import React, {
  useEffect,
  useMemo,
  useState,
  useCallback,
  useRef,
} from "react";
import { useSimulationPaths } from "../../../store/store";
import * as THREE from "three";
import { useThree } from "@react-three/fiber";
import {
  ConveyorEventsSchema,
  VehicleEventsSchema,
} from "../../../types/world/worldTypes";

// Type definitions
export interface PointAction {
  uuid: string;
  name: string;
  type: string;
  material: string;
  delay: number | string;
  spawnInterval: string | number;
  isUsed: boolean;
}

export interface PathPoint {
  uuid: string;
  position: [number, number, number];
  actions: PointAction[];
  connections: {
    targets: Array<{ pathUUID: string }>;
  };
}

export interface SimulationPath {
  modeluuid: string;
  points: PathPoint[];
  pathPosition: [number, number, number];
  speed?: number;
}

export interface Process {
  id: string;
  paths: SimulationPath[];
  animationPath: THREE.Vector3[];
  pointActions: PointAction[][];
  speed: number;
}

interface ProcessCreatorProps {
  onProcessesCreated: (processes: Process[]) => void;
}

// Convert event schemas to SimulationPath
function convertToSimulationPath(
  path: ConveyorEventsSchema | VehicleEventsSchema
): SimulationPath {
  const { modeluuid } = path;

  // Simplified normalizeAction function that preserves exact original properties
  const normalizeAction = (action: any): PointAction => {
    return { ...action }; // Return exact copy with no modifications
  };

  if (path.type === "Conveyor") {
    return {
      modeluuid,
      points: path.points.map((point) => ({
        uuid: point.uuid,
        position: point.position,
        actions: point.actions.map(normalizeAction), // Preserve exact actions
        connections: {
          targets: point.connections.targets.map((target) => ({
            pathUUID: target.pathUUID,
          })),
        },
      })),
      pathPosition: path.position,
      speed:
        typeof path.speed === "string"
          ? parseFloat(path.speed) || 1
          : path.speed || 1,
    };
  } else {
    return {
      modeluuid,
      points: [
        {
          uuid: path.point.uuid,
          position: path.point.position,
          actions: Array.isArray(path.point.actions)
            ? path.point.actions.map(normalizeAction)
            : [normalizeAction(path.point.actions)],
          connections: {
            targets: path.point.connections.targets.map((target) => ({
              pathUUID: target.pathUUID,
            })),
          },
        },
      ],
      pathPosition: path.position,
      speed: path.point.speed || 1,
    };
  }
}

// Custom shallow comparison for arrays
const areArraysEqual = (a: any[], b: any[]) => {
  if (a.length !== b.length) return false;
  for (let i = 0; i < a.length; i++) {
    if (a[i] !== b[i]) return false;
  }
  return true;
};

// Helper function to create an empty process
const createEmptyProcess = (): Process => ({
  id: `process-${