Battle-for-Tismo/shared/game_state/sites.js

// Construction sites: the economic nodes a tile improvement is raised through.
//
// Ordering a tile improvement no longer pays for it and raises it at once.
// Instead the state hands the site a forecast budget and the tile becomes an
// economic node that first gathers the materials it needs -- buying them from
// the reachable stores at whatever the market currently asks -- and only then
// builds, drawing power from the grid as it goes. Leftover money stays with the
// improvement; a bill the site cannot cover is taken from the public treasury.
//
// A site stalls only when no supplier of a needed material is within reach;
// there is no daily budget rise any more, the work simply buys at the current
// market price. The owner may still cancel the work, losing everything already
// spent. Production buildings that finish become private agents and step
// through the same phases again when they upgrade.

import { key } from "../hex.js";
import { ECONOMY } from "../data/economy.js";
import { tileImprovementById, transportImprovement } from "../data/improvements.js";
import {
  tileImprovementResourceCost,
  constructionResourceCost,
} from "../resources.js";
import { TILE_IMPROVEMENT_HP, HOURS_PER_DAY } from "./constants.js";

const MATERIAL_IDS = ["steel", "hightech"];
const RESOURCE_IDS = ["steel", "hightech", "energy"];

function emptyResources() {
  return { steel: 0, hightech: 0, energy: 0 };
}

export const siteMethods = {
  // --------------------------------------------------------- lookup --

  constructionSiteAt(coords) {
    if (!this.constructionSites || !coords) return null;
    return this.constructionSites.get(key(coords.x, coords.y)) || null;
  },

  // Every construction site a nation owns, newest last, as plain objects.
  getConstructionSites(civ) {
    const result = [];
    if (!this.constructionSites) return result;
    for (const site of this.constructionSites.values()) {
      if (site.civ !== civ) continue;
      result.push(site);
    }
    return result;
  },

  // How much money an improvement holds after it was raised.
  improvementCashAt(coords) {
    if (!this.improvementCash || !coords) return 0;
    return this.improvementCash.get(key(coords.x, coords.y)) || 0;
  },

  // The delivered unit prices the site locked in when its work was decided.
  _lockedUnitPrices() {
    const prices = {};
    for (const id of RESOURCE_IDS) prices[id] = this._marketUnitCost(id);
    return prices;
  },

  // ------------------------------------------------- A* to a city --

  // The cheapest allied city to haul to, found with A* over the land network so
  // the route and the city agree. Roads and railways are cheaper to haul along,
  // which is why a city reachable by rail may beat a nearer one over open land.
  _siteCityPath(civ, coords) {
    const cities = this.cities.filter((city) => city.civ === civ);
    if (cities.length === 0) return { cityId: null, path: [] };
    const start = { x: coords.x, y: coords.y };
    const neighbours = (cell) => this._neighbours(cell);
    const canEnter = (cell) => {
      const tile = this.tiles[key(cell.x, cell.y)];
      return !!tile && tile.terrainClass === "Land";
    };
    const stepCost = (_from, to) => {
      const k = key(to.x, to.y);
      if (this.railways.has(k)) return 0.25;
      if (this.roads.has(k)) return 0.5;
      return 1;
    };
    const heuristic = (from, to) => this.topology.tileDistance(from, to);
    let bestCity = null;
    let bestPath = null;
    let bestCost = Infinity;
    for (const city of cities) {
      const path = this._pathfinder.findPath(
        start, city.coords, neighbours, canEnter, stepCost, heuristic
      );
      if (path.length === 0) continue;
      let cost = 0;
      for (let i = 1; i < path.length; i++) cost += stepCost(path[i - 1], path[i]);
      if (cost < bestCost) {
        bestCost = cost;
        bestCity = city;
        bestPath = path;
      }
    }
    if (!bestCity) return { cityId: null, path: [] };
    return { cityId: bestCity.id, path: bestPath.map((cell) => [cell.x, cell.y]) };
  },

