viye @ 99e30d03dbda8110ba0f2d9bbc2f40ac733fb53d

local function indent(t) return #t:match("^%s*") end

local function line_type(line)

  if not line:find("%S") then return "empty" end

  return line:find("^%s*[|:]") and "data" or "node"

end

local function children_of(cmd_lnum)

  local depth = indent(vim.fn.getline(cmd_lnum))

  local first, last = cmd_lnum + 1, nil

  for i = first, vim.fn.line("$") do

    local l = vim.fn.getline(i)

    if l == "" or indent(l) <= depth then break end

    last = i

  end

  return first, last

end

local function parent_of(lnum)

  local d = indent(vim.fn.getline(lnum))

  for i = lnum - 1, 1, -1 do

    local l = vim.fn.getline(i)

    if line_type(l) == "node" and indent(l) < d then return i end

  end

  return nil

end

local function ancestors(cmd_lnum)

  local parts = {}

  local lnum = cmd_lnum

  while lnum do

    local l = vim.fn.getline(lnum)

    table.insert(parts, 1, l:match("^%s*[+-] (.*)") or vim.trim(l))

    lnum = parent_of(lnum)

  end

  return parts

end

local function body_of(cmd_lnum)

  local depth = indent(vim.fn.getline(cmd_lnum))

  local first, last = children_of(cmd_lnum)

  local body = {}

  if last then

    for i = first, last do

      local l = vim.fn.getline(i)

      local val = indent(l) == depth + 2 and l:match("^%s*: (.*)")

      if val then table.insert(body, ": " .. val) end

    end

  end

  return body

end

local function run(cmd_lnum)

  local cmd = ancestors(cmd_lnum)

  if #cmd == 0 then return end

  table.insert(cmd, 1, "viye")

  local body = body_of(cmd_lnum)

  if #body > 0 then vim.list_extend(vim.list_extend(cmd, { "--" }), body) end

  local res = vim.system(cmd, { text = true }):wait(2000)

  if res.code ~= 0 then

    vim.notify(vim.trim(res.stderr), vim.log.levels.ERROR)

    return

  end

  return res.stdout

end

local function insert_output(cmd_lnum, out)

  local pad = string.rep(" ", indent(vim.fn.getline(cmd_lnum)) + 2)

  local lines = vim.split(out, "\n", { trimempty = true })

  for i, l in ipairs(lines) do

    lines[i] = pad .. l

  end

  vim.fn.append(cmd_lnum, lines)

end

local function toggle_bullet(cmd_lnum)

  vim.fn.setline(cmd_lnum, (vim.fn.getline(cmd_lnum):gsub("^[+-] ", function(c)

    return c == "+" and "-" or "+"

  end, 1)))

end

local function exec()

  local lnum = vim.fn.line(".")

  local line = vim.fn.getline(lnum)

  local cmd_lnum = line_type(line) == "data" and parent_of(lnum) or lnum

  if not cmd_lnum then return end

  local first, last = children_of(cmd_lnum)

  local has_children = last ~= nil

  local on_cmd = cmd_lnum == lnum

  if has_children and (on_cmd or line_type(line) == "data") then

    if last then vim.cmd(string.format("%d,%ddelete _", first, last)) end

    toggle_bullet(cmd_lnum)

    return

  end

  local out = run(cmd_lnum)

  if not out then return end

  if last then vim.cmd(string.format("%d,%ddelete _", first, last)) end

  if out ~= "" then insert_output(cmd_lnum, out) end

  toggle_bullet(cmd_lnum)

end

vim.filetype.add { extension = { viye = "viye" } }

local group = vim.api.nvim_create_augroup("viye", { clear = true })

vim.api.nvim_create_autocmd("BufEnter", {

  pattern = "*",

  group = group,

  callback = function()

    if vim.api.nvim_buf_get_name(0) == "" then

      vim.bo.filetype = "viye"

    end

  end,

})

vim.api.nvim_create_autocmd("FileType", {

  pattern = "viye",

  group = group,

  callback = function()

    vim.keymap.set("n", "<CR>", exec, { buffer = true, silent = true })

  end,

})