local light_up = require 'std.light_up'

describe('std.light_up', function()
  local bufnr

  before_each(function()
    vim.api.nvim_buf_set_lines(0, 0, -1, true, {
      'foo bar baz',
      'test_word end_of_line',
      'keyword1 keyword2 middle',
    })
    bufnr = 0
  end)

  after_each(function()
    pcall(vim.api.nvim_buf_delete, 0, { force = true })
  end)

  describe('_.buffer', function()
    it('should highlight a word at start of line without preceding boundary', function()
      local words = { test_word = 'Title' }
      local ns = light_up.buffer(bufnr, words)
      local marks = vim.api.nvim_buf_get_extmarks(bufnr, ns, 0, -1, { details = true })
      assert.equal(1, #marks, 'should have exactly one highlight mark')
      assert.equal(1, marks[1][2], 'should be on line 1 (where test_word appears)')
      assert.equal(0, marks[1][3], 'test_word starts at column 0')
    end)

    it('should highlight multiple different words on the same line', function()
      local words = { keyword1 = 'Title', keyword2 = 'Comment' }
      local ns = light_up.buffer(bufnr, words)
      local marks = vim.api.nvim_buf_get_extmarks(bufnr, ns, 0, -1, { details = true })
      assert.equal(2, #marks, 'both keyword1 and keyword2 on same line should be highlighted')
    end)

    it('should highlight all instances of same word on same line', function()
      vim.api.nvim_buf_set_lines(0, 0, -1, true, { 'foo foo foo' })
      local words = { foo = 'Title' }
      local ns = light_up.buffer(bufnr, words)
      local marks = vim.api.nvim_buf_get_extmarks(bufnr, ns, 0, -1, { details = true })
      assert.equal(3, #marks, 'all three foo occurrences should be highlighted')
    end)
  end)

  describe('_.get_vim_highlight_groups', function()
    it('should return a non-empty table', function()
      local groups = light_up.get_vim_highlight_groups()
      assert.is_table(groups)
      assert(next(groups) ~= nil, 'should have at least one highlight group')
    end)

    it('should contain common highlight groups', function()
      local groups = light_up.get_vim_highlight_groups()
      assert.is_not_nil(groups['Title'])
      assert.is_not_nil(groups['Comment'])
      assert.is_not_nil(groups['Normal'])
    end)
  end)
end)