feat(nvim-setcellwidths-table-for-udev-gothic): new

3 files changed, 169 insertions, 0 deletions

diff --git a/default.nix b/default.nix
index 2f4443e..aded4de 100644
--- a/default.nix
+++ b/default.nix
@@ -6,6 +6,7 @@
   hgrep = pkgs.callPackage ./pkgs/hgrep { };
 
   git-helpers = pkgs.callPackage ./pkgs/git-helpers { };
+  nvim-setcellwidths-table-for-udev-gothic = pkgs.callPackage ./pkgs/nvim-setcellwidths-table-for-udev-gothic { };
   reparojson = pkgs.callPackage ./pkgs/reparojson { };
   term-banner = pkgs.callPackage ./pkgs/term-banner { };
   term-clock = pkgs.callPackage ./pkgs/term-clock { };
diff --git a/pkgs/nvim-setcellwidths-table-for-udev-gothic/default.nix b/pkgs/nvim-setcellwidths-table-for-udev-gothic/default.nix
new file mode 100644
index 0000000..18df323
--- /dev/null
+++ b/pkgs/nvim-setcellwidths-table-for-udev-gothic/default.nix
@@ -0,0 +1,31 @@
+{
+  lib,
+  stdenv,
+  python3,
+  udev-gothic,
+}:
+
+stdenv.mkDerivation {
+  pname = "nvim-setcellwidths-table-for-udev-gothic";
+  version = "1.0.0";
+
+  src = ./.;
+
+  nativeBuildInputs = [
+    (python3.withPackages (ps: [ ps.fonttools ]))
+  ];
+
+  buildPhase = ''
+    python main.py ${udev-gothic}/share/fonts/udev-gothic/UDEVGothic35-Regular.ttf > setcellwidths.lua
+  '';
+
+  installPhase = ''
+    mkdir -p $out
+    cp setcellwidths.lua $out
+  '';
+
+  meta = with lib; {
+    description = "Generate setcellwidths() table for udev-gothic font";
+    license = licenses.ofl;
+  };
+}
diff --git a/pkgs/nvim-setcellwidths-table-for-udev-gothic/main.py b/pkgs/nvim-setcellwidths-table-for-udev-gothic/main.py
new file mode 100644
index 0000000..483d826
--- /dev/null
+++ b/pkgs/nvim-setcellwidths-table-for-udev-gothic/main.py
@@ -0,0 +1,137 @@
+import argparse
+from collections.abc import Generator
+from fontTools.ttLib import TTFont
+from pathlib import Path
+import unicodedata
+
+def ambiguous_codepoints() -> Generator[int]:
+    for cp in range(0x00000, 0x30000):
+        try:
+            char = chr(cp)
+            eaw = unicodedata.east_asian_width(char)
+            if eaw == 'A':
+                yield cp
+        except (ValueError, UnicodeEncodeError):
+            continue
+
+def get_glyph_width(font: TTFont, codepoint: int) -> int | None:
+    cmap = font.getBestCmap()
+    if cmap is None:
+        return None
+
+    glyph_name = cmap.get(codepoint)
+    if glyph_name is None:
+        return None
+
+    if 'hmtx' not in font:
+        return None
+
+    hmtx = font['hmtx']
+    if glyph_name not in hmtx.metrics:
+        return None
+
+    width, _ = hmtx.metrics[glyph_name]
+    return width
+
+def get_reference_widths(font: TTFont) -> tuple[int | None, int | None]:
+    halfwidth_ref = None
+    for cp in [0x0041, 0x0030, 0x0061]:
+        w = get_glyph_width(font, cp)
+        if w is not None and w > 0:
+            halfwidth_ref = w
+            break
+
+    fullwidth_ref = None
+    for cp in [0xFF21, 0x3042, 0x6F22, 0x4E00]:
+        w = get_glyph_width(font, cp)
+        if w is not None and w > 0:
+            fullwidth_ref = w
+            break
+
+    return halfwidth_ref, fullwidth_ref
+
+def classify_width(width: int, half_ref: int, full_ref: int) -> str:
+    if width <= (half_ref + full_ref) / 2:
+        return "half"
+    else:
+        return "full"
+
+def analyze_font(font_path: str) -> dict:
+    font = TTFont(font_path)
+
+    stats = {
+        "half": [],
+        "full": [],
+    }
+
+    half_ref, full_ref = get_reference_widths(font)
+    if half_ref is None or full_ref is None:
+        return stats
+
+    for cp in ambiguous_codepoints():
+        width = get_glyph_width(font, cp)
+        if width is None:
+            continue
+
+        classification = classify_width(width, half_ref, full_ref)
+        stats[classification].append(cp)
+
+    font.close()
+    return stats
+
+def merge_ranges(codepoints: list[int]) -> list[tuple[int, int]]:
+    if not codepoints:
+        return []
+    sorted_cps = sorted(codepoints)
+    ranges = []
+    start = sorted_cps[0]
+    end = sorted_cps[0]
+    for cp in sorted_cps[1:]:
+        if cp == end + 1:
+            end = cp
+        else:
+            ranges.append((start, end))
+            start = cp
+            end = cp
+    ranges.append((start, end))
+    return ranges
+
+def generate_table(stats: dict) -> str:
+    prefix = [
+        "local M = {}",
+        "",
+        "function M.setcellwidths()",
+        "   vim.fn.setcellwidths({",
+    ]
+    table = []
+    for start, end in merge_ranges(stats["full"]):
+        chars = ", ".join("%s (U+%04X)" % (chr(cp), cp) for cp in range(start, end + 1))
+        table.append("      -- %s" % chars)
+        table.append("      {%#06x, %#06x, 2}," % (start, end))
+    suffix = [
+        "   })",
+        "end",
+        "",
+        "return M",
+    ]
+    return "\n".join(prefix + table + suffix)
+
+def main():
+    parser = argparse.ArgumentParser(
+        description='Generate Neovim setcellwidths() table'
+    )
+    parser.add_argument('font', help='Font file path')
+
+    args = parser.parse_args()
+
+    if not Path(args.font).exists():
+        print(f"Font file not found: {args.font}")
+        return 1
+
+    stats = analyze_font(args.font)
+    table = generate_table(stats)
+    print(table)
+    return 0
+
+if __name__ == '__main__':
+    exit(main())