init.lua

VERSION = "0.0.7"

local micro = import("micro")
local config = import("micro/config")
local buffer = import("micro/buffer")

local plug_path = config.ConfigDir .. "/plug/?.lua"
if not package.path:find(plug_path, 1, true) then
	package.path = package.path .. ";" .. plug_path
end

local bell = require("skk/bell")
local download = require("skk/download")
local romaji = require("skk/romaji")
local jisyo = require("skk/jisyo")
local kana = require("skk/kana")

local d

-- internal constants
local TEXT_EVENT_INSERT = 1
local TEXT_EVENT_REPLACE = 0
local TEXT_EVENT_REMOVE = -1

-- romaji modes
local DIRECT_MODE = 0 -- no conversion
local HIRAGANA_MODE = 1
local KATAKANA_MODE = 2
local ALPHABET_MODE = 3 -- wide alphabet

-- conversion modes
local CONV_NONE = 0
local CONV_START = 1
local CONV_OKURI = 2
local CONV_ENGLISH = 3

-- states
local romaji_mode = DIRECT_MODE
local kana_buffer = ""
local conv_mode = CONV_NONE
local conv_buffer = ""
local conv_list = nil
local conv_index = 1
local conv_cand = ""
local conv_okuri = ""

local function show_mode()
	local mark
	if romaji_mode == DIRECT_MODE then
		mark = "aA"
	elseif romaji_mode == HIRAGANA_MODE then
		mark = "あ"
	elseif romaji_mode == KATAKANA_MODE then
		mark = "ア"
	elseif romaji_mode == ALPHABET_MODE then
		mark = "ａＡ"
	else
		bell.program_error("invalid romaji_mode == " .. romaji_mode)
		return
	end

	local head = ""
	if conv_mode ~= CONV_NONE then
		if #conv_cand > 0 then
			head = "▼" .. conv_cand
		else
			head = "▽" .. conv_buffer
		end
	end

	local buf
	if #conv_okuri > 0 then
		buf = conv_okuri
	else
		buf = kana_buffer
	end

	micro.InfoBar():Message("[" .. mark .. "]" .. head .. buf)
end

local function reset_conv()
	conv_mode = CONV_NONE
	conv_buffer = ""
	conv_list = nil
	conv_index = 1
	conv_cand = ""
	conv_okuri = ""
end

function Skk()
	if not d then
		d, err = jisyo.open(config.ConfigDir .. "/skk-dict/SKK-JISYO.L.cdb")
		if err then
			micro.InfoBar():Error("Error in loading SKK dictionaries.")
		end
	end

	if conv_mode ~= CONV_NONE then
		local out = (conv_cand ~= "" and conv_cand) or conv_buffer
		out = out .. conv_okuri
		if #out > 0 then
			local buf = micro.CurPane().Buf
			local cursor = buf:GetActiveCursor()
			local loc = buffer.Loc(cursor.X, cursor.Y)
			micro.CurPane().Buf:Insert(loc, out)
		end
	end

	romaji_mode = HIRAGANA_MODE
	kana_buffer = ""

	reset_conv()

	if d then
		show_mode()
	end
end

function SkkDirect(pane)
	romaji_mode = DIRECT_MODE
	kana_buffer = ""

	if conv_mode ~= CONV_NONE then
		local out = conv_cand ~= "" and conv_cand or conv_buffer
		out = out .. conv_okuri

		if #out > 0 then
			local buf = pane.Buf
			local cursor = buf:GetActiveCursor()
			local loc = buffer.Loc(cursor.X, cursor.Y)
			micro.CurPane().Buf:Insert(loc, out)
		end

		reset_conv()
	end

	show_mode()
	return
end

function SkkGet()
	download.defaults()
end

local function bytes_to_string(array)
	local buf = {}
	for i = 1, #array do
		table.insert(buf, string.char(array[i]))
	end
	return table.concat(buf)
end

local function utf8_chop(s)
	local i = #s
	while i > 0 do
		local b = s:byte(i)
		if b < 128 or b >= 192 then
			return s:sub(1, i - 1)
		end
		i = i - 1
	end
	return ""
end

local vowels = {
	["あ"] = "a",
	["い"] = "i",
	["う"] = "u",
	["え"] = "e",
	["お"] = "o",
}

function onBeforeTextEvent(buf, ev)
	if romaji_mode == DIRECT_MODE then
		return true
	end

