local helpers = require('test.functional.helpers')(after_each)

local clear = helpers.clear
local command = helpers.command
local dedent = helpers.dedent
local eval = helpers.eval
local eq = helpers.eq
local feed = helpers.feed
local nvim = helpers.nvim
local redir_exec = helpers.redir_exec

describe('TabNewEntered', function()
  describe('au TabNewEntered', function()
    describe('with * as <afile>', function()
      it('matches when entering any new tab', function()
        clear()
        nvim('command', 'au! TabNewEntered * echom "tabnewentered:".tabpagenr().":".bufnr("")')
        eq("tabnewentered:2:2", nvim('exec', 'tabnew', true))
        eq("tabnewentered:3:3", nvim('exec', 'tabnew test.x2', true))
     end)
    end)
    describe('with FILE as <afile>', function()
      it('matches when opening a new tab for FILE', function()
        nvim('command', 'au! TabNewEntered Xtest-tabnewentered echom "tabnewentered:match"')
        eq('tabnewentered:4:4\ntabnewentered:match',
          nvim('exec', 'tabnew Xtest-tabnewentered', true))
     end)
    end)
    describe('with CTRL-W T', function()
      it('works when opening a new tab with CTRL-W T', function()
        clear()
        nvim('command', 'au! TabNewEntered * echom "entered"')
        nvim('command', 'tabnew test.x2')
        nvim('command', 'split')
        eq('entered', nvim('exec', 'execute "normal \\<C-W>T"', true))
      end)
    end)
  end)
end)

describe('TabEnter', function()
  before_each(clear)
  it('has correct previous tab when entering any new tab', function()
     command('augroup TEMP')
     nvim('command', 'au! TabEnter * echom "tabenter:".tabpagenr().":".tabpagenr(\'#\')')
     command('augroup END')
     eq("tabenter:2:1", nvim('exec', 'tabnew', true))
     eq("tabenter:3:2", nvim('exec', 'tabnew test.x2', true))
     command('augroup! TEMP')
  end)
  it('has correct previous tab when entering any preexisting tab', function()
     command('tabnew')
     command('tabnew')
     command('augroup TEMP')
     nvim('command', 'au! TabEnter * echom "tabenter:".tabpagenr().":".tabpagenr(\'#\')')
     command('augroup END')
     eq("tabenter:1:3", nvim('exec', 'tabnext', true))
     eq("tabenter:2:1", nvim('exec', 'tabnext', true))
     command('augroup! TEMP')
  end)
end)

describe('tabpage/previous', function()
  before_each(clear)
  local function switches_to_previous_after_new_tab_creation_at_end(characters)
    return function()
        -- Add three tabs for a total of four
        command('tabnew')
        command('tabnew')
        command('tabnew')

        -- The previous tab is now the third.
        eq(3, eval('tabpagenr(\'#\')'))

        -- Switch to the previous (third) tab
        feed(characters)

        eq(dedent([=[


          Tab page 1
              [No Name]
          Tab page 2
              [No Name]
          Tab page 3
          >   [No Name]
          Tab page 4
              [No Name]]=]),
           redir_exec('tabs')
        )

        -- The previous tab is now the fourth.
        eq(4, eval('tabpagenr(\'#\')'))
    end
  end
  it('switches to previous via g<Tab> after new tab creation at end',
    switches_to_previous_after_new_tab_creation_at_end('g<Tab>'))
  it('switches to previous via <C-W>g<Tab>. after new tab creation at end', switches_to_previous_after_new_tab_creation_at_end('<C-W>g<Tab>'))
  it('switches to previous via <C-Tab>. after new tab creation at end', switches_to_previous_after_new_tab_creation_at_end('<C-Tab>'))

  local function switches_to_previous_after_new_tab_creation_in_middle(characters)
    return function()
      -- Add three tabs for a total of four
      command('tabnew')
      command('tabnew')
      command('tabnew')
      -- Switch to the second tab
      command('tabnext 2')
      -- Add a new tab after the second tab
      command('tabnew')

      -- The previous tab is now the second.
      eq(2, eval('tabpagenr(\'#\')'))

      -- Switch to the previous (second) tab
      feed(characters)
      eq(dedent([=[


