/*
 *  neercs        console-based window manager
 *  Copyright (c) 2006 Sam Hocevar <sam@zoy.org>
 *                2008 Jean-Yves Lamoureux <jylam@lnxscene.org>
 *                2008 Pascal Terjan <pterjan@linuxfr.org>
 *                All Rights Reserved
 *
 *  $Id$
 *
 *  This program is free software. It comes without any warranty, to
 *  the extent permitted by applicable law. You can redistribute it
 *  and/or modify it under the terms of the Do What The Fuck You Want
 *  To Public License, Version 2, as published by Sam Hocevar. See
 *  http://sam.zoy.org/wtfpl/COPYING for more details.
 */

#include "config.h"

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <time.h>
#include <pwd.h>

#include <errno.h>
#include <caca.h>

#include "neercs.h"

static int send_to_client(const char * msg, struct screen_list* screen_list)
{
    int ret;
    if(!screen_list->socket[SOCK_CLIENT])
        connect_socket(screen_list, SOCK_CLIENT);
    debug("Sending message (%s) to client on socket %d", msg, screen_list->socket[SOCK_CLIENT]);
    if(!screen_list->socket[SOCK_CLIENT])
        ret = -1;
    else
        ret = write(screen_list->socket[SOCK_CLIENT], msg, strlen(msg));
    if(ret < 0 && errno != EAGAIN)
    {
        fprintf(stderr, "Failed to send message to client: %s\n", strerror(errno));
        detach(screen_list);
    }
    return ret;
}

static int set_title(const char * title, struct screen_list* screen_list)
{
    char buf[1024];
    int bytes;

    bytes = snprintf(buf, sizeof(buf)-1, "TITLE %s", title);
    buf[bytes] = '\0';
    return send_to_client(buf, screen_list);
}

static int set_cursor(int state, struct screen_list* screen_list)
{
    char buf[16];
    int bytes;

    bytes = snprintf(buf, sizeof(buf)-1, "CURSOR %d", state);
    buf[bytes] = '\0';

    return send_to_client(buf, screen_list);
}

static int request_refresh(struct screen_list* screen_list)
{
    size_t bytes;
    void *buf;
    char *buf2;
    buf = cucul_export_memory (screen_list->cv, "caca", &bytes);
    buf2 = malloc(bytes+8);
    memcpy(buf2, "REFRESH ", 8);
    memcpy(buf2+8, buf, bytes);
    if(!screen_list->socket[SOCK_CLIENT])
        connect_socket(screen_list, SOCK_CLIENT);
    if(screen_list->socket[SOCK_CLIENT])
        if(write(screen_list->socket[SOCK_CLIENT], buf2, bytes+8) <= 0 && errno != EAGAIN)
        {
            return -1;
        }
    free(buf);
    free(buf2);
    return 0;
}

int detach(struct screen_list* screen_list)
{
    screen_list->attached = 0;
    if(screen_list->socket[SOCK_CLIENT])
    {
        send_to_client("DETACH", screen_list);
        close(screen_list->socket[SOCK_CLIENT]);
        screen_list->socket[SOCK_CLIENT] = 0;
    }
    return 0;
}

static int server_main(int *to_grab, char **to_start, struct screen_list *screen_list)
{
    int i;
    int eof = 0, refresh = 1, command = 0;
    long long unsigned int last_key_time = 0;
    int mainret = 0;

    screen_list->attached = 0;

    /* Create socket and bind it */
    create_socket(screen_list, SOCK_SERVER);

    /* Connect to the client */
    connect_socket(screen_list, SOCK_CLIENT);

    screen_list->width = screen_list->height = 10;

    /* Create main canvas */
    screen_list->cv = cucul_create_canvas(screen_list->width,
                                          screen_list->height
                                          + screen_list->mini*6
                                          + screen_list->status);

    if(!to_grab && !to_start)
    {
        add_screen(screen_list,
                   create_screen(screen_list->width,
                                 screen_list->height,
                                 screen_list->default_shell));
    }

    /* Attach processes */
    if(to_grab)
    {
        for(i=0; to_grab[i]; i++)
        {
            add_screen(screen_list,
                       create_screen_grab(screen_list->width,
                                          screen_list->height,
                                          to_grab[i]));
        }
        free(to_grab);
    }

