#pragma once

#include <vector>

#include "entt/entity/entity.hpp"

#include "BuildingId.h"
#include "SelectionContext.h"

class QWidget;
class SelectionContent;
class Simulation;

// What is currently selected, in the selection panel's terms. The two categories are
// mutually exclusive (REQ-UI-SELECTION-CATEGORIES): either buildings is non-empty, or
// actors and/or debris are, never both.
struct SelectionRequest
{
    std::vector<BuildingId>   buildings;
    std::vector<entt::entity> actors;
    std::vector<entt::entity> debris;

    bool isEmpty() const
    {
        return buildings.empty() && actors.empty() && debris.empty();
    }
};

// One entry of the content catalog (REQ-UI-SELECTION-CONTENT). Selections that share an
// entry get the same content and differ only in the name and symbol in the header.
enum class SelectionContentKind
{
    None,              // nothing selected: the panel hides itself entirely
    RecipeProduction,  // Miner, Assembler, Smelter, Reprocessing Plant
    Shipyard,
    Storage,           // Salvage Bay
    Hq,
    Belt,              // Belt, Tunnel Entry, Tunnel Exit
    Splitter,
    MultiBuilding,
    Ship,
    Station,
    Debris,
    FieldMulti,
};

// Identifies the card on screen. The panel rebuilds when this changes and only refreshes
// otherwise, so a construction site finishing swaps the card while a progress counter
// running does not.
struct ContentKey
{
    SelectionContentKind kind   = SelectionContentKind::None;
    bool                 isSite = false;

    bool operator==(const ContentKey& other) const
    {
        return kind == other.kind && isSite == other.isSite;
    }
    bool operator!=(const ContentKey& other) const { return !(*this == other); }
};

// The card this selection calls for. This is where REQ-UI-SELECTION-AGGREGATE is
// decided: a multi-selection that aggregates resolves to the single-object kind, and
// everything else to one of the two count summaries.
ContentKey chooseContent(const SelectionRequest& request, Simulation& sim);

// Builds the card. Returns nullptr for SelectionContentKind::None.
SelectionContent* createContent(const ContentKey& key, const SelectionRequest& request,
                                const SelectionContext& context, QWidget* parent);