require('gitsigns').setup {
  on_attach = function(bufnr)
    local gs = package.loaded.gitsigns

    local function map(mode, l, r, opts)
      opts = opts or {}
      opts.buffer = bufnr
      vim.keymap.set(mode, l, r, opts)
    end

    -- map leader gj to go to next hunk
    map('n', '<leader>gj', function()
      if vim.wo.diff then return ']c' end
      vim.schedule(function() gs.next_hunk() end)
      return '<Ignore>'
    end, { expr = true })

    -- map leader gk to go to previous hunk
    map('n', '<leader>gk', function()
      if vim.wo.diff then return '[c' end
      vim.schedule(function() gs.prev_hunk() end)
      return '<Ignore>'
    end, { expr = true })

    map('n', '<leader>gp', gs.preview_hunk)
    map('n', '<leader>gs', gs.stage_hunk)
    map('v', '<leader>gs', function() gs.stage_hunk { vim.fn.line('.'), vim.fn.line('v') } end)
    map('n', '<leader>gu', gs.reset_hunk)

    -- nnoremap <leader>glf :!smerge log %<CR>
    map('n', '<leader>glf', function()
      vim.fn.system('smerge log ' .. vim.fn.expand('%'))
    end)
    -- nnoremap <leader>gbf :!smerge blame % line('.')<CR>
    map('n', '<leader>gbf', function()
      vim.fn.system('smerge blame ' .. vim.fn.expand('%') .. ' ' .. vim.fn.line('.'))
    end)
  end
}