    /* Launch command line processes */
    if(to_start)
    {
        for(i=0; to_start[i]; i++)
        {
            add_screen(screen_list,
                       create_screen(screen_list->width,
                                     screen_list->height,
                                     to_start[i]));
        }
        free(to_start);
    }

    last_key_time = get_us();

    for(;;)
    {
        int quit = 0;
        ssize_t n;
        char buf[4097];

        /* Read program output */
        refresh |= update_screens_contents(screen_list);

        /* Check if we got something from the client */
        while (screen_list->socket[SOCK_SERVER] && (n = read(screen_list->socket[SOCK_SERVER], buf, sizeof(buf)-1)) > 0)
        {
            buf[n] = 0;
            debug("Received command %s", buf);
            if(!strncmp("ATTACH ", buf, 7))
            {
                screen_list->attached = 1;
                cucul_free_canvas(screen_list->cv);
                screen_list->cv = cucul_create_canvas(atoi(buf+7), atoi(buf+18));
                screen_list->width  = cucul_get_canvas_width(screen_list->cv);
                screen_list->height = cucul_get_canvas_height(screen_list->cv) - ((screen_list->mini*6) + (screen_list->status));
                update_windows_props(screen_list);
                cucul_clear_canvas(screen_list->cv);
                refresh = 1;
            }
            else if(!strncmp("QUIT", buf, 4))
            {
                quit = 1;
            }
            else if(!strncmp("RESIZE ", buf, 7))
            {
                cucul_free_canvas(screen_list->cv);
                screen_list->cv = cucul_create_canvas(atoi(buf+7), atoi(buf+18));
                screen_list->width  = cucul_get_canvas_width(screen_list->cv);
                screen_list->height = cucul_get_canvas_height(screen_list->cv) - ((screen_list->mini*6) + (screen_list->status));
                update_windows_props(screen_list);
                cucul_clear_canvas(screen_list->cv);
                refresh = 1;
            }
            else if(!strncmp("KEY ", buf, 4))
            {
                unsigned int c = atoi(buf+4);
                char *str = NULL;
                int size = 0;
                /* CTRL-A has been pressed before, handle this as a
                 * command, except that CTRL-A a sends literal CTRL-A */
                if(command && (c != 'a'))
                {
                    command = 0;
                    refresh |= handle_command_input(screen_list, c);
                }
                else
                {
                    /* Not in command mode */
                    last_key_time = get_us();
                    set_cursor(1, screen_list);

                    /* Kill screensaver */
                    if(screen_list->in_screensaver)
                    {
                        screensaver_kill(screen_list);
                        screen_list->in_screensaver = 0;
                        refresh = 1;
                        continue;
                    }
                    /* Handle lock window */
                    if(screen_list->locked)
                        refresh |= update_lock(c, screen_list);
                    else
                    {
                        switch(c)
                        {
                        case 0x01: //CACA_KEY_CTRL_A:
                            command = 1; break;
                        case CACA_KEY_ESCAPE:
                            if(screen_list->help)
                            {
                                screen_list->help = 0;
                                refresh = 1;
                                break;
                            }
                        default:
                            /* CTRL-A a sends literal CTRL-A */
                            if (command && (c == 'a'))
                            {
                                c = 0x01;
                            }
                            /* Normal key, convert it if needed */
                            str = convert_input_ansi(&c, &size);
                            write(screen_list->screen[screen_list->pty]->fd, str, size);
                            break;
                        }
                    }
                }
            }
            else
            {
                fprintf(stderr, "Unknown command received: %s\n", buf);
            }
        }

        /* No more screens, exit */
        if(!screen_list->count) break;

        /* User requested to exit */
        if(quit) break;

        /* Update each screen canvas  */
        refresh |= update_terms(screen_list);

        /* Launch reccurents if any */
        refresh |= handle_recurrents(screen_list);

