#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <sys/time.h>
#include <pthread.h>
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <termios.h>
#include <unistd.h>
#include <dirent.h>
#include <pwd.h>

#include <SDL2/SDL.h>
#include "display.h"
#include "config.h"
#include "engine.h"
#include "calib.h"
#include "menu.h"

/***
    Global config and status values
 ***/

/* Window width and height */
enum {
    HARFE_WIDTH = 1024,
    HARFE_HEIGHT = 768,
    SCREEN_WIDTH = 800,
    SCREEN_HEIGHT = 600
};

int     g_harfe_connected = 0;
int     g_harfe_fd = -1;

static int g_up_pressed, g_down_pressed, g_mouse_down;
static LPoint g_last_mouse;

static char *
find_harfe()
{
    // Device name should be a cu.device
    // followed by the letter HAR somewhere
    // e.g. /dev /cu.usbmodemHAR1
    DIR * dev = opendir("/dev/");
    struct dirent *dp;
    char *harfe = 0;

    if (!dev)
        return 0;

    while ((dp = readdir(dev)) != NULL) {
        size_t len = dp->d_namlen;
        char *name = dp->d_name;
        int i;

        if (len < 6 || name[0] != 'c' || name[1] != 'u' || name[2] != '.')
            continue;

        for (i = 0; i < len - 3; ++i)
            if (name[i] == 'H' && name[i + 1] == 'A' && name[i + 2] == 'R' ) {
                if ((harfe = calloc(1, 5 + len + 1))) {
                    sprintf(harfe, "/dev/");
                    memcpy(harfe + 5, name, len);
                }
                break;
            }
    }
    closedir(dev);

    return harfe;
}

int
set_interface_attribs(int fd, int speed, int parity)
{
    struct termios tty;

    memset(&tty, 0, sizeof tty);
    if (tcgetattr(fd, &tty) != 0)
        return -1;
    cfsetospeed(&tty, speed);
    cfsetispeed(&tty, speed);

    tty.c_cflag = (tty.c_cflag & ~CSIZE) | CS8;
    tty.c_iflag &= ~IGNBRK;
    tty.c_lflag = 0;
    tty.c_oflag = 0;
    tty.c_cc[VMIN] = 0;
    tty.c_cc[VTIME] = 5;

    tty.c_iflag &= ~(IXON | IXOFF | IXANY);

    tty.c_cflag |= (CLOCAL | CREAD);

    tty.c_cflag &= ~(PARENB | PARODD);
    tty.c_cflag |= parity;
    tty.c_cflag &= ~CSTOPB;
    tty.c_cflag &= ~CRTSCTS;

    if (tcsetattr(fd, TCSANOW, &tty) != 0)
        return -1;
    return 0;
}

void
set_blocking(int fd, int should_block)
{
    struct termios tty;

    memset(&tty, 0, sizeof tty);
    if (tcgetattr(fd, &tty) != 0)
        return;

    tty.c_cc[VMIN] = should_block ? 1 : 0;
    tty.c_cc[VTIME] = 5;

    if (tcsetattr(fd, TCSANOW, &tty) != 0)
        return;
}

uint32_t
now()
{
    struct timeval now;

    gettimeofday(&now, (struct timezone *)NULL);
    return now.tv_sec * 1000 + now.tv_usec / 1000;  /* in ms */
}

static uint32_t g_last_avg;
static uint32_t g_starttime, g_last_mouse_event, g_lastredraw;
static int g_events;
static void
harfe_worker(void)
{
    LPoint p[4];
    char text[256], *lineend;
    int fd, i, text_fill = 0, consumed, running = 1;
    uint32_t ptime;

    char *portname = find_harfe();

    if (!portname) {
        printf("Can't find harfe serial device...");
        return;
    }
    g_harfe_fd = open(portname, O_RDWR | O_NOCTTY | O_SYNC);
    if (g_harfe_fd < 0) {
        free(portname);
        printf("Can't connect to harfe...");
        return;
    }
    set_interface_attribs(g_harfe_fd, B115200, 0);
    set_blocking(g_harfe_fd, 0);

    printf("Connection to harfe established at %s.\n", portname);
    free(portname);
    g_harfe_connected = 1;

