"""Command decoding, PETSCII glyphs, and data-byte rendering (PLAN.md Phase 0)."""

from __future__ import annotations

import pytest

from iecpoc import decode, device
from iecpoc.petscii import CAT_CONTROL, CAT_GRAPHIC, CAT_PRINTABLE, to_glyph


# --- command decoding -------------------------------------------------------
@pytest.mark.parametrize(
    "value, mnemonic, primary, secondary",
    [
        (0x24, decode.LISTEN, 4, None),     # LISTEN 4
        (0x20, decode.LISTEN, 0, None),     # LISTEN 0
        (0x3E, decode.LISTEN, 30, None),    # LISTEN 30 (top of range)
        (0x3F, decode.UNLISTEN, None, None),
        (0x48, decode.TALK, 8, None),       # TALK 8
        (0x5F, decode.UNTALK, None, None),
        (0x60, decode.SECOND, None, 0),     # DATA/reopen SA=0
        (0x6F, decode.SECOND, None, 15),
        (0xE0, decode.CLOSE, None, 0),
        (0xEF, decode.CLOSE, None, 15),
        (0xF0, decode.OPEN, None, 0),
        (0xFF, decode.OPEN, None, 15),
    ],
)
def test_decode_command(value, mnemonic, primary, secondary):
    cmd = decode.decode_command(value)
    assert cmd.value == value
    assert cmd.mnemonic == mnemonic
    assert cmd.primary == primary
    assert cmd.secondary == secondary


def test_targets_address():
    assert decode.decode_command(0x24).targets(4) is True
    assert decode.decode_command(0x24).targets(8) is False
    # UNLISTEN has no primary address, targets nobody specifically
    assert decode.decode_command(0x3F).targets(4) is False


def test_describe():
    assert decode.decode_command(0x24).describe() == "LISTEN 4"
    assert decode.decode_command(0x3F).describe() == "UNLISTEN"
    assert decode.decode_command(0xF0).describe() == "OPEN  SA=0"
    assert decode.decode_command(0xE0).describe() == "CLOSE SA=0"


def test_decode_command_range_check():
    with pytest.raises(ValueError):
        decode.decode_command(0x100)


# --- PETSCII ----------------------------------------------------------------
def test_petscii_letters_and_digits():
    for ch in "HELLO WORLD0123456789":
        g = to_glyph(ord(ch))
        assert g.category == CAT_PRINTABLE
        assert g.text == ch


def test_petscii_commodore_glyphs():
    assert to_glyph(0x5C).text == "£"
    assert to_glyph(0x5E).text == "↑"
    assert to_glyph(0x5F).text == "←"


def test_petscii_control_codes():
    assert to_glyph(0x0D) == to_glyph(0x0D)
    cr = to_glyph(0x0D)
    assert cr.category == CAT_CONTROL
    assert cr.text == "<CR>"
    assert to_glyph(0x12).text == "<RVS-ON>"
    # unknown control code falls back to the hex form
    assert to_glyph(0x07).category == CAT_CONTROL
    assert to_glyph(0x07).text == "<$07>"


def test_petscii_graphics_render_as_dot():
    g = to_glyph(0x70)  # graphics range in the upper-case set
    assert g.category == CAT_GRAPHIC
    assert g.text == "."
    assert not g.printable


def test_petscii_range_check():
    with pytest.raises(ValueError):
        to_glyph(256)


# --- data-byte rendering ----------------------------------------------------
def test_describe_data_printable():
    assert decode.describe_data(0x48) == "$48 'H'"


def test_describe_data_control():
    assert decode.describe_data(0x0D) == "$0D <CR>"


# --- event description ------------------------------------------------------
def test_describe_event_atn_released_addressed():
    rec = device.IecRecord(device.KIND_EVENT, device.EV_ATN_RELEASED,
                           device.FLAG_ADDRESSED, 0)
    assert decode.describe_event(rec) == "released -> LISTENER"


def test_describe_event_atn_released_not_addressed():
    rec = device.IecRecord(device.KIND_EVENT, device.EV_ATN_RELEASED, 0, 0)
    assert decode.describe_event(rec) == "released -> not addressed -> IDLE"


def test_describe_event_idle():
    rec = device.IecRecord(device.KIND_EVENT, device.EV_IDLE, 0, 0)
    assert decode.describe_event(rec) == "waiting for ATN"