        /* Resfresh screen */
        if(!screen_list->attached)
        {
            /* No need to refresh
             * Don't use the CPU too much
             * Would be better to select on terms + socket
             */
            sleep(1);
        }
        /* Draw lock window */
        else if(screen_list->locked)
        {
            draw_lock(screen_list);
            refresh = 1;
        }
        else
        {
            if((refresh || screen_list->in_bell) &&
               (get_us() - last_key_time < screen_list->screensaver_timeout))
            {
                refresh_screens(screen_list);
                if(screen_list->attached)
                {
                    if(screen_list->pty < screen_list->count &&
                       screen_list->screen[screen_list->pty]->title)
                        set_title(screen_list->screen[screen_list->pty]->title, screen_list);
                    else
                        set_title(PACKAGE_STRING, screen_list);
                }
                refresh = 1;

            }
            if((get_us() - last_key_time > screen_list->screensaver_timeout))
            {
                if(!screen_list->in_screensaver)
                {
                    screensaver_init(screen_list);
                    screen_list->in_screensaver = 1;
                    set_cursor(0, screen_list);
                }
                draw_screensaver(screen_list);
                refresh = 1;
            }

            if((get_us() - last_key_time > screen_list->autolock_timeout))
            {
                screen_list->locked = 1;
                refresh = 1;
            }

        }

        if(refresh)
        {
            if(screen_list->attached)
                request_refresh(screen_list);
            refresh = 0;
        }

        eof = 1;
        for(i=0; i < screen_list->count; i++)
            if(screen_list->screen[i]->fd >= 0)
                eof = 0;
        if(eof)
            break;
    }

    detach(screen_list);

    /* Clean up */
    cucul_free_canvas(screen_list->cv);

    for(i = 0; i < screen_list->count; i++)
    {
        destroy_screen(screen_list->screen[i]);
    }

    if(screen_list->socket_path[SOCK_SERVER])
    {
        unlink(screen_list->socket_path[SOCK_SERVER]);
        free(screen_list->socket_path[SOCK_SERVER]);
    }

    if(screen_list->socket_path[SOCK_CLIENT])
        free(screen_list->socket_path[SOCK_CLIENT]);

    if(screen_list->socket[SOCK_SERVER])
        close(screen_list->socket[SOCK_SERVER]);

    if(screen_list->socket[SOCK_CLIENT])
        close(screen_list->socket[SOCK_CLIENT]);

    if(screen_list->screen) free(screen_list->screen);

    for(i=0; i<screen_list->recurrent_list->count; i++)
    {
        remove_recurrent(screen_list->recurrent_list, i);
        i = 0;
    }

    if(screen_list->recurrent_list->recurrent) free(screen_list->recurrent_list->recurrent);
    if(screen_list->recurrent_list)            free(screen_list->recurrent_list);

    if(screen_list->session_name)
        free(screen_list->session_name);

    if(screen_list)
        free(screen_list);

    return mainret;
}

int start_server(int *to_grab, char **to_start, struct screen_list *screen_list)
{
    pid_t pid;
    char * sess;

    pid = fork();
    if(pid < 0)
    {
        fprintf(stderr, "Failed to create child process\n");
        return 1;
    }
    if(pid == 0)
    {
        int fd;
        close(0);
        close(1);
        close(2);
        fd = open("/dev/null", O_RDWR|O_CREAT, S_IRUSR|S_IWUSR);
        dup2(fd, 0);
#ifndef DEBUG
        dup2(fd, 1);
        dup2(fd, 2);
        if (fd > 2)
            close(fd);
#else
        if(fd != 0)
            close(fd);
        fd = open("/tmp/log.txt", O_RDWR|O_CREAT, S_IRUSR|S_IWUSR);
        dup2(fd, 1);
        dup2(fd, 2);
        if (fd > 2)
            close(fd);
#endif
        setsid();
        return server_main(to_grab, to_start, screen_list);
    }
    create_socket(screen_list, SOCK_CLIENT);
    while((sess = connect_socket(screen_list, SOCK_SERVER)) == NULL)
        usleep(100);
    free(sess);

    /* Create main canvas and associated caca window */
    screen_list->cv = cucul_create_canvas(0, 0);
    screen_list->dp = caca_create_display(screen_list->cv);
    if(!screen_list->dp)
        return 1;
    caca_set_cursor(screen_list->dp, 1);

    request_attach(screen_list);

    return 0;
}

long long get_us(void)
{
    struct timeval tv;
    gettimeofday(&tv, NULL);
    return (tv.tv_sec*(1000000) + tv.tv_usec);
}