-- This is the same as in lspconfig.configs.jdtls, but avoids
-- needing to require that when this module loads.
local java_filetypes = { "java" }

-- Utility function to extend or override a config table, similar to the way
-- that Plugin.opts works.
---@param config table
---@param custom function | table | nil
local function extend_or_override(config, custom, ...)
  if type(custom) == "function" then
    config = custom(config, ...) or config
  elseif custom then
    config = vim.tbl_deep_extend("force", config, custom) --[[@as table]]
  end
  return config
end

return {
  recommended = function()
    return LazyVim.extras.wants({
      ft = "java",
      root = {
        "build.gradle",
        "build.gradle.kts",
        "build.xml", -- Ant
        "pom.xml", -- Maven
        "settings.gradle", -- Gradle
        "settings.gradle.kts", -- Gradle
      },
    })
  end,

  -- Add java to treesitter.
  {
    "nvim-treesitter/nvim-treesitter",
    opts = { ensure_installed = { "java" } },
  },

  -- Ensure java debugger and test packages are installed.
  {
    "mfussenegger/nvim-dap",
    optional = true,
    dependencies = {
      {
        "williamboman/mason.nvim",
        opts = { ensure_installed = { "java-debug-adapter", "java-test" } },
      },
    },
  },

  -- Configure nvim-lspconfig to install the server automatically via mason, but
  -- defer actually starting it to our configuration of nvim-jtdls below.
  {
    "neovim/nvim-lspconfig",
    opts = {
      -- make sure mason installs the server
      servers = {
        jdtls = {},
      },
      setup = {
        jdtls = function()
          return true -- avoid duplicate servers
        end,
      },
    },
  },

  -- Set up nvim-jdtls to attach to java files.
  {
    "mfussenegger/nvim-jdtls",
    dependencies = { "folke/which-key.nvim" },
    ft = java_filetypes,
    opts = function()
      local mason_registry = require("mason-registry")
      local lombok_jar = mason_registry.get_package("jdtls"):get_install_path() .. "/lombok.jar"
      return {
        -- How to find the root dir for a given filename. The default comes from
        -- lspconfig which provides a function specifically for java projects.
        root_dir = LazyVim.lsp.get_raw_config("jdtls").default_config.root_dir,

        -- How to find the project name for a given root dir.
        project_name = function(root_dir)
          return root_dir and vim.fs.basename(root_dir)
        end,

        -- Where are the config and workspace dirs for a project?
        jdtls_config_dir = function(project_name)
          return vim.fn.stdpath("cache") .. "/jdtls/" .. project_name .. "/config"
        end,
        jdtls_workspace_dir = function(project_name)
          return vim.fn.stdpath("cache") .. "/jdtls/" .. project_name .. "/workspace"
        end,

        -- How to run jdtls. This can be overridden to a full java command-line
        -- if the Python wrapper script doesn't suffice.
        cmd = {
          vim.fn.exepath("jdtls"),
          string.format("--jvm-arg=-javaagent:%s", lombok_jar),
        },
        full_cmd = function(opts)
          local fname = vim.api.nvim_buf_get_name(0)
          local root_dir = opts.root_dir(fname)
          local project_name = opts.project_name(root_dir)
          local cmd = vim.deepcopy(opts.cmd)
          if project_name then
            vim.list_extend(cmd, {
              "-configuration",
              opts.jdtls_config_dir(project_name),
              "-data",
              opts.jdtls_workspace_dir(project_name),
            })
          end
          return cmd
        end,

        -- These depend on nvim-dap, but can additionally be disabled by setting false here.
        dap = { hotcodereplace = "auto", config_overrides = {} },
        dap_main = {},
        test = true,
        settings = {
          java = {
            inlayHints = {
              parameterNames = {
                enabled = "all",
              },
            },
          },
        },
      }
    end,
    config = function(_, opts)
      -- Find the extra bundles that should be passed on the jdtls command-line
      -- if nvim-dap is enabled with java debug/test.
      local mason_registry = require("mason-registry")
      local bundles = {} ---@type string[]
      if opts.dap and LazyVim.has("nvim-dap") and mason_registry.is_installed("java-debug-adapter") then
        local java_dbg_pkg = mason_registry.get_package("java-debug-adapter")
        local java_dbg_path = java_dbg_pkg:get_install_path()
        local jar_patterns = {
          java_dbg_path .. "/extension/server/com.microsoft.java.debug.plugin-*.jar",
        }
        -- java-test also depends on java-debug-adapter.
        if opts.test and mason_registry.is_installed("java-test") then
          local java_test_pkg = mason_registry.get_package("java-test")
          local java_test_path = java_test_pkg:get_install_path()
          vim.list_extend(jar_patterns, {
            java_test_path .. "/extension/server/*.jar",
          })
        end
        for _, jar_pattern in ipairs(jar_patterns) do
          for _, bundle in ipairs(vim.split(vim.fn.glob(jar_pattern), "\n")) do
            table.insert(bundles, bundle)
          end
        end
      end

      local function attach_jdtls()
        local fname = vim.api.nvim_buf_get_name(0)

