Automated update

nvim/lua/encrypted_file_handler.lua

@@ -0,0 +1,234 @@
+-- File: lua/encrypted_file_handler.lua
+local M = {}
+
+-- Default configuration; users can override these via setup()
+local config = {
+  -- Patterns for encrypted files (Lua patterns, so escape the dot)
+  file_patterns = { "%.pgp$", "%.gpg$", "%.enc$", "%.aes$", "%.kdbx$", "%.vault$" },
+  -- Passphrase prompt method: "vim_ui", "dmenu", or "terminal"
+  prompt_method = "vim_ui",
+  -- Custom decryption methods by extension; leave empty to use builtins
+  -- e.g., config.decryption_methods["kdbx"] = function(pass, orig, tmp) ... end
+  decryption_methods = {},
+  -- Automatically delete decrypted temp file when buffer is closed
+  auto_cleanup = true,
+  -- Optional timeout (in seconds) to auto-delete decrypted file (0 = disabled)
+  cleanup_timeout = 0,
+  -- Debug flag (prints extra info)
+  debug = false,
+}
+
+-- Merge user config with defaults
+function M.setup(user_config)
+  config = vim.tbl_extend("force", config, user_config or {})
+  if config.debug then
+    print("Encrypted file handler loaded with config:")
+    print(vim.inspect(config))
+  end
+  M.setup_autocmds()
+end
+
+-- Check if the filename matches any encrypted file pattern
+local function is_encrypted_file(filename)
+  for _, pattern in ipairs(config.file_patterns) do
+    if filename:match(pattern) then
+      return true
+    end
+  end
+  return false
+end
+
+-- Prompt the user for a passphrase via different methods.
+-- The callback is called with the entered passphrase.
+local function prompt_passphrase(callback)
+  if config.prompt_method == "vim_ui" then
+    vim.ui.input({ prompt = "Enter decryption passphrase: ", secret = true }, function(input)
+      callback(input)
+    end)
+  elseif config.prompt_method == "dmenu" then
+    -- dmenu: call it synchronously via io.popen
+    local handle = io.popen("dmenu -p 'Enter decryption passphrase:'")
+    local result = handle:read("*a") or ""
+    handle:close()
+    result = result:gsub("\n", "") -- trim newline
+    callback(result)
+  elseif config.prompt_method == "terminal" then
+    -- Terminal: create a temporary floating window to ask for input.
+    local bufnr = vim.api.nvim_create_buf(false, true)
+    local width = 50
+    local height = 1
+    local opts = {
+      relative = "editor",
+      width = width,
+      height = height,
+      row = (vim.o.lines - height) / 2,
+      col = (vim.o.columns - width) / 2,
+      border = "single",
+    }
+    local win = vim.api.nvim_open_win(bufnr, true, opts)
+    vim.api.nvim_buf_set_lines(bufnr, 0, -1, false, { "Enter decryption passphrase:" })
+    -- Fallback: use vim.fn.input for capturing input (note: this does not hide the input)
+    local result = vim.fn.input("Passphrase: ")
+    vim.api.nvim_buf_delete(bufnr, { force = true })
+    callback(result)
+  else
+    -- Default fallback: vim.ui.input
+    vim.ui.input({ prompt = "Enter decryption passphrase: ", secret = true }, function(input)
+      callback(input)
+    end)
+  end
+end
+
+-- Built-in decryption command generators
+local builtin_methods = {
+  pgp = function(pass, orig, tmp)
+    -- GPG: passphrase is fed via stdin using --passphrase-fd 0
+    return string.format("gpg --batch --yes --passphrase-fd 0 --output %s --decrypt %s", 
+      vim.fn.shellescape(tmp), vim.fn.shellescape(orig))
+  end,
+  gpg = function(pass, orig, tmp)
+    return string.format("gpg --batch --yes --passphrase-fd 0 --output %s --decrypt %s", 
+      vim.fn.shellescape(tmp), vim.fn.shellescape(orig))
+  end,
+  enc = function(pass, orig, tmp)
+    -- OpenSSL: passphrase is provided inline (note: this exposes it in the process list)
+    return string.format("openssl enc -aes-256-cbc -d -in %s -out %s -pass pass:%s", 
+      vim.fn.shellescape(orig), vim.fn.shellescape(tmp), vim.fn.shellescape(pass))
+  end,
+  aes = function(pass, orig, tmp)
+    return string.format("openssl enc -aes-256-cbc -d -in %s -out %s -pass pass:%s", 
+      vim.fn.shellescape(orig), vim.fn.shellescape(tmp), vim.fn.shellescape(pass))
+  end,
+}
+
+-- Determines which decryption command to use based on the file extension.
+-- Returns the command string or nil plus an error message.
