Improve provisoning qr display

Author: jepler

src/ttotp/__main__.py

@@ -6,7 +6,6 @@
 
 from dataclasses import dataclass, field
 
-import io
 import signal
 import time
 import hashlib
@@ -35,6 +34,7 @@
 import qrcode
 
 from .TinyProgress import TinyProgress as ProgressBar
+from .sixel import matrix_to_sixel
 
 from typing import TypeGuard  # use `typing_extensions` for Python 3.9 and below
 
@@ -118,16 +118,18 @@ def do_clear_copy(self) -> bool:
 class Qr(ModalScreen[None]):
     """Displays a QR code in a modal dialog"""
 
+    BINDINGS = [
+        Binding("escape", "dismiss", "Close", show=True),
+    ]
+
     def __init__(self, url: str) -> None:
         self.url = url
         super().__init__(classes="Qr")
 
     def compose(self) -> ComposeResult:
         q = qrcode.QRCode(error_correction=qrcode.ERROR_CORRECT_L)
         q.add_data(self.url)
-        out = io.StringIO()
-        q.print_ascii(out=out)
-        content = out.getvalue()
+        content = matrix_to_sixel(q.get_matrix())
         yield Vertical(Label(content), Button("OK"), id="dialog")
 
     def on_button_pressed(self, event: Button.Pressed) -> None:
@@ -375,7 +377,7 @@ class TTOTP(App[None]):
         border: thick $background 80%;
         background: $surface;
     }
-    #dialog Button { align: center middle; }
+    #dialog Button { width: 100%; }
     """
 