  // ---------------------------------------------------- creation --

  // Opens a construction site on a tile. `money` is the forecast budget moved
  // out of the coffers (or a private agent's cash) into the node; the caller has
  // already reserved it. A `private` site belongs to a production agent: it keeps
  // `money` only as the forecast the panel shows, and every purchase is charged
  // to that agent's account (cash, then a central-bank loan) instead of the
  // treasury. `proto` is the improvement being raised and `level` the production
  // level a fresh build starts from (0) or the level an upgrade targets minus one.
  _openConstructionSite({
    civ, coords, proto, kind = "build", targetLevel = 0, money, buildCost, level = 0, isPrivate = false,
  }) {
    const k = key(coords.x, coords.y);
    const materials = kind === "upgrade"
      ? this.constructionResourceCost(proto, level, buildCost)
      : tileImprovementResourceCost(proto, buildCost);
    const needed = emptyResources();
    for (const id of RESOURCE_IDS) needed[id] = Math.max(0, materials[id] || 0);
    const gdp = this.getPlayerGdp(civ);
    const baseHours = ECONOMY.buildingHours(gdp, buildCost);
    const totalHours = Math.max(1, baseHours * this.constructionSpeedMultiplier(civ));
    const route = this._siteCityPath(civ, coords);
    const site = {
      coords: { x: coords.x, y: coords.y },
      id: proto.id,
      civ,
      kind,
      targetLevel,
      private: !!isPrivate,
      phase: "materials",
      budget: Math.max(0, money || 0),
      prices: this._lockedUnitPrices(),
      needed,
      bought: emptyResources(),
      elapsedHours: 0,
      totalHours,
      cityId: route.cityId,
      path: route.path,
      stalled: false,
      // Consecutive stalled days, driving the doubling budget rise.
      budgetRaises: 0,
      lastBuyDay: -1,
    };
    this.constructionSites.set(k, site);
    this._emitChanged();
    return site;
  },

  // Makes a site's first purchase at once, so an order feels immediate and the
  // day's gathering is not repeated on the next tick.
  _kickoffSite(site) {
    site.lastBuyDay = Math.floor(this.totalHours / HOURS_PER_DAY);
    if (site.phase === "materials") this._gatherSiteMaterials(site);
    else this._buySiteEnergy(site);
  },

  // Moves `amount` from a nation's treasury to a site's own account, filing the
  // expense under tile construction. Unlike a regular spend the money is not
  // handed to the regions yet: the site still has to buy with it.
  _reserveSiteBudget(civ, amount, category = "tilebuild") {
    if (!(amount > 0)) return 0;
    this.budgets.set(civ, this.getBudget(civ) - amount);
    this._recordBudgetCash(civ, category, -amount);
    return amount;
  },

  // The forecast a work is handed when it is decided: the build cost plus the
  // market value of the steel and high-tech it will buy. Electricity is a grid
  // draw billed as the build runs, so it is not part of the forecast.
  _siteForecastBudget(civ, proto, buildCost, kind = "build", level = 0) {
    const materials = kind === "upgrade"
      ? this.constructionResourceCost(proto, level, buildCost)
      : tileImprovementResourceCost(proto, buildCost);
    let total = buildCost;
    for (const id of MATERIAL_IDS) total += (materials[id] || 0) * this.getResourcePrice(id);
    return total;
  },

  // --------------------------------------------------- daily tick --

  // One hour of every site: the materials phase buys once a day, the
  // construction phase advances and buys the day's power.
  _tickConstructionSites() {
    if (!this.constructionSites || this.constructionSites.size === 0) return;
    const day = Math.floor(this.totalHours / HOURS_PER_DAY);
    for (const site of Array.from(this.constructionSites.values())) {
      const k = key(site.coords.x, site.coords.y);
      if (!this.constructionSites.has(k)) continue;
      if (site.phase === "materials") {
        if (site.lastBuyDay !== day) {
          site.lastBuyDay = day;
          this._gatherSiteMaterials(site);
          this._raiseSiteBudgetIfStalled(site);
        }
      } else {
        site.elapsedHours += 1;
        if (site.lastBuyDay !== day) {
          site.lastBuyDay = day;
          this._buySiteEnergy(site);
        }
        if (site.elapsedHours >= site.totalHours) this._completeConstructionSite(site);
      }
    }
  },