    /* Get remote config (if any) */
    config_reset();
    write(g_harfe_fd, "S2\n", 3);
    usleep(50);
    g_importing_config = 1;
    write(g_harfe_fd, "I\n", 2);

    while (running) {
        while (text_fill < sizeof(text) && !memchr(text, '\n', text_fill)) {
            ssize_t b = read(g_harfe_fd, text + text_fill, sizeof(text) - text_fill);

            if ((b < 0) && (errno != EAGAIN)) {
                printf("Connection to harfe lost...");
                running = 0;
                close(g_harfe_fd);
                g_harfe_fd = -1;
                break;
            }
            text_fill += b;
        }

        //Overlong line, drop it and try to resync
        if (text_fill == sizeof(text)) {
            text_fill = 0;
            continue;
        }

        // find and remove newline and cf
        if (!(lineend = memchr(text, '\n', text_fill)))
            continue;

        *lineend = 0;
        if (text_fill && lineend[-1] == '\r')
            lineend[-1] = 0;
        printf( "%s\n", text );

        if (g_importing_config) {
            if (!strcmp(text, "-- DONE")) {
                g_importing_config = 0;
                g_config_source = source_harfe;
            } else
                config_handle_line(text);
        } else {

            int num_points = sscanf(text, "%04d:%04d %04d:%04d %04d:%04d %04d:%04d", &p[0].x, &p[0].y, &p[1].x, &p[1].y, &p[2].x, &p[2].y, &p[3].x, &p[3].y);

            ptime = now();
            for (i = 0; i < num_points / 2; ++i) {
                // printf("%04d:%04d\n", p[i].x, p[i].y);

                if (!g_calibration_running)
                    engine_handle_point(p + i, ptime);
                else
                    calib_handle_point(p + i, ptime);
            }
            if (num_points > 1 || *text == '-')
                ++g_events;
        }

        consumed = lineend - text + 1;
        memmove(text, lineend + 1, text_fill - consumed);
        text_fill -= consumed;
    }
    return;
}

static void *
worker(void *args)
{
    while (1) {
        harfe_worker();
        g_harfe_connected = 0;
        printf(" retrying in 5 seconds.\n");
        sleep(5);
    }
}

static void
config_parse(char *config_file)
{
    FILE *fh = fopen(config_file, "r");
    char line_in[512];

    if (!fh) {
        fprintf(stderr, "Couldn't open config file %s, exiting.\n", config_file);
        exit(1);
    }
    config_reset();
    while (!feof(fh)) {
        char *line = fgets(line_in, sizeof(line_in), fh);

        if (!line)
            continue;
        if (config_handle_line(line))
            exit(1);
    }

    fclose(fh);
    g_config_source = source_file;
}

void config_save() {
    const char *homeDir = getenv("HOME");
    char savefile[512], date[32], confdump[512];
    time_t t = time(NULL);
    struct tm *tmp = localtime(&t);
    int i, fd;
    size_t len;

    if (!homeDir) {
        struct passwd* pwd = getpwuid(getuid());
        if (pwd)
            homeDir = (const char*)pwd->pw_dir;
    }
    strftime(date, sizeof(date), "%Y-%m-%d-%H-%M-%S", tmp);
    snprintf( savefile, sizeof(savefile), "%s/Laserharfe-%s.cfg", homeDir, date);
    fd = open(savefile, O_WRONLY | O_CREAT | O_TRUNC, 0644);

    len = config_dumpglobals( confdump, sizeof(confdump));
    write(fd, confdump, len );
    for (i=0; i<g_string_count; ++i) {
        len = config_dumpstring(i, confdump, sizeof(confdump));
        write(fd, confdump, len );
    }
    close(fd);

    snprintf(savefile, sizeof(savefile), "Config saved to your home directory at %s/Laserharfe-%s.cfg", homeDir, date);
    display_messagebox("Config saved", savefile);
}