     BINDINGS = [

src/ttotp/sixel.py

@@ -0,0 +1,105 @@
+# SPDX-FileCopyrightText: 2023 Jeff Epler
+#
+# SPDX-License-Identifier: MIT
+from __future__ import annotations
+
+TYPE_CHECKING = False
+if TYPE_CHECKING:
+    from typing import Generator, Sequence
+
+    MatrixType = Sequence[Sequence[bool]]
+    SixelMapType = dict[tuple[int, int, int, int, int, int], str]
+
+_sixels = {
+    (0, 0, 0, 0, 0, 0): " ",  # Exception
+    (1, 0, 0, 0, 0, 0): "\U0001fb00",
+    (0, 1, 0, 0, 0, 0): "\U0001fb01",
+    (1, 1, 0, 0, 0, 0): "\U0001fb02",
+    (0, 0, 1, 0, 0, 0): "\U0001fb03",
+    (1, 0, 1, 0, 0, 0): "\U0001fb04",
+    (0, 1, 1, 0, 0, 0): "\U0001fb05",
+    (1, 1, 1, 0, 0, 0): "\U0001fb06",
+    (0, 0, 0, 1, 0, 0): "\U0001fb07",
+    (1, 0, 0, 1, 0, 0): "\U0001fb08",
+    (0, 1, 0, 1, 0, 0): "\U0001fb09",
+    (1, 1, 0, 1, 0, 0): "\U0001fb0a",
+    (0, 0, 1, 1, 0, 0): "\U0001fb0b",
+    (1, 0, 1, 1, 0, 0): "\U0001fb0c",
+    (0, 1, 1, 1, 0, 0): "\U0001fb0d",
+    (1, 1, 1, 1, 0, 0): "\U0001fb0e",
+    (0, 0, 0, 0, 1, 0): "\U0001fb0f",
+    (1, 0, 0, 0, 1, 0): "\U0001fb10",
+    (0, 1, 0, 0, 1, 0): "\U0001fb11",
+    (1, 1, 0, 0, 1, 0): "\U0001fb12",
+    (0, 0, 1, 0, 1, 0): "\U0001fb13",
+    (1, 0, 1, 0, 1, 0): "\u258c",  # Exception
+    (0, 1, 1, 0, 1, 0): "\U0001fb14",
+    (1, 1, 1, 0, 1, 0): "\U0001fb15",
+    (0, 0, 0, 1, 1, 0): "\U0001fb16",
+    (1, 0, 0, 1, 1, 0): "\U0001fb17",
+    (0, 1, 0, 1, 1, 0): "\U0001fb18",
+    (1, 1, 0, 1, 1, 0): "\U0001fb19",
+    (0, 0, 1, 1, 1, 0): "\U0001fb1a",
+    (1, 0, 1, 1, 1, 0): "\U0001fb1b",
+    (0, 1, 1, 1, 1, 0): "\U0001fb1c",
+    (1, 1, 1, 1, 1, 0): "\U0001fb1d",
+    (0, 0, 0, 0, 0, 1): "\U0001fb1e",
+    (1, 0, 0, 0, 0, 1): "\U0001fb1f",
+    (0, 1, 0, 0, 0, 1): "\U0001fb20",
+    (1, 1, 0, 0, 0, 1): "\U0001fb21",
+    (0, 0, 1, 0, 0, 1): "\U0001fb22",
+    (1, 0, 1, 0, 0, 1): "\U0001fb23",
+    (0, 1, 1, 0, 0, 1): "\U0001fb24",
+    (1, 1, 1, 0, 0, 1): "\U0001fb25",
+    (0, 0, 0, 1, 0, 1): "\U0001fb26",
+    (1, 0, 0, 1, 0, 1): "\U0001fb27",
+    (0, 1, 0, 1, 0, 1): "\u2590",  # Exception
+    (1, 1, 0, 1, 0, 1): "\U0001fb28",
+    (0, 0, 1, 1, 0, 1): "\U0001fb29",
+    (1, 0, 1, 1, 0, 1): "\U0001fb2a",
+    (0, 1, 1, 1, 0, 1): "\U0001fb2b",
+    (1, 1, 1, 1, 0, 1): "\U0001fb2c",
+    (0, 0, 0, 0, 1, 1): "\U0001fb2d",
+    (1, 0, 0, 0, 1, 1): "\U0001fb2e",
+    (0, 1, 0, 0, 1, 1): "\U0001fb2f",
+    (1, 1, 0, 0, 1, 1): "\U0001fb30",
+    (0, 0, 1, 0, 1, 1): "\U0001fb31",
+    (1, 0, 1, 0, 1, 1): "\U0001fb32",
+    (0, 1, 1, 0, 1, 1): "\U0001fb33",
+    (1, 1, 1, 0, 1, 1): "\U0001fb34",
+    (0, 0, 0, 1, 1, 1): "\U0001fb35",
+    (1, 0, 0, 1, 1, 1): "\U0001fb36",
+    (0, 1, 0, 1, 1, 1): "\U0001fb37",
+    (1, 1, 0, 1, 1, 1): "\U0001fb38",
+    (0, 0, 1, 1, 1, 1): "\U0001fb39",
+    (1, 0, 1, 1, 1, 1): "\U0001fb3a",
+    (0, 1, 1, 1, 1, 1): "\U0001fb3b",
+    (1, 1, 1, 1, 1, 1): "\u2588",  # Exception
+}
+
+
+def _sixel_gen(m: MatrixType, sixels: SixelMapType = _sixels) -> Generator[str]:
+    n_rows = len(m)
+    n_cols = len(m[0])
+
+    def get(r: int, c: int) -> bool:
+        if r >= n_rows or c >= n_cols:
+            return False
+        return m[r][c]
+
+    for r in range(0, n_rows, 3):
+        for c in range(0, n_cols, 2):
+            sixel = (
+                get(r, c),
+                get(r, c + 1),
+                get(r + 1, c),
+                get(r + 1, c + 1),
+                get(r + 2, c),
+                get(r + 2, c + 1),
+            )
+            yield sixels[sixel]
+        yield "\n"
+
+
+def matrix_to_sixel(m: MatrixType) -> str:
+    return "".join(_sixel_gen(m))