/*
 *	PROGRAM:	JRD Command Oriented Query Language
 *	MODULE:		help.e
 *	DESCRIPTION:	Help module.
 *
 * The contents of this file are subject to the Interbase Public
 * License Version 1.0 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy
 * of the License at http://www.Inprise.com/IPL.html
 *
 * Software distributed under the License is distributed on an
 * "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express
 * or implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code was created by Inprise Corporation
 * and its predecessors. Portions created by Inprise Corporation are
 * Copyright (C) Inprise Corporation.
 *
 * All Rights Reserved.
 * Contributor(s): ______________________________________.
 *
 * 2002.10.30 Sean Leyne - Removed support for obsolete "PC_PLATFORM" define
 *
 */

#include "firebird.h"
#include "../jrd/ib_stdio.h"
#include <string.h>
#include "../jrd/gds.h"
#include "../qli/dtr.h"
#include "../qli/compile.h"
#include "../qli/err_proto.h"
#include "../qli/help_proto.h"
#include "../qli/lex_proto.h"
#include "../jrd/gds_proto.h"

#define INDENT		"  "
#define COLUMN_WIDTH	20
#define RIGHT_MARGIN	70

#ifdef VMS
#define TARGET	"[syshlp]help.gdb"
#endif

#ifdef UNIX
#define TARGET "help/help.gdb"
#endif

#if (defined WIN_NT)
#define TARGET "help/help.gdb"
#endif

DATABASE HELP_DB = STATIC "help.gdb" RUNTIME target;

static int additional_topics(TEXT *, TEXT *, TEXT *);
static void print_more(USHORT, USHORT, TEXT **, USHORT *, TEXT *, USHORT);
static void print_topic(USHORT, USHORT, TEXT **, USHORT *, TEXT *, USHORT);
static TEXT *strip(TEXT *);


void HELP_fini(void)
{
/**************************************
 *
 *	H E L P _ f i n i
 *
 **************************************
 *
 * Functional description
 *
 **************************************/

	if (HELP_DB) {
		COMMIT;
		FINISH;
	}
}


void HELP_help( SYN node)
{
/**************************************
 *
 *	H E L P _ h e l p
 *
 **************************************
 *
 * Functional description
 *	Give the poor sucker help.
 *
 **************************************/
	NAM *ptr, *end;
	USHORT max_level;
	TEXT target[128], **topic, *topics[16];

	if (!HELP_DB) {
		gds__prefix(target, TARGET);
		READY
		ON_ERROR
			ERRQ_database_error((struct dbb*) NULL_PTR, gds_status);
		END_ERROR;
		START_TRANSACTION;
	}

	max_level = 0;
	topic = topics;
	*topic++ = "QLI";

	for (ptr = (NAM *) node->syn_arg, end = ptr + node->syn_count; ptr < end;
		 ptr++)
		*topic++ = (*ptr)->nam_string;

	print_topic(0, node->syn_count, topics, &max_level, "", FALSE);

	if (max_level < node->syn_count)
		print_topic(0, node->syn_count, topics, &max_level, "", TRUE);
}


static int additional_topics( TEXT * parent, TEXT * banner, TEXT * string)
{
/**************************************
 *
 *	a d d i t i o n a l _ t o p i c s
 *
 **************************************
 *
 * Functional description
 *	Print a list of other known topics.
 *
 **************************************/
	TEXT *p, line[256], *ptr;
	USHORT topics, l;

/* Print list of know topics.  When we find the first, 
   print the banner, if any */

	ptr = line;
	topics = 0;
	l = strlen(parent);

	FOR X IN TOPICS WITH X.PARENT EQ parent SORTED BY X.TOPIC
		if (QLI_abort)
			return 0;
		p = X.TOPIC;
		while (*p && *p != ' ')
			p++;
		if (!(l = p - X.TOPIC))
			continue;
		if (++topics == 1 && banner)
			ib_printf("%s%s%s\n", banner, string, parent);
		p =
			line +
			((ptr - line + COLUMN_WIDTH - 1) / COLUMN_WIDTH) * COLUMN_WIDTH;
		if (p + l > line + RIGHT_MARGIN) {
			*ptr = 0;
			ib_printf("%s%s\n", INDENT, line);
			p = ptr = line;
		}
		while (ptr < p)
			*ptr++ = ' ';
		p = X.TOPIC;
		do
			*ptr++ = *p++;
		while (--l);
		*ptr++ = ' ';
	END_FOR;

	if (ptr != line) {
		*ptr = 0;
		ib_printf("%s%s\n", INDENT, line);
	}

	return topics;
}


static void print_more(
					   USHORT level,
					   USHORT depth,
					   TEXT ** topics,
					   USHORT * max_level, TEXT * parent, USHORT error_flag)
{
/**************************************
 *
 *	p r i n t _ m o r e
 *
 **************************************
 *
 * Functional description
 *	We have printed a topic with additional sub-topics.  Ask the user if he
 *	wants more.
 *
 **************************************/
	TEXT buffer[256], topic[80], prompt[80], *p, *q;

