feat: 用 lua_filter 固定字词的顺序（暂时未启用） close #586

lua/pin_cand_filter.lua

@@ -0,0 +1,87 @@
+-- 置顶候选项
+
+local function isInList(list, str)
+	for i, v in ipairs(list) do
+		if v == str then
+			return true, i
+		end
+	end
+	return false, 0
+end
+
+local M = {}
+
+function M.init(env)
+	local config = env.engine.schema.config
+	env.name_space = env.name_space:gsub("^*", "")
+	-- 遍历要置顶的候选项列表，将其转换为 table 存储到 M.pin_cands
+	-- 'ta	他 她 它' → M.pin_cands["ta"] = {"他", "她", "它"},
+	-- 'ni hao	你好 拟好' → M.pin_cands["ni hao"] = {"你好", "拟好"}
+	local list = config:get_list(env.name_space)
+	M.pin_cands = {}
+	for i = 0, list.size - 1 do
+		local code, texts = list:get_value_at(i).value:match("([^\t]+)\t(.+)")
+		if code and texts then
+			M.pin_cands[code] = {}
+			for text in texts:gmatch("%S+") do
+				table.insert(M.pin_cands[code], text)
+			end
+		end
+	end
+end
+
+function M.func(input)
+	local pined = {}
+	local others = {}
+	local pined_count = 0
+	for cand in input:iter() do
+		local pins = M.pin_cands[cand.preedit]
+		if pins then
+			-- 给 pined 几个空字符串占位元素，后面直接 pined[idx] = cand 确保 pined 与 pins 顺序一致
+			if #pined < #pins then
+				for _ = 1, #pins do
+					table.insert(pined, '')
+				end
+			end
+			-- 要置顶的放到 pined 中，其余的放到 others
+			local ok, idx = isInList(pins, cand.text)
+			if ok then
+				pined[idx] = cand
+				pined_count = pined_count + 1
+			else
+				table.insert(others, cand)
+			end
+			-- 找齐了或者 others 太大了，就不找了，一般前 5 个就找完了
+			if pined_count == #pins or #others > 50 then
+				break
+			end
+		else
+			table.insert(others, cand)
+			break
+		end
+	end
+
+	-- yield pined others 及后续的候选项
+	if pined_count > 0 then
+		-- 如果因配置写了这个编码没有的字词，导致没有找齐，删掉空字符串占位元素
+		local i = 1
+		while i <= #pined do
+			if pined[i] == '' then
+				table.remove(pined, i)
+			else
+				i = i + 1
+			end
+		end
+		for _, cand in ipairs(pined) do
+			yield(cand)
+		end
+	end
+	for _, cand in ipairs(others) do
+		yield(cand)
+	end
+	for cand in input:iter() do
+		yield(cand)
+	end
+end
+
+return M