+local function get_decryption_command(ext, pass, orig, tmp)
+  ext = ext:lower()
+  local method = nil
+  if ext == "pgp" or ext == "gpg" then
+    method = config.decryption_methods[ext] or builtin_methods.gpg
+  elseif ext == "enc" or ext == "aes" then
+    method = config.decryption_methods[ext] or builtin_methods.enc
+  else
+    -- For custom types (e.g. kdbx, vault), require a user-supplied method.
+    method = config.decryption_methods[ext]
+    if not method then
+      return nil, "No decryption method defined for extension: " .. ext
+    end
+  end
+  if type(method) == "function" then
+    return method(pass, orig, tmp)
+  elseif type(method) == "string" then
+    return string.format(method, vim.fn.shellescape(tmp), vim.fn.shellescape(orig), vim.fn.shellescape(pass))
+  else
+    return nil, "Invalid decryption method configuration for extension: " .. ext
+  end
+end
+
+-- Decrypts the file and opens the decrypted content in a new, secure buffer.
+function M.decrypt_and_open(original_file)
+  local ext = original_file:match("^.+%.([^.]+)$")
+  if not ext then
+    print("Unable to determine file extension for decryption.")
+    return
+  end
+
+  prompt_passphrase(function(passphrase)
+    if not passphrase or passphrase == "" then
+      print("Decryption cancelled: No passphrase provided.")
+      return
+    end
+
+    local tmp_file = vim.fn.tempname() -- temporary file path
+    local cmd, err = get_decryption_command(ext, passphrase, original_file, tmp_file)
+    if not cmd then
+      print("Decryption error: " .. err)
+      return
+    end
+
+    if config.debug then
+      print("Running decryption command: " .. cmd)
+    end
+
+    -- For GPG, we need to feed the passphrase via stdin.
+    local stdin = (ext == "pgp" or ext == "gpg") and passphrase or nil
+    local output = vim.fn.system(cmd, stdin)
+    local exit_code = vim.v.shell_error
+    if exit_code ~= 0 then
+      print("Decryption failed. Please check your passphrase and method.")
+      if config.debug then
+        print("Command output: " .. output)
+      end
+      return
+    end
+
+    -- Open the decrypted file in a new buffer
+    vim.cmd("edit " .. vim.fn.fnameescape(tmp_file))
+    local bufnr = vim.api.nvim_get_current_buf()
+    -- Set buffer options: nofile, no swapfile, readonly
+    vim.bo[bufnr].buftype = "nofile"
+    vim.bo[bufnr].swapfile = false
+    vim.bo[bufnr].readonly = true
+
+    -- Store the original encrypted file and temp file paths in buffer variables
+    vim.api.nvim_buf_set_var(bufnr, "original_encrypted_file", original_file)
+    vim.api.nvim_buf_set_var(bufnr, "decrypted_temp_file", tmp_file)
+
+    -- Setup automatic cleanup when the buffer is unloaded or wiped out
+    if config.auto_cleanup then
+      vim.api.nvim_create_autocmd({ "BufUnload", "BufWipeout" }, {
+        buffer = bufnr,
+        callback = function()
+          if vim.loop.fs_stat(tmp_file) then
+            os.remove(tmp_file)
+            if config.debug then
+              print("Cleaned up temporary decrypted file: " .. tmp_file)
+            end
+          end
+        end,
+      })
+      -- Optionally, add a timer to auto-delete the file after a set timeout
+      if config.cleanup_timeout and config.cleanup_timeout > 0 then
+        vim.defer_fn(function()
+          if vim.loop.fs_stat(tmp_file) then
+            os.remove(tmp_file)
+            if config.debug then
+              print("Auto-cleanup: Deleted temporary decrypted file after timeout: " .. tmp_file)
+            end
+          end
+        end, config.cleanup_timeout * 1000)
+      end
+    end
+  end)
+end
+
+-- Autocommand callback: if the file being opened matches an encrypted pattern,
+-- schedule decryption.
+local function on_buf_read_pre(args)
+  local filename = args.file
+  if filename and is_encrypted_file(filename) then
+    vim.schedule(function()
+      M.decrypt_and_open(filename)
+    end)
+  end
+end
+
+-- Setup autocommands to hook into BufReadPre and BufNewFile events.
+function M.setup_autocmds()
+  vim.api.nvim_create_autocmd({ "BufReadPre", "BufNewFile" }, {
+    callback = on_buf_read_pre,
+  })
+end
+
+-- Expose a user command to manually trigger decryption.
+vim.api.nvim_create_user_command("DecryptFile", function(opts)
+  local file = opts.args
+  if file == "" then
+    file = vim.fn.expand("%:p")
+  end
+  M.decrypt_and_open(file)
+end, { nargs = "?" })
+
+return M
+