	ERRQ_msg_get(502, prompt);	/* Msg502 "Subtopic? "  */

/* Prompt the user for a line */

	if (!LEX_get_line(prompt, buffer, sizeof(buffer)))
		return;

/* Upcase the response and zap the blanks */

	topics[1] = p = topic;

	for (q = buffer; *q && *q != '\n'; q++)
		if (*q != ' ')
			*p++ = UPPER(*q);
	*p = 0;

/* If we got anything, print the new topic */

	if (p != topic)
		print_topic(level + 1, depth + 1, topics + 1, max_level, parent,
					FALSE);
}


static void print_topic(
						USHORT level,
						USHORT depth,
						TEXT ** topics,
						USHORT * max_level, TEXT * parent, USHORT error_flag)
{
/**************************************
 *
 *	p r i n t _ t o p i c
 *
 **************************************
 *
 * Functional description
 *	Lookup topic in path.  If we find a topic, and are not level
 *	zero, recurse.  Otherwise print out the topic.  In any case,
 *	remember the lowest level on which a topic was found.  If the
 *	error flag is set, print out a list of sub-topics.
 *
 **************************************/
	USHORT count;
	TEXT string[128], banner[128], *next, *p, *q, *path, buffer[128],
		prompt[80];

/* Copy the parent string inserting a blank at the end */

	p = string;

	if (*parent) {
		q = parent;
		while (*q)
			*p++ = *q++;
		*p++ = ' ';
	}

	next = p;
	count = 0;

	FOR X IN TOPICS WITH X.FACILITY EQ "QLI" AND
		(X.TOPIC STARTING WITH * topics AND X.PARENT EQ parent) OR
         (X.TOPIC = X.FACILITY AND X.TOPIC = *topics AND X.TOPIC = X.PARENT)
        count++;
	END_FOR;

	if (count > 1)
		ERRQ_msg_put(80, (TEXT *) (ULONG) count, *topics, NULL, NULL, NULL);	/* Msg80 [%d topics matched %s] */

	count = 0;

	FOR(LEVEL level) X IN TOPICS WITH X.FACILITY EQ "QLI" AND
		(X.TOPIC STARTING WITH * topics AND X.PARENT EQ parent) OR
        (X.TOPIC = X.FACILITY AND X.TOPIC = *topics AND X.TOPIC = X.PARENT)
		SORTED BY X.TOPIC 

        if (QLI_abort)
			  return;

		if (count) {
			ERRQ_msg_get(503, prompt);	/* Msg503 "\ntype <cr> for next topic or <EOF> to stop: " */
			if (!LEX_get_line(prompt, buffer, sizeof(buffer)))
				return;
		}
		++count;
		if (level > *max_level)
			*max_level = level;
		p = next;
		q = X.TOPIC;
		while (*q && *q != ' ')
			*p++ = *q++;
		*p = 0;
		if (level < depth)
			print_topic(level + 1, depth, topics + 1, max_level, string,
						error_flag);
		else {
			ib_printf("\n%s\n\n", strip(string));
			QLI_skip_line = TRUE;
			FOR B IN X.TEXT
				if (QLI_abort)
					return;
				B.SEGMENT[B.LENGTH] = 0;
				ib_printf("%s%s", INDENT, B.SEGMENT);
			END_FOR;
			ERRQ_msg_format(81, sizeof(banner), banner, INDENT, NULL, NULL,
							NULL, NULL);	/* Msg81 %sSub-topics available: */
			if (additional_topics(string, banner, INDENT))
				print_more(level, depth, topics, max_level, string,
						   error_flag);
		}
	END_FOR;

	if (!count && error_flag && level > *max_level) {
		path = strip(parent);
		ERRQ_msg_put(82, path, *topics, NULL, NULL, NULL);	/* Msg82 No help is available for %s %s */
		ERRQ_msg_format(83, sizeof(banner), banner, path, NULL, NULL, NULL, NULL);	/* Msg83 Sub-topics available for %s are: */
		additional_topics(parent, banner, path);
	}
}


static TEXT *strip( TEXT * string)
{
/**************************************
 *
 *	s t r i p
 *
 **************************************
 *
 * Functional description
 *	Strip off the first topic in the path.
 *
 **************************************/
	TEXT *p;

	p = string;

	while (*p != ' ')
		if (!*p++)
			return string;

	while (*p == ' ')
		if (!*p++)
			return string;

	return p;
}