import type { ShipSnapshot, SpatialNodeSnapshot, SystemSnapshot } from "./contracts";
import type {
  CameraMode,
  OrbitalAnchor,
  Selectable,
  SelectionGroup,
  WorldState,
} from "./viewerTypes";
import { formatGalaxyDistance } from "./viewerMath";

export function describeSelectable(world: WorldState | undefined, item: Selectable): string {
  if (!world) {
    return item.kind;
  }
  if (item.kind === "ship") {
    return world.ships.get(item.id)?.label ?? item.id;
  }
  if (item.kind === "station") {
    return world.stations.get(item.id)?.label ?? item.id;
  }
  if (item.kind === "node") {
    return item.id;
  }
  if (item.kind === "spatial-node") {
    return `${world.spatialNodes.get(item.id)?.kind ?? "node"} ${item.id}`;
  }
  if (item.kind === "bubble") {
    return `bubble ${item.id}`;
  }
  if (item.kind === "claim") {
    return `claim ${item.id}`;
  }
  if (item.kind === "construction-site") {
    return `construction ${item.id}`;
  }
  if (item.kind === "planet") {
    return world.systems.get(item.systemId)?.planets[item.planetIndex]?.label ?? `${item.systemId}:${item.planetIndex}`;
  }
  return world.systems.get(item.id)?.label ?? item.id;
}

export function describeHoverLabel(world: WorldState | undefined, item: Selectable): string | undefined {
  if (!world) {
    return undefined;
  }

  if (item.kind === "ship") {
    return world.ships.get(item.id)?.label ?? item.id;
  }

  if (item.kind === "station") {
    return world.stations.get(item.id)?.label ?? item.id;
  }

  if (item.kind === "system") {
    return world.systems.get(item.id)?.label ?? item.id;
  }

  if (item.kind === "planet") {
    const system = world.systems.get(item.systemId);
    const planet = system?.planets[item.planetIndex];
    return planet ? `${system?.label ?? item.systemId} / ${planet.label}` : `${item.systemId} / planet ${item.planetIndex + 1}`;
  }

  if (item.kind === "node") {
    const node = world.nodes.get(item.id);
    if (!node) {
      return item.id;
    }

    const anchorPath = node.anchorNodeId
      ? describeSpatialNodePathWithinSystem(world, node.systemId, node.anchorNodeId)
      : undefined;
    return anchorPath ? `${anchorPath} / ${node.itemId}` : `${node.systemId} / ${node.itemId}`;
  }

  if (item.kind === "spatial-node") {
    const node = world.spatialNodes.get(item.id);
    if (!node) {
      return item.id;
    }

    if (node.kind === "star") {
      const system = world.systems.get(node.systemId);
      return system ? `${system.label} star` : `${node.systemId} star`;
    }

    return describeSpatialNodePathWithinSystem(world, node.systemId, node.id) ?? `${node.systemId} / ${node.kind}`;
  }

  if (item.kind === "bubble") {
    const bubble = world.localBubbles.get(item.id);
    const anchorPath = bubble?.nodeId
      ? describeSpatialNodePathWithinSystem(world, bubble.systemId, bubble.nodeId)
      : undefined;
    return anchorPath ? `${anchorPath} bubble` : `Bubble ${item.id}`;
  }

  if (item.kind === "claim") {
    const claim = world.claims.get(item.id);
    const anchorPath = claim?.nodeId
      ? describeSpatialNodePathWithinSystem(world, claim.systemId, claim.nodeId)
      : undefined;
    return anchorPath ? `${anchorPath} claim` : `Claim ${item.id}`;
  }

  if (item.kind === "construction-site") {
    const site = world.constructionSites.get(item.id);
    const anchorPath = site?.nodeId
      ? describeSpatialNodePathWithinSystem(world, site.systemId, site.nodeId)
      : undefined;
    const siteLabel = site ? (site.blueprintId ?? site.targetDefinitionId) : item.id;
    return anchorPath ? `${anchorPath} / ${siteLabel}` : `Construction ${siteLabel}`;
  }