         Tab page 1
             [No Name]
         Tab page 2
         >   [No Name]
         Tab page 3
             [No Name]
         Tab page 4
             [No Name]
         Tab page 5
             [No Name]]=]),
         redir_exec('tabs')
      )

      -- The previous tab is now the third.
      eq(3, eval('tabpagenr(\'#\')'))
    end
  end
  it('switches to previous via g<Tab> after new tab creation in middle',
    switches_to_previous_after_new_tab_creation_in_middle('g<Tab>'))
  it('switches to previous via <C-W>g<Tab> after new tab creation in middle',
    switches_to_previous_after_new_tab_creation_in_middle('<C-W>g<Tab>'))
  it('switches to previous via <C-Tab> after new tab creation in middle',
    switches_to_previous_after_new_tab_creation_in_middle('<C-Tab>'))

  local function switches_to_previous_after_switching_to_next_tab(characters)
    return function()
      -- Add three tabs for a total of four
      command('tabnew')
      command('tabnew')
      command('tabnew')
      -- Switch to the next (first) tab
      command('tabnext')

      -- The previous tab is now the fourth.
      eq(4, eval('tabpagenr(\'#\')'))

      -- Switch to the previous (fourth) tab
      feed(characters)

      eq(dedent([=[


         Tab page 1
             [No Name]
         Tab page 2
             [No Name]
         Tab page 3
             [No Name]
         Tab page 4
         >   [No Name]]=]),
         redir_exec('tabs')
      )

      -- The previous tab is now the first.
      eq(1, eval('tabpagenr(\'#\')'))
    end
  end
  it('switches to previous via g<Tab> after switching to next tab',
    switches_to_previous_after_switching_to_next_tab('g<Tab>'))
  it('switches to previous via <C-W>g<Tab> after switching to next tab',
    switches_to_previous_after_switching_to_next_tab('<C-W>g<Tab>'))
  it('switches to previous via <C-Tab> after switching to next tab',
    switches_to_previous_after_switching_to_next_tab('<C-Tab>'))

  local function switches_to_previous_after_switching_to_last_tab(characters)
    return function()
      -- Add three tabs for a total of four
      command('tabnew')
      command('tabnew')
      command('tabnew')
      -- Switch to the next (first) tab
      command('tabnext')
      -- Switch to the last (fourth) tab.
      command('tablast')

      -- The previous tab is now the second.
      eq(1, eval('tabpagenr(\'#\')'))

      -- Switch to the previous (second) tab
      feed(characters)

      eq(dedent([=[


         Tab page 1
         >   [No Name]
         Tab page 2
             [No Name]
         Tab page 3
             [No Name]
         Tab page 4
             [No Name]]=]),
         redir_exec('tabs')
      )

      -- The previous tab is now the fourth.
      eq(4, eval('tabpagenr(\'#\')'))
    end
  end
  it('switches to previous after switching to last tab',
    switches_to_previous_after_switching_to_last_tab('g<Tab>'))
  it('switches to previous after switching to last tab',
    switches_to_previous_after_switching_to_last_tab('<C-W>g<Tab>'))
  it('switches to previous after switching to last tab',
    switches_to_previous_after_switching_to_last_tab('<C-Tab>'))

  local function switches_to_previous_after_switching_to_previous_tab(characters)
    return function()
      -- Add three tabs for a total of four
      command('tabnew')
      command('tabnew')
      command('tabnew')
      -- Switch to the previous (third) tab
      command('tabprevious')

      -- The previous tab is now the fourth.
      eq(4, eval('tabpagenr(\'#\')'))

      -- Switch to the previous (fourth) tab
      feed(characters)

      eq(dedent([=[


         Tab page 1
             [No Name]
         Tab page 2
             [No Name]
         Tab page 3
             [No Name]
         Tab page 4
         >   [No Name]]=]),
         redir_exec('tabs')
      )

