---@module 'lazy'
---@type LazySpec
return {
  { -- Highlight, edit, and navigate code
    'nvim-treesitter/nvim-treesitter',
    lazy = false,
    build = ':TSUpdate',
    branch = 'main',
    -- [[ Configure Treesitter ]] See `:help nvim-treesitter-intro`
    config = function()
      -- ensure basic parser are installed
      local parsers = { 'bash', 'c', 'diff', 'html', 'lua', 'luadoc', 'markdown', 'markdown_inline', 'query', 'vim', 'vimdoc' }
      require('nvim-treesitter').install(parsers)

      ---@param buf integer
      ---@param language string
      local function treesitter_try_attach(buf, language)
        -- check if parser exists and load it
        if not vim.treesitter.language.add(language) then return end
        -- enables syntax highlighting and other treesitter features
        vim.treesitter.start(buf, language)

        -- enables treesitter based folds
        -- for more info on folds see `:help folds`
        -- vim.wo.foldexpr = 'v:lua.vim.treesitter.foldexpr()'
        -- vim.wo.foldmethod = 'expr'

        -- check if treesitter indentation is available for this language, and if so enable it
        -- in case there is no indent query, the indentexpr will fallback to the vim's built in one
        local has_indent_query = vim.treesitter.query.get(language, 'indent') ~= nil

        -- enables treesitter based indentation
        if has_indent_query then vim.bo.indentexpr = "v:lua.require'nvim-treesitter'.indentexpr()" end
      end

      local available_parsers = require('nvim-treesitter').get_available()
      vim.api.nvim_create_autocmd('FileType', {
        callback = function(args)
          local buf, filetype = args.buf, args.match

          local language = vim.treesitter.language.get_lang(filetype)
          if not language then return end

          local installed_parsers = require('nvim-treesitter').get_installed 'parsers'

          if vim.tbl_contains(installed_parsers, language) then
            -- enable the parser if it is installed
            treesitter_try_attach(buf, language)
          elseif vim.tbl_contains(available_parsers, language) then
            -- if a parser is available in `nvim-treesitter` auto install it, and enable it after the installation is done
            require('nvim-treesitter').install(language):await(function() treesitter_try_attach(buf, language) end)
          else
            -- try to enable treesitter features in case the parser exists but is not available from `nvim-treesitter`
            treesitter_try_attach(buf, language)
          end
        end,
      })
    end,
  },
}
-- vim: ts=2 sts=2 sw=2 et