# RELOG: Reverse Logistics Optimization
# Copyright (C) 2020, UChicago Argonne, LLC. All rights reserved.
# Released under the modified BSD license. See COPYING.md for more details.

using DataStructures
using JSON
using JSONSchema
using Printf
using Statistics

function parsefile(path::String)::Instance
    return RELOG.parse(JSON.parsefile(path))
end

function parse(json)::Instance
    basedir = dirname(@__FILE__)
    json_schema = JSON.parsefile("$basedir/../schemas/input.json")
    validate(json, Schema(json_schema))

    T = json["parameters"]["time horizon (years)"]
    json_schema["definitions"]["TimeSeries"]["minItems"] = T
    json_schema["definitions"]["TimeSeries"]["maxItems"] = T
    validate(json, Schema(json_schema))

    building_period = [1]
    if "building period (years)" in keys(json["parameters"])
        building_period = json["parameters"]["building period (years)"]
    end

    distance_metric = EuclideanDistance()
    if "distance metric" in keys(json["parameters"])
        metric_name = json["parameters"]["distance metric"]
        if metric_name == "driving"
            distance_metric = KnnDrivingDistance()
        elseif metric_name == "Euclidean"
            # nop
        else
            error("Unknown distance metric: $metric_name")
        end
    end

    plants = Plant[]
    products = Product[]
    collection_centers = CollectionCenter[]
    prod_name_to_product = Dict{String,Product}()

    # Create products
    for (product_name, product_dict) in json["products"]
        cost = product_dict["transportation cost (\$/km/tonne)"]
        energy = zeros(T)
        emissions = Dict()
        disposal_limit = zeros(T)
        disposal_cost = zeros(T)
        acquisition_cost = zeros(T)

        if "transportation energy (J/km/tonne)" in keys(product_dict)
            energy = product_dict["transportation energy (J/km/tonne)"]
        end

        if "transportation emissions (tonne/km/tonne)" in keys(product_dict)
            emissions = product_dict["transportation emissions (tonne/km/tonne)"]
        end

        if "disposal limit (tonne)" in keys(product_dict)
            disposal_limit = product_dict["disposal limit (tonne)"]
        end

        if "disposal cost (\$/tonne)" in keys(product_dict)
            disposal_cost = product_dict["disposal cost (\$/tonne)"]
        end

        if "acquisition cost (\$/tonne)" in keys(product_dict)
            acquisition_cost = product_dict["acquisition cost (\$/tonne)"]
        end

        prod_centers = []

        product = Product(
            acquisition_cost = acquisition_cost,
            collection_centers = prod_centers,
            disposal_cost = disposal_cost,
            disposal_limit = disposal_limit,
            name = product_name,
            transportation_cost = cost,
            transportation_emissions = emissions,
            transportation_energy = energy,
        )
        push!(products, product)
        prod_name_to_product[product_name] = product

        # Create collection centers
        if "initial amounts" in keys(product_dict)
            for (center_name, center_dict) in product_dict["initial amounts"]
                if "location" in keys(center_dict)
                    region = geodb_query(center_dict["location"])
                    center_dict["latitude (deg)"] = region.centroid.lat
                    center_dict["longitude (deg)"] = region.centroid.lon
                end
                center = CollectionCenter(
                    amount = center_dict["amount (tonne)"],
                    index = length(collection_centers) + 1,
                    latitude = center_dict["latitude (deg)"],
                    longitude = center_dict["longitude (deg)"],
                    name = center_name,
                    product = product,
                )
                push!(prod_centers, center)
                push!(collection_centers, center)
            end
        end
    end

    # Create plants
    for (plant_name, plant_dict) in json["plants"]
        input = prod_name_to_product[plant_dict["input"]]
        output = Dict()

        # Plant outputs
        if "outputs (tonne/tonne)" in keys(plant_dict)
            output = Dict(
                prod_name_to_product[key] => value for
                (key, value) in plant_dict["outputs (tonne/tonne)"] if value > 0
            )
        end

        energy = zeros(T)
        emissions = Dict()

        if "energy (GJ/tonne)" in keys(plant_dict)
            energy = plant_dict["energy (GJ/tonne)"]
        end

        if "emissions (tonne/tonne)" in keys(plant_dict)
            emissions = plant_dict["emissions (tonne/tonne)"]
        end

        for (location_name, location_dict) in plant_dict["locations"]
            sizes = PlantSize[]
            disposal_limit = Dict(p => [0.0 for t = 1:T] for p in keys(output))
            disposal_cost = Dict(p => [0.0 for t = 1:T] for p in keys(output))

            # GeoDB
            if "location" in keys(location_dict)
                region = geodb_query(location_dict["location"])
                location_dict["latitude (deg)"] = region.centroid.lat
                location_dict["longitude (deg)"] = region.centroid.lon
            end

            # Disposal
            if "disposal" in keys(location_dict)
                for (product_name, disposal_dict) in location_dict["disposal"]
                    limit = [1e8 for t = 1:T]
                    if "limit (tonne)" in keys(disposal_dict)
                        limit = disposal_dict["limit (tonne)"]
                    end
                    disposal_limit[prod_name_to_product[product_name]] = limit
                    disposal_cost[prod_name_to_product[product_name]] =
                        disposal_dict["cost (\$/tonne)"]
                end
            end

            # Capacities
            for (capacity_name, capacity_dict) in location_dict["capacities (tonne)"]
                push!(
                    sizes,
                    PlantSize(
                        capacity = Base.parse(Float64, capacity_name),
                        fixed_operating_cost = capacity_dict["fixed operating cost (\$)"],
                        opening_cost = capacity_dict["opening cost (\$)"],
                        variable_operating_cost = capacity_dict["variable operating cost (\$/tonne)"],
                    ),
                )
            end
            length(sizes) > 1 || push!(sizes, deepcopy(sizes[1]))
            sort!(sizes, by = x -> x.capacity)

            # Initial capacity
            initial_capacity = 0
            if "initial capacity (tonne)" in keys(location_dict)
                initial_capacity = location_dict["initial capacity (tonne)"]
            end

            # Storage
            storage_limit = 0
            storage_cost = zeros(T)
            if "storage" in keys(location_dict)
                storage_dict = location_dict["storage"]
                storage_limit = storage_dict["limit (tonne)"]
                storage_cost = storage_dict["cost (\$/tonne)"]
            end

            # Validation: Capacities
            if length(sizes) != 2
                throw("At most two capacities are supported")
            end
            if sizes[1].variable_operating_cost != sizes[2].variable_operating_cost
                throw("Variable operating costs must be the same for all capacities")
            end

            plant = Plant(
                disposal_cost = disposal_cost,
                disposal_limit = disposal_limit,
                emissions = emissions,
                energy = energy,
                index = length(plants) + 1,
                initial_capacity = initial_capacity,
                input = input,
                latitude = location_dict["latitude (deg)"],
                location_name = location_name,
                longitude = location_dict["longitude (deg)"],
                output = output,
                plant_name = plant_name,
                sizes = sizes,
                storage_cost = storage_cost,
                storage_limit = storage_limit,
            )

            push!(plants, plant)
        end
    end

    @info @sprintf("%12d collection centers", length(collection_centers))
    @info @sprintf("%12d candidate plant locations", length(plants))

    return Instance(
        time = T,
        products = products,
        collection_centers = collection_centers,
        plants = plants,
        building_period = building_period,
        distance_metric = distance_metric,
    )
end