	-- expects only backspace
	if ev.EventType == TEXT_EVENT_REMOVE then
		if #kana_buffer > 0 then
			kana_buffer = string.sub(kana_buffer, 1, -2)
			show_mode()

			local cursor = micro.CurPane().Buf:GetActiveCursor()
			cursor:ResetSelection()
			cursor.X = cursor.X + 1
			return false
		elseif #conv_okuri > 0 then
			conv_okuri = utf8_chop(conv_okuri)
			show_mode()

			local cursor = micro.CurPane().Buf:GetActiveCursor()
			cursor:ResetSelection()
			cursor.X = cursor.X + 1
			return false
		elseif conv_mode ~= CONV_NONE and #conv_buffer > 0 then
			conv_buffer = utf8_chop(conv_buffer)
			if #conv_buffer < 1 then
				conv_mode = CONV_NONE
			end
			conv_list = nil
			conv_index = 1
			conv_cand = ""
			show_mode()

			local cursor = micro.CurPane().Buf:GetActiveCursor()
			cursor:ResetSelection()
			cursor.X = cursor.X + 1
			return false
		else
			show_mode()
			return true
		end
	end

	if ev.EventType == TEXT_EVENT_REPLACE then
		return true
	end

	-- assert
	if ev.EventType ~= TEXT_EVENT_INSERT then
		bell.program_error("invalid ev.EventType == " .. ev.EventType)
		return true
	end

	if #ev.Deltas ~= 1 then
		return true
	end
	local delta = ev.Deltas[1]
	local output = ""

	-- Text is byte array
	local text = bytes_to_string(delta.Text)
	-- pass through pasted long text
	if #text ~= 1 then
		return true
	end

	if romaji_mode == ALPHABET_MODE then
		local alphabet = romaji.to_alphabet[text]
		if alphabet then
			delta.Text = output .. alphabet
		end
		return true
	end

	-- now in Hiragana or Katakana mode

	if text == "L" then
		romaji_mode = ALPHABET_MODE
		kana_buffer = ""

		if conv_mode ~= CONV_NONE then
			local out = conv_cand ~= "" and conv_cand or conv_buffer
			out = out .. conv_okuri
			output = output .. out
			reset_conv()
		end

		show_mode()
		delta.Text = output
		return true
	end

	if text == "\n" and conv_mode ~= CONV_NONE then
		local out = conv_cand ~= "" and conv_cand or conv_buffer
		out = out .. conv_okuri
		output = output .. out
		reset_conv()

		show_mode()
		delta.Text = output
		return true
	end

	if text == " " and conv_mode ~= CONV_NONE then
		if not d then
			micro.InfoBar():Message("No SKK dictionaries.")
			delta.Text = output
			return true
		end

		if not conv_list then
			if conv_mode == CONV_OKURI then
				conv_list = d:lookup_okuri(conv_buffer)
			else
				conv_list = d:lookup(conv_buffer)
			end
			conv_index = 1
			if #conv_list < 1 then
				micro.InfoBar():Message("SKK: 候補なし")
				delta.Text = output
				return true
			end
		else
			conv_index = conv_index + 1
			if conv_index > #conv_list then
				conv_index = #conv_list
			end
		end
		conv_cand = conv_list[conv_index] or ""
		conv_cand = conv_cand:match("^([^;]*)")

		show_mode()
		delta.Text = output
		return true
	end

	if text == "x" and conv_list then
		conv_index = conv_index - 1
		if conv_index < 1 then
			conv_list = nil
			conv_index = 1
			conv_cand = ""
			conv_okuri = ""
		else
			conv_cand = conv_list[conv_index] or ""
			conv_cand = conv_cand:match("^([^;]*)")
		end

		show_mode()
		delta.Text = output
		return true
	end

	if text == "/" then
		if conv_list then
			local out = conv_cand ~= "" and conv_cand or conv_buffer
			out = out .. conv_okuri
			output = output .. out
			reset_conv()
		end

		conv_mode = CONV_ENGLISH

		show_mode()
		delta.Text = output
		return true
	end

	if conv_mode == CONV_ENGLISH then
		if conv_list then
			local out = conv_cand ~= "" and conv_cand or conv_buffer
			out = out .. conv_okuri
			output = output .. out
			reset_conv()
		else
			conv_buffer = conv_buffer .. text

			show_mode()
			delta.Text = output
			return true
		end
	end

	if #conv_cand > 0 then
		if conv_mode == CONV_OKURI then
			if #conv_okuri > 0 and not conv_okuri:match("っ$") and not conv_okuri:match("ッ$") then
				output = output .. conv_cand .. conv_okuri
				reset_conv()
				kana_buffer = ""
			end
		else
			output = output .. conv_cand .. conv_okuri
			reset_conv()
		end
	end

	if text:match("^[A-Z]$") then
		if conv_mode == CONV_NONE then
			conv_mode = CONV_START
		elseif conv_mode == CONV_START then
			conv_mode = CONV_OKURI
		end
		text = text:lower()
	end

	local kigou = romaji.to_kigou[text]
	if kigou then
		if conv_mode ~= CONV_NONE and kigou == "ー" then
			if not conv_list then
				conv_buffer = conv_buffer .. kigou
				show_mode()
				delta.Text = output
				return true
			end
		end

