dotfiles

---@brief
---
--- https://projects.eclipse.org/projects/eclipse.jdt.ls
---
--- Language server for Java.
---
--- ```lua
---   -- init.lua
---   vim.lsp.enable('jdtls')
--- ```
---
--- You can also pass extra custom jvm arguments with the JDTLS_JVM_ARGS environment variable as a space separated list of arguments,
--- that will be converted to multiple --jvm-arg=<param> args when passed to the jdtls script. This will allow for example tweaking
--- the jvm arguments or integration with external tools like lombok:
---
--- ```sh
--- export JDTLS_JVM_ARGS="-javaagent:$HOME/.local/share/java/lombok.jar"
--- ```
---
local function get_jdtls_cache_dir()
	return vim.fn.stdpath 'cache' .. '/jdtls'
end

local function get_jdtls_workspace_dir()
	return get_jdtls_cache_dir() .. '/workspace'
end

local function get_jdtls_jvm_args()
	local env = os.getenv 'JDTLS_JVM_ARGS'
	local args = {}
	for a in string.gmatch( (env or ''), '%S+' ) do
		local arg = string.format( '--jvm-arg=%s', a )
		table.insert( args, arg )
	end
	return unpack( args )
end

local root_markers1 = {
	-- Multi-module projects
	'mvnw',               -- Maven
	'gradlew',            -- Gradle
	'settings.gradle',    -- Gradle
	'settings.gradle.kts', -- Gradle
	-- Use git directory as last resort for multi-module maven projects
	-- In multi-module maven projects it is not really possible to determine what is the parent directory
	-- and what is submodule directory. And jdtls does not break if the parent directory is at higher level than
	-- actual parent pom.xml so propagating all the way to root git directory is fine
	'.git',
}
local root_markers2 = {
	-- Single-module projects
	'build.xml',       -- Ant
	'pom.xml',         -- Maven
	'build.gradle',    -- Gradle
	'build.gradle.kts', -- Gradle
}

---@type vim.lsp.Config
return {
	---@param dispatchers? vim.lsp.rpc.Dispatchers
	---@param config vim.lsp.ClientConfig
	cmd = function ( dispatchers, config )
		local workspace_dir = get_jdtls_workspace_dir()
		local data_dir = workspace_dir

		if config.root_dir then
			data_dir = data_dir .. '/' .. vim.fn.fnamemodify( config.root_dir, ':p:h:t' )
		end

		local config_cmd = {
			'jdtls',
			'-data',
			data_dir,
			get_jdtls_jvm_args(),
		}

		return vim.lsp.rpc.start( config_cmd, dispatchers, {
			cwd = config.cmd_cwd,
			env = config.cmd_env,
			detached = config.detached,
		} )
	end,
	filetypes = { 'java' },
	root_markers = { root_markers1, root_markers2 },
	init_options = {},
}