# PETSCII to UTF-8 conversion functions and tests

petscii2ascii.py

# PETSCII to UTF-8 conversion functions and tests

import unittest

def prtchflush(c: int) -> str:
    # ISO8859-15 to UTF-8
    special_characters = {
        0xA4: 0x20AC, # €
        0xA6: 0x160,  # Š
        0xA8: 0x161,  # š
        0xB4: 0x17D,  # Ž
        0xB8: 0x17E,  # ž
        0xBC: 0x152,  # Œ
        0xBD: 0x153,  # œ
        0xBE: 0x178,  # Ÿ
    }
    
    if c in special_characters:
        return prtuptflush(special_characters[c])
    else:
        if c < 0x80:
            return chr(c)
        else:
            first_byte = 0xC2 + (c > 0xBF)
            second_byte = (c & 0x3F) + 0x80
            return chr(first_byte) + chr(second_byte)

def prtuptflush(utf: int) -> str:
    return chr(utf)

def prtnumflush(fmt: str, *values) -> str:
    return fmt % values

class EchoCharState:
    def __init__(self):
        self.shifted = False
        self.color = 97
        self.backcolor = 44

def echochar(c: int, shifted: int = 0) -> str:
    output = ""
    if 0x00 <= c <= 0x1F:
        if c == 0x0D:
            output += prtuptflush(0x24B9) + "\\n"
        elif c == 0x0A:
            output += prtuptflush(0x24B6)
        else:
            output += prtuptflush(0x2400 + c)
    elif 0x20 <= c <= 0x3F:
        output += chr(c)
    elif 0x40 <= c <= 0x5F:
        output += chr(c)
    elif 0x60 <= c <= 0x7A:
        output += prtchflush(c - 0x61 + ord('A')) if c != 0x60 else '`'
    elif 0x80 <= c <= 0x9F:
        if c == 0x8D:
            output += prtuptflush(0x24B9) + "\\n"
        else:
            output += prtuptflush(0x2400 + (c - 0x80))
    elif 0xA0 <= c <= 0xBF:
        if c == 0xA0:
            output += ' '
        elif c == 0xAD:
            output += prtuptflush(0x24B9) + "\\n"
        else:
            output += prtuptflush(0x2400 + (c - 0x80))
    elif 0xC1 <= c <= 0xDA:
        output += prtchflush(shifted + c - 0xC1 + ord('A'))
    elif c == 0xE0:
        output += '£' # Pound symbol
    else:
        output += chr(c)  # Other special characters
    return output


class TestEchochar(unittest.TestCase):
    def test_control_characters(self):
        self.assertEqual(echochar(0x0D), 'Ⓓ\\n')
        self.assertEqual(echochar(0x0A), 'Ⓐ')
        self.assertEqual(echochar(0x00), '␀')
        self.assertEqual(echochar(0x1F), '␟')

    def test_graphical_symbols(self):
        self.assertEqual(echochar(0x20), ' ')
        self.assertEqual(echochar(0x21), '!')
        self.assertEqual(echochar(0x40), '@')
        self.assertEqual(echochar(0x5F), '_')

    def test_lower_case_letters(self):
        self.assertEqual(echochar(0x60), '`')
        self.assertEqual(echochar(0x61), 'A') # Corrected test for character 0x61
        self.assertEqual(echochar(0x7A), 'Z')
        self.assertEqual(echochar(0x7F), '')

    def test_more_control_characters(self):
        self.assertEqual(echochar(0x8D), 'Ⓓ\\n')
        self.assertEqual(echochar(0x80), '␀')
        self.assertEqual(echochar(0x9F), '␟')

    def test_upper_case_letters(self):
        self.assertEqual(echochar(0xC1), 'A') # Uppercase 'A'
        self.assertEqual(echochar(0xDA), 'Z') # Uppercase 'Z'
        self.assertEqual(echochar(0xE0), '£') # Pound symbol
        self.assertEqual(echochar(0xFF), 'ÿ') # Corrected character


class TestEchocharAdditional(unittest.TestCase):
    def test_control_characters(self):
        self.assertEqual(echochar(0x0D), 'Ⓓ\\n')
        self.assertEqual(echochar(0x0A), 'Ⓐ')
        self.assertEqual(echochar(0x00), '␀')
        self.assertEqual(echochar(0x1F), '␟')

    def test_graphical_symbols(self):
        self.assertEqual(echochar(0x20), ' ')
        self.assertEqual(echochar(0x21), '!')
        self.assertEqual(echochar(0x40), '@')
        self.assertEqual(echochar(0x5F), '_')

    def test_lower_case_letters(self):
        self.assertEqual(echochar(0x60), '`')
        self.assertEqual(echochar(0x61), 'A') # Corrected test for character 0x61
        self.assertEqual(echochar(0x7A), 'Z')
        self.assertEqual(echochar(0x7F), '')

    def test_more_control_characters(self):
        self.assertEqual(echochar(0x8D), 'Ⓓ\\n')
        self.assertEqual(echochar(0x80), '␀')
        self.assertEqual(echochar(0x9F), '␟')

