neovim-flake/modules/lsp/config.nix

{
  pkgs,
  config,
  lib,
  ...
}:
with lib;
with builtins; let
  cfg = config.vim.lsp;
in {
  options.vim.lsp = {
    enable = mkEnableOption "neovim lsp support";
    formatOnSave = mkEnableOption "Format on save";
    nix = {
      enable = mkEnableOption "Nix LSP";
      server = mkOption {
        type = with types; enum ["rnix" "nil"];
        default = "nil";
        description = "Which LSP to use";
      };

      pkg = mkOption {
        type = types.package;
        default =
          if (cfg.nix.server == "rnix")
          then pkgs.rnix-lsp
          else pkgs.nil;
        description = "The LSP package to use";
      };

      formatter = mkOption {
        type = with types; enum ["nixpkgs-fmt" "alejandra"];
        default = "alejandra";
        description = "Which nix formatter to use";
      };
    };
    rust = {
      enable = mkEnableOption "Rust LSP";
      rustAnalyzerOpts = mkOption {
        type = types.str;
        default = ''
          ["rust-analyzer"] = {
            experimental = {
              procAttrMacros = true,
            },
          },
        '';
        description = "options to pass to rust analyzer";
      };
    };
    python = mkEnableOption "Python LSP";
    clang = {
      enable = mkEnableOption "C language LSP";
      c_header = mkEnableOption "C syntax header files";
      cclsOpts = mkOption {
        type = types.str;
        default = "";
      };
    };
    sql = mkEnableOption "SQL Language LSP";
    go = mkEnableOption "Go language LSP";
    ts = mkEnableOption "TS language LSP";
    zig.enable = mkEnableOption "Zig language LSP";
  };

  config = mkIf cfg.enable (
    let
      writeIf = cond: msg:
        if cond
        then msg
        else "";
    in {
      vim.startPlugins =
        [
          "nvim-lspconfig"
          "null-ls"
          (
            if (config.vim.autocomplete.enable && (config.vim.autocomplete.type == "nvim-cmp"))
            then "cmp-nvim-lsp"
            else null
          )
          (
            if cfg.sql
            then "sqls-nvim"
            else null
          )
        ]
        ++ (
          if cfg.rust.enable
          then [
            "crates-nvim"
            "rust-tools"
          ]
          else []
        );

      vim.configRC.lsp = nvim.dag.entryAnywhere ''
        ${
          if cfg.nix.enable
          then ''
            autocmd filetype nix setlocal tabstop=2 shiftwidth=2 softtabstop=2
          ''
          else ""
        }

        ${
          if cfg.clang.c_header
          then ''
            " c syntax for header (otherwise breaks treesitter highlighting)
            " https://www.reddit.com/r/neovim/comments/orfpcd/question_does_the_c_parser_from_nvimtreesitter/
            let g:c_syntax_for_h = 1
          ''
          else ""
        }
      '';
      vim.luaConfigRC.lsp = nvim.dag.entryAnywhere ''

        local attach_keymaps = function(client, bufnr)
          local opts = { noremap=true, silent=true }

          vim.api.nvim_buf_set_keymap(bufnr, 'n', '<leader>lgD', '<cmd>lua vim.lsp.buf.declaration()<CR>', opts)
          vim.api.nvim_buf_set_keymap(bufnr, 'n', '<leader>lgd', '<cmd>lua vim.lsp.buf.definition()<CR>', opts)
          vim.api.nvim_buf_set_keymap(bufnr, 'n', '<leader>lgt', '<cmd>lua vim.lsp.buf.type_definition()<CR>', opts)
          vim.api.nvim_buf_set_keymap(bufnr, 'n', '<leader>lgn', '<cmd>lua vim.diagnostic.goto_next()<CR>', opts)
          vim.api.nvim_buf_set_keymap(bufnr, 'n', '<leader>lgp', '<cmd>lua vim.diagnostic.goto_prev()<CR>', opts)

          vim.api.nvim_buf_set_keymap(bufnr, 'n', '<leader>lwa', '<cmd>lua vim.lsp.buf.add_workspace_folder()<CR>', opts)
          vim.api.nvim_buf_set_keymap(bufnr, 'n', '<leader>lwr', '<cmd>lua vim.lsp.buf.remove_workspace_folder()<CR>', opts)
          vim.api.nvim_buf_set_keymap(bufnr, 'n', '<leader>lwl', '<cmd>lua print(vim.inspect(vim.lsp.buf.list_workspace_folders()))<CR>', opts)

