local status_ok, cmp = pcall(require, "cmp")
if not status_ok then
	return
end

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

-- insert '()' after completing a function
cmp.event:on('confirm_done',
  require('nvim-autopairs.completion.cmp').on_confirm_done())

local luasnip = require('luasnip')
local neogen = require('neogen')
require("luasnip.loaders.from_vscode").lazy_load()

cmp.setup {
  snippet = {
    expand = function(args)
      luasnip.lsp_expand(args.body)
    end,
  },

  sources = cmp.config.sources({
    { name = 'nvim_lsp', keyword_length = 3 },
    { name = 'luasnip_choice' },
    { name = 'async_path' },
    { name = 'buffer', keyword_length = 3, max_item_count = 7 },
    { name = 'calc' },
    { name = 'neorg' },
  }),
  window = {
    completion = {
      border = { ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ' },
      winhighlight = "Normal:WinBarNC,FloatBorder:WinBarNC,Search:WinBarNC",
    },
    documentation = {
      border = { ' ', ' ', ' ', ' ', ' ', ' ', ' ', ' ' },
      winhighlight = "Normal:WinBarNC,FloatBorder:WinBarNC,Search:WinBarNC",
    }
  },
  view = {
    entries = { name = 'custom', selection_order = 'near_cursor' },
  },

  -- mappings -----------------------------------------------------------------
  mapping = cmp.mapping.preset.insert({
    ["<Tab>"] = cmp.mapping(function(fallback)
      if #cmp.get_entries() == 1 then
        cmp.confirm({ select = true })
      elseif cmp.visible() then
        cmp.select_next_item()
      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
      elseif neogen.jumpable() then
        neogen.jump_next()
      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)
      elseif neogen.jumpable(true) then
        neogen.jump_prev()
      else
        fallback()
      end
    end, { "i", "s" }),
    ['<CR>'] = cmp.mapping {
      i = function(fallback)
        if cmp.visible() and cmp.get_active_entry() then
          cmp.confirm({ behavior = cmp.ConfirmBehavior.Replace, select = false })
        else
          fallback()
        end
      end,
      s = cmp.mapping.confirm({ select = true }),
      c = cmp.mapping.confirm({ behavior = cmp.ConfirmBehavior.Replace,
        select = true }),
    },
    ["<C-u>"] = cmp.mapping.scroll_docs(-4),
    ["<C-d>"] = cmp.mapping.scroll_docs(4),
    ['<ESC>'] = cmp.mapping.close(),
    ["<C-e>"] = cmp.mapping.abort(),
  }),

  sorting = {
    comparators = {
      cmp.config.compare.offset,
      cmp.config.compare.exact,
      cmp.config.compare.score,
      require("cmp-under-comparator").under,
      cmp.config.compare.kind,
      cmp.config.compare.sort_text,
      cmp.config.compare.length,
      cmp.config.compare.order,
    }
  },
  enabled = function()
    local context = require 'cmp.config.context'
    if a.nvim_get_mode().mode == 'c' then
      return true
    else
      return not context.in_treesitter_capture("comment")
        and not context.in_syntax_group("Comment")
    end
  end
}