.files/.config/nvim/plugin/lsp.lua

local map = vim.keymap.set

----------------------
-- Language servers --
----------------------
-- NOTE: put settings into `settings`
-- use another `on_attach` field if needed
local servers = {
    clangd = {}, -- C/CPP
    cssls = {}, -- CSS
    html = {}, -- HTML
    jsonls = {}, -- JSON
    lemminx = {}, -- XML
    phpactor = {}, -- PHP
    pylsp = {}, -- Python
    pyright = {},
    taplo = {}, -- TOML
    texlab = {}, -- texlab
    ts_ls = {}, -- TypeScript
    vimls = {}, -- Vim Script
    ocamllsp = {}, -- OCaml
    gleam = {}, -- Gleam
    yamlls = {}, -- yaml
    gopls = {}, -- Golang
    elmls = {}, -- elm

    -- -- fix this, it shows spamming message on top
    -- golangci_lint_ls = {},

    fish_lsp = {},

    bashls = { -- Bash
        on_attach = function(_, bufno)
            map("n", "<leader>f", function()
                local saved = vim.fn.winsaveview()
                vim.cmd([[silent exec "%!shfmt"]])
                vim.fn.winrestview(saved)
            end, { buffer = bufno })
        end,
    },

    tinymist = {
        on_attach = function(_, bufno)
            map("n", "<leader>f", function()
                local saved = vim.fn.winsaveview()
                vim.cmd([[silent exec "%!typstyle -c 100"]])
                vim.fn.winrestview(saved)
            end, { buffer = bufno })
        end,
    },

    lua_ls = { -- Lua
        on_attach = function(_, bufno)
            map("n", "<leader>f", function()
                local saved = vim.fn.winsaveview()
                vim.cmd([[silent exec "!stylua %"]])
                vim.fn.winrestview(saved)
            end, { buffer = bufno })
        end,
        settings = {
            Lua = {
                workspace = {
                    checkThirdParty = "Disable",
                    library = { vim.env.VIMRUNTIME },
                },
            },
        },
    },

    nil_ls = { -- Nix
        settings = { ["nil"] = { formatting = { command = { "alejandra" } } } },
    },
}

-------------
-- Helpers --
-------------
vim.diagnostic.config {
    signs = {
        text = {
            [vim.diagnostic.severity.ERROR] = "E",
            [vim.diagnostic.severity.WARN] = "W",
            [vim.diagnostic.severity.INFO] = "H",
            [vim.diagnostic.severity.HINT] = "·",
        },
    },
    severity_sort = true,
    underline = {
        severity = {
            vim.diagnostic.severity.ERROR,
            vim.diagnostic.severity.WARN,
        },
    },
}

-- Helix style border
local border = {
    { " ", "FloatBorder" },
    { " ", "FloatBorder" },
    { " ", "FloatBorder" },
    { " ", "FloatBorder" },
    { " ", "FloatBorder" },
    { " ", "FloatBorder" },
    { " ", "FloatBorder" },
    { " ", "FloatBorder" },
}
local orig_util_open_floating_preview = vim.lsp.util.open_floating_preview
function vim.lsp.util.open_floating_preview(contents, syntax, opts, ...)
    opts = opts or {}
    opts.border = border
    return orig_util_open_floating_preview(contents, syntax, opts, ...)
end

-- Set log level
vim.lsp.set_log_level("off")

-- Capabilities
local capabilities = vim.lsp.protocol.make_client_capabilities()
capabilities = require("cmp_nvim_lsp").default_capabilities(capabilities)

----------
-- Init --
----------
require("fidget").setup()

local mylsp = require("lsp")

for name, config in pairs(servers) do
    require("lspconfig")[name].setup {
        capabilities = capabilities,
        settings = config.settings,
        -- NOTE: https://github.com/neovim/neovim/issues/30675
        offset_encoding = config.offset_encoding or "utf-8",
        on_attach = function(client, bufno)
            mylsp.on_attach(client, bufno);
            (config.on_attach or function(...) end)(client, bufno)
        end,
    }
end

