keyboard.py

"""
On-screen virtual keyboard for touch input.
"""
import pygame


# Colors
BG = (20, 20, 25)
KEY_BG = (50, 50, 60)
KEY_BG_ACTIVE = (80, 80, 100)
KEY_SPECIAL = (35, 35, 50)
KEY_SPECIAL_ACTIVE = (70, 70, 90)
KEY_ENTER = (40, 100, 160)
KEY_ENTER_ACTIVE = (60, 140, 200)
TEXT_COLOR = (230, 230, 235)
BORDER_COLOR = (70, 70, 85)

ROWS_ALPHA = [
    ["q", "w", "e", "r", "t", "y", "u", "i", "o", "p"],
    ["a", "s", "d", "f", "g", "h", "j", "k", "l"],
    ["⇧", "z", "x", "c", "v", "b", "n", "m", "⌫"],
    ["123", " ", ".", "⏎"],
]

ROWS_ALPHA_UPPER = [
    ["Q", "W", "E", "R", "T", "Y", "U", "I", "O", "P"],
    ["A", "S", "D", "F", "G", "H", "J", "K", "L"],
    ["⇧", "Z", "X", "C", "V", "B", "N", "M", "⌫"],
    ["123", " ", ".", "⏎"],
]

ROWS_NUM = [
    ["1", "2", "3", "4", "5", "6", "7", "8", "9", "0"],
    ["-", "/", ":", ";", "(", ")", "=", "&", "@", '"'],
    ["ABC", ".", ",", "?", "!", "'", "#", "+", "⌫"],
    ["ABC", " ", "_", "⏎"],
]


class VirtualKeyboard:
    HEIGHT = 260

    def __init__(self, screen_w, screen_h, font, font_size=20):
        self.screen_w = screen_w
        self.screen_h = screen_h
        self.font = font
        small_size = max(14, font_size - 4)
        self.small_font = pygame.font.SysFont("sans", small_size)
        self.mode = "alpha"  # alpha | alpha_upper | num
        self.active_key = None
        self.y = screen_h - self.HEIGHT
        self._key_rects = []
        self._build_layout()

    def _get_rows(self):
        if self.mode == "alpha_upper":
            return ROWS_ALPHA_UPPER
        elif self.mode == "num":
            return ROWS_NUM
        return ROWS_ALPHA

    def _build_layout(self):
        self._key_rects = []
        rows = self._get_rows()
        pad = 6
        total_h = self.HEIGHT - pad * 2
        row_h = total_h // len(rows)
        key_h = row_h - pad

        for row_i, row in enumerate(rows):
            y = self.y + pad + row_i * row_h + pad // 2
            if row_i < 3:
                # Normal rows — equal width keys
                key_w = (self.screen_w - pad * 2) // len(row) - pad
                total_row_w = len(row) * (key_w + pad) - pad
                x_start = (self.screen_w - total_row_w) // 2
                for col_i, key in enumerate(row):
                    x = x_start + col_i * (key_w + pad)
                    rect = pygame.Rect(x, y, key_w, key_h)
                    self._key_rects.append((key, rect))
            else:
                # Bottom row — custom widths
                avail = self.screen_w - pad * 2
                widths = {}
                for k in row:
                    if k == " ":
                        widths[k] = avail * 40 // 100
                    elif k in ("⏎",):
                        widths[k] = avail * 18 // 100
                    elif k in ("123", "ABC"):
                        widths[k] = avail * 16 // 100
                    else:
                        widths[k] = avail * 8 // 100
                total_w = sum(widths.values()) + pad * (len(row) - 1)
                x = (self.screen_w - total_w) // 2
                for key in row:
                    rect = pygame.Rect(x, y, widths[key], key_h)
                    self._key_rects.append((key, rect))
                    x += widths[key] + pad

    def handle_touch(self, pos):
        """Returns the character to insert, or special action string, or None"""
        for key, rect in self._key_rects:
            if rect.collidepoint(pos):
                self.active_key = key
                return self._process_key(key)
        return None

    def handle_release(self):
        self.active_key = None

    def _process_key(self, key):
        if key == "⌫":
            return "BACKSPACE"
        elif key == "⏎":
            return "ENTER"
        elif key == "⇧":
            self.mode = "alpha_upper" if self.mode == "alpha" else "alpha"
            self._build_layout()
            return "SHIFT"
        elif key == "123":
            self.mode = "num"
            self._build_layout()
            return "MODE"
        elif key == "ABC":
            self.mode = "alpha"
            self._build_layout()
            return "MODE"
        elif key == " ":
            return " "
        else:
            if self.mode == "alpha_upper":
                self.mode = "alpha"
                self._build_layout()
            return key

    def draw(self, surface):
        # Background
        kbd_rect = pygame.Rect(0, self.y, self.screen_w, self.HEIGHT)
        pygame.draw.rect(surface, BG, kbd_rect)
        pygame.draw.line(surface, BORDER_COLOR, (0, self.y), (self.screen_w, self.y), 1)

        for key, rect in self._key_rects:
            is_active = (key == self.active_key)
            if key in ("⏎",):
                bg = KEY_ENTER_ACTIVE if is_active else KEY_ENTER
            elif key in ("⌫", "⇧", "123", "ABC", " "):
                bg = KEY_SPECIAL_ACTIVE if is_active else KEY_SPECIAL
            else:
                bg = KEY_BG_ACTIVE if is_active else KEY_BG

            pygame.draw.rect(surface, bg, rect, border_radius=6)
            pygame.draw.rect(surface, BORDER_COLOR, rect, 1, border_radius=6)

            # Label
            label = key
            if key == " ":
                label = ""
            f = self.small_font if len(label) > 1 else self.font
            txt = f.render(label, True, TEXT_COLOR)
            tx = rect.centerx - txt.get_width() // 2
            ty = rect.centery - txt.get_height() // 2
            surface.blit(txt, (tx, ty))