alpha

// This source code is subject to the terms of the Mozilla Public License 2.0 at https://mozilla.org/MPL/2.0/
// © nautilusalpha

//@version=5
indicator(title='alpha', shorttitle='Killzones', overlay=true)

//ASIA
asiashow = input(true, title='Display Asia Range', group="Asia Session")
asiacolor = input(color.new(color.aqua, 70), 'Asia Range Color', group="Asia Session")
asia = input.session(title='Asia Session', defval='1900-0000', group="Asia Session")


// FUNCTIONS
in_session(sess) =>
    not na(time(timeframe.period, sess))

start_time(sess) =>
    int startTime = na
    startTime := in_session(sess) and not in_session(sess)[1] ? time : startTime[1]
    startTime

is_new_session(res, sess) =>
    t = time(res, sess)
    na(t[1]) and not na(t) or t[1] < t

BarInSession(sess) =>
    time(timeframe.period, sess) != 0

_hline(StartTime, EndTime, Price, Color, Style, Width) =>
    return_1 = line.new(StartTime, Price, EndTime, Price, xloc=xloc.bar_time, extend=extend.none, color=Color, style=Style, width=Width)

//PARAMS
indexHighTF = barstate.isrealtime ? 0 : 0
indexCurrTF = barstate.isrealtime ? 0 : 0
dailyhigh = request.security(syminfo.tickerid, 'D', high, lookahead=barmerge.lookahead_on)[indexHighTF]
dailylow = request.security(syminfo.tickerid, 'D', low[indexCurrTF], lookahead=barmerge.lookahead_on)[indexCurrTF]


//ASIA BOX
asia_session = is_new_session('1440', asia)

float _asialow = na
float _asiahigh = na
_asiabox = box(na)

_asiastart = start_time(asia)
_asialow := asia_session ? low : in_session(asia) ? math.min(low, _asialow[1]) : na
_asiahigh := asia_session ? high : in_session(asia) ? math.max(high, _asiahigh[1]) : na
diff = _asiahigh[1] - _asialow[1]

if in_session(asia)
    if in_session(asia)[1]
        box.delete(_asiabox[1])

    if low < _asialow
        _asialow := low
        _asialow
    if high > _asiahigh
        _asiahigh := high
        _asiahigh

    if asiashow
        _asiabox := box.new(_asiastart, _asiahigh, time, _asialow, xloc=xloc.bar_time, bgcolor=asiacolor, border_color=asiacolor, border_style=line.style_solid)
        _asiabox
//LONDON
londonshow = input(true, title='Display London session', group="London Session")
londoncolor = input(color.new(#28db46, 70), 'London Session Color', group="London Session")
london = input.session(title='London Session', defval='0200-0500', group="London Session")



//LONDON BOX
london_session = is_new_session('1440', london)

float _londonlow = na
float _londonhigh = na
_londonbox = box(na)

_londonstart = start_time(london)
_londonlow := london_session ? low : in_session(london) ? math.min(low, _londonlow[1]) : na
_londonhigh := london_session ? high : in_session(london) ? math.max(high, _londonhigh[1]) : na

if in_session(london)
    if in_session(london)[1]
        box.delete(_londonbox[1])

    if low < _londonlow
        _londonlow := low
        _londonlow
    if high > _londonhigh
        _londonhigh := high
        _londonhigh

    if londonshow
        _londonbox := box.new(_londonstart, _londonhigh, time, _londonlow, xloc=xloc.bar_time, bgcolor=londoncolor, border_color=londoncolor, border_style=line.style_solid)
        _londonbox
//NEW YORK
newyorkshow = input(true, title='Display London session', group="London Session")
newyorkcolor = input(color.new(#e02c2c, 70), 'New York Session Color', group="New York Session")
newyork = input.session(title='New York Session', defval='0700-1000', group="New York Session")



//NEW YORK BOX
newyork_session = is_new_session('1440', newyork)

float _newyorklow = na
float _newyorkhigh = na
_newyorkbox = box(na)

_newyorkstart = start_time(newyork)
_newyorklow := newyork_session ? low : in_session(newyork) ? math.min(low, _newyorklow[1]) : na
_newyorkhigh := newyork_session ? high : in_session(newyork) ? math.max(high, _newyorkhigh[1]) : na

if in_session(newyork)
    if in_session(newyork)[1]
        box.delete(_newyorkbox[1])

    if low < _newyorklow
        _newyorklow := low
        _newyorklow
    if high > _newyorkhigh
        _newyorkhigh := high
        _newyorkhigh

    if newyorkshow
        _newyorkbox := box.new(_newyorkstart, _newyorkhigh, time, _newyorklow, xloc=xloc.bar_time, bgcolor=newyorkcolor, border_color=newyorkcolor, border_style=line.style_solid)
        _newyorkbox