------------------------
-- Standalone plugins --
------------------------
-- Java
local config = {
    on_attach = mylsp.on_attach,
    capabilities = capabilities,
    cmd = {
        -- https://github.com/NixOS/nixpkgs/issues/232822#issuecomment-1564243667
        -- `-data` argument is necessary
        "jdtls",
        "-data",
        vim.fn.expand("~/.cache/jdtls") .. vim.fn.expand("%:p:h"),
    },
    root_dir = vim.fs.dirname(vim.fs.find({ "gradlew", ".git", "mvnw" }, { upward = true })[1]),
}
local jdtls_group = vim.api.nvim_create_augroup("jdtls", { clear = true })
vim.api.nvim_create_autocmd("FileType", {
    pattern = { "java" },
    callback = function() require("jdtls").start_or_attach(config) end,
    group = jdtls_group,
})

-- Scala
local metals = require("metals")
local metals_config = metals.bare_config()
metals_config.capabilities = capabilities
metals_config.settings.useGlobalExecutable = true

require("dap").configurations.scala = {
    {
        type = "scala",
        request = "launch",
        name = "RunOrTest",
        metals = { runType = "runOrTestFile" },
    },
    {
        type = "scala",
        request = "launch",
        name = "Test Target",
        metals = { runType = "testTarget" },
    },
}

metals_config.on_attach = function(client, bufnr)
    metals.setup_dap()

    map("n", "<leader>ws", metals.hover_worksheet)

    map("n", "<leader>dc", require("dap").continue)
    map("n", "<leader>dr", require("dap").repl.toggle)
    map("n", "<leader>dK", require("dap.ui.widgets").hover)
    map("n", "<leader>dt", require("dap").toggle_breakpoint)
    map("n", "<leader>dso", require("dap").step_over)
    map("n", "<leader>dsi", require("dap").step_into)
    map("n", "<leader>dl", require("dap").run_last)

    mylsp.on_attach(client, bufnr)
end
local nvim_metals_group = vim.api.nvim_create_augroup("nvim-metals", { clear = true })
vim.api.nvim_create_autocmd("FileType", {
    pattern = { "scala", "sbt" },
    callback = function() require("metals").initialize_or_attach(metals_config) end,
    group = nvim_metals_group,
})

-- Haskell
vim.g.haskell_tools = {
    tools = {
        log = { level = vim.log.levels.OFF },
        hover = {
            border = border,
            stylize_markdown = true,
        },
    },
    hls = {
        on_attach = function(client, bufnr)
            local ht = require("haskell-tools")
            local opts = { buffer = bufnr }

            map("n", "<leader>hhe", ht.lsp.buf_eval_all, opts)
            map("n", "<leader>hhs", ht.hoogle.hoogle_signature, opts)
            map("n", "<leader>hhr", ht.repl.toggle, opts)

            vim.opt_local.shiftwidth = 2
            mylsp.on_attach(client, bufnr)
        end,
        default_settings = {
            haskell = {
                checkProject = false, -- PERF: don't check the entire project on initial load
                formattingProvider = "fourmolu",
                plugin = {
                    rename = {
                        config = {
                            diff = true, -- (experimental) rename across modules
                        },
                    },
                },
            },
        },
        settings = function(project_root)
            local ht = require("haskell-tools")
            return ht.lsp.load_hls_settings(project_root, { settings_file_pattern = "hls.json" })
        end,
    },
}

----------
-- Rust --
----------
vim.g.rustaceanvim = {
    server = {
        on_attach = mylsp.on_attach,
        settings = {
            ["rust-analyzer"] = { files = { excludeDirs = { ".direnv/" } } },
        },
    },
    tools = {
        hover = {
            border = border,
            stylize_markdown = true,
        },
        log = { level = vim.log.levels.OFF },
    },
}