      -- The previous tab is now the third.
      eq(3, eval('tabpagenr(\'#\')'))
    end
  end
  it('switches to previous via g<Tab> after switching to previous tab',
    switches_to_previous_after_switching_to_previous_tab('g<Tab>'))
  it('switches to previous via <C-W>g<Tab> after switching to previous tab',
    switches_to_previous_after_switching_to_previous_tab('<C-W>g<Tab>'))
  it('switches to previous via <C-Tab> after switching to previous tab',
    switches_to_previous_after_switching_to_previous_tab('<C-Tab>'))

  local function switches_to_previous_after_switching_to_first_tab(characters)
    return function()
      -- Add three tabs for a total of four
      command('tabnew')
      command('tabnew')
      command('tabnew')
      -- Switch to the previous (third) tab
      command('tabprevious')
      -- Switch to the first tab
      command('tabfirst')

      -- The previous tab is now the third.
      eq(3, eval('tabpagenr(\'#\')'))

      -- Switch to the previous (third) tab
      feed(characters)

      eq(dedent([=[


         Tab page 1
             [No Name]
         Tab page 2
             [No Name]
         Tab page 3
         >   [No Name]
         Tab page 4
             [No Name]]=]),
         redir_exec('tabs')
      )

      -- The previous tab is now the first.
      eq(1, eval('tabpagenr(\'#\')'))
    end
  end
  it('switches to previous via g<Tab> after switching to first tab',
    switches_to_previous_after_switching_to_first_tab('g<Tab>'))
  it('switches to previous via <C-W>g<Tab> after switching to first tab',
    switches_to_previous_after_switching_to_first_tab('<C-W>g<Tab>'))
  it('switches to previous via <C-Tab> after switching to first tab',
    switches_to_previous_after_switching_to_first_tab('<C-Tab>'))

  local function switches_to_previous_after_numbered_tab_switch(characters)
    return function()
      -- Add three tabs for a total of four
      command('tabnew')
      command('tabnew')
      command('tabnew')
      -- Switch to the second tab
      command('tabnext 2')

      -- The previous tab is now the fourth.
      eq(4, eval('tabpagenr(\'#\')'))

      -- Switch to the previous (fourth) tab
      feed(characters)

      eq(dedent([=[


         Tab page 1
             [No Name]
         Tab page 2
             [No Name]
         Tab page 3
             [No Name]
         Tab page 4
         >   [No Name]]=]),
         redir_exec('tabs')
      )

      -- The previous tab is now the second.
      eq(2, eval('tabpagenr(\'#\')'))
    end
  end
  it('switches to previous via g<Tab> after numbered tab switch',
    switches_to_previous_after_numbered_tab_switch('g<Tab>'))
  it('switches to previous via <C-W>g<Tab> after numbered tab switch',
    switches_to_previous_after_numbered_tab_switch('<C-W>g<Tab>'))
  it('switches to previous via <C-Tab> after numbered tab switch',
    switches_to_previous_after_numbered_tab_switch('<C-Tab>'))

  local function switches_to_previous_after_switching_to_previous(characters1, characters2)
    return function()
      -- Add three tabs for a total of four
      command('tabnew')
      command('tabnew')
      command('tabnew')
      -- Switch to the second tab
      command('tabnext 2')
      -- Switch to the previous (fourth) tab
      feed(characters1)

      -- The previous tab is now the second.
      eq(2, eval('tabpagenr(\'#\')'))

      -- Switch to the previous (second) tab
      feed(characters2)

      eq(dedent([=[


         Tab page 1
             [No Name]
         Tab page 2
         >   [No Name]
         Tab page 3
             [No Name]
         Tab page 4
             [No Name]]=]),
         redir_exec('tabs')
      )

