/* qparser-test - Display the lex, parse, and query tree for a query
 *
 * Copyright © 2011 Austin Clements
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see http://www.gnu.org/licenses/ .
 *
 * Authors: Austin Clements <amdragon@mit.edu>
 */

/* If command-line arguments are given, they are used as the query
 * string.  Otherwise, qparser-test enters "echo mode", in which it
 * accepts queries from stdin.  In echo mode, lines beginning with '['
 * are ignored and lines consisting of whitespace or comments are
 * echoed back to stdout.  All other lines are treated as queries and
 * are echoed back, followed by the results of parsing the query.
 * This allows the output of qparser-test to be fed back in as input.
 *
 * For each, qparser-test displays the lex list of that query, the
 * parse tree of that query, and the generated query tree.  Finally,
 * if the generated query tree differs from that generated by Xapian's
 * query parser, it also displays what Xapian's query parser
 * generated.
 */

#include "../lib/notmuch-private.h"
#include "../lib/database-private.h"

extern "C" {
/* notmuch-client.h also defines INTERNAL_ERROR */
#undef INTERNAL_ERROR
#include "../notmuch-client.h"
}

static notmuch_database_t *notmuch;
static _notmuch_qparser_t *qparser;
static Xapian::QueryParser xqparser;

static char *
query_desc (void *ctx, Xapian::Query q)
{
    char *desc = talloc_strdup (ctx, q.get_description ().c_str ());
    desc += strlen ("Xapian::Query(");
    desc[strlen(desc) - 1] = 0;
    return desc;
}

static void
test_one (void *ctx, const char *query_str)
{
    void *local = talloc_new (ctx);
    Xapian::Query q;
    _notmuch_token_t *toks, *root;
    char *error, *qparser_desc, *xqparser_desc;

    toks = _notmuch_qparser_lex (local, qparser, query_str);
    printf("[lex]    %s\n", _notmuch_token_show_list (local, toks));

    root = _notmuch_qparser_parse (local, qparser, query_str);
    printf("[parse]  %s\n", _notmuch_token_show_tree (local, root));

    root = _notmuch_qparser_transform (qparser, root);
    q = _notmuch_qparser_generate (local, qparser, root, &error);
    if (error)
	printf("[gen]    error %s\n", error);
    else {
	qparser_desc = query_desc (local, q);
	printf("[gen]    %s\n", qparser_desc);
    }

    try {
	unsigned int flags = (Xapian::QueryParser::FLAG_BOOLEAN |
			      Xapian::QueryParser::FLAG_PHRASE |
			      Xapian::QueryParser::FLAG_LOVEHATE |
			      Xapian::QueryParser::FLAG_BOOLEAN_ANY_CASE |
			      Xapian::QueryParser::FLAG_WILDCARD |
			      Xapian::QueryParser::FLAG_PURE_NOT);
	q = xqparser.parse_query (query_str, flags);
	xqparser_desc = query_desc (local, q);
	if (strcmp (qparser_desc, xqparser_desc) != 0)
	    printf("[xapian] %s\n", xqparser_desc);
    } catch (const Xapian::QueryParserError & e) {
	printf("[xapian] error %s\n", e.get_msg ().c_str ());
    }

    talloc_free (local);
}

static _notmuch_qparser_t *
create_qparser (void *ctx)
{
    _notmuch_qparser_t *qparser = _notmuch_qparser_create (ctx, notmuch);
    _notmuch_qparser_add_db_prefix (qparser, "prob", "P", FALSE, FALSE);
    _notmuch_qparser_add_db_prefix (qparser, "lit", "L", TRUE, FALSE);
    _notmuch_qparser_add_db_prefix (qparser, "tag", "K", TRUE, TRUE);
    return qparser;
}

static Xapian::QueryParser
create_xapian_qparser (void)
{
    Xapian::QueryParser xq;
    if (notmuch)
	xq.set_database (*notmuch->xapian_db);
    xq.set_default_op (Xapian::Query::OP_AND);
    xq.add_prefix ("prob", "P");
    xq.add_boolean_prefix ("lit", "L");
    xq.add_boolean_prefix ("tag", "K");
    return xq;
}

int
main (int argc, char **argv)
{
    void *ctx;
    notmuch_config_t *config;

    ctx = talloc_new (NULL);

    if (argc > 1 && strcmp(argv[1], "-d") == 0) {
	argc--;
	argv++;

	/* Open the database */
	config = notmuch_config_open (ctx, NULL, NULL);
	if (config == NULL)
	    return 1;

	notmuch = notmuch_database_open (notmuch_config_get_database_path (config),
					 NOTMUCH_DATABASE_MODE_READ_ONLY);
	if (notmuch == NULL)
	    return 1;
    } else {
	notmuch = NULL;
    }

    qparser = create_qparser (ctx);
    xqparser = create_xapian_qparser ();

    if (argc > 1) {
	char *query_str;
	query_str = query_string_from_args (ctx, argc - 1, argv + 1);
	test_one (ctx, query_str);
    } else {
	/* Echo mode */
	char line[512];
	while (fgets (line, sizeof (line), stdin)) {
	    if (line[0] == '\n' || line[0] == '#') {
		/* Comment or whitespace.  Echo it */
		printf("%s", line);
	    } else if (line[0] == '[') {
		/* Ignore line */
	    } else {
		/* Query */
		if (line[strlen (line) - 1] == '\n')
		    line[strlen (line) - 1] = 0;
		printf("%s\n", line);
		test_one (ctx, line);
	    }
	}
    }

    if (notmuch)
	notmuch_database_close (notmuch);
    return 0;
}