Neovim Filelinks Plugin

filelinks.lua

-- Drop this in /after or /after/plugin/
-- explanation at commands (at end of file)

vim.g.exo = "where you store your data files"
local filelinks_file = vim.g.exo .. 'filelinks.json'

local function get_filelinks()
  return vim.fn.json_decode(vim.fn.readfile(filelinks_file))
end

local function get_links_for_file(file)
  local filelinks = get_filelinks()
  return filelinks[string.lower(file)]
end

local function add_link_for_file(linkpath)
  vim.opt.shellslash = true -- to make windows play nice
  linkpath = string.lower(vim.fs.joinpath(linkpath)) -- normalizes path
  local filelinks = get_filelinks()
  local file = string.lower(vim.fn.expand('%:p'))
  -- todo:: normalize the 
  if filelinks[file] then
    table.insert(filelinks[file], linkpath)
  else
    filelinks[file] = { linkpath }
  end

  -- Avoid clobbering the file if invalid
  local s = vim.fn.json_encode(filelinks)
  if s then
    vim.fn.writefile({s}, filelinks_file)
  end
  vim.opt.shellslash = false
end

local function delete_link(file)
  vim.opt.shellslash = true -- to make windows play nice
  file = string.lower(vim.fs.joinpath(file))
  local filelinks = get_filelinks()
  local links = get_links_for_file(file)
  local to_del
  vim.ui.select(
    links, {prompt="Delete a link" }, 
    function(_, choice) to_del = choice
    end
  )

  if to_del then
    table.remove(filelinks[file], to_del)

    -- Avoid clobbering the file if invalid
    local s = vim.fn.json_encode(filelinks)
    if s then
      vim.fn.writefile({s}, filelinks_file)
    end
  end
  vim.opt.shellslash = false
end

local function goto_link(file)
  file = string.lower(vim.fs.joinpath(file))
  local links = get_links_for_file(file)
  local target
  if vim.tbl_count(links) == 1 then --only one link
    target = links[1]
  else
    vim.ui.select(
      links, {prompt="",
      }, function(choice) target = choice end
    )
  end
  if target then
    vim.cmd.edit(vim.fs.joinpath(target))  -- joinpath normalizes
  end
end

-- save another buffer as a link for this file
vim.api.nvim_create_user_command('Fladd', function(opts) add_link_for_file(opts.fargs[1]) end, {nargs=1, complete='buffer'})

-- jump to any linked file
vim.api.nvim_create_user_command('Fl', function(opts) goto_link(vim.fn.expand('%:p')) end, {})

-- remove a link you hate
vim.api.nvim_create_user_command('Fldel', function(opts) delete_link(vim.fn.expand('%:p')) end, {})