Dynamic Anchored VWAP

// This source code is subject to the terms of the Mozilla Public License 2.0 at https://mozilla.org/MPL/2.0/
// Based on script of © LonesomeTheBlue
// Trend Lines for RSI, CCI, Momentum, OBV and MACD
// By ezPappi
//@version=6
indicator("Dynamic Anchored VWAP", shorttitle="DAVWAP", overlay=true)

// Automatic anchor time options
anchor_type = input.string("Chart Start", title="Anchor Type", 
                          options=["Chart Start", "Daily Start", "Weekly Start", "Monthly Start", "Manual"])
manual_anchor = input.time(timestamp("2017-12-18 00:00"), title="Manual Anchor Time")

// Get the first bar time of the chart
var first_bar_time = time

// Function to get automatic anchor time
get_anchor_time() =>
    switch anchor_type
        "Chart Start" => 
            // Use the first bar of the chart
            first_bar_time
        "Daily Start" => 
            // Start of current day
            timestamp(year(time), month(time), dayofmonth(time), 0, 0)
        "Weekly Start" => 
            // Start of current week (Monday)
            week_start = time - (dayofweek(time) - 2) * 24 * 60 * 60 * 1000
            timestamp(year(week_start), month(week_start), dayofmonth(week_start), 0, 0)
        "Monthly Start" => 
            // Start of current month
            timestamp(year(time), month(time), 1, 0, 0)
        => manual_anchor

anchor_time = get_anchor_time()

// Display options
show_labels = input.bool(true, title="Show Labels")
show_bands = input.bool(true, title="Show Standard Deviation Bands")

// Standard deviation multipliers
sd1_mult = input.float(1.0, title="1st SD Multiplier", minval=0.1, step=0.1)
sd2_mult = input.float(2.0, title="2nd SD Multiplier", minval=0.1, step=0.1)
sd3_mult = input.float(3.0, title="3rd SD Multiplier", minval=0.1, step=0.1)

// Colors
vwap_color = input.color(color.rgb(155, 139, 0), title="VWAP Color")
upper_color = input.color(color.lime, title="Upper Bands Color")
lower_color = input.color(color.red, title="Lower Bands Color")

// Check if we're at or after anchor time
is_anchor_start = time >= anchor_time and time[1] < anchor_time
is_after_anchor = time >= anchor_time

// Initialize variables
var float sum_pv = 0.0
var float sum_v = 0.0
var int bar_count = 0
var float sum_price = 0.0
var float sum_squared_diff = 0.0

// Calculate VWAP and standard deviation
if is_anchor_start
    // Reset at anchor start
    sum_pv := hlc3 * volume
    sum_v := volume
    bar_count := 1
    sum_price := hlc3
    sum_squared_diff := 0.0
else if is_after_anchor
    // Accumulate values
    sum_pv += hlc3 * volume
    sum_v += volume
    bar_count += 1
    sum_price += hlc3

// Calculate VWAP
vwap = is_after_anchor ? sum_pv / sum_v : na

// Calculate standard deviation
mean_price = is_after_anchor ? sum_price / bar_count : na

// Initialize band variables
var float sd1_upper = na
var float sd1_lower = na
var float sd2_upper = na
var float sd2_lower = na
var float sd3_upper = na
var float sd3_lower = na

if is_after_anchor and bar_count > 1
    sum_squared_diff += math.pow(hlc3 - mean_price, 2)
    variance = sum_squared_diff / (bar_count - 1)
    std_dev = math.sqrt(variance)
    
    // Calculate bands
    sd1_upper := vwap + (std_dev * sd1_mult)
    sd1_lower := vwap - (std_dev * sd1_mult)
    sd2_upper := vwap + (std_dev * sd2_mult)
    sd2_lower := vwap - (std_dev * sd2_mult)
    sd3_upper := vwap + (std_dev * sd3_mult)
    sd3_lower := vwap - (std_dev * sd3_mult)

// Plot bands (in global scope)
plot(show_bands and is_after_anchor ? sd1_upper : na, color=upper_color, linewidth=1, title="1st SD Upper")
plot(show_bands and is_after_anchor ? sd1_lower : na, color=lower_color, linewidth=1, title="1st SD Lower")
plot(show_bands and is_after_anchor ? sd2_upper : na, color=upper_color, linewidth=1, title="2nd SD Upper")
plot(show_bands and is_after_anchor ? sd2_lower : na, color=lower_color, linewidth=1, title="2nd SD Lower")
plot(show_bands and is_after_anchor ? sd3_upper : na, color=upper_color, linewidth=1, title="3rd SD Upper")
plot(show_bands and is_after_anchor ? sd3_lower : na, color=lower_color, linewidth=1, title="3rd SD Lower")

// Plot VWAP
plot(vwap, color=vwap_color, linewidth=2, title="Anchored VWAP")

// Add labels with price values
if show_labels and is_after_anchor and barstate.islast
    // VWAP label with price
    label.new(bar_index, vwap, "AVWAP: " + str.tostring(vwap, "#.##"), 
              color=vwap_color, 
              textcolor=color.white, 
              style=label.style_label_left,
              size=size.small)
    
    // Standard deviation band labels with prices
    if show_bands and not na(sd1_upper)
        label.new(bar_index, sd1_upper, "+" + str.tostring(sd1_mult) + "σ: " + str.tostring(sd1_upper, "#.##"), 
                  color=upper_color, 
                  textcolor=color.white, 
                  style=label.style_label_left,
                  size=size.small)
        
        label.new(bar_index, sd1_lower, "-" + str.tostring(sd1_mult) + "σ: " + str.tostring(sd1_lower, "#.##"), 
                  color=lower_color, 
                  textcolor=color.white, 
                  style=label.style_label_left,
                  size=size.small)
        
        label.new(bar_index, sd2_upper, "+" + str.tostring(sd2_mult) + "σ: " + str.tostring(sd2_upper, "#.##"), 
                  color=upper_color, 
                  textcolor=color.white, 
                  style=label.style_label_left,
                  size=size.small)
        
        label.new(bar_index, sd2_lower, "-" + str.tostring(sd2_mult) + "σ: " + str.tostring(sd2_lower, "#.##"), 
                  color=lower_color, 
                  textcolor=color.white, 
                  style=label.style_label_left,
                  size=size.small)

// Background highlight for anchor bar
bgcolor(is_anchor_start ? color.new(color.blue, 90) : na, title="Anchor Start")