-- See `:help cmp`
local cmp = require 'cmp'
local luasnip = require 'luasnip'
require('luasnip.loaders.from_vscode').lazy_load()
require('luasnip.loaders.from_lua').lazy_load()
luasnip.config.setup {
  history = true,
  updateevents = "TextChanged,TextChangedI",
  enable_autosnippets = true,
}
luasnip.filetype_extend("jj", { "gitcommit" })

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

cmp.setup {
  snippet = {
    expand = function(args)
      luasnip.lsp_expand(args.body)
    end,
  },
  completion = {
    completeopt = 'menu,menuone,noinsert',
    autocomplete = false,
  },
  mapping = cmp.mapping.preset.insert {
    ['<C-n>'] = cmp.mapping.select_next_item(),
    ['<C-p>'] = cmp.mapping.select_prev_item(),
    ['<C-b>'] = cmp.mapping.scroll_docs(-4),
    ['<C-f>'] = cmp.mapping.scroll_docs(4),
    ['<C-Space>'] = cmp.mapping.complete {},
    ['<CR>'] = cmp.mapping.confirm {
      behavior = cmp.ConfirmBehavior.Replace,
      select = true,
    },
    ['<C-e>'] = cmp.mapping({ i = cmp.mapping.abort(), c = cmp.mapping.close() }),
    ['<Tab>'] = cmp.mapping(function(fallback)
      if cmp.visible() then
        if #cmp.get_entries() == 1 then
          cmp.confirm({ select = true })
        else
          cmp.select_next_item()
        end
      elseif luasnip.expand_or_locally_jumpable() then
        luasnip.expand_or_jump()
      elseif has_words_before() then
        cmp.complete()
        if #cmp.get_entries() == 1 then
          cmp.confirm({ select = true })
        end
      else
        fallback()
      end
    end, { 'i', 's' }),
    ['<S-Tab>'] = cmp.mapping(function(fallback)
      if cmp.visible() then
        cmp.select_prev_item()
      elseif luasnip.locally_jumpable(-1) then
        luasnip.jump(-1)
      else
        fallback()
      end
    end, { 'i', 's' }),
  },
  sources = {
    { name = 'lazydev',
      group_index = 0 },
    { name = 'nvim_lsp' },
    { name = 'nvim_lsp' },
    { name = 'luasnip' },
    { name = 'path' },
  },
}