local auto = require('std.auto')

describe('std.auto', function()
  after_each(function()
    vim.api.nvim_del_augroup_by_name('test_group')
  end)

  describe('group-scoped autocmds (no buffer)', function()
    it('should register and fire a group autocmd', function()
      local fired = false
      auto 'test_group' {
        events = 'User',
        pattern = 'TestEvent',
        command = function() fired = true end,
      }
      vim.cmd('doautocmd User TestEvent')
      assert.is_true(fired)
    end)

    it('should pass group to nvim_create_autocmd', function()
      auto 'test_group' {
        events = 'User',
        pattern = 'TestGroupScoped',
        command = function() end,
      }
      local autocmds = vim.api.nvim_get_autocmds({ group = 'test_group' })
      assert.is_true(#autocmds > 0)
    end)
  end)

  describe('buffer-local autocmds (with buffer)', function()
    it('should fire a buffer-local autocmd', function()
      local buf = vim.api.nvim_create_buf(true, false)
      local fired = false
      auto 'test_group' {
        events = 'BufWinEnter',
        buffer = buf,
        command = function() fired = true end,
      }
      vim.api.nvim_exec_autocmds('BufWinEnter', { buf = buf })
      assert.is_true(fired)
      vim.api.nvim_buf_delete(buf, { force = true })
    end)

    it('should respect once = true for buffer-local autocmds', function()
      local buf = vim.api.nvim_create_buf(true, false)
      local count = 0
      auto 'test_group' {
        events = 'BufWinEnter',
        buffer = buf,
        once = true,
        command = function() count = count + 1 end,
      }
      vim.api.nvim_exec_autocmds('BufWinEnter', { buf = buf })
      assert.equal(1, count)
      vim.api.nvim_exec_autocmds('BufWinEnter', { buf = buf })
      assert.equal(1, count)
      vim.api.nvim_buf_delete(buf, { force = true })
    end)

    it('should auto-clean when buffer is deleted', function()
      local buf = vim.api.nvim_create_buf(true, false)
      auto 'test_group' {
        events = 'BufWinEnter',
        buffer = buf,
        command = function() end,
      }
      vim.api.nvim_buf_delete(buf, { force = true })
      local autocmds = vim.api.nvim_get_autocmds({ event = 'BufWinEnter' })
      local found = false
      for _, a in ipairs(autocmds) do
        if a.buf == buf then
          found = true
          break
        end
      end
      assert.is_false(found)
    end)
  end)

  describe('multiple autocmds in one call', function()
    it('should fire both autocmds when their events fire', function()
      local fired_a, fired_b = false, false
      auto 'test_group' {
        {
          events = 'User',
          pattern = 'MultiA',
          command = function() fired_a = true end,
        },
        {
          events = 'User',
          pattern = 'MultiB',
          command = function() fired_b = true end,
        },
      }
      vim.cmd('doautocmd User MultiA')
      vim.cmd('doautocmd User MultiB')
      assert.is_true(fired_a)
      assert.is_true(fired_b)
    end)
  end)

  describe('description field', function()
    it('should preserve description in the autocmd', function()
      auto 'test_group' {
        events = 'User',
        pattern = 'DescTest',
        description = 'my test description',
        command = function() end,
      }
      local autocmds = vim.api.nvim_get_autocmds({ group = 'test_group' })
      assert.equal(1, #autocmds)
      assert.equal('my test description', autocmds[1].desc)
    end)
  end)

  describe('pattern filter', function()
    it('should only fire when pattern matches', function()
      local fired = false
      auto 'test_group' {
        events = 'BufWritePost',
        pattern = '*.lua',
        command = function() fired = true end,
      }
      vim.api.nvim_exec_autocmds('BufWritePost', { pattern = 'foo.txt' })
      assert.is_false(fired)
      vim.api.nvim_exec_autocmds('BufWritePost', { pattern = 'bar.lua' })
      assert.is_true(fired)
    end)
  end)

  describe('group clearing (idempotency)', function()
    it('should clear previous autocmds when re-calling with same group name', function()
      local first_called, second_called = false, false
      auto 'test_group' {
        events = 'User',
        pattern = 'IdempotencyTest',
        command = function() first_called = true end,
      }
      auto 'test_group' {
        events = 'User',
        pattern = 'IdempotencyTest',
        command = function() second_called = true end,
      }
      vim.cmd('doautocmd User IdempotencyTest')
      assert.is_false(first_called)
      assert.is_true(second_called)
    end)
  end)

  describe('command as Vim string', function()
    it('should execute a Vim command string', function()
      vim.g.auto_test_vim_cmd = nil
      auto 'test_group' {
        events = 'User',
        pattern = 'VimCmdTest',
        command = 'let g:auto_test_vim_cmd = 42',
      }
      vim.cmd('doautocmd User VimCmdTest')
      assert.equal(42, vim.g.auto_test_vim_cmd)
      vim.g.auto_test_vim_cmd = nil
    end)
  end)
end)