"""
Tests for escape_code_fences_for_display.

B1: Escape triple-backtick markers inside reasoning text before wrapping
    in an outer ``` fence, so inner ``` doesn't break the outer block.
"""

import pytest
from gateway.stream_consumer import escape_code_fences_for_display


class TestEscapeCodeFencesForDisplay:
    """escape_code_fences_for_display prevents inner ``` from breaking
    the outer code block used to render reasoning."""

    def test_no_fence_passthrough(self):
        text = "plain reasoning text"
        assert escape_code_fences_for_display(text) == text

    def test_single_fence_escaped(self):
        text = "model used ```python\nx = 1\n``` in its thinking"
        result = escape_code_fences_for_display(text)
        assert "```" not in result
        assert "\\`\\`\\`" in result

    def test_multiple_fences_all_escaped(self):
        text = "```\nblock1\n``` and ```python\nblock2\n```"
        result = escape_code_fences_for_display(text)
        assert result.count("```") == 0
        assert result.count("\\`\\`\\`") == 4

    def test_empty_string(self):
        assert escape_code_fences_for_display("") == ""

    def test_none_returns_none(self):
        assert escape_code_fences_for_display(None) is None

    def test_integration_with_outer_fence(self):
        """Simulates the gateway's reasoning wrapping logic."""
        raw = "thinking about:\n```python\nprint('hi')\n```\nok"
        escaped = escape_code_fences_for_display(raw)
        wrapped = f"💭 **Reasoning:**\n```\n{escaped}\n```\n\nHere's the answer."
        # The outer ``` should not be broken by inner ```
        assert wrapped.count("```") == 2  # only outer open + close
        assert "\\`\\`\\`" in wrapped