Nifty on Thursday ended 97 points higher to form a bullish engulfing candlestick pattern, which indicates a short-term bottom reversal for the index.The index is currently placed at the edge of breaking above the immediate hurdle of 21,850 level and a decisive move above this resistance is likely to pull Nifty towards 22,000-22,100 levels in the short term. Immediate support is at 21,720 level.