  return describeSelectable(world, item);
}

export function getSelectionGroup(item: Selectable): SelectionGroup {
  if (item.kind === "ship") {
    return "ships";
  }
  if (
    item.kind === "station"
    || item.kind === "node"
    || item.kind === "spatial-node"
    || item.kind === "bubble"
    || item.kind === "claim"
    || item.kind === "construction-site"
  ) {
    return "structures";
  }
  return "celestials";
}

export function resolveSelectableSystemId(world: WorldState | undefined, selection: Selectable): string | undefined {
  if (!world) {
    return undefined;
  }

  if (selection.kind === "ship") {
    return world.ships.get(selection.id)?.systemId;
  }
  if (selection.kind === "station") {
    return world.stations.get(selection.id)?.systemId;
  }
  if (selection.kind === "node") {
    return world.nodes.get(selection.id)?.systemId;
  }
  if (selection.kind === "spatial-node") {
    return world.spatialNodes.get(selection.id)?.systemId;
  }
  if (selection.kind === "bubble") {
    return world.localBubbles.get(selection.id)?.systemId;
  }
  if (selection.kind === "claim") {
    return world.claims.get(selection.id)?.systemId;
  }
  if (selection.kind === "construction-site") {
    return world.constructionSites.get(selection.id)?.systemId;
  }
  if (selection.kind === "planet") {
    return selection.systemId;
  }
  return selection.id;
}

export function resolveFocusedBubbleId(world: WorldState | undefined, selectedItems: Selectable[]): string | undefined {
  if (!world || selectedItems.length !== 1) {
    return undefined;
  }

  const selected = selectedItems[0];
  if (selected.kind === "bubble") {
    return selected.id;
  }
  if (selected.kind === "ship") {
    return world.ships.get(selected.id)?.bubbleId ?? world.ships.get(selected.id)?.spatialState.currentBubbleId ?? undefined;
  }
  if (selected.kind === "station") {
    return world.stations.get(selected.id)?.bubbleId ?? undefined;
  }
  if (selected.kind === "spatial-node") {
    return world.spatialNodes.get(selected.id)?.bubbleId ?? undefined;
  }
  if (selected.kind === "claim") {
    return world.claims.get(selected.id)?.bubbleId ?? undefined;
  }
  if (selected.kind === "construction-site") {
    return world.constructionSites.get(selected.id)?.bubbleId ?? undefined;
  }
  return undefined;
}

export function describeOrbitalParent(world: WorldState | undefined, systemId?: string, anchor?: OrbitalAnchor): string {
  if (!world || !systemId) {
    return "unknown";
  }

  const system = world.systems.get(systemId);
  if (!system) {
    return systemId;
  }

  if (!anchor || anchor.kind === "star") {
    return `${system.label} star`;
  }

  const planet = system.planets[anchor.planetIndex];
  if (!planet) {
    return `${system.label} star`;
  }

  if (anchor.kind === "planet") {
    return planet.label;
  }

  return `${planet.label} moon ${anchor.moonIndex + 1}`;
}

export function renderSystemDetails(
  world: WorldState | undefined,
  system: SystemSnapshot,
  activeContext: boolean,
  cameraMode: CameraMode,
  cameraTargetShipId?: string,
): string {
  if (!world) {
    return "";
  }

  let shipCount = 0;
  let stationCount = 0;
  let nodeCount = 0;
  let spatialNodeCount = 0;
  let bubbleCount = 0;
  let claimCount = 0;
  let constructionCount = 0;
  let moonCount = 0;

  for (const ship of world.ships.values()) {
    if (ship.systemId === system.id) {
      shipCount += 1;
    }
  }
  for (const station of world.stations.values()) {
    if (station.systemId === system.id) {
      stationCount += 1;
    }
  }
  for (const node of world.nodes.values()) {
    if (node.systemId === system.id) {
      nodeCount += 1;
    }
  }
  for (const node of world.spatialNodes.values()) {
    if (node.systemId === system.id) {
      spatialNodeCount += 1;
    }
  }
  for (const bubble of world.localBubbles.values()) {
    if (bubble.systemId === system.id) {
      bubbleCount += 1;
    }
  }
  for (const claim of world.claims.values()) {
    if (claim.systemId === system.id) {
      claimCount += 1;
    }
  }
  for (const site of world.constructionSites.values()) {
    if (site.systemId === system.id) {
      constructionCount += 1;
    }
  }
  for (const planet of system.planets) {
    moonCount += planet.moonCount;
  }

