-- luasnip setup
local luasnip = require 'luasnip'

local cmp = require 'cmp'

cmp.setup {
  snippet = {
    expand = function(args)
      require('luasnip').lsp_expand(args.body)
    end,
  },
  mapping = {
    ['<C-p>'] = cmp.mapping.select_prev_item(),
    ['<C-n>'] = cmp.mapping.select_next_item(),
    ['<C-d>'] = cmp.mapping.scroll_docs(-4),
    ['<C-f>'] = cmp.mapping.scroll_docs(4),
    ['<C-Space>'] = cmp.mapping.complete(),
    ['<C-e>'] = cmp.mapping.close(),
    ['<CR>'] = cmp.mapping.confirm {
      behavior = cmp.ConfirmBehavior.Replace,
      select = true,
    },
    ['<Tab>'] = function(fallback)
      if vim.fn.pumvisible() == 1 then
        vim.fn.feedkeys(vim.api.nvim_replace_termcodes('<C-n>', true, true, true), 'n')
      elseif luasnip.expand_or_jumpable() then
        vim.fn.feedkeys(vim.api.nvim_replace_termcodes('<Plug>luasnip-expand-or-jump', true, true, true), '')
      else
        fallback()
      end
    end,
    ['<S-Tab>'] = function(fallback)
      if vim.fn.pumvisible() == 1 then
        vim.fn.feedkeys(vim.api.nvim_replace_termcodes('<C-p>', true, true, true), 'n')
      elseif luasnip.jumpable(-1) then
        vim.fn.feedkeys(vim.api.nvim_replace_termcodes('<Plug>luasnip-jump-prev', true, true, true), '')
      else
        fallback()
      end
    end,
  },
  sources = {
    { name = 'nvim_lsp' },
    { name = 'luasnip' },
  },
}

-- The nvim-cmp almost supports LSP's capabilities so You should advertise it to LSP servers..
local capabilities = vim.lsp.protocol.make_client_capabilities()
capabilities = require('cmp_nvim_lsp').update_capabilities(capabilities)