        -- Configuration can be augmented and overridden by opts.jdtls
        local config = extend_or_override({
          cmd = opts.full_cmd(opts),
          root_dir = opts.root_dir(fname),
          init_options = {
            bundles = bundles,
          },
          settings = opts.settings,
          -- enable CMP capabilities
          capabilities = LazyVim.has("cmp-nvim-lsp") and require("cmp_nvim_lsp").default_capabilities() or nil,
        }, opts.jdtls)

        -- Existing server will be reused if the root_dir matches.
        require("jdtls").start_or_attach(config)
        -- not need to require("jdtls.setup").add_commands(), start automatically adds commands
      end

      -- Attach the jdtls for each java buffer. HOWEVER, this plugin loads
      -- depending on filetype, so this autocmd doesn't run for the first file.
      -- For that, we call directly below.
      vim.api.nvim_create_autocmd("FileType", {
        pattern = java_filetypes,
        callback = attach_jdtls,
      })

      -- Setup keymap and dap after the lsp is fully attached.
      -- https://github.com/mfussenegger/nvim-jdtls#nvim-dap-configuration
      -- https://neovim.io/doc/user/lsp.html#LspAttach
      vim.api.nvim_create_autocmd("LspAttach", {
        callback = function(args)
          local client = vim.lsp.get_client_by_id(args.data.client_id)
          if client and client.name == "jdtls" then
            local wk = require("which-key")
            wk.add({
              {
                mode = "n",
                buffer = args.buf,
                { "<leader>cx", group = "extract" },
                { "<leader>cxv", require("jdtls").extract_variable_all, desc = "Extract Variable" },
                { "<leader>cxc", require("jdtls").extract_constant, desc = "Extract Constant" },
                { "gs", require("jdtls").super_implementation, desc = "Goto Super" },
                { "gS", require("jdtls.tests").goto_subjects, desc = "Goto Subjects" },
                { "<leader>co", require("jdtls").organize_imports, desc = "Organize Imports" },
              },
            })
            wk.add({
              {
                mode = "v",
                buffer = args.buf,
                { "<leader>cx", group = "extract" },
                {
                  "<leader>cxm",
                  [[<ESC><CMD>lua require('jdtls').extract_method(true)<CR>]],
                  desc = "Extract Method",
                },
                {
                  "<leader>cxv",
                  [[<ESC><CMD>lua require('jdtls').extract_variable_all(true)<CR>]],
                  desc = "Extract Variable",
                },
                {
                  "<leader>cxc",
                  [[<ESC><CMD>lua require('jdtls').extract_constant(true)<CR>]],
                  desc = "Extract Constant",
                },
              },
            })

            if opts.dap and LazyVim.has("nvim-dap") and mason_registry.is_installed("java-debug-adapter") then
              -- custom init for Java debugger
              require("jdtls").setup_dap(opts.dap)
              require("jdtls.dap").setup_dap_main_class_configs(opts.dap_main)

              -- Java Test require Java debugger to work
              if opts.test and mason_registry.is_installed("java-test") then
                -- custom keymaps for Java test runner (not yet compatible with neotest)
                wk.add({
                  {
                    mode = "n",
                    buffer = args.buf,
                    { "<leader>t", group = "test" },
                    {
                      "<leader>tt",
                      function()
                        require("jdtls.dap").test_class({
                          config_overrides = type(opts.test) ~= "boolean" and opts.test.config_overrides or nil,
                        })
                      end,
                      desc = "Run All Test",
                    },
                    {
                      "<leader>tr",
                      function()
                        require("jdtls.dap").test_nearest_method({
                          config_overrides = type(opts.test) ~= "boolean" and opts.test.config_overrides or nil,
                        })
                      end,
                      desc = "Run Nearest Test",
                    },
                    { "<leader>tT", require("jdtls.dap").pick_test, desc = "Run Test" },
                  },
                })
              end
            end

            -- User can set additional keymaps in opts.on_attach
            if opts.on_attach then
              opts.on_attach(args)
            end
          end
        end,
      })

      -- Avoid race condition by calling attach the first time, since the autocmd won't fire.
      attach_jdtls()
    end,
  },
}