45 Degree Angle from Last Low/High

//@version=4
study("45 Degree Angle from Last Low/High", overlay=true)

// Determine whether the last point was a high or low
lastHigh = highest(high, 500)
lastLow = lowest(low, 500)
lastPoint = bar_index - nz(max(lastLow, lastHigh))

// Calculate the slope of the line
slope = 1

// Calculate the y-intercept of the line
yIntercept = lastHigh - slope * (bar_index - lastPoint)

// Calculate the 45-degree angle line using the formula y = x
angleLine = bar_index - lastPoint

// Plot the angle line
plot(angleLine + yIntercept,
     color=color.new(color.green, 0),
     style=plot.style_line,
     show_last=1,
     linewidth=1,
     trackprice=true,
     transp=0)

// Extend the angle line into the future
futureAngleLine = angleLine + (bar_index - lastPoint) * 2 // Change the multiplier to adjust the length of the projected line

// Plot the future angle line
plot(futureAngleLine + yIntercept,
     color=color.new(color.yellow, 0),
     style=plot.style_line,
     show_last=1,
     linewidth=2,
     trackprice=true,
     transp=0)