Intercept file open

1 files changed, 102 insertions, 10 deletions

diff --git a/lua/user/mods.lua b/lua/user/mods.lua
index e4b6b41..6420ed5 100644
--- a/lua/user/mods.lua
+++ b/lua/user/mods.lua
@@ -27,14 +27,14 @@ end
 --------------------------------------------------
 
 -- Format on save
-local augroup = vim.api.nvim_create_augroup('LspFormatting', {})
+local format_augroup = vim.api.nvim_create_augroup('LspFormatting', {})
 require('null-ls').setup({
   -- you can reuse a shared lspconfig on_attach callback here
   on_attach = function(client, bufnr)
     if client.supports_method('textDocument/formatting') then
-      vim.api.nvim_clear_autocmds({ group = augroup, buffer = bufnr })
+      vim.api.nvim_clear_autocmds({ group = format_augroup, buffer = bufnr })
       vim.api.nvim_create_autocmd('BufWritePre', {
-        group = augroup,
+        group = format_augroup,
         buffer = bufnr,
         callback = function()
           -- on 0.8, you should use vim.lsp.buf.format({ bufnr = bufnr }) instead
@@ -134,15 +134,9 @@ end
 -- Define a global function to retrieve LSP clients based on Neovim version
 function M.get_lsp_clients(bufnr)
   local mods = require('user.mods')
-  local expected_ver = '0.10.0'
+  --local expected_ver = '0.10.0'
   local nvim_ver = mods.get_nvim_version()
 
-  --if nvim_ver ~= expected_ver then
-  --  local msg = string.format("Unsupported nvim version: expect %s, but got %s instead!", expected_ver, nvim_ver)
-  --  vim.api.nvim_err_writeln(msg)
-  --  return
-  --end
-
   local version_major, version_minor = string.match(nvim_ver, '(%d+)%.(%d+)')
   version_major = tonumber(version_major)
   version_minor = tonumber(version_minor)
@@ -720,5 +714,103 @@ end
 
 --------------------------------------------------
 
+-- Intercept file open
+local augroup = vim.api.nvim_create_augroup('user-autocmds', { clear = true })
+local intercept_file_open = true
+vim.api.nvim_create_user_command('InterceptToggle', function()
+  intercept_file_open = not intercept_file_open
+  local intercept_state = '`Enabled`'
+  if not intercept_file_open then
+    intercept_state = '`Disabled`'
+  end
+  vim.notify('Intercept file open set to ' .. intercept_state, vim.log.levels.INFO, {
+    title = 'Intercept File Open',
+    ---@param win integer The window handle
+    on_open = function(win)
+      vim.api.nvim_buf_set_option(vim.api.nvim_win_get_buf(win), 'filetype', 'markdown')
+    end,
+  })
+end, { desc = 'Toggles intercepting BufNew to open files in custom programs' })
+
+-- NOTE: Add "BufReadPre" to the autocmd events to also intercept files given on the command line, e.g.
+-- `nvim myfile.txt`
+vim.api.nvim_create_autocmd({ 'BufNew' }, {
+  group = augroup,
+  callback = function(args)
+    ---@type string
+    local path = args.match
+    ---@type integer
+    local bufnr = args.buf
+
+    ---@type string? The file extension if detected
+    local extension = vim.fn.fnamemodify(path, ':e')
+    ---@type string? The filename if detected
+    local filename = vim.fn.fnamemodify(path, ':t')
+
+    ---Open a given file path in a given program and remove the buffer for the file.
+    ---@param buf integer The buffer handle for the opening buffer
+    ---@param fpath string The file path given to the program
+    ---@param fname string The file name used in notifications
+    ---@param prog string The program to execute against the file path
+    local function open_in_prog(buf, fpath, fname, prog)
+      vim.notify(string.format('Opening `%s` in `%s`', fname, prog), vim.log.levels.INFO, {
+        title = 'Open File in External Program',
+        ---@param win integer The window handle
+        on_open = function(win)
+          vim.api.nvim_buf_set_option(vim.api.nvim_win_get_buf(win), 'filetype', 'markdown')
+        end,
+      })
+      local mods = require('user.mods')
+      local nvim_ver = mods.get_nvim_version()
+
+      local version_major, version_minor = string.match(nvim_ver, '(%d+)%.(%d+)')
+      version_major = tonumber(version_major)
+      version_minor = tonumber(version_minor)
+
+      if version_major > 0 or (version_major == 0 and version_minor >= 10) then
+        vim.system({ prog, fpath }, { detach = true })
+      else
+        vim.fn.jobstart({ prog, fpath }, { detach = true })
+      end
+      vim.api.nvim_buf_delete(buf, { force = true })
+    end
+
+    local extension_callbacks = {
+      ['pdf'] = function(buf, fpath, fname)
+        open_in_prog(buf, fpath, fname, 'zathura')
+      end,
+      ['png'] = function(buf, fpath, fname)
+        open_in_prog(buf, fpath, fname, 'feh')
+      end,
+      ['jpg'] = 'png',
+      ['mp4'] = function(buf, fpath, fname)
+        open_in_prog(buf, fpath, fname, 'mpv')
+      end,
+      ['gif'] = 'mp4',
+    }
+
+    ---Get the extension callback for a given extension. Will do a recursive lookup if an extension callback is actually
+    ---of type string to get the correct extension
+    ---@param ext string A file extension. Example: `png`.
+    ---@return fun(bufnr: integer, path: string, filename: string?) extension_callback The extension callback to invoke, expects a buffer handle, file path, and filename.
+    local function extension_lookup(ext)
+      local callback = extension_callbacks[ext]
+      if type(callback) == 'string' then
+        callback = extension_lookup(callback)
+      end
+      return callback
+    end
+
+    if extension ~= nil and not extension:match('^%s*$') and intercept_file_open then
+      local callback = extension_lookup(extension)
+      if type(callback) == 'function' then
+        callback(bufnr, path, filename)
+      end
+    end
+  end,
+})
+
+--------------------------------------------------
+
 -- ...
 return M