#include <math.h>
#include <glib.h>
#include <glib-unix.h>
#include <time.h>
#include <unistd.h>
#include <sys/statvfs.h>
#include <locale.h>

#include "window.h"
#include "log.h"
#include "draw.h"
#include "connect.h"
#include "state.h"

#define EVEN(n) ((int)(n) - ((int)(n) % 2 != 0))

static void log_handler(const char *log_domain,
                        GLogLevelFlags level,
                        const char *message,
                        gpointer log_level)
{
    GLogLevelFlags message_level = level & G_LOG_LEVEL_MASK;

    if ((GLogLevelFlags)log_level < message_level)
        return;

    if (message_level <= G_LOG_LEVEL_WARNING)
        g_printerr("%s\n", message);
    else
        g_print("%s\n", message);
}


static gboolean mainloop_quit(gpointer data)
{
    g_main_loop_quit(data);
    return G_SOURCE_CONTINUE;
}

static gboolean disk_update(gpointer data)
{
    Button *btn = data;

    struct statvfs buffer;
    g_assert(statvfs("/", &buffer) == 0);

    const double total = buffer.f_blocks * buffer.f_frsize;
    const double available = buffer.f_bfree * buffer.f_frsize;
    const double used = total - available;

    g_free(btn->text);
    btn->text = g_strdup_printf("  %d%%", (int)round((used / total) * 100.0));

    log_debug("Updated disk percentage");
    state_redraw(btn->action_data);
    return G_SOURCE_CONTINUE;
}

static gboolean date_update(gpointer data)
{
    Button *btn = data;

    g_free(btn->text);
    GDateTime *time = g_date_time_new_now_local();
    char *date = g_date_time_format(time, "%A %d    %H:%M");
    g_assert(date != NULL);
    btn->text = date;

    struct {
        State *state;
        timer_t timer;
    } *date_ctx = btn->action_data;

    log_debug("Updated date and time");
    state_redraw(date_ctx->state);

    struct timespec current;
    clock_gettime(CLOCK_REALTIME, &current);

    struct itimerspec its = { 0 };
    its.it_value.tv_sec = 60 - (current.tv_sec % 60);
    timer_settime(date_ctx->timer, 0, &its, NULL);

    return G_SOURCE_CONTINUE;
}

static void show_action(Button *btn)
{
    log_info("Called action: %s", btn->text);
}

static void quit_action(Button *btn)
{
    log_info("Quit button pressed");
    g_main_loop_quit(btn->action_data);
}

int main(int argc, char **argv)
{
    setlocale(LC_CTYPE, "");
    g_log_set_default_handler(log_handler, (gpointer)G_LOG_LEVEL_DEBUG);

    GMainLoop *mainloop = g_main_loop_new(NULL, FALSE);

    Connection *con = connect_create();

    Window *win = window_create(con);

    int screen_width = con->screen_size->width;
    int screen_height = con->screen_size->height;

    int height = EVEN(round(screen_height * 0.021));
    int x_padding = EVEN(round(screen_width * 0.005));
    int y_padding = EVEN(round(screen_height * 0.004));

    log_debug("Calculated dimensions [height=%d, x_pad=%d, y_pad=%d]", height, x_padding, y_padding);

    Color background_all = { 0.3, 0.3, 0.3, 1 };
    Drawable *draw = draw_create("Hack 13 Bold", height, x_padding, x_padding, y_padding, 0);
    draw_set_background(draw, background_all);

    State *state = state_create(win, draw);

    Color background = { 0.4, 0.4, 0.4, 1 };
    Color foreground = { 0.8, 0.8, 0.8, 1 };
    Color stroke = { 0.8, 0.8, 0.8, 1 };

    for (int i = 0; i < 9; ++i) {
        char text[] = { '1' + i, '\0' };
        Button *btn = button_create(text, PANGO_ALIGN_LEFT);
        button_set_colors(btn, background, foreground, stroke);
        button_set_action(btn, show_action, NULL);
        state_add_button(state, btn);
    }

    Button *disk_btn = button_create("disk", PANGO_ALIGN_RIGHT);
    button_set_colors(disk_btn, background, foreground, stroke);
    button_set_action(disk_btn, show_action, state);
    state_add_button(state, disk_btn);

    disk_update(disk_btn);
    g_timeout_add(60 * 1000, disk_update, disk_btn);

    struct {
        State *state;
        timer_t timer;
    } date_ctx = { state, 0 };

    Button *date_btn = button_create("date", PANGO_ALIGN_CENTER);
    button_set_colors(date_btn, background, foreground, stroke);
    button_set_action(date_btn, show_action, &date_ctx);
    state_add_button(state, date_btn);

    struct sigevent sev = { 0 };
    sev.sigev_notify = SIGEV_SIGNAL;
    sev.sigev_signo = SIGUSR1;

    g_assert(timer_create(CLOCK_REALTIME, &sev, &date_ctx.timer) == 0);
    date_update(date_btn);

    // purple
    Color background2 = { 0.502, 0.168, 0.886, 1 };
    Button *q_btn = button_create("Q", PANGO_ALIGN_RIGHT);
    button_set_colors(q_btn, background2, foreground, stroke);
    button_set_action(q_btn, quit_action, mainloop);
    state_add_button(state, q_btn);

    connect_attach_state(con, state);
    connect_attach_source(con);

    guint source_alrm = g_unix_signal_add(SIGUSR1, date_update, date_btn);
    guint source_term = g_unix_signal_add(SIGTERM, mainloop_quit, mainloop);
    guint source_int  = g_unix_signal_add(SIGINT,  mainloop_quit, mainloop);

    state_redraw(state);

    log_debug("Starting main loop");
    g_main_loop_run(mainloop);

    log_debug("Cleaning main loop");
    g_clear_pointer(&mainloop, g_main_loop_unref);

    g_source_remove(source_alrm);
    g_source_remove(source_term);
    g_source_remove(source_int);

    timer_delete(date_ctx.timer);

    state_destroy(state);
    draw_destroy(draw);
    window_destroy(win);

    return 0;
}

// vim: ts=4 sw=4 et