local api = vim.api
local au = api.nvim_create_autocmd
local group = api.nvim_create_augroup('core.events', { clear = true })

-- Automatically create a scratch buffer if Neovim starts with no files
au('VimEnter', {
  group = group,
  callback = function()
    -- Only trigger if no file arguments are passed
    if vim.fn.argc() == 0 then
      vim.cmd('enew')
      vim.bo.buftype = 'nofile'
      vim.bo.bufhidden = 'wipe'
      vim.bo.swapfile = false
    end
  end,
})

-- Highlight when yanking (copying) text
au('TextYankPost', {
  group = group,
  callback = function()
    vim.highlight.on_yank({ timeout = 400 })
  end,
})

-- Disable comment continuation only when using 'o'/'O', but keep it for <Enter>
au('FileType', {
  group = group,
  pattern = '*',
  callback = function()
    vim.opt_local.formatoptions:remove('o')
  end,
})

-- Show cursor line only in active window
au({ 'WinEnter', 'InsertLeave' }, {
  group = group,
  callback = function()
    if vim.w.auto_cursorline then
      vim.wo.cursorline = true
      vim.w.auto_cursorline = nil
    end
  end,
})

au({ 'WinLeave', 'InsertEnter' }, {
  group = group,
  callback = function()
    if vim.bo.filetype == 'NvimTree' then
      return
    end
    if vim.wo.cursorline then
      vim.w.auto_cursorline = true
      vim.wo.cursorline = false
    end
  end,
})

-- Autocompletion
au('LspAttach', {
  group = group,
  callback = function(ev)
    local client = vim.lsp.get_client_by_id(ev.data.client_id)
    if not client then
      return
    end

    -- Enable native completion
    if client:supports_method('textDocument/completion') then
      vim.lsp.completion.enable(true, client.id, ev.buf, { autotrigger = true })
    end
  end,
})
vim.lsp.handlers['textDocument/completion'] = function(err, result, ctx, config)
  if err or not result then
    return
  end
  for _, item in ipairs(result.items or result) do
    if item.kind then
      local kind = vim.lsp.protocol.CompletionItemKind[item.kind] or ''
      item.menu = '[' .. kind .. ']'
    end
  end
  return vim.lsp.completion._on_completion_result(err, result, ctx, config)
end

au('InsertEnter', {
  group = group,
  once = true,
  callback = function()
    require('nvim-ts-autotag').setup()
    require('nvim-autopairs').setup()
  end,
})

require('modules.theme')
au('UIEnter', {
  group = group,
  once = true,
  callback = function()
    vim.schedule(function()
      require('modules.navigation')
      require('plugins.language-manager').setup()
      require('modules.diagnostics')
    end)
  end,
})