DEBUG("Call to sqlite3_exec failed.");

		return(NULL);
	}

	return(retval);
}

static int appfs_getfileinfo_cb(void *_pathinfo, int columns, char **values, char **names) {
	struct appfs_pathinfo *pathinfo = _pathinfo;
	const char *type, *time, *source, *size, *perms, *sha1, *rowid;

	type = values[0];
	time = values[1];
	source = values[2];
	size = values[3];
	perms = values[4];
	sha1 = values[5];
	rowid = values[6];

	pathinfo->time = strtoull(time, NULL, 10);

	/* Package file inodes start at 2^32, fake inodes are before then */
	pathinfo->inode = strtoull(rowid, NULL, 10) + 4294967296ULL;

	if (strcmp(type, "file") == 0) {
		pathinfo->type = APPFS_PATHTYPE_FILE;

		if (!size) {
			size = "0";
		}

		if (!perms) {
			perms = "";
		}

		if (!sha1) {
			sha1 = "";
		}

		pathinfo->typeinfo.file.size = strtoull(size, NULL, 10);
		snprintf(pathinfo->typeinfo.file.sha1, sizeof(pathinfo->typeinfo.file.sha1), "%s", sha1);

		if (strcmp(perms, "x") == 0) {
			pathinfo->typeinfo.file.executable = 1;
		} else {
			pathinfo->typeinfo.file.executable = 0;
		}

		return(0);
	}

	if (strcmp(type, "directory") == 0) {
		pathinfo->type = APPFS_PATHTYPE_DIRECTORY;
		pathinfo->typeinfo.dir.childcount = 0;

		return(0);
	}

	if (strcmp(type, "symlink") == 0) {
		pathinfo->type = APPFS_PATHTYPE_SYMLINK;
		pathinfo->typeinfo.dir.childcount = 0;

		if (!source) {
			source = ".BADLINK";
		}

		pathinfo->typeinfo.symlink.size = strlen(source);
		snprintf(pathinfo->typeinfo.symlink.source, sizeof(pathinfo->typeinfo.symlink.source), "%s", source);

		return(0);
	}

	return(0);

	/* Until this is used, prevent the compiler from complaining */
	source = source;
}

static int appfs_getfileinfo(const char *hostname, const char *package_hash, const char *_path, struct appfs_pathinfo *pathinfo) {
	char *directory, *file, *path;
	char *sql;
	int sqlite_ret;

	if (pathinfo == NULL) {
		return(-EIO);
	}

	appfs_update_index(hostname);
	appfs_update_manifest(hostname, package_hash);

	path = strdup(_path);
	directory = path;
	file = strrchr(path, '/');
	if (file == NULL) {
		file = path;
		directory = "";
	} else {
		*file = '\0';
		file++;
	}

	sql = sqlite3_mprintf("SELECT type, time, source, size, perms, file_sha1, rowid FROM files WHERE package_sha1 = %Q AND file_directory = %Q AND file_name = %Q;", package_hash, directory, file);
	if (sql == NULL) {
		APPFS_DEBUG("Call to sqlite3_mprintf failed.");

		free(path);

		return(-EIO);
	}

	free(path);

	pathinfo->type = APPFS_PATHTYPE_INVALID;

	APPFS_DEBUG("SQL: %s", sql);
	sqlite_ret = sqlite3_exec(globalThread.db, sql, appfs_getfileinfo_cb, pathinfo, NULL);
	sqlite3_free(sql);

	if (sqlite_ret != SQLITE_OK) {
		APPFS_DEBUG("Call to sqlite3_exec failed.");

		return(-EIO);
	}

	if (pathinfo->type == APPFS_PATHTYPE_INVALID) {
		return(-ENOENT);
	}

	return(0);
}

static int appfs_get_path_info_sql(char *sql, int argc, const char *fmt, struct appfs_pathinfo *pathinfo, struct appfs_children **children) {
	struct appfs_children *node, *dir_children, *dir_child;
	int dir_children_count = 0;

	dir_children = appfs_sqlite3_query(sql, argc, fmt, &dir_children_count);

	if (dir_children == NULL || dir_children_count == 0) {
		return(-ENOENT);
	}

	/* Request for a single hostname */
	pathinfo->type = APPFS_PATHTYPE_DIRECTORY;
	pathinfo->typeinfo.dir.childcount = dir_children_count;
	pathinfo->time = globalThread.boottime;

	if (children) {
		for (dir_child = dir_children; dir_child; dir_child = dir_child->_next) {
			node = (void *) ckalloc(sizeof(*node));
			node->_next = *children;
			strcpy(node->name, dir_child->name);
			*children = node;
		}
	}

	appfs_free_list_children(dir_children);

	return(0);
}

static int appfs_add_path_child(const char *name, struct appfs_pathinfo *pathinfo, struct appfs_children **children) {
	struct appfs_children *new_child;

	pathinfo->typeinfo.dir.childcount++;

	if (children) {
		new_child = (void *) ckalloc(sizeof(*new_child));
		new_child->_next = *children;

		snprintf(new_child->name, sizeof(new_child->name), "%s", name);