void config_import() {
    fprintf( stderr, "import config\n" );
    if (g_harfe_connected) {
        config_reset();
        g_importing_config = 1;
        write(g_harfe_fd, "I\n", 2);
    } else
        display_messagebox( "Not connected", "Can't import config if Harfe is not connected.");
}

void config_export() {
    size_t len;
    char confdump[512];
    int i;
    if (!g_harfe_connected) {
        display_messagebox( "Not connected", "Can't write config if Harfe is not connected.");
        return;
    }
    if ((int)g_config_source < 2) {
        display_messagebox( "No changes", "Config is unchanged. Won't write config to Harfe.");
        return;
    }
    write(g_harfe_fd, "E\n", 2);
    len = config_dumpglobals( confdump, sizeof(confdump));
    write(g_harfe_fd, confdump, len );
    for (i=0; i<g_string_count; ++i) {
        len = config_dumpstring(i, confdump, sizeof(confdump));
        write(g_harfe_fd, confdump, len );
        usleep(1000);
    }
    write(g_harfe_fd, "-- DONE\n", 8); /* End dump marker */
    write(g_harfe_fd, "W\n", 2); /* Remote write to SD */
    g_config_source = source_harfe;
}

void
handle_keydown(SDL_Event *ev) {
    switch (ev->key.keysym.scancode) {
     case SDL_SCANCODE_RETURN:
        menu_setmode(1, 1);
        break;
     case SDL_SCANCODE_ESCAPE:
        if (g_importing_config) {
            g_importing_config = 0;
            config_reset();
        }
        calib_stop();
        menu_setmode(6, 0);
        break;
    case SDL_SCANCODE_UP:
        if (ev->key.repeat || !g_up_pressed++)
            engine_change_selected(1);
        break;
    case SDL_SCANCODE_DOWN:
        if (ev->key.repeat || !g_down_pressed++)
            engine_change_selected(-1);
        break;
    case SDL_SCANCODE_0:
        engine_select_config(sel_none);
        break;
    case SDL_SCANCODE_1:
        engine_select_config(sel_min_y);
        break;
    case SDL_SCANCODE_2:
        engine_select_config(sel_max_y);
        break;
    case SDL_SCANCODE_3:
        engine_select_config(sel_2_oct);
        break;
    case SDL_SCANCODE_4:
        engine_select_config(sel_3_oct_bottom);
        break;
    case SDL_SCANCODE_5:
        engine_select_config(sel_3_oct_top);
        break;
    case SDL_SCANCODE_C:
        if (g_calibration_running) {
            calib_fetch();
            menu_setmode(1<<3, 0);
        } else {
            calib_init();
            menu_setmode(0, 3);
        }
        break;
    case SDL_SCANCODE_E:
        config_export();
        break;
    case SDL_SCANCODE_I:
        config_import();
        break;
    case SDL_SCANCODE_L:
        config_parse("config_midi");
        break;
    case SDL_SCANCODE_M:
        if (g_harfe_connected && (g_harfe_fd != -1)) {
            fprintf( stderr, "MIDIing on %d\n", g_harfe_fd );
            write(g_harfe_fd, "ME20020\nM824C00\n", 16);
        }
        break;
    case SDL_SCANCODE_N:
        engine_toggle_normalize_mode();
        break;
    case SDL_SCANCODE_P:
        config_flip_pitch();
        break;
    case SDL_SCANCODE_Q:
        config_reset();
        break;
    case SDL_SCANCODE_R:
        if (g_calibration_running)
            calib_init();
        break;
    case SDL_SCANCODE_S:
        config_save();
        break;
    case SDL_SCANCODE_W:
        fprintf( stderr, "write remote config\n" );
        write(g_harfe_fd, "W\n", 2);
        break;
    case SDL_SCANCODE_X:
        config_reverse_strings();
        break;
    case SDL_SCANCODE_Y:
        config_flip_y();
        break;
    case SDL_SCANCODE_NONUSBACKSLASH:
        menu_setmode(2,2);
        break;
#ifdef CALIB_DEBUG
    case SDL_SCANCODE_SPACE:
        if (g_calibration_running)
            calib_next(10);
        break;
#endif
    default:
        break;
    } /* endswitch */

