/*
 * Copyright (c) 2009 Apple Computer, Inc.  All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <curses.h>
#include "preferences.h"
#include "userinput_help.h"
#include "top.h"

static struct {
    int yoffset;
    WINDOW *window;
    PANEL *panel;
    WINDOW *state;
    WINDOW *command;
    WINDOW *description;
} help = {
    .yoffset = 0,
    .window = NULL,
    .panel = NULL,
    .state = NULL,
    .command = NULL,
    .description = NULL
};

static void help_completion(void *tinst, struct user_input_state *s) {
    user_input_set_state(NULL);
}

static void help_draw_text_line(const char *statestr, const char *cmdstr, 
				const char *dstr) {
    mvwaddstr(help.state, help.yoffset, 0, statestr);
    mvwaddstr(help.command, help.yoffset, 0, cmdstr);
    mvwaddstr(help.description, help.yoffset, 0, dstr);

    help.yoffset += 1;
}

static void help_draw_text(void) {
    char buf[32];
    const char *user;

    wattron(help.state, A_UNDERLINE);
    mvwaddstr(help.state, 0, 0, "State");
    wattroff(help.state, A_UNDERLINE);

    wattron(help.command, A_UNDERLINE);
    mvwaddstr(help.command, 0, 0, "Command");
    wattroff(help.command, A_UNDERLINE);

    wattron(help.description, A_UNDERLINE);
    mvwaddstr(help.description, 0, 0, "Description");
    wattroff(help.description, A_UNDERLINE);
  
    help.yoffset += 1;
    
    help_draw_text_line("", "?", "Display this help screen.");
    help_draw_text_line(top_prefs_get_mode_string(), "c<mode>", "Set event counting mode to {a|d|e|n}.");
    help_draw_text_line(top_prefs_get_sort_string(), "o<key>", "Set primary sort key to <key>: [+-]keyname.");
    help_draw_text_line("", "", "Keyname may be:{pid|command|cpu|csw|time|threads|");
    help_draw_text_line("", "", "ports|mregion|rprvt|rshrd|rsize|vsize|vprvt|pgrp|");
    help_draw_text_line("", "", "ppid|state|uid|wq|faults|cow|user|msgsent|msgrecv|");
    help_draw_text_line("", "", "sysbsd|sysmach|pageins}.");
    help_draw_text_line(top_prefs_get_secondary_sort_string(), "O<skey>", "Set secondary sort key to <skey> (see o<key>).");
    help_draw_text_line("", "q", "Quit top.");
    help_draw_text_line("", "S<sig>\\n<pid>", "Send signal <sig> to pid <pid>.");

    if(-1 == snprintf(buf, sizeof(buf), "%d", top_prefs_get_sleep()))
	buf[0] = '\0';
   
    help_draw_text_line(buf, "s<delay>", "Set the delay between updates to <delay> seconds.");
    
    help_draw_text_line(top_prefs_get_mmr() ? "on" : "off",
			"r", "Toggle the memory map reporting.");

    user = top_prefs_get_user();

    help_draw_text_line(user ? user : "", "U<user>", "Only display processes owned by <user>, or all.");

    mvwaddstr(help.window, LINES - 1, 0, "Press any key to continue...");
}

static void help_cleanup(void) {
    if(help.panel) {
	del_panel(help.panel);
	help.panel = NULL;
    }

    if(help.window) {
	delwin(help.window);
	help.window = NULL;
    }

    if(help.state) {
	delwin(help.state);
	help.state = NULL;
    }

    if(help.command) {
	delwin(help.command);
	help.command = NULL;
    }

    if(help.description) {
	delwin(help.description);
	help.description = NULL;
    }
}

static void help_draw(void *tinst, struct user_input_state *s, WINDOW *win,
		       int row, int column) {
    int c;

    do {
	help.yoffset = 0;
	help.window = newwin(LINES, COLS, 0, 0);
	
	if(NULL == help.window) {
	    user_input_set_state(NULL);
	    return;
	}
	
	help.panel = new_panel(help.window);
	
	if(NULL == help.panel) {
	    help_cleanup();
	    user_input_set_state(NULL);
	    return;
	}
        
	help.state = derwin(help.window, LINES - 1, 10, /*y*/ 0, /*x*/ 0);
	help.command = derwin(help.window, LINES - 1, 15, /*y*/ 0, 
			      /*x*/ 10);
	help.description = derwin(help.window, LINES - 1, COLS - 25, /*y*/ 0,
				  /*x*/ 25);
    
	if(NULL == help.state || NULL == help.command || NULL == help.description) {
	    help_cleanup();
	    user_input_set_state(NULL);
	    return;
	}
	
	help_draw_text();
	
	/* Wait for a key press. */
	wtimeout(help.window, -1);
	c = wgetch(help.window);

	help_cleanup();
    } while(KEY_RESIZE == c);

    user_input_set_state(NULL);
 }

struct user_input_state top_user_input_help_state = {
    .offset = 0,
    .completion = help_completion,
    .draw = help_draw
};