/*
 * This file is part of Popcorn.
 * Copyright (C) 2007 Mike Smith.
 *
 * 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 2 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, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <lib/types.hpp>
#include <lib/String.hpp>
#include <VConsole.hpp>
#include <Keyboard.hpp>
#include <Timer.hpp>
#include <Panic.hpp>
#include <lib/Assert.hpp>
#include <lib/Alloc.hpp>
#include <Tasks.hpp>
#include <DebugConsole.hpp>
#include <lib/LinkedList.hpp>
#include <Power.hpp>

namespace KShell
{
	typedef struct
	{
		const char *name;
		const char *text;
	} help_t;
	
	help_t help[] =
	{
		{ "help",		"Show this help menu" },
		{ "echo <text>",	"Print text to the screen" },
		{ "halt",		"Halt the CPU" },
		{ "reboot",		"Restart your computer" },
		{ "uptime",		"Show how long Popcorn has been running" },
		{ "syscall",	"Test system calls (should print 'A' to screen)" },
		{ "crash",		"Crash the computer in a way of your choice" },
		{ "kitty",		"Show the obligatory ASCII Art Kitty" },
		{ "tasks",		"List currently running tasks" },
		{ "exit",		"Exit KShell" }
	};

	char cmdbuf[1024];

	void getcmd()
	{
		String::memset(cmdbuf, 0, 1024);
		
		int i = 0;
		while (i < 1024)
		{
			uint_16 key = cout.getchar();
			
			if (key & 0xF000)
			{
				cdebug << "[kshell] non-printing key pressed\n";
			}
			else if (key == '\b')
			{
				if (i)
				{
					cmdbuf[--i] = 0;
					cout << '\b';
				}
			}
			else if (key == '\n')
			{
				cout << "\n";
				return;
			}
			else if (Keyboard::is_ctrl_on() && key == 'c')
			{
				// ^C pressed, clear buffer and return
				String::memset(cmdbuf, 0, 1024);
				cout << "\n";
				return;
			}
			else if (Keyboard::is_ctrl_on() && key == 'l')
			{
				// ^L: Clear screen
				String::memset(cmdbuf, 0, 1024);
				cout.clear();
				return;
			}
			else
			{
				cout << (char)key;
				cmdbuf[i++] = (char)key;
			}
		}
	}

	void prompt()
	{
		cout.set_fg(WHITE);
		cout << ">";
		cout.set_fg(GRAY);
		cout << ">";
		cout.set_fg(DARKGRAY);
		cout << "> ";
		cout.set_fg(GRAY);
	}

	int main(int argc, char *argv[])
	{
		cout << "Welcome to KShell! Type 'help' and press enter for avaliable commands.\n";
		while (1)
		{
			prompt();
			getcmd();
			if (String::strlen(cmdbuf) != 0)
			{
				char *tokptr;
				char *cmd = String::strtok_r(cmdbuf, " ", &tokptr);
				
				if (String::strcmp(cmd, "help") == 0 || String::strcmp(cmd, "?") == 0)
				{
					int num = sizeof(help) / sizeof(help[0]);
					
					for (int i = 0; i < num; i++)
					{
						cout.set_fg(LIGHTCYAN);
						cout << help[i].name;
						cout.set_fg(CYAN);
						cout << ": ";
						cout.set_fg(GRAY);
						cout << help[i].text << "\n";
					}
				}
				else if (String::strcmp(cmd, "echo") == 0)
				{
					char *tok;
					while ((tok = String::strtok_r(NULL, " ", &tokptr)))
						cout << tok << " ";
					cout << "\n";
				}
				else if (String::strcmp(cmd, "halt") == 0)
				{
					Power::halt();
				}
				else if (String::strcmp(cmd, "reboot") == 0)
				{
					Power::reboot();
				}
				else if (String::strcmp(cmd, "uptime") == 0)
				{
					cout.flags(dec);
					cout << "Current Uptime: " << Timer::getuptime() / 1000 << " seconds\n";
				}
				else if (String::strcmp(cmd, "syscall") == 0)
				{
					asm volatile
					(
						"mov $0, %%eax;"
						"mov $0x41, %%ebx;"
						"int $0x7B;"
					:::	"%eax", "%ebx"
					);
				}
				else if (String::strcmp(cmd, "vcprint") == 0)
				{
					cout.print("This is a test\n");
					cout.print("%%d: %d %%x: %x %%b: %b %%c: %c %%s: %s\n", 123, 123, 123, 'a', "asdf");
					cout.print("%%08x: %08x\n", 123);
				}
				else if (String::strcmp(cmd, "crash") == 0)
				{
					cout << "  0. Cancel\n";
					cout << "  1. Write to unmapped memory\n";
					cout << "  2. Divide by 0\n";
					cout << "  3. Execute a UD2 instruction\n";
					cout << "  4. Assert false\n";
					cout << "  5. Trigger a Burnt Popcorn\n";
					cout << "  6. Print a null pointer to cout\n";

					cout << "Please enter your choice: ";
					char c = cout.getchar();
					cout << c << "\n";
					int zero = 0;
					int choice = c - '0';
					switch (choice)
					{
					case 0:
						break;
					case 1:
						*(char *)(0xFFFFFFFF) = 'a';
						break;
					case 2:
						cout << 10 / zero;
						break;
					case 3:
						asm volatile ("ud2");
						break;
					case 4:
						assert(false);
						break;
					case 5:
						panic("foo");
						break;
					case 6:
						cout << (char *)0 << "\n";
						break;
					default:
						cout << "Invalid choice\n";
						break;
					}
				}
				else if (String::strcmp(cmd, "kitty") == 0)
				{
					cout << "             _______ \n";
					cout << "            (_Meow!_)\n";
					cout << "              | /    \n";
					cout << "          /|_ |/     \n";
					cout << "        ,'  .\\     \n";
					cout << "    ,--'    _,'     \n";
					cout << "   /       /        \n";
					cout << "  (   -.  |         \n";
					cout << "  |     ) |         \n";
					cout << " (`-.  `--.)        \n";
					cout << "  `._)----'         \n\n";
				}
				else if (String::strcmp(cmd, "tasks") == 0)
				{
					//Tasks::list_tasks();
				}
				else if (String::strcmp(cmd, "exit") == 0)
				{
					//Tasks::process_end(1);
					while (1);
				}
				else
				{
					cout << "Unknown command " << cmd << "\n";
				}
			}
		}
	}
}