          vim.api.nvim_buf_set_keymap(bufnr, 'n', '<leader>lh', '<cmd>lua vim.lsp.buf.hover()<CR>', opts)
          vim.api.nvim_buf_set_keymap(bufnr, 'n', '<leader>ls', '<cmd>lua vim.lsp.buf.signature_help()<CR>', opts)
          vim.api.nvim_buf_set_keymap(bufnr, 'n', '<leader>ln', '<cmd>lua vim.lsp.buf.rename()<CR>', opts)
        end

        local null_ls = require("null-ls")
        local null_helpers = require("null-ls.helpers")
        local null_methods = require("null-ls.methods")

        local ls_sources = {
          ${writeIf cfg.python
          ''
            null_ls.builtins.formatting.black.with({
              command = "${pkgs.black}/bin/black",
            }),
          ''}

          -- Commented out for now
          --${writeIf (config.vim.git.enable && config.vim.git.gitsigns.enable) ''
          --  null_ls.builtins.code_actions.gitsigns,
          --''}

          ${writeIf cfg.sql
          ''
            null_helpers.make_builtin({
              method = null_methods.internal.FORMATTING,
              filetypes = { "sql" },
              generator_opts = {
                to_stdin = true,
                ignore_stderr = true,
                suppress_errors = true,
                command = "${pkgs.sqlfluff}/bin/sqlfluff",
                args = {
                  "fix",
                  "-",
                },
              },
              factory = null_helpers.formatter_factory,
            }),

            null_ls.builtins.diagnostics.sqlfluff.with({
              command = "${pkgs.sqlfluff}/bin/sqlfluff",
              extra_args = {"--dialect", "postgres"}
            }),
          ''}

          ${writeIf
          (cfg.nix.enable
            && cfg.nix.server == "rnix"
            && cfg.nix.formatter == "alejandra")
          ''
            null_ls.builtins.formatting.alejandra.with({
              command = "${pkgs.alejandra}/bin/alejandra"
            }),
          ''}

          ${writeIf cfg.ts
          ''
            null_ls.builtins.diagnostics.eslint,
            null_ls.builtins.formatting.prettier,
          ''}
        }

        vim.g.formatsave = ${
          if cfg.formatOnSave
          then "true"
          else "false"
        };

        -- Enable formatting
        format_callback = function(client, bufnr)
          vim.api.nvim_create_autocmd("BufWritePre", {
            group = augroup,
            buffer = bufnr,
            callback = function()
              if vim.g.formatsave then
                if client.supports_method("textDocument/formatting") then
                  local params = require'vim.lsp.util'.make_formatting_params({})
                  client.request('textDocument/formatting', params, nil, bufnr)
                end
              end
            end
          })
        end

        default_on_attach = function(client, bufnr)
          attach_keymaps(client, bufnr)
          format_callback(client, bufnr)
        end

        -- Enable null-ls
        require('null-ls').setup({
          diagnostics_format = "[#{m}] #{s} (#{c})",
          debounce = 250,
          default_timeout = 5000,
          sources = ls_sources,
          on_attach=default_on_attach
        })

        -- Enable lspconfig
        local lspconfig = require('lspconfig')

        local capabilities = vim.lsp.protocol.make_client_capabilities()
        ${
          let
            cfg = config.vim.autocomplete;
          in
            writeIf cfg.enable (
              if cfg.type == "nvim-cmp"
              then ''
                capabilities = require('cmp_nvim_lsp').default_capabilities()
              ''
              else ""
            )
        }

        ${writeIf cfg.rust.enable ''
          -- Rust config
          local rt = require('rust-tools')

          rust_on_attach = function(client, bufnr)
            default_on_attach(client, bufnr)
            local opts = { noremap=true, silent=true, buffer = bufnr }
            vim.keymap.set("n", "<leader>ris", rt.inlay_hints.set, opts)
            vim.keymap.set("n", "<leader>riu", rt.inlay_hints.unset, opts)
            vim.keymap.set("n", "<leader>rr", rt.runnables.runnables, opts)
            vim.keymap.set("n", "<leader>rp", rt.parent_module.parent_module, opts)
            vim.keymap.set("n", "<leader>rm", rt.expand_macro.expand_macro, opts)
            vim.keymap.set("n", "<leader>rc", rt.open_cargo_toml.open_cargo_toml, opts)
            vim.keymap.set("n", "<leader>rg", function() rt.crate_graph.view_crate_graph("x11", nil) end, opts)
          end