  // Tries to buy every material the site still needs at the current market
  // prices. A day that buys nothing while materials are still missing stalls the
  // work because no supplier is within reach.
  _gatherSiteMaterials(site) {
    // Keep the site's reported prices pointed at the live market rather than a
    // price frozen when the work was ordered.
    for (const id of RESOURCE_IDS) site.prices[id] = this._marketUnitCost(id);
    let boughtAnything = false;
    for (const id of MATERIAL_IDS) {
      const missing = site.needed[id] - site.bought[id];
      if (!(missing > 1e-9)) continue;
      const bought = this._siteBuy(site, id, missing);
      if (bought > 0) {
        site.bought[id] += bought;
        boughtAnything = true;
      }
    }
    const stillMissing = MATERIAL_IDS.some((id) => site.needed[id] - site.bought[id] > 1e-9);
    if (!stillMissing) {
      site.stalled = false;
      site.budgetRaises = 0;
      site.phase = "construction";
      site.elapsedHours = 0;
      this._emitChanged();
      return;
    }
    const stalled = !boughtAnything;
    if (site.stalled !== stalled) {
      site.stalled = stalled;
      this._emitChanged();
    }
    if (!stalled) site.budgetRaises = 0;
  },

  // A day that bought nothing while a supplier is within reach prices what is
  // still missing at the current market and moves the difference into the site's
  // account, then tries again. There is no daily percentage rise any more: the
  // site simply buys at whatever the market currently asks. When no supplier can
  // reach the site at any price the top-up cannot help, so it is left alone. A
  // private site raises its own agent's account instead of the treasury: the
  // money is borrowed, not subsidised.
  _raiseSiteBudgetIfStalled(site) {
    if (!site.stalled || site.phase !== "materials") return;
    if (this._siteUnreachableMaterials(site).length > 0) return;
    for (const id of RESOURCE_IDS) site.prices[id] = this._marketUnitCost(id);
    const add = this._siteTopUp(site, site.prices);
    if (!(add > 0)) return;
    if (!site.private) this._reserveSiteBudget(site.civ, add);
    site.budget += add;
    this._gatherSiteMaterials(site);
    this._emitChanged();
  },

  // Buys `amount` of one resource for the site: first from the allied city the
  // route hauls to, then from the reachable stores, paying from the site's own
  // budget first and the public treasury after. The site does not hold out for a
  // locked price -- it buys at whatever the cheapest reachable supplier asks.
  _siteBuy(site, id, amount) {
    if (!(amount > 1e-9)) return 0;
    if (!site.cityId) return 0;
    const city = this._cityById.get(site.cityId);
    if (!city) return 0;
    const payer = this._sitePayer(site);
    const paidBefore = payer.total;
    let bought = 0;
    // The hub city already holds some of the material; the state buys it from
    // the region at the market value before reaching further afield.
    const store = this.getCityResourceStock(city);
    const take = Math.min(store[id] || 0, amount);
    if (take > 0) {
      store[id] -= take;
      this._payRegionForMaterial(city, id, take, payer);
      bought += take;
    }
    const remaining = amount - bought;
    if (remaining > 1e-9) {
      const nodes = this._resourceNodes();
      const temp = emptyResources();
      const allowSea = this._cityMarketAccess(city);
      this._procureFromNeighbours(city, id, remaining, temp, nodes, {
        payer,
        allowSea,
        maxUnitCost: Infinity,
      });
      bought += temp[id] || 0;
    }
    // File the purchase under tile construction with its quantity, so the
    // budget panel can show how many units were bought and at what price. A
    // private work is not a public expense, so it is left out of the budget.
    if (bought > 0 && !site.private) {
      const proto = tileImprovementById(site.id) || transportImprovement(site.id);
      this._recordBudgetCategoryResource(
        site.civ, "tilebuild", id, payer.total - paidBefore, proto ? proto.name : site.id, bought
      );
    }
    return bought;
  },