  const followText = activeContext && cameraMode === "follow" && cameraTargetShipId
    ? `<p>Camera locked to ${world.ships.get(cameraTargetShipId)?.label ?? cameraTargetShipId}</p>`
    : "";

  return `
    <p>${system.id}${activeContext ? " · active system" : ""}</p>
    <p>${system.starKind} · ${system.starCount} star${system.starCount > 1 ? "s" : ""}</p>
    <p>Planets ${system.planets.length}<br>Moons ${moonCount}<br>Ships ${shipCount}<br>Stations ${stationCount}</p>
    <p>Spatial nodes ${spatialNodeCount}<br>Resource nodes ${nodeCount}<br>Bubbles ${bubbleCount}</p>
    <p>Claims ${claimCount}<br>Construction sites ${constructionCount}</p>
    <p>Height ${formatGalaxyDistance(system.galaxyPosition.y)}</p>
    <p>${system.planets.slice(0, 8).map((planet) => `${planet.label} (${planet.planetType})`).join("<br>")}</p>
    ${followText}
  `;
}

export function describeShipState(world: WorldState | undefined, ship: ShipSnapshot): string {
  const baseState = ship.state;
  if (baseState === "capacitor-starved") {
    return `${baseState} while ${describeControllerTask(ship.controllerTaskKind)}`;
  }

  if (!world || (baseState !== "ftl" && baseState !== "spooling-ftl" && baseState !== "warping" && baseState !== "spooling-warp")) {
    return baseState;
  }

  const destinationNodeId = ship.spatialState.destinationNodeId ?? ship.spatialState.transit?.destinationNodeId;
  if (!destinationNodeId) {
    return baseState;
  }

  const destinationNode = world.spatialNodes.get(destinationNodeId);
  if (!destinationNode) {
    return `${baseState} -> ${destinationNodeId}`;
  }

  if (baseState === "warping" || baseState === "spooling-warp") {
    const destinationPath = describeSpatialNodePathWithinSystem(world, destinationNode.systemId, destinationNodeId);
    return `${baseState} -> ${destinationPath ?? destinationNodeId}`;
  }

  const destinationSystem = world.systems.get(destinationNode.systemId);
  return `${baseState} -> ${destinationSystem?.label ?? destinationNode.systemId}`;
}

function describeControllerTask(taskKind: string): string {
  switch (taskKind) {
    case "travel":
      return "travel";
    case "extract":
      return "mining";
    case "dock":
      return "docking";
    case "unload":
      return "transfer";
    case "refuel":
      return "refuel";
    case "deliver-construction":
      return "material delivery";
    case "build-construction-site":
      return "site construction";
    case "construct-module":
      return "module construction";
    case "undock":
      return "undocking";
    case "load-workers":
      return "worker loading";
    case "unload-workers":
      return "worker unloading";
    default:
      return taskKind;
  }
}

export function describeShipCurrentAction(ship: ShipSnapshot): { label: string; progress: number } | undefined {
  if (!ship.currentAction) {
    return undefined;
  }

  return {
    label: ship.currentAction.label,
    progress: Math.max(0, Math.min(ship.currentAction.progress, 1)),
  };
}

export function describeShipLocation(world: WorldState | undefined, ship: ShipSnapshot): { system: string; local?: string } {
  const systemId = ship.spatialState.currentSystemId || ship.systemId;
  const system = world?.systems.get(systemId);
  const systemLabel = system?.label ?? systemId;
  if (!world || !system) {
    return { system: systemLabel };
  }

