#pragma once

#include <map>
#include <optional>
#include <string>
#include <vector>

#include "Building.h"
#include "GameConfig.h"
#include "RecipesConfig.h"

// Production state of a building for the UI status light (REQ-UI-STATUS-LIGHT).
// The simulation owns the classification so it stays in sync with the
// production-cycle predicates (REQ-MAT-CYCLE); the UI maps each value to a fill
// color.
enum class ProductionStatus
{
    Unconfigured,  // no recipe/schematic selected (grey)
    Producing,     // a production cycle is active (green)
    Starved,       // idle: a required input is missing / Salvage Bay empty (red)
    Blocked,       // idle: output buffer full, inputs otherwise present (yellow)
};

// The rules deciding what a building can produce and whether it can start.
// Pure functions of the config and the building itself — they read no factory
// state, so they are free functions rather than BuildingSystem members.

// Recipes this building could run: every recipe of its type for an auto-recipe
// building (REQ-BLD-SMELTER, REQ-BLD-REPROCESSING), otherwise just its selected one.
std::vector<const RecipeDef*> gatherCandidateRecipes(const GameConfig& config,
                                                     const Building& b);

// True when the building's input buffer holds every ingredient the recipe needs.
bool recipeInputsAvailable(const Building& b, const RecipeDef& recipe);

// Total materials a shipyard needs for its schematic plus its placed modules
// (REQ-BLD-SHIPYARD), keyed by item id.
std::map<std::string, int> computeShipyardRequiredMaterials(const GameConfig& config,
                                                            const Building& b);

// True when a production cycle could start right now, ignoring output-buffer space.
bool hasInputsToStart(const GameConfig& config, const Building& b);

// Status light for a building, or nullopt for types that show none — belts,
// splitters, tunnels, HQ and defence stations (REQ-UI-STATUS-LIGHT).
std::optional<ProductionStatus> getProductionStatus(const GameConfig& config,
                                                    const Building& building);