nvim: Stay centered in zen mode

By default we always stay centered in zen mode, like using a typewriter.
The old zen mode can still be reached with `[sZ` (capital Z).

nvim/.config/nvim/lazy-lock.json

@@ -86,6 +86,7 @@
   "rainbow-delimiters.nvim": { "branch": "master", "commit": "1ab18259472d9fe5756750fec722c31bab1712da" },
   "render-markdown.nvim": { "branch": "main", "commit": "6d03af10063d5a2fadec3559de5dfa68da7d00ef" },
   "smartcolumn.nvim": { "branch": "main", "commit": "d01b99355c7fab13233f48d0f28dc097e68a03f7" },
+  "stay-centered.nvim": { "branch": "main", "commit": "e1a63ccaf2584e97c0ef8e64f9654c9a80d983f6" },
   "stickybuf.nvim": { "branch": "master", "commit": "2160fcd536d81f5fa43f7167dba6634e814e3154" },
   "texpresso.vim": { "branch": "main", "commit": "907838c08bbf99ad6bed3c908f1d0551a92ab4e0" },
   "todo-comments.nvim": { "branch": "main", "commit": "ae0a2afb47cf7395dc400e5dc4e05274bf4fb9e0" },

nvim/.config/nvim/lua/plugins/base.lua

@@ -210,8 +210,45 @@ return {
 		"echasnovski/mini.nvim",
 		event = { "InsertEnter", "VeryLazy" },
 		config = function()
-			-- manually create lazy loading scenarios
-			require("mini.ai").setup()
+			local ai = require("mini.ai")
+			local function ai_buffer(ai_type)
+				local start_line, end_line = 1, vim.fn.line("$")
+				if ai_type == "i" then
+					-- Skip first and last blank lines for `i` textobject
+					local first_nonblank, last_nonblank = vim.fn.nextnonblank(start_line), vim.fn.prevnonblank(end_line)
+					-- Do nothing for buffer with all blanks
+					if first_nonblank == 0 or last_nonblank == 0 then
+						return { from = { line = start_line, col = 1 } }
+					end
+					start_line, end_line = first_nonblank, last_nonblank
+				end
+
+				local to_col = math.max(vim.fn.getline(end_line):len(), 1)
+				return { from = { line = start_line, col = 1 }, to = { line = end_line, col = to_col } }
+			end
+			ai.setup({
+				custom_textobjects = {
+					c = ai.gen_spec.treesitter({ a = "@class.outer", i = "@class.inner" }), -- class
+					d = { "%f[%d]%d+" }, -- digits
+					e = { -- single part of MultiCaseWords
+						{
+							"%u[%l%d]+%f[^%l%d]",
+							"%f[%S][%l%d]+%f[^%l%d]",
+							"%f[%P][%l%d]+%f[^%l%d]",
+							"^[%l%d]+%f[^%l%d]",
+						},
+						"^().*()$",
+					},
+					f = ai.gen_spec.treesitter({ a = "@function.outer", i = "@function.inner" }), -- function
+					g = ai_buffer, -- buffer with or without whitespace
+					o = ai.gen_spec.treesitter({ -- current 'codeblock'
+						a = { "@block.outer", "@conditional.outer", "@loop.outer" },
+						i = { "@block.inner", "@conditional.inner", "@loop.inner" },
+					}),
+					u = ai.gen_spec.function_call(), -- function [u]sage
+					U = ai.gen_spec.function_call({ name_pattern = "[%w_]" }), -- function [U]sage of last dot element
+				},
+			})
 			-- Align tables and other alignable things
 			require("mini.align").setup({})
 

nvim/.config/nvim/lua/plugins/prose.lua

@@ -33,10 +33,28 @@ local prose_plugs = {
 		"folke/zen-mode.nvim",
 		config = true,
 		cmd = { "ZenMode" },
-		dependencies = { "folke/twilight.nvim" },
+		dependencies = { "folke/twilight.nvim", { "arnamak/stay-centered.nvim", opts = { enabled = false } } },
 		keys = {
 			{
 				"[sz",
+				function()
+					require("zen-mode").close()
+					require("stay-centered").disable()
+				end,
+				silent = true,
+				desc = "stop center zen mode",
+			},
+			{
+				"]sz",
+				function()
+					require("zen-mode").open()
+					require("stay-centered").enable()
+				end,
+				silent = true,
+				desc = "start center zen mode",
+			},
+			{
+				"[sZ",
 				function()
 					require("zen-mode").close()
 				end,
@@ -44,7 +62,7 @@ local prose_plugs = {
 				desc = "stop zen mode",
 			},
 			{
-				"]sz",
+				"]sZ",
 				function()
 					require("zen-mode").open()
 				end,