nixos-config/home-manager/modules/neovim/plugins/conform.nix

{
  lib,
  pkgs,
  ...
}: {
  programs.nixvim = {
    extraConfigLuaPre =
      # lua
      ''
        local slow_format_filetypes = {}

        vim.api.nvim_create_user_command("FormatDisable", function(args)
           if args.bang then
            -- FormatDisable! will disable formatting just for this buffer
            vim.b.disable_autoformat = true
          else
            vim.g.disable_autoformat = true
          end
        end, {
          desc = "Disable autoformat-on-save",
          bang = true,
        })
        vim.api.nvim_create_user_command("FormatEnable", function()
          vim.b.disable_autoformat = false
          vim.g.disable_autoformat = false
        end, {
          desc = "Re-enable autoformat-on-save",
        })
        vim.api.nvim_create_user_command("FormatToggle", function(args)
          if args.bang then
            -- Toggle formatting for current buffer
            vim.b.disable_autoformat = not vim.b.disable_autoformat
          else
            -- Toggle formatting globally
            vim.g.disable_autoformat = not vim.g.disable_autoformat
          end
        end, {
          desc = "Toggle autoformat-on-save",
          bang = true,
        })
      '';

    plugins = {
      conform-nvim = {
        enable = true;
        settings = {
          format_on_save =
            # lua
            ''
              function(bufnr)
                if vim.g.disable_autoformat or vim.b[bufnr].disable_autoformat then
                  return
                end

                if slow_format_filetypes[vim.bo[bufnr].filetype] then
                  return
                end

                local function on_format(err)
                  if err and err:match("timeout$") then
                    slow_format_filetypes[vim.bo[bufnr].filetype] = true
                  end
                end

                return { timeout_ms = 200, lsp_fallback = true }, on_format
               end
            '';

          format_after_save =
            # lua
            ''
              function(bufnr)
                if vim.g.disable_autoformat or vim.b[bufnr].disable_autoformat then
                  return
                end

                if not slow_format_filetypes[vim.bo[bufnr].filetype] then
                  return
                end

                return { lsp_fallback = true }
              end
            '';
        };

        # NOTE:
        # Conform will run multiple formatters sequentially
        # [ "1" "2" "3"]
        # Use a sub-list to run only the first available formatter
        # [ ["1"] ["2"] ["3"] ]
        # Use the "*" filetype to run formatters on all filetypes.
        # Use the "_" filetype to run formatters on filetypes that don't
        # have other formatters configured.
        formattersByFt = {
          bash = [
            "shellcheck"
            "shellharden"
            "shfmt"
          ];
          bicep = ["bicep"];
          c = ["clang_format"];
          cmake = ["cmake-format"];
          cpp = ["clang_format"];
          cs = ["csharpier"];
          css = ["stylelint"];
          fish = ["fish_indent"];
          fsharp = ["fantomas"];
          haskell = ["ormolu"];
          javascript = [
            [
              "prettierd"
              "prettier"
            ]
          ];
          json = ["jq"];
          lua = ["stylua"];
          markdown = ["deno_fmt"];
          nix = ["nixfmt"];
          python = [
            "isort"
            "black"
          ];
          rust = ["rustfmt"];
          sh = [
            "shellcheck"
            "shellharden"
            "shfmt"
          ];
          sql = ["sqlfluff"];
          swift = ["swift_format"];
          terraform = ["terraform_fmt"];
          toml = ["taplo"];
          typescript = [
            [
              "prettierd"
              "prettier"
            ]
          ];
          xml = [
            "xmlformat"
            "xmllint"
          ];
          yaml = ["yamlfmt"];
          zig = ["zigfmt"];
          "_" = [
            "squeeze_blanks"
            "trim_whitespace"
            "trim_newlines"
          ];
        };

        formatters = {
          black = {
            command = lib.getExe pkgs.black;
          };
          bicep = {
            command = lib.getExe pkgs.bicep;
          };
          cmake-format = {
            command = lib.getExe pkgs.cmake-format;
          };
          csharpier = {
            command = lib.getExe pkgs.csharpier;
          };
          deno_fmt = {
            command = lib.getExe pkgs.deno;
          };
          isort = {
            command = lib.getExe pkgs.isort;
          };
          fantomas = {
            command = lib.getExe pkgs.fantomas;
          };
          ormolu = {
            command = lib.getExe pkgs.ormolu;
          };
          jq = {
            command = lib.getExe pkgs.jq;
          };
          nixfmt = {
            command = lib.getExe pkgs.nixfmt-rfc-style;
          };
          prettierd = {
            command = lib.getExe pkgs.prettierd;
          };
          rustfmt = {
            command = lib.getExe pkgs.rustfmt;
          };
          shellcheck = {
            command = lib.getExe pkgs.shellcheck;
          };
          shfmt = {
            command = lib.getExe pkgs.shfmt;
          };
          shellharden = {
            command = lib.getExe pkgs.shellharden;
          };
          sqlfluff = {
            command = lib.getExe pkgs.sqlfluff;
          };
          squeeze_blanks = {
            comamnd = lib.getExe' pkgs.coreutils "cat";
          };
          stylelint = {
            command = lib.getExe pkgs.stylelint;
          };
          stylua = {
            command = lib.getExe pkgs.stylua;
          };
          swift_format = {
            command = lib.getExe pkgs.swift-format;
          };
          taplo = {
            command = lib.getExe pkgs.taplo;
          };
          terraform_fmt = {
            command = lib.getExe pkgs.terraform;
          };
          xmlformat = {
            command = lib.getExe pkgs.xmlformat;
          };
          yamlfmt = {
            command = lib.getExe pkgs.yamlfmt;
          };
          zigfmt = {
            command = lib.getExe pkgs.zig;
          };
        };
      };
    };
  };
}