    /* Handle the ugly German keyboard <> key mapping */
    if (ev->key.keysym.sym == SDLK_GREATER)
         menu_setmode(2,2);
}

int
main(int argc, char **argv)
{
    SDL_Event ev;
    int i, counter = 0;
    pthread_t thread_id;
    uint32_t runtime;
    static int last_click_x, last_click_y, last_mouse_event;

    display_init(SCREEN_WIDTH, SCREEN_HEIGHT, HARFE_WIDTH, HARFE_HEIGHT);
    engine_init();

    pthread_create(&thread_id, NULL, worker, NULL);

/*
   E - Export config to Harfe (with implicite write to SD)
   I - Import config from Harfe
   W - Write config on Harfe to SD (no implicite Transfer)

   S - Save config to local file
   L - Load config from local default (config_midi)

   Y - Invert String order
   X - Invert Octave order

   Q - Reset local Config
   C - Start calibration
   M - Play MIDI C through Harfe
*/

    /* Spin and let call back do all the work */
    while (1) {
        SDL_WaitEventTimeout(&ev, 10);
        switch (ev.type) {
            case SDL_QUIT:
                exit(0);
            case SDL_KEYUP:
                if (ev.key.keysym.scancode == SDL_SCANCODE_UP) g_up_pressed = 0;
                if (ev.key.keysym.scancode == SDL_SCANCODE_DOWN) g_down_pressed = 0;
                break;
            case SDL_KEYDOWN:
                handle_keydown(&ev);
                break;
            case SDL_MOUSEMOTION:
                if (ev.motion.state & SDL_BUTTON_LMASK) {
                    LPoint p = { display_scale_screen_to_harfe(ev.motion.x), 768 - display_scale_screen_to_harfe(ev.motion.y) };
                    engine_handle_point(&p, now());
                    g_last_mouse = p;
                    engine_mouse_y((65336 * (SCREEN_HEIGHT-ev.motion.y))/ SCREEN_HEIGHT);
                }
                break;
            case SDL_MOUSEBUTTONDOWN:
                {
                    LPoint p = { display_scale_screen_to_harfe(ev.button.x), 768 - display_scale_screen_to_harfe(ev.button.y) };
                    if (menu_test_mouse_down(ev.button.x, ev.button.y))
                        engine_handle_point(&p, now());
                    g_last_mouse = p;
                    g_mouse_down = 1;
                }
                break;
            case SDL_MOUSEBUTTONUP:
                {
                    LPoint p = { display_scale_screen_to_harfe(ev.button.x), 768 - display_scale_screen_to_harfe(ev.button.y) };
                    menu_handle_button_up(ev.button.x, ev.button.y);
                    g_mouse_down = 0;
                }

                break;
            case SDL_DROPFILE:
                {
                    char t[512];
                    int ret;
                    snprintf( t, sizeof(t), "Do you want to import config file %s?\n", ev.drop.file);
                    if ((ret= display_messagebox_yesno("Import Laserharfe config", t)))
                        config_parse(ev.drop.file);
                    printf( "Dropped: %s (%d)\n", ev.drop.file, ret );
                    break;
                }
            default:
                break;
        }

        if (g_mouse_down)
            engine_handle_point(&g_last_mouse, now());

        if (!g_calibration_running || !g_importing_config)
            engine_checksilence(now());

        runtime = now();
        if (runtime - g_lastredraw > 30) {
            g_lastredraw = runtime;

            if (!g_calibration_running)
                engine_redraw();
            else
                calib_redraw();

        }
        if (runtime / 1000 - g_last_avg > 10) {
            if (g_events)
                printf("avg: %i\n", g_events / 10);
            g_events = 0;
            g_last_avg = runtime / 1000;
        }
    }

    return 0;
}