local has_words_before = function()
  unpack = unpack or table.unpack
  local line, col = unpack(vim.api.nvim_win_get_cursor(0))
  return col ~= 0 and vim.api.nvim_buf_get_lines(
    0, 
    line - 1, 
    line, 
    true
  )[1]:sub(col, col):match('%s') == nil
end

-- Add additional capabilities supported by nvim-cmp
local capabilities = require('cmp_nvim_lsp').default_capabilities()
local luasnip = require("luasnip")

local kind_icons = {
  Text = "",
  Method = "",
  Function = "",
  Constructor = "",
  Field = "",
  Variable = "",
  Class = "ﴯ",
  Interface = "",
  Module = "",
  Property = "ﰠ",
  Unit = "",
  Value = "",
  Enum = "",
  Keyword = "",
  Snippet = "",
  Color = "",
  File = "",
  Reference = "",
  Folder = "",
  EnumMember = "",
  Constant = "",
  Struct = "",
  Event = "",
  Operator = "",
  TypeParameter = ""
}

-- nvim-cmp setup
local cmp = require 'cmp'
cmp.setup {
  mapping = {
    ["<Tab>"] = cmp.mapping(function(fallback)
      if cmp.visible() then
        cmp.select_next_item()
      -- You could replace the expand_or_jumpable() calls with expand_or_locally_jumpable() 
      -- they way you will only jump inside the snippet region
      elseif luasnip.expand_or_jumpable() then
        luasnip.expand_or_jump()
      elseif has_words_before() then
        cmp.complete()
      else
        fallback()
      end
    end, { "i", "s" }),

    ["<S-Tab>"] = cmp.mapping(function(fallback)
      if cmp.visible() then
        cmp.select_prev_item()
      elseif luasnip.jumpable(-1) then
        luasnip.jump(-1)
      else
        fallback()
      end
    end, { "i", "s" }),
  },
  formatting = {
    format = function(_, vim_item)
      vim_item.kind = string.format('%s %s', kind_icons[vim_item.kind], vim_item.kind)
      return vim_item
    end,
  },
  sources = {
    { name = 'nvim_lsp' },
    { name = 'luasnip' }, 
    { name = 'path' },
    { name = 'buffer' },
  },
}