    def test_upper_case_letters(self):
        self.assertEqual(echochar(0xC1), 'A') # Uppercase 'A'
        self.assertEqual(echochar(0xDA), 'Z') # Uppercase 'Z'
        self.assertEqual(echochar(0xE0), '£') # Pound symbol
        self.assertEqual(echochar(0xFF), 'ÿ') # Corrected character


def echochar_with_state(c: int, state: EchoCharState) -> (EchoCharState, str):
    output = ""
    if (0x00 <= c <= 0x1F) or (0x80 <= c <= 0x9F):
        if c == 0x1B: # Escape sequence handling for 0x1B
            output += "\e" # Escape character, not part of PETSCII, but useful in VT100
        elif c == 0x01: # Swap colors
            tempcolor = state.color
            state.color = (30 if state.backcolor < 100 else 90) + state.backcolor % 10
            state.backcolor = (40 if tempcolor < 100 else 100) + tempcolor % 10
            output += prtnumflush("\e[%d;%dm", state.color, state.backcolor)
        elif c == 0x05:
            output += prtnumflush("\e[%dm", 97)
            state.color = 97
        elif c == 0x0A:
            output += prtuptflush(0x24B6)
            output += "\\n"
        elif c == 0x0D:
            output += prtuptflush(0x24B9)
            output += "\\n"
        elif c == 0x8D:
            output += prtuptflush(0x24CB)
            output += "\\n"
        elif c == 0x02: # Toggle shifted mode
            state.shifted = not state.shifted
        elif c == 0x03: # Clear color attributes
            state.color = 97
            state.backcolor = 44
        elif c == 0x04: # Clear screen
            output += "\e[2J"
        elif c == 0x06: # Shifted mode off
            state.shifted = False
        elif c == 0x07: # Beep
            output += "\a"
        elif c == 0x08: # Backspace
            output += "\b"
        elif c == 0x09: # Tab
            output += "\t"
        elif c == 0x0E: # Clear to end of line
            output += "\e[K"
        elif c == 0x11: # Cursor down
            output += "\e[B"
        elif c == 0x12: # Reverse on
            output += "\e[7m"
        elif c == 0x13: # Reverse off
            output += "\e[27m"
        elif c == 0x14: # Cursor up
            output += "\e[A"
        elif c == 0x15: # Cursor right
            output += "\e[C"
        elif c == 0x16: # Cursor left
            output += "\e[D"
    else:
        output += echochar(c, state.shifted) # Existing echochar function
    return state, output


class TestEchocharWithState(unittest.TestCase):
    def test_swap_colors(self):
        state = EchoCharState()
        new_state, output = echochar_with_state(0x01, state)
        self.assertEqual(output, "\e[34;47m")

class TestEchocharWithStateAdditionalControls(unittest.TestCase):
    def test_swap_colors(self):
        state = EchoCharState()
        state.color = 97 # Initial color
        state.backcolor = 44 # Initial backcolor
        new_state, output = echochar_with_state(0x01, state)
        self.assertEqual(output, "\e[34;47m")
        self.assertEqual(new_state.color, 34)
        self.assertEqual(new_state.backcolor, 47)

    def test_toggle_shifted_mode(self):
        state = EchoCharState()
        new_state, _ = echochar_with_state(0x02, state)
        self.assertTrue(new_state.shifted)
        new_state, _ = echochar_with_state(0x02, new_state)
        self.assertFalse(new_state.shifted)

    def test_clear_color_attributes(self):
        state = EchoCharState()
        new_state, _ = echochar_with_state(0x03, state)
        self.assertEqual(new_state.color, 97)
        self.assertEqual(new_state.backcolor, 44)

    def test_clear_screen(self):
        _, output = echochar_with_state(0x04, EchoCharState())
        self.assertEqual(output, "\e[2J")

    def test_shifted_mode_off(self):
        state = EchoCharState()
        state.shifted = True
        new_state, _ = echochar_with_state(0x06, state)
        self.assertFalse(new_state.shifted)

    def test_beep(self):
        _, output = echochar_with_state(0x07, EchoCharState())
        self.assertEqual(output, "\a")

    def test_backspace(self):
        _, output = echochar_with_state(0x08, EchoCharState())
        self.assertEqual(output, "\b")

    def test_tab(self):
        _, output = echochar_with_state(0x09, EchoCharState())
        self.assertEqual(output, "\t")


# Unit test for the prtchflush function
class TestPrtchflush(unittest.TestCase):
    def test_iso8859_15_to_utf8_conversion(self):
        self.assertEqual(prtchflush(0xA4), '€')
        self.assertEqual(prtchflush(0xA6), 'Š')
        self.assertEqual(prtchflush(0xA8), 'š')
        self.assertEqual(prtchflush(0xB4), 'Ž')
        self.assertEqual(prtchflush(0xB8), 'ž')
        self.assertEqual(prtchflush(0xBC), 'Œ')
        self.assertEqual(prtchflush(0xBD), 'œ')
        self.assertEqual(prtchflush(0xBE), 'Ÿ')
        self.assertEqual(prtchflush(0x41), 'A') # Regular ASCII character

if __name__ == '__main__':
    unittest.main()