instrument {
    name = 'Liquid FVG LSMA - BRYAN IN$IDER',
    icon = 'indicators:BelkhayateTiming',
    overlay = true
}

lookback_break = input(20, "Lookback topo/fundo", input.integer)
fvg_lookback   = input(10, "Lookback FVG", input.integer)
use_fvg        = input(true, "Usar FVG", input.boolean)
use_gap        = input(true, "Usar gap interno", input.boolean)
lsma_period    = input(9, "Perodo LSMA (Open)", input.integer)
prox_pct       = input(0.05, "Proximidade (%) para pr-sinal", input.double)

arrow_up_color   = input { default = "#00FF6A", type = input.color }
arrow_down_color = input { default = "#FF3B30", type = input.color }

-- Funes auxiliares
local function highest_in_range(src, len, start_shift)
    local maxv = src[start_shift]
    for i = start_shift, start_shift + len - 1 do
        if src[i] and src[i] > maxv then maxv = src[i] end
    end
    return maxv
end
local function lowest_in_range(src, len, start_shift)
    local minv = src[start_shift]
    for i = start_shift, start_shift + len - 1 do
        if src[i] and src[i] < minv then minv = src[i] end
    end
    return minv
end
local function fvg_up_at(i) return low[i] and high[i+2] and (low[i] > high[i+2]) end
local function fvg_down_at(i) return high[i] and low[i+2] and (high[i] < low[i+2]) end
local function fvg_up_recent(w) for i=1,w do if fvg_up_at(i) then return true end end return false end
local function fvg_down_recent(w) for i=1,w do if fvg_down_at(i) then return true end end return false end
local function gap_up_now() return open[0] and close[1] and (open[0] > close[1]) end
local function gap_down_now() return open[0] and close[1] and (open[0] < close[1]) end

-- LSMA
local function lsma(src, period, shift)
    if not src[shift] then return nil end
    local sumX,sumY,sumXY,sumX2=0,0,0,0
    for i=0,period-1 do
        if not src[i+shift] then return nil end
        sumX=sumX+(i+1)
        sumY=sumY+src[i+shift]
        sumXY=sumXY+(i+1)*src[i+shift]
        sumX2=sumX2+(i+1)*(i+1)
    end
    local slope=(period*sumXY - sumX*sumY)/(period*sumX2 - sumX*sumX)
    local intercept=(sumY - slope*sumX)/period
    return slope*period + intercept
end
lsma_val = lsma(open, lsma_period, 0)

-- Lgica
local recent_high = highest_in_range(high, lookback_break, 1)
local recent_low  = lowest_in_range(low,  lookback_break, 1)

local dist_top = (recent_high - open[0]) / recent_high
local dist_bot = (open[0] - recent_low) / recent_low

local cond_up = dist_top <= prox_pct and (not use_fvg or fvg_up_recent(fvg_lookback)) and (not use_gap or gap_up_now())
local cond_dn = dist_bot <= prox_pct and (not use_fvg or fvg_down_recent(fvg_lookback)) and (not use_gap or gap_down_now())

local break_up   = high[0] and (high[0] > recent_high)
local break_down = low[0]  and (low[0]  < recent_low)

plot_shape(cond_up and break_up, 'Buy', shape_style.arrowup, shape_size.normal, arrow_up_color, shape_location.belowbar)
plot_shape(cond_dn and break_down, 'Sell', shape_style.arrowdown, shape_size.normal, arrow_down_color, shape_location.abovebar)

if lsma_val then plot(lsma_val, "LSMA Open", "orange", 2) end