# colitur-x

A raw Xlib front-end for [colitur](../colitur): reads `colitur emit --format
csv` on stdin, draws the year as a month grid coloured by each day's
liturgical colour, and shows the selected day's readings underneath.

    make && make install          # into ~/.local/bin
    colitur emit --format csv --from 2027 --to 2027 | colitur-x

Keys: arrows or `hjkl` move, `n`/`p` change month, `q` quits.

It opens on **today** when the input covers it. Reading the clock is a
presentation choice and belongs in a viewer: colitur's own kernel is pure
and deliberately never asks what day it is, which is what lets it be tested
to the year 9999.

    colitur-x -g 1200x820 < day.csv          # preferred size, if the WM allows
    CX_DUMP=/tmp/f.ppm colitur-x < day.csv   # write one frame, then exit

The grid **fills whatever size it is given**: cell width is the window
divided seven ways, cell height six ways, and the number of lines a feast
name gets is whatever fits. Under a tiling window manager it therefore uses
its whole tile rather than sitting in a corner of one, and resizing reflows
instead of clipping. `config.h` sets minimums, not sizes.

It reads CSV on **stdin** and nothing else, so the shell decides what it
shows. One month:

    colitur emit --format csv --from 2027 --to 2027 | grep "^2027-04" | colitur-x

The header line is detected rather than assumed, so filtering it away is
fine. An earlier version skipped the first line unconditionally, which meant
that pipeline silently dropped 1 April -- the program fought the obvious
filter instead of composing with it.

Another language, or a local calendar:

    colitur emit --format csv --from 2027 --to 2027 --lang en | colitur-x
    colitur emit --format csv --from 2027 --to 2027 \
      --overlay ~/parish.sexp | colitur-x

With no input it says so and exits 2.

## Why it exists

colitur is a Unix tool: it computes and prints. This is a separate program
that composes with it, so colitur's own dependencies stay frozen
(`dune alcotest qcheck qcheck-alcotest sexplib ppx_sexp_conv`) and its
kernel stays pure.

## Build

    make

`-std=c99 -Os -Wall -Wextra`, linking libX11 and libXft. ~17 KB.

Configuration is compile-time, suckless style: edit `config.h` and rebuild.
There is deliberately no runtime config file — colitur itself owns the
calendar's configuration (language, sigla, overlays); this program owns only
how it is painted.

## Limits, stated rather than discovered

- X11 only. Runs under XWayland but is not a Wayland client.
- Read-only. It renders what colitur emits; it edits nothing.
- Xft is used for antialiasing and UTF-8. Dropping it for core X11 fonts
  would reduce the dependency list to libX11 and libc alone, at the cost of
  correct rendering for `æ`/`œ` and Polish diacritics. Not worth it.
- A tiling window manager will ignore the size hints and give the grid its
  own tile; the layout handles that, the empty space is the WM's choice.

## The microui variant

An editable front-end -- where year, language, book-name form and numbering
tradition are buttons that re-run colitur -- lives in
[colitur-experiments](../colitur-experiments) rather than here, so this repo
holds one finished program instead of a finished one and a sketch.

### Which to use

`colitur-x` renders; `colitur-mu` renders and lets you change the invocation.
Neither is the right answer for a non-technical user on a machine that is not
yours — both are X11-only and must be compiled. For that, a static site or a
small local web UI wins.