  if (ship.dockedStationId) {
    const station = world.stations.get(ship.dockedStationId);
    if (station) {
      const anchorPath = station.anchorNodeId
        ? describeSpatialNodePathWithinSystem(world, station.systemId, station.anchorNodeId)
        : undefined;
      return {
        system: systemLabel,
        local: anchorPath ? `${anchorPath}/${station.label}` : station.label,
      };
    }
  }

  const currentNodeId = ship.spatialState.currentNodeId ?? ship.nodeId;
  if (currentNodeId) {
    const nodePath = describeSpatialNodePathWithinSystem(world, systemId, currentNodeId);
    if (nodePath) {
      return { system: systemLabel, local: nodePath };
    }
  }

  const currentBubbleId = ship.spatialState.currentBubbleId ?? ship.bubbleId;
  if (currentBubbleId) {
    const bubble = world.localBubbles.get(currentBubbleId);
    if (bubble?.nodeId) {
      const nodePath = describeSpatialNodePathWithinSystem(world, systemId, bubble.nodeId);
      if (nodePath) {
        return { system: systemLabel, local: nodePath };
      }
    }
  }

  return { system: systemLabel };
}

export function describeActiveSpace(
  world: WorldState | undefined,
  zoomLevel: "local" | "system" | "universe",
  activeSystemId: string | undefined,
  selectedItems: Selectable[],
): string {
  if (!world || zoomLevel === "universe") {
    return "deep-space";
  }

  const activeSystem = activeSystemId ? world.systems.get(activeSystemId) : undefined;
  if (!activeSystem) {
    return "deep-space";
  }

  if (zoomLevel !== "local") {
    return activeSystem.label;
  }

  const bubbleId = resolveFocusedBubbleId(world, selectedItems);
  if (bubbleId) {
    const bubble = world.localBubbles.get(bubbleId);
    const localPath = bubble?.nodeId
      ? describeSpatialNodePathWithinSystem(world, activeSystem.id, bubble.nodeId)
      : undefined;
    return localPath
      ? `${activeSystem.label} / ${localPath}`
      : activeSystem.label;
  }

  const selected = selectedItems.length === 1 ? selectedItems[0] : undefined;
  if (selected?.kind === "planet" && selected.systemId === activeSystem.id) {
    const planet = activeSystem.planets[selected.planetIndex];
    return planet
      ? `${activeSystem.label} / ${planet.label}`
      : activeSystem.label;
  }

  return activeSystem.label;
}

export function describeSpatialNodePathWithinSystem(world: WorldState, systemId: string, nodeId: string): string | undefined {
  const node = world.spatialNodes.get(nodeId);
  const system = world.systems.get(systemId);
  if (!node || !system) {
    return undefined;
  }

  if (node.parentNodeId) {
    const parentPath = describeSpatialNodePathWithinSystem(world, systemId, node.parentNodeId);
    const segment = describeSpatialNodeSegment(world, system, node);
    return parentPath ? `${parentPath}/${segment}` : segment;
  }

  if (node.kind === "star") {
    return undefined;
  }

  return describeSpatialNodeSegment(world, system, node);
}

function describeSpatialNodeSegment(world: WorldState, system: SystemSnapshot, node: SpatialNodeSnapshot): string {
  const moonMatch = node.id.match(/-planet-(\d+)-moon-(\d+)$/);
  if (moonMatch) {
    const moonIndex = Number.parseInt(moonMatch[2], 10);
    return `Moon ${moonIndex}`;
  }

  const lagrangeMatch = node.id.match(/-planet-\d+-(l[1-5])$/);
  if (lagrangeMatch) {
    return lagrangeMatch[1].toUpperCase();
  }

  const planetMatch = node.id.match(/-planet-(\d+)$/);
  if (planetMatch) {
    const planetIndex = Number.parseInt(planetMatch[1], 10) - 1;
    return system.planets[planetIndex]?.label ?? `Planet ${planetMatch[1]}`;
  }

  if (node.kind === "station" && node.occupyingStructureId) {
    return world.stations.get(node.occupyingStructureId)?.label ?? node.occupyingStructureId;
  }

  if (node.kind === "resource-site") {
    return node.orbitReferenceId ?? "Resource Site";
  }

  return node.orbitReferenceId ?? node.kind;
}