		*children = new_child;
	}

	return(0);
}

/* Generate an inode for a given path */
static long long appfs_get_path_inode(const char *path) {
	long long retval;
	const char *p;

	retval %= 4294967296ULL;

	return(retval);
}

/* Get information about a path, and optionally list children */
static int appfs_get_path_info(const char *_path, struct appfs_pathinfo *pathinfo, struct appfs_children **children) {
	struct appfs_children *dir_children;
	char *hostname, *packagename, *os_cpuArch, *os, *cpuArch, *version;
	char *path, *path_s;
	char *package_hash;
	char *sql;
	int files_count;
	int fileinfo_ret, retval;

	/* Initialize return */
	if (children) {
		*children = NULL;
	}

	/* Verify that this is a valid request */
	if (_path == NULL) {
		return(-ENOENT);
	}

	if (_path[0] != '/') {
		return(-ENOENT);
	}

	/* Note that this is not a "real" directory from a package */
	pathinfo->packaged = 0;

	if (_path[1] == '\0') {
		/* Request for the root directory */
		pathinfo->hostname[0] = '\0';
		pathinfo->inode = 1;

		sql = sqlite3_mprintf("SELECT DISTINCT hostname FROM packages;");

		retval = appfs_get_path_info_sql(sql, 1, NULL, pathinfo, children);

		/* The root directory always exists, even if it has no subordinates */
		if (retval != 0) {
			pathinfo->type = APPFS_PATHTYPE_DIRECTORY;
			pathinfo->typeinfo.dir.childcount = 0;
			pathinfo->time = globalThread.boottime;

			retval = 0;
		}

		return(retval);
	}

	path = strdup(_path);
	path_s = path;

	pathinfo->inode = appfs_get_path_inode(path);

	hostname = path + 1;
	packagename = strchr(hostname, '/');

	if (packagename != NULL) {
		*packagename = '\0';
		packagename++;
	}

	snprintf(pathinfo->hostname, sizeof(pathinfo->hostname), "%s", hostname);

	if (packagename == NULL) {
		appfs_update_index(hostname);

		sql = sqlite3_mprintf("SELECT DISTINCT package FROM packages WHERE hostname = %Q;", hostname);

		free(path_s);

		return(appfs_get_path_info_sql(sql, 1, NULL, pathinfo, children));
	}

	os_cpuArch = strchr(packagename, '/');

	if (os_cpuArch != NULL) {
		*os_cpuArch = '\0';
		os_cpuArch++;
	}

	if (os_cpuArch == NULL) {
		appfs_update_index(hostname);

		sql = sqlite3_mprintf("SELECT DISTINCT os, cpuArch FROM packages WHERE hostname = %Q AND package = %Q;", hostname, packagename);

		free(path_s);

		retval = appfs_get_path_info_sql(sql, 2, "%s-%s", pathinfo, children);

		if (retval != 0) {
			return(retval);
		}

		appfs_add_path_child("platform", pathinfo, children);

		return(retval);
	}

	version = strchr(os_cpuArch, '/');

	if (version != NULL) {
		*version = '\0';
		version++;
	}

	os = os_cpuArch;
	cpuArch = strchr(os_cpuArch, '-');
	if (cpuArch) {
		*cpuArch = '\0';
		cpuArch++;
	} else {
		cpuArch = "";
	}

	if (version == NULL) {
		if (strcmp(os, "platform") == 0 && strcmp(cpuArch, "") == 0) {
			pathinfo->type = APPFS_PATHTYPE_SYMLINK;
			pathinfo->time = globalThread.boottime;
			pathinfo->typeinfo.dir.childcount = 0;
			pathinfo->typeinfo.symlink.size = strlen(globalThread.platform);

			snprintf(pathinfo->typeinfo.symlink.source, sizeof(pathinfo->typeinfo.symlink.source), "%s", globalThread.platform);

			free(path_s);

			return(0);
		}

		/* Request for version list for a package on an OS/CPU */
		appfs_update_index(hostname);

		sql = sqlite3_mprintf("SELECT DISTINCT version FROM packages WHERE hostname = %Q AND package = %Q AND os = %Q and cpuArch = %Q;", hostname, packagename, os, cpuArch);

		free(path_s);

		return(appfs_get_path_info_sql(sql, 1, NULL, pathinfo, children));
	}

	path = strchr(version, '/');
	if (path == NULL) {
		path = "";
	} else {
		*path = '\0';
		path++;
	}

