# Waste management #

volatileSolid <- function(GE, Dig){
  # equação original:   VS <- (GE * (1 - DE%/100) + (UE * GE)) * ((1 - ASH)/18.45) # IPCC 10.24
  # manipulando, temos: VS <- (GE/18.45 * (1 - Dig/100) + (UE * GE)/18.45) * ((1 - ASH))
  # e finalmente:       VS <- (DMI * (1 - Dig/100) + (UE * GE)/18.45) * (1 - ASH)
  # VS <- (FI * (1 - Dig/100) + (0.02/18.45)) * (1 - 0.08) # kg VS / animal / day IPCC 10.24
  VS <- (GE * (1 - Dig/100) + 0.02) * ((1 - 0.08)/18.45) # kg VS / animal / day  IPCC 10.24
  
  return(mean(VS))
}

# Wasting management total emission (Mg CH4)
# EF: vector of "fator de emissão para a população de animais definida" (g CH4)
# N: vector of "número de cabeças por espécie animal (por categoria T no país)"
wasteTotalEmission <- function(EF, N){
  CH4emission <- (EF * N) / 1e+3    # Mg CH4 / year

  return(CH4emission)
} 

# B0 (kg CH4 / VS)
# MCF (%)
# MS (%)
# [EF] = VS * kg CH4/VS = kg CH4
emissionFactor <- function(VS, B0, MCF, MS){
  EF <- VS * 365 * B0 * 0.67 * MCF/100 * MS  # kg CH4 / year IPCC 10..23
  
  return(EF)
}

# Excreção anual de N por animais do rebanho #
# Nrate: taxa diária de excreção de N (kg N / kg animal mass / day)
# LW: média dos pesos vivos de cada categoria (kg)
NExcretion <- function(Nrate, LW){
  Nex <- (Nrate * LW / 1000) * 365  # kg N / animal / year
    
  return(Nex)
}

# Emissões diretas de N2O pelo manejo de dejetos #
# Nex : kg N / animal / year
# EF: Fator de emissão direta de N (kg N2O-N / kg N)
directN2OEmissions <- function(N, Nex, MS, EF){
  N2Od <- (N * Nex * MS) * EF * (44 / 28)  # kg N2O / year
  N2Od <- N2Od / 1e+3                             # Mg N2O / year
  
  return(N2Od)
}

# Estimativa do N volatilizado com o manejo de dejetos #
# Nex : kg N / animal / year
# N: números de animais por categoria
volatilizationN <- function(N, Nex, MS, Frac){
  Nvol <- (N * Nex * MS) * Frac/100  # kg N / year
  
  return(Nvol)
}

# Emissões indiretas de N2O pela reposição do N volatilizado do manejo de dejetos # 
# EF: Fator de emissão indireta de N (kg N2O-N / (kg NH3-N + NOx-N volatilised)) (IPCC 2006)
# Nvol: N volatilizado (kg N / year)
indirectN2OEmissions <- function(Nvol, EF){
  N2Oi <- (Nvol * EF) * 44 / 28   # kg N2O / year
  N2Oi <- N2Oi / 1e+3             # Mg N2O / year
  
  return(N2Oi)
}

herdWasteManagement <- function(allInp, 
                                allHerdStructure){
  
  resList <- list()
  
  for(hd in c("Equilibrium", "Current")){
    
    allMS  <- allInp$MS[,allInp$climateRegion]
    allMCF <- allInp$MCF[,allInp$climateRegion]
    
    catEmissions <- lapply(names(allInp$Category), function(nm){
        N  <- allHerdStructure[allHerdStructure$Category == nm, hd]
        
        if(N != 0){
          
          dietNames <- unique(unlist(allInp$Category[[nm]][allInp$mthnames]))
          Dig <- unname(sapply(dietNames, function(d) as.numeric(allInp$Diet[[d]]["Dig"])))
          LWG <- unname(sapply(dietNames, function(d) as.numeric(allInp$Diet[[d]]["LWG.Ref"])))
          
          manageType <- allInp$Category[[nm]][["wastingManageType"]]
          LW     <- allInp$averageLW[[nm]]
          MS     <- allMS[[manageType]]
          MCF    <- allMCF[[manageType]]
          EFN2Od <- allInp$EFN2Od[[manageType]]
          Frac   <- allInp$Frac[[manageType]]
          GE     <- GECalc(LW = LW, Dig = Dig, LWG = LWG, catnb = nm, N = N, allInp = allInp) 
          VS     <- volatileSolid(GE = GE, Dig = Dig)
          Nex    <- NExcretion(Nrate = allInp$Nrate, LW = LW)
          Nvol   <- volatilizationN(N = N, Nex = Nex, MS = MS, Frac = Frac)
          EFCH4  <- emissionFactor(VS = VS, B0 = allInp$B0, MCF = MCF, MS = MS)
          CH4    <- wasteTotalEmission(EF = EFCH4, N = N)
          dN2O   <- directN2OEmissions(N = N, Nex = Nex, MS = MS, EF = EFN2Od)
          iN2O   <- indirectN2OEmissions(Nvol = Nvol, EF = allInp$EFN2Oi)
          
          resDF <- data.frame(Category             = nm,
                              wasteManageType      = manageType,
                              NExcretion           = Nex,
                              volatileSolid        = VS,
                              volatilizedN         = Nvol,
                              emissionFactor       = EFCH4,
                              CH4emission          = CH4,
                              directN2OEmissions   = dN2O,
                              indirectN2OEmissions = iN2O)
        }else{
          resDF <- data.frame(Category             = nm,
                              wasteManageType      = "-",
                              NExcretion           = 0,
                              volatileSolid        = 0,
                              volatilizedN         = 0,
                              emissionFactor       = 0,
                              CH4emission          = 0,
                              directN2OEmissions   = 0,
                              indirectN2OEmissions = 0)
        }
        
        return(resDF)
      }
    )
    
    resList[[hd]] <- do.call(rbind, catEmissions)
  }

  return(resList)
}