          local rustopts = {
            tools = {
              autoSetHints = true,
              hover_with_actions = false,
              inlay_hints = {
                only_current_line = false,
              }
            },
            server = {
              capabilities = capabilities,
              on_attach = rust_on_attach,
              cmd = {"${pkgs.rust-analyzer}/bin/rust-analyzer"},
              settings = {
                ${cfg.rust.rustAnalyzerOpts}
              }
            }
          }

          require('crates').setup {
            null_ls = {
              enabled = true,
              name = "crates.nvim",
            }
          }
          rt.setup(rustopts)
        ''}

        ${optionalString cfg.zig.enable ''
          -- Zig config
          lspconfig.zls.setup {
            capabilities = capabilities,
            on_attach=default_on_attach,
            cmd = {"${pkgs.zls}/bin/zls"},
            settings = {
              ["zls"] = {
                zig_exe_path = "${pkgs.zig}/bin/zig",
                zig_lib_path = "${pkgs.zig}/lib/zig",
              }
            }
          }
        ''}

        ${writeIf cfg.python ''
          -- Python config
          lspconfig.pyright.setup{
            capabilities = capabilities;
            on_attach=default_on_attach;
            cmd = {"${pkgs.nodePackages.pyright}/bin/pyright-langserver", "--stdio"}
          }
        ''}

        ${writeIf cfg.nix.enable (
          (writeIf (cfg.nix.server == "rnix") ''
            -- Nix (rnix) config
            lspconfig.rnix.setup{
              capabilities = capabilities,
              ${writeIf (cfg.nix.formatter == "alejandra")
              ''
                on_attach = function(client, bufnr)
                  attach_keymaps(client, bufnr)
                end,
              ''}
              ${writeIf (cfg.nix.formatter == "nixpkgs-fmt")
              ''
                on_attach = default_on_attach,
              ''}
              cmd = {"${cfg.nix.pkg}/bin/rnix-lsp"},
            }
          '')
          + (writeIf (cfg.nix.server == "nil") ''
            -- Nix (nil) config
            lspconfig.nil_ls.setup{
              capabilities = capabilities,
              on_attach=default_on_attach,
              cmd = {"${cfg.nix.pkg}/bin/nil"},
              settings = {
                ["nil"] = {
              ${writeIf (cfg.nix.formatter == "alejandra")
              ''
                formatting = {
                  command = {"${pkgs.alejandra}/bin/alejandra", "--quiet"},
                },
              ''}
              ${writeIf (cfg.nix.formatter == "nixpkgs-fmt")
              ''
                formatting = {
                  command = {"${pkgs.nixpkgs-fmt}/bin/nixpkgs-fmt"},
                },
              ''}
                },
              };
            }
          '')
        )}


        ${writeIf cfg.clang.enable ''
          -- CCLS (clang) config
          lspconfig.ccls.setup{
            capabilities = capabilities;
            on_attach=default_on_attach;
            cmd = {"${pkgs.ccls}/bin/ccls"};
            ${
            if cfg.clang.cclsOpts == ""
            then ""
            else "init_options = ${cfg.clang.cclsOpts}"
          }
          }
        ''}

        ${writeIf cfg.sql ''
          -- SQLS config
          lspconfig.sqls.setup {
            on_attach = function(client)
              client.server_capabilities.execute_command = true
              on_attach_keymaps(client, bufnr)
              require'sqls'.setup{}
            end,
            cmd = {"${pkgs.sqls}/bin/sqls", "-config", string.format("%s/config.yml", vim.fn.getcwd()) }
          }
        ''}

        ${writeIf cfg.go ''
          -- Go config
          lspconfig.gopls.setup {
            capabilities = capabilities;
            on_attach = default_on_attach;
            cmd = {"${pkgs.gopls}/bin/gopls", "serve"},
          }
        ''}

        ${writeIf cfg.ts ''
          -- TS config
          lspconfig.tsserver.setup {
            capabilities = capabilities;
            on_attach = function(client, bufnr)
              attach_keymaps(client, bufnr)
            end,
            cmd = { "${pkgs.nodePackages.typescript-language-server}/bin/typescript-language-server", "--stdio" }
          }
        ''}
      '';
    }
  );
}