      -- The previous tab is now the fourth.
      eq(4, eval('tabpagenr(\'#\')'))
    end
  end
  it('switches to previous via g<Tab> after switching to previous via g<Tab>',
    switches_to_previous_after_switching_to_previous('g<Tab>', 'g<Tab>'))
  it('switches to previous via <C-W>g<Tab> after switching to previous via g<Tab>',
    switches_to_previous_after_switching_to_previous('g<Tab>', '<C-W>g<Tab>'))
  it('switches to previous via <C-Tab> after switching to previous via g<Tab>',
    switches_to_previous_after_switching_to_previous('g<Tab>', '<C-Tab>'))
  it('switches to previous via g<Tab> after switching to previous via <C-W>g<Tab>',
    switches_to_previous_after_switching_to_previous('<C-W>g<Tab>', 'g<Tab>'))
  it('switches to previous via <C-W>g<Tab> after switching to previous via <C-W>g<Tab>',
    switches_to_previous_after_switching_to_previous('<C-W>g<Tab>', '<C-W>g<Tab>'))
  it('switches to previous via <C-Tab> after switching to previous via <C-W>g<Tab>',
    switches_to_previous_after_switching_to_previous('<C-W>g<Tab>', '<C-Tab>'))
  it('switches to previous via g<Tab> after switching to previous via <C-Tab>',
    switches_to_previous_after_switching_to_previous('<C-Tab>', 'g<Tab>'))
  it('switches to previous via <C-W>g<Tab> after switching to previous via <C-Tab>',
    switches_to_previous_after_switching_to_previous('<C-Tab>', '<C-W>g<Tab>'))
  it('switches to previous via <C-Tab> after switching to previous via <C-Tab>',
    switches_to_previous_after_switching_to_previous('<C-Tab>', '<C-Tab>'))

  local function does_not_switch_to_previous_after_closing_current_tab(characters)
    return function()
      -- Add three tabs for a total of four
      command('tabnew')
      command('tabnew')
      command('tabnew')
      -- Close the current (fourth tab)
      command('wincmd c')

      -- The previous tab is now the "zeroth" -- there isn't one.
      eq(0, eval('tabpagenr(\'#\')'))

      -- At this point, switching to the "previous" (i.e. fourth) tab would mean
      -- switching to either a dangling or a null pointer.
      feed(characters)

      eq(dedent([=[


         Tab page 1
             [No Name]
         Tab page 2
             [No Name]
         Tab page 3
         >   [No Name]]=]),
         redir_exec('tabs')
      )

      -- The previous tab is now the "zero".
      eq(0, eval('tabpagenr(\'#\')'))
    end
  end
  it('does not switch to previous via g<Tab> after closing current tab',
    does_not_switch_to_previous_after_closing_current_tab('g<Tab>'))
  it('does not switch to previous via <C-W>g<Tab> after closing current tab',
    does_not_switch_to_previous_after_closing_current_tab('<C-W>g<Tab>'))
  it('does not switch to previous via <C-Tab> after closing current tab',
    does_not_switch_to_previous_after_closing_current_tab('<C-Tab>'))

  local function does_not_switch_to_previous_after_entering_operator_pending(characters)
      return function()
          -- Add three tabs for a total of four
          command('tabnew')
          command('tabnew')
          command('tabnew')

          -- The previous tab is now the third.
          eq(3, eval('tabpagenr(\'#\')'))

          -- Enter operator pending mode.
          feed('d')
          eq('no', eval('mode(1)'))

          -- At this point switching to the previous tab should have no effect
          -- other than leaving operator pending mode.
          feed(characters)

          -- Attempting to switch tabs returns us to normal mode.
          eq('n', eval('mode()'))

          -- The current tab is still the fourth.
          eq(4, eval('tabpagenr()'))

          -- The previous tab is still the third.
          eq(3, eval('tabpagenr(\'#\')'))
      end
  end
  it('does not switch to previous via g<Tab> after entering operator pending',
    does_not_switch_to_previous_after_entering_operator_pending('g<Tab>'))
  -- NOTE: When in operator pending mode, attempting to switch to previous has
  --       the following effect:
  --       - Ctrl-W exits operator pending mode
  --       - g<Tab> switches to the previous tab
  --       In other words, the effect of "<C-W>g<Tab>" is to switch to the
  --       previous tab even from operator pending mode, but only thanks to the
  --       fact that the suffix after "<C-W>" in "<C-W>g<Tab>" just happens to
  --       be the same as the normal mode command to switch to the previous tab.
  -- it('does not switch to previous via <C-W>g<Tab> after entering operator pending',
  --   does_not_switch_to_previous_after_entering_operator_pending('<C-W>g<Tab>'))
  it('does not switch to previous via <C-Tab> after entering operator pending',
    does_not_switch_to_previous_after_entering_operator_pending('<C-Tab>'))
end)