  // The day's power a site under construction draws, bought the same way.
  _buySiteEnergy(site) {
    const missing = site.needed.energy - site.bought.energy;
    if (!(missing > 1e-9)) return 0;
    const perDay = Math.min(
      missing,
      (site.needed.energy / Math.max(site.totalHours, 1)) * HOURS_PER_DAY
    );
    const bought = this._siteBuy(site, "energy", perDay);
    if (bought > 0) site.bought.energy += bought;
    return bought;
  },

  // A payer that empties the site's own account first, then draws on the
  // nation's treasury, so an overrun is public money. A private site instead
  // draws on its production agent: that agent's cash first, then a central-bank
  // loan, so a producer is never subsidised by the state.
  _sitePayer(site) {
    const payer = { total: 0, overflow: 0 };
    if (site.private) {
      const k = key(site.coords.x, site.coords.y);
      payer.charge = (cost) => {
        if (!(cost > 0)) return;
        this._chargeBuildingAccount(k, cost);
        payer.total += cost;
      };
      return payer;
    }
    payer.charge = (cost) => {
      if (!(cost > 0)) return;
      const fromBudget = Math.min(site.budget, cost);
      site.budget -= fromBudget;
      const rest = cost - fromBudget;
      if (rest > 0) {
        this.budgets.set(site.civ, this.getBudget(site.civ) - rest);
        this._recordBudgetCash(site.civ, "tilebuild", -rest);
        payer.overflow += rest;
      }
      payer.total += cost;
    };
    return payer;
  },

  // ------------------------------------------------ city building orders --

  // One day of a queued city building's material phase. Like a construction
  // site it buys whatever of its steel and high-tech bill it still lacks, at the
  // prices locked in when the order was placed: the nation's own stores first,
  // then the reachable suppliers. It only flips to construction once the whole
  // bill is gathered; a day that buys nothing leaves it stalled.
  _gatherBuildEntry(city, entry) {
    const payer = this._entryPayer(city, entry);
    const remaining = { steel: 0, hightech: 0 };
    for (const id of MATERIAL_IDS) {
      remaining[id] = Math.max(0, (entry.needed[id] || 0) - (entry.bought[id] || 0));
    }
    // The nation's own cities are bought from first, nearest to the building.
    const drawn = this._drawFromNearest(city.civ, city.coords, remaining, payer);
    for (const id of MATERIAL_IDS) {
      if (drawn[id] > 0) entry.bought[id] = (entry.bought[id] || 0) + drawn[id];
    }
    for (const id of MATERIAL_IDS) {
      const missing = (entry.needed[id] || 0) - (entry.bought[id] || 0);
      if (!(missing > 1e-9)) continue;
      const temp = emptyResources();
      this._procureFromNeighbours(city, id, missing, temp, this._resourceNodes(), {
        payer,
        allowSea: this._cityMarketAccess(city),
      });
      if (temp[id] > 0) entry.bought[id] = (entry.bought[id] || 0) + temp[id];
    }
    const stillMissing = MATERIAL_IDS.some(
      (id) => (entry.needed[id] || 0) - (entry.bought[id] || 0) > 1e-9
    );
    if (!stillMissing) entry.phase = "construction";
    entry.stalled = stillMissing;
    return !stillMissing;
  },

  // A payer for a queued building: its reserved material budget first, then the
  // public treasury, so an overrun is public money.
  _entryPayer(city, entry) {
    const payer = { total: 0, overflow: 0 };
    payer.charge = (cost) => {
      if (!(cost > 0)) return;
      const fromBudget = Math.min(entry.budget || 0, cost);
      entry.budget = (entry.budget || 0) - fromBudget;
      const rest = cost - fromBudget;
      if (rest > 0) {
        this.budgets.set(city.civ, this.getBudget(city.civ) - rest);
        this._recordBudgetCash(city.civ, "construction", -rest);
        payer.overflow += rest;
      }
      payer.total += cost;
    };
    return payer;
  },

  // Hands a finished order's unspent material budget back to the treasury. The
  // reserved money was never paid to the regions, so it is not clawed back.
  _releaseEntryBudget(civ, entry) {
    if (!(entry.budget > 0)) return;
    this.budgets.set(civ, this.getBudget(civ) + entry.budget);
    this._recordBudgetCash(civ, entry.budgetCategory || "construction", entry.budget);
    entry.budget = 0;
  },

