#include <stdio.h>
#include <time.h>
#include <nds.h>
#include "devices/clock.h"
#include "devices/math.h"
#include "devices/screen.h"
#include "bang.h"
#include "core.h"
#include "main_debug.h"

Bedrock br[5] = {};
Bedrock *br_main;
Bedrock *br_sub;
bool main_on_bottom = TRUE;

u8 main_program[] = {
    #include "../include/sysinfo.br.inc"
};
u8 keyboard_program[] = {
    #include "../include/sysinfo.br.inc"
};

// Change to the next screen layout.
void change_layout(void) {
    lcdSwap();
    main_on_bottom = !main_on_bottom;
}

// Scan for input and handle emulator-specific keys.
void receive_input(void) {
    scanKeys();
    if (keysDown() & KEY_SELECT) change_layout();
}


void run_br(Bedrock *br) {
    if (br->awake) {
        switch (evaluate(br, 1000)) {
        case SIG_HALT:   br->alive = FALSE; black_screen(br->scr.nds); br = NULL; return;
        case SIG_SLEEP:  br->awake = FALSE;            return;
        case SIG_DB1:     debug_stacks(br);            return;
        case SIG_DB4:     debug_assert(br);            return;
        default:                                       return;
        }
    }
}

Screen scr_main = {
    .bgv = BG_TILE_RAM(BG_SLOT_VIS),
    .fgv = BG_TILE_RAM(FG_SLOT_VIS),
    .bg  = BG_TILE_RAM(BG_SLOT),
    .fg  = BG_TILE_RAM(FG_SLOT),
    .map = BG_MAP_RAM(MAP_SLOT),
    .pal = BG_PALETTE,
};
Screen scr_sub = {
    .bgv = BG_TILE_RAM_SUB(BG_SLOT_VIS),
    .fgv = BG_TILE_RAM_SUB(FG_SLOT_VIS),
    .bg  = BG_TILE_RAM_SUB(BG_SLOT),
    .fg  = BG_TILE_RAM_SUB(FG_SLOT),
    .map = BG_MAP_RAM_SUB(MAP_SLOT),
    .pal = BG_PALETTE_SUB,
};

int main(void) {
    #define ALIVE(br)  (br && br->alive)
    #define AWAKE(br)  (br && br->alive &&  br->awake)
    #define ASLEEP(br) (br && br->alive && !br->awake)

    init_screens();
    init_clock();
    lcdMainOnBottom();

    // TODO: Remove
    // consoleDemoInit();

    // Load program
    start_br(&br[0], main_program, sizeof(main_program));
    start_br(&br[1], keyboard_program, sizeof(keyboard_program));
    br_main = &br[0];
    br_sub = &br[1];
    br_main->scr.nds = &scr_main;
    br_sub->scr.nds = &scr_sub;

    while (1) {
        if (AWAKE(br_main)) run_br(br_main);
        if (AWAKE(br_sub))  run_br(br_sub);

        bool main_flip = ASLEEP(br_main) && br_main->scr.dirty;
        bool sub_flip = ASLEEP(br_sub) && br_sub->scr.dirty;
        if (main_flip || sub_flip) swiWaitForVBlank();
        if (main_flip) { flip_buffer(br_main->scr.nds); br_main->scr.dirty = false; }
        if (sub_flip) { flip_buffer(br_sub->scr.nds); br_sub->scr.dirty = false; }

        rouse:
        receive_input();
        if (ALIVE(br_main)) {
            inp_read_navigation(&br_main->inp);
            inp_read_gamepad(&br_main->inp);
            if (main_on_bottom)  inp_read_touch(&br_main->inp);
        }
        if (ALIVE(br_sub)) {
            inp_read_navigation(&br_sub->inp);
            inp_read_gamepad(&br_sub->inp);
            if (!main_on_bottom) inp_read_touch(&br_sub->inp);
        }
        if (ASLEEP(br_main)) rouse_br(br_main);
        if (ASLEEP(br_sub))  rouse_br(br_sub);
        if (ASLEEP(br_main) && ASLEEP(br_sub)) {
            // Sleep until next keypad event or clock tick.
            swiIntrWait(1, IRQ_KEYS | IRQ_TIMER0);
            goto rouse;
        }

        if (!br_main && !br_sub) return 0;
    }
}