local cmp = require'cmp'
local luasnip = require'luasnip'

local has_words_before = function()
  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({
  formatting = {
    format = require('lspkind').cmp_format({
      with_text = true,
      menu = {
        buffer = "[Buffer]",
        tmux = "[Tmux]",
        luasnip = "[LuaSnip]",
        nvim_lsp = "[LSP]",
        nvim_lua = "[Lua]",
        path = "[Path]",
      },
    }),
  },

  window = {
    completion = cmp.config.window.bordered({
      winhighlight = 'Normal:PMenu,FloatBorder:PMenuBorder,CursorLine:PMenuSel,Search:None',
    }),
    documentation = cmp.config.window.bordered({
      winhighlight = 'Normal:PMenu,FloatBorder:PMenu,CursorLine:PMenuSel,Search:None',
    }),
  },

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

  mapping = {
    ['<Up>'] = cmp.mapping(cmp.mapping.select_prev_item(), { 'i', 'c' }),
    ['<Down>'] = cmp.mapping(cmp.mapping.select_next_item(), { 'i', 'c' }),
    ['<C-p>'] = cmp.mapping(cmp.mapping.select_prev_item(), { 'i', 'c' }),
    ['<C-n>'] = cmp.mapping(cmp.mapping.select_next_item(), { 'i', 'c' }),
    ["<C-d>"] = cmp.mapping.scroll_docs(-4),
    ["<C-u>"] = cmp.mapping.scroll_docs(4),
    ['<C-e>'] = cmp.mapping({
      i = cmp.mapping.abort(),
      c = cmp.mapping.close(),
    }),
    ['<CR>'] = cmp.mapping(cmp.mapping.confirm({ select = false }), { 'i', 'c' }),
    ['<C-y>'] = cmp.mapping(cmp.mapping.confirm({ select = false }), { 'i', 'c' }),
    ['<C-Space>'] = cmp.mapping(cmp.mapping.complete(), { 'i', 'c' }),
    ["<Tab>"] = cmp.mapping(function(fallback)
      if 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()
      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" }),
  },

  sources = cmp.config.sources({
    {
      name = 'buffer',
      priority = 1,

    },
    {
      name = 'luasnip',
      priority = 4,
    },
    {
      name = 'tmux',
      priority = 2,
      option = {
        all_panes = true,
        trigger_characters = {},
      }
    },
    {
      name = 'nvim_lsp',
      priority = 3,
    },
  })
})