# Dictionary data

## Korean Hanja data

`hanja.src` is the tracked, reviewable source for Korean Hanja conversion.
Every data row is exactly one Hanja character, a tab, and one modern Hangul
syllable:

```
漢	한
```

It contains no word rows such as `견출지` or `방학`.  `mkhanja` validates this
contract and groups rows by their Hangul reading to produce the existing
runtime dictionary format.  Candidate order follows source order.  The source
keeps all retained pairs for review; the generated dictionary stores the first
128 candidates per reading because that is the engine's lookup limit.

The source is derived from libhangul release tag `libhangul-0.2.0`.  The
annotated tag object is `20afc38922e3595ee3ed5b186f2ea05afe663763`, its
peeled commit is `41c702f5d3581325b646ef6249f1f641b0427ae0`, and
`data/hanja/hanja.txt` has blob ID
`199cfd70c4b306257ac2e018714a1285f7cf0ed3`.  Import and regenerate it from
the repository root with:

```sh
curl -L https://raw.githubusercontent.com/libhangul/libhangul/41c702f5d3581325b646ef6249f1f641b0427ae0/data/hanja/hanja.txt -o upstream
printf '%s  %s\n' dd44dcc856cf542b1022d0f39c2e9b9f8805fdcc5923be80f04849ed97ce0996 upstream | sha256sum -c -
map/libhangul2hanja upstream >map/hanja.src
map/mkhanja >map/hanja.dict
```

`libhangul2hanja` retains only rows whose reading is one modern Hangul
syllable and whose value is one Hanja character supported by the current
popup: U+3400–U+4DBF, U+4E00–U+9FFF, or U+F900–U+FAFF.  Thus word readings,
multi-character values, jamo readings, and supplementary-plane ideographs
are omitted.  The import preserves the upstream license header and row order.
The retained data is BSD 3-Clause licensed by Choe Hwanjin; the complete text
is in `LICENSES/BSD-3-Clause-libhangul-hanja.txt`.

## Japanese romaji

`hira.map` and `kata.map` are Mozc's default romaji table, one row per key,
in gojūon order; `kata.map` is the same table in Katakana, and
`make verify-map` checks that the two have the same keys.  A doubled
consonant, or `tch`, maps to っ and keeps the consonant pending; the engine
knows that rule, the table only lists the rows.

## Japanese dictionary data

`kanji.dict` is the historical dictionary bundled with strans.  Its own header
identifies it as the SKK Medium dictionary, version 8.1 of May 24, 1995,
rearranged for Plan 9 ktrans by Kenji Okamoto on February 17, 2000.  It was
already present when this repository was created in commit
`dcd1147638f908eca7e4b7616815e215022cc99d` on December 23, 2025.  No original
SKK input file or upstream revision was committed, so the current file cannot
honestly be regenerated byte-for-byte from repository artifacts.  The license
notice in its header permits redistribution and modification under GPL version
2 or later.

The repository copy keeps that historical candidate order.  Duplicate keys
were merged at their first occurrence, later unseen candidates were appended
in source order, duplicate candidates were removed, and the empty
`ようたつ` row was removed.

## Importing a current SKK dictionary

From the repository root, fetch a known upstream revision and convert it with:

```
git clone https://github.com/skk-dev/dict.git map/skkdicts
git -C map/skkdicts checkout --detach REVISION
map/skk2ktrans map/skkdicts/SKK-JISYO.M >map/kanji.dict.new
python3 map/verifymap.py map/kanji.dict.new
```

Use a full skk-dev/dict commit ID for `REVISION` and record it when replacing
the bundled data.  Git is needed only to fetch upstream data; it is not part of
the normal build image.

`skk2ktrans` accepts one or more EUC-JP SKK files (or standard input), writes
UTF-8 tab-separated rows, and merges input in command-line and source order.
It strips annotations, deduplicates candidates, and omits candidates containing
whitespace.  Rows containing expressions or escaped candidate delimiters are
rejected; rewrite or omit those rows before import.

`verifymap.py` checks UTF-8, row structure, unique keys, 64-rune keys and
values, canonical candidate spacing, and duplicate dictionary candidates.
Pass it the exact `.map` and `.dict` files used for runtime or validation.
The normal build does not install map data.