local ls = require('luasnip')
local types = require('luasnip.util.types')

vim.api.nvim_set_hl(0, 'LuasnipIndicator', {
  fg = vim.g.terminal_color_15,
  bg = vim.g.terminal_color_1,
  italic = true,
  nocombine = true,
})

-- autowrap: wraps the function in top and bot if there is any content
local autowrap = function(top, bot, inner)
  local autoinsert = function(args, _, _, wrap_with)
    local nodes = {}
    if vim.trim(table.concat(args[1] or {})) ~= '' then
      table.insert(nodes, wrap_with)
    end
    return ls.sn(nil, nodes)
  end

  local argnodes = {}
  local maxpos = -1
  for _, e in ipairs(inner) do
    if e.pos ~= nil then
      table.insert(argnodes, e.pos)
      if e.pos > maxpos then
        maxpos = e.pos
      end
    end
  end

  local nodes = {}
  table.insert(nodes, ls.d(maxpos + 1, autoinsert, argnodes, { user_args = { top } }))
  for _, e in ipairs(inner) do
    table.insert(nodes, e)
  end
  table.insert(nodes, ls.d(maxpos + 2, autoinsert, argnodes, { user_args = { bot } }))
  return nodes
end

-- comment: wraps the content in &commentstring (or a blockcomment)
local comment = function(wrapped, blockcomment)
  -- commentstring helper
  local get_cstring = function()
    local cs = require('Comment.ft').calculate({
      ctype = blockcomment and 2 or 1,
      range = require('Comment.utils').get_region(),
    })
    local tbl = vim.split(cs or '', '%s', { plain = true, trimempty = true })
    return (#tbl == 0) and { '', '' }
      or ((#tbl == 1) and { tbl[1] .. ' ', '' } or { tbl[1], tbl[2] })
  end

  if type(wrapped) ~= 'table' then
    wrapped = { wrapped }
  end

  local nodes = {}
  table.insert(
    nodes,
    ls.f(function()
      return get_cstring()[1]
    end)
  )
  for _, n in ipairs(wrapped) do
    table.insert(nodes, n)
  end
  table.insert(
    nodes,
    ls.f(function()
      return get_cstring()[2]
    end)
  )
  return nodes
end

-- exec: inserts the output of command
local exec = function(command)
  return ls.f(function(_, _, ...)
    local results, code = require('plenary.job')
      :new({
        command = vim.env.SHELL,
        args = { '-c', ... },
        enable_recording = true,
      })
      :sync()
    if not code == 0 or #results == 0 then
      error(string.format('exec "%s" failed', ...))
    end
    return results
  end, {}, { user_args = { command } })
end

local file_contents = function(path, vargs)
  return ls.d(1, function(_, _, _, ...)
    local lines = {}
    for line in io.lines(path) do
      table.insert(lines, line)
    end
    return ls.sn(nil, require('luasnip.extras.fmt').fmt(table.concat(lines, '\n'), ...))
  end, {}, { user_args = { vargs } })
end

ls.setup({
  ext_opts = {
    [types.snippet] = {
      active = {
        virt_text = { { '<-- snippet', 'LuasnipIndicator' } },
        virt_text_pos = 'right_align',
      },
    },
    [types.insertNode] = {
      unvisited = { hl_group = 'LuasnipIndicator' },
    },
    [types.choiceNode] = {
      active = {
        virt_text = { { '<-- choice node', 'LuasnipIndicator' } },
      },
    },
  },

  snip_env = vim.tbl_extend('keep', ls.session.config.snip_env, {
    autowrap = autowrap,
    exec = exec,
    comment = comment,
    file_contents = file_contents,

    user_email = {
      exec([[git config --get user.name]]),
      ls.t(' <'),
      ls.c(1, {
        exec([[git config --get user.email]]),
        ls.t([[robert.gunzler@postman.com]]),
        ls.t([[robert@gnzler.io]]),
      }),
      ls.t('>'),
    },
  }),
})

-- snipmate snippets
require('luasnip.loaders.from_snipmate').lazy_load({ paths = './after/snippets' })
-- lua snippets
require('luasnip.loaders.from_lua').lazy_load({ paths = './snippets' })

vim.api.nvim_create_user_command('LuaSnipUnlinkAll', function()
  while #package.loaded.luasnip.session.current_nodes > 0 do
    package.loaded.luasnip.unlink_current()
  end
end, { desc = 'unlink all active snippets' })