from kandinsky import draw_string, fill_rect
from ion import keydown, KEY_OK, KEY_UP, KEY_DOWN

def display_zone(digits, scroll_y):
    # On garde les 2 premieres lignes intactes (Titre + Compteur)
    fill_rect(0, 50, 320, 172, (255, 255, 255))
    curr_x, curr_y = 10, 50 - scroll_y
    for d in digits:
        if curr_y >= 50 and curr_y <= 200:
            draw_string(d, curr_x, curr_y, (0, 0, 0))
        curr_x += 10
        if curr_x > 300:
            curr_x = 10
            curr_y += 18

def pi_calc():
    # Setup
    fill_rect(0, 0, 320, 222, (255, 255, 255))
    draw_string("PI CALCULATOR", 100, 5, (0, 0, 255))
    
    digits = []
    # Parametres Spigot pour un bloc
    n = 1000 # On calcule par blocs de 1000 pour la stabilite
    len_a = int(10 * n / 3) + 1
    a = [2] * len_a
    
    x, y = 10, 50
    scroll_offset = 0
    
    for j in range(n):
        q = 0
        for i in range(len_a - 1, -1, -1):
            x_val = 10 * a[i] + q * (i + 1)
            a[i] = x_val % (2 * i + 1)
            q = x_val // (2 * i + 1)
        
        a[0] = q % 10
        val = q // 10
        
        # Formatage du chiffre
        char = str(val)
        if len(digits) == 1: digits[0] = digits[0] + "."
        digits.append(char)
        
        # Affichage direct
        draw_string("Decimales: " + str(len(digits)-1), 10, 25, (255, 0, 0))
        
        # On affiche le "3." correctement au debut
        to_print = char
        if len(digits) == 1: to_print = char + "."
        
        draw_string(to_print, x, y - scroll_offset, (0,0,0))
        
        # Avancement curseur
        x += 10
        if x > 300:
            x = 10
            y += 18
            if y - scroll_offset > 200:
                scroll_offset += 18
                display_zone(digits, scroll_offset)
        
        # Pause / Navigation
        if keydown(KEY_OK):
            draw_string("PAUSE", 135, 205, (255, 0, 0))
            while keydown(KEY_OK): pass
            paused = True
            while paused:
                if keydown(KEY_UP) and scroll_offset >= 18:
                    scroll_offset -= 18
                    display_zone(digits, scroll_offset)
                    while keydown(KEY_UP): pass
                if keydown(KEY_DOWN):
                    scroll_offset += 18
                    display_zone(digits, scroll_offset)
                    while keydown(KEY_DOWN): pass
                if keydown(KEY_OK):
                    paused = False
                    fill_rect(0, 205, 320, 18, (255, 255, 255))
                    display_zone(digits, scroll_offset)
                    while keydown(KEY_OK): pass

    draw_string("FIN DU BLOC", 110, 205, (0, 150, 0))

# Lancement
pi_calc()