  // -------------------------------------------------- completion --

  _completeConstructionSite(site) {
    const k = key(site.coords.x, site.coords.y);
    if (this.constructionSites.get(k) !== site) return;
    const civ = site.civ;
    const proto = tileImprovementById(site.id) || transportImprovement(site.id);
    if (!proto || this.civAt(site.coords) !== civ) {
      this.constructionSites.delete(k);
      return;
    }
    if (site.kind === "upgrade") {
      const agent = this._ensureBuildingAgent(k);
      agent.level = site.targetLevel;
      agent.upgrading = null;
      // A private upgrade borrowed as it spent, so there is no unspent public
      // budget to hand back.
      if (!site.private) agent.cash = (agent.cash || 0) + site.budget;
      this._clearTileGdpCache();
      this._touchModifiers();
      this._tileImprovementVersion += 1;
    } else if (transportImprovement(site.id)) {
      this.roads.delete(k);
      this.railways.delete(k);
      if (site.id === "railway") this.railways.add(k);
      else this.roads.add(k);
      this._improvementVersion += 1;
      if (site.budget > 0) {
        this.improvementCash.set(k, (this.improvementCash.get(k) || 0) + site.budget);
      }
    } else {
      this.tileImprovements.set(k, site.id);
      this.tileImprovementOwner.set(k, civ);
      this.tileImprovementHp.set(k, TILE_IMPROVEMENT_HP[site.id] || 1000);
      if (this._isProductionAgent(proto)) {
        const agent = this._ensureBuildingAgent(k);
        // A public work hands its unspent budget to the new private owner as
        // working capital; a private one already borrowed for itself.
        if (!site.private) agent.cash = (agent.cash || 0) + site.budget;
      } else if (site.budget > 0) {
        this.improvementCash.set(k, (this.improvementCash.get(k) || 0) + site.budget);
      }
      this._tileImprovementVersion += 1;
      this._visibilityDirty = true;
    }
    this.constructionSites.delete(k);
    this._dropTileGdpCache(k);
    this._emitChanged();
  },

  // ------------------------------------------------- owner actions --

  // The materials a site still needs that no reachable source can provide: the
  // hub city's own store is empty and no supplier sits within the trade radius.
  // A non-empty result means no budget, however large, can unstall the work, so
  // the panel keeps a lasting warning instead.
  _siteUnreachableMaterials(site) {
    const missing = MATERIAL_IDS.filter(
      (id) => site.needed[id] - site.bought[id] > 1e-9
    );
    if (missing.length === 0) return [];
    const city = site.cityId != null ? this._cityById.get(site.cityId) : null;
    if (!city) return missing.slice();
    const nodes = this._resourceNodes();
    const allowSea = this._cityMarketAccess(city);
    const store = this.getCityResourceStock(city);
    const unreachable = [];
    for (const id of missing) {
      if ((store[id] || 0) > 0) continue;
      if (this._nearbySuppliers(city, id, nodes, allowSea).length > 0) continue;
      unreachable.push(id);
    }
    return unreachable;
  },

  // The extra a site must be granted to buy its remaining materials at the given
  // unit prices (its own budgeted prices by default): the shortfall between what
  // those materials cost and the money the site still holds.
  _siteTopUp(site, prices = null) {
    const p = prices || site.prices;
    let wanted = 0;
    for (const id of RESOURCE_IDS) {
      const missing = Math.max(0, site.needed[id] - site.bought[id]);
      wanted += missing * p[id];
    }
    return Math.max(0, wanted - site.budget);
  },

  // Cancels a site. Nothing is refunded: the budget already handed to it and
  // whatever materials it gathered are lost.
  requestCancelSite(civ, coords) {
    const site = this.constructionSiteAt(coords);
    if (!site || site.civ !== civ) return false;
    this.constructionSites.delete(key(site.coords.x, site.coords.y));
    this._emitChanged();
    return true;
  },
};