	/* Request for a file in a specific package */
	pathinfo->packaged = 1;
	APPFS_DEBUG("Requesting information for hostname = %s, package = %s, os = %s, cpuArch = %s, version = %s, path = %s", 
		hostname, packagename, os, cpuArch, version, path
	);

	package_hash = appfs_lookup_package_hash(hostname, packagename, os, cpuArch, version);
	if (package_hash == NULL) {
		free(path_s);

		return(-ENOENT);
	}

	APPFS_DEBUG("  ... which hash a hash of %s", package_hash);

	appfs_update_manifest(hostname, package_hash);

	if (strcmp(path, "") == 0) {
		pathinfo->type = APPFS_PATHTYPE_DIRECTORY;
		pathinfo->time = globalThread.boottime;
	} else {
		fileinfo_ret = appfs_getfileinfo(hostname, package_hash, path, pathinfo);
		if (fileinfo_ret != 0) {
			free(path_s);

			return(fileinfo_ret);
		}
	}

	if (pathinfo->type == APPFS_PATHTYPE_DIRECTORY) {
		dir_children = appfs_getchildren(hostname, package_hash, path, &files_count);

		if (dir_children != NULL) {
			pathinfo->typeinfo.dir.childcount = files_count;
		}

		if (children) {
			*children = dir_children;
		} else {
			appfs_free_list_children(dir_children);
		}
	}

	free(path_s);

	return(0);
}

static int appfs_fuse_readlink(const char *path, char *buf, size_t size) {
	struct appfs_pathinfo pathinfo;
	int res = 0;

	APPFS_DEBUG("Enter (path = %s, ...)", path);

	pathinfo.type = APPFS_PATHTYPE_INVALID;

	res = appfs_get_path_info(path, &pathinfo, NULL);
	if (res != 0) {
		return(res);
	}

	if (pathinfo.type != APPFS_PATHTYPE_SYMLINK) {
		return(-EINVAL);
	}

	if ((strlen(pathinfo.typeinfo.symlink.source) + 1) > size) {
		return(-ENAMETOOLONG);
	}

	memcpy(buf, pathinfo.typeinfo.symlink.source, strlen(pathinfo.typeinfo.symlink.source) + 1);

	return(0);
}

static int appfs_fuse_getattr(const char *path, struct stat *stbuf) {
	struct appfs_pathinfo pathinfo;
	int res = 0;

	APPFS_DEBUG("Enter (path = %s, ...)", path);

	.getattr   = appfs_fuse_getattr,
	.readdir   = appfs_fuse_readdir,
	.readlink  = appfs_fuse_readlink,
	.open      = appfs_fuse_open,
	.release   = appfs_fuse_close,
	.read      = appfs_fuse_read
};















int main(int argc, char **argv) {
	const char *cachedir = APPFS_CACHEDIR;
	char dbfilename[1024];
	int pthread_ret, snprintf_ret, sqlite_ret;

	globalThread.cachedir = cachedir;
	globalThread.boottime = time(NULL);
	globalThread.platform = "linux-x86_64";
	globalThread.options.writable = 1;

	Tcl_StaticPackage(NULL, "sha1", Sha1_Init, NULL);


	pthread_ret = pthread_key_create(&interpKey, NULL);
	if (pthread_ret != 0) {
		fprintf(stderr, "Unable to create TSD key for Tcl.  Aborting.\n");

		return(1);
	}

	snprintf_ret = snprintf(dbfilename, sizeof(dbfilename), "%s/%s", cachedir, "cache.db");
	if (snprintf_ret >= sizeof(dbfilename)) {
		fprintf(stderr, "Unable to set database filename.  Aborting.\n");

		return(1);
	}

	sqlite_ret = sqlite3_open(dbfilename, &globalThread.db);
	if (sqlite_ret != SQLITE_OK) {
		fprintf(stderr, "Unable to open database: %s\n", dbfilename);

		return(1);
	}

	return(fuse_main(argc, argv, &appfs_oper, NULL));
}