		kana_buffer = ""
		show_mode()
		delta.Text = output .. kigou
		return true
	end

	if not text:match("^%a$") then
		if conv_mode ~= CONV_NONE then
			local out = conv_cand ~= "" and conv_cand or conv_buffer
			out = out .. conv_okuri
			output = output .. out
			reset_conv()
		end

		if #output > 0 then
			show_mode()
		end
		delta.Text = output .. text
		return true
	end

	if text == "l" then
		romaji_mode = DIRECT_MODE
		kana_buffer = ""

		if conv_mode ~= CONV_NONE then
			local out = conv_cand ~= "" and conv_cand or conv_buffer
			out = out .. conv_okuri
			output = output .. out
			reset_conv()
		end

		show_mode()
		delta.Text = output
		return true
	end

	if text == "q" then
		if conv_mode == CONV_NONE then
			if romaji_mode == HIRAGANA_MODE then
				romaji_mode = KATAKANA_MODE
			elseif romaji_mode == KATAKANA_MODE then
				romaji_mode = HIRAGANA_MODE
			else
				bell.program_error("q: invalid romaji_mode == " .. romaji_mode)
				return true
			end
			show_mode()
			delta.Text = output
			return true
		elseif conv_mode == CONV_START then
			if romaji_mode == HIRAGANA_MODE then
				local kata = kana.to_kata(conv_buffer)
				conv_list = { kata }
				conv_index = 1
				conv_cand = kata
			elseif romaji_mode == KATAKANA_MODE then
				local hira = kana.to_hira(conv_buffer)
				conv_list = { hira }
				conv_index = 1
				conv_cand = hira
			else
				bell.program_error("q (conv): invalid romaji_mode == " .. romaji_mode)
				return true
			end
			show_mode()
			delta.Text = output
			return true
		end
	end

	kana_buffer = kana_buffer .. text

	local kana
	if romaji.is_sokuon[kana_buffer] then
		if romaji_mode == HIRAGANA_MODE then
			kana = "っ"
		elseif romaji_mode == KATAKANA_MODE then
			kana = "ッ"
		else
			bell.program_error("sokuon: invalid romaji_mode == " .. romaji_mode)
			kana = nil
		end
		kana_buffer = string.sub(kana_buffer, 2)
	elseif romaji.is_n[kana_buffer] then
		if romaji_mode == HIRAGANA_MODE then
			kana = "ん"
		elseif romaji_mode == KATAKANA_MODE then
			kana = "ン"
		else
			bell.program_error("n: invalid romaji_mode == " .. romaji_mode)
			kana = nil
		end
		kana_buffer = string.sub(kana_buffer, 2)
	else
		local lookup = kana_buffer
		if romaji.aliases[lookup] then
			lookup = romaji.aliases[lookup]
		end

		if romaji_mode == HIRAGANA_MODE then
			kana = romaji.to_hiragana[lookup]
		elseif romaji_mode == KATAKANA_MODE then
			kana = romaji.to_katakana[lookup]
		else
			bell.program_error("kana: invalid romaji_mode == " .. romaji_mode)
			kana = nil
		end
		if kana then
			kana_buffer = ""
		end
	end

	if conv_mode == CONV_NONE then
		if kana then
			delta.Text = output .. kana
		else
			delta.Text = output
		end
		show_mode()
		return true
	elseif conv_mode == CONV_START then
		if kana then
			conv_buffer = conv_buffer .. kana
			conv_list = nil
			conv_index = 1
			conv_cand = ""
		end
		show_mode()
		delta.Text = output
		return true
	elseif conv_mode == CONV_OKURI then
		local vowel = vowels[kana]
		if vowel then
			conv_buffer = conv_buffer .. vowel
			conv_okuri = conv_okuri .. kana
		elseif kana then
			conv_okuri = conv_okuri .. kana
		else
			conv_buffer = conv_buffer .. text
		end

		if not d then
			micro.InfoBar():Message("Please wait.. Loading SKK dictionaries..")
			delta.Text = output
			return true
		end

		conv_list = d:lookup_okuri(conv_buffer)

		conv_index = 1
		conv_cand = conv_list[conv_index] or ""
		conv_cand = conv_cand:match("^([^;]*)")

		show_mode()
		delta.Text = output
		return true
	else
		bell.program_error("onBeforeTextEvent: invalid conv_mode == " .. conv_mode)
		return true
	end
end

function init()
	config.MakeCommand("skk", Skk, config.NoComplete)
	config.MakeCommand("skkdirect", SkkDirect, config.NoComplete)
	config.MakeCommand("skkget", SkkGet, config.NoComplete)
	config.TryBindKey("Ctrl-j", "lua:skk.Skk", false)
	config.AddRuntimeFile("skk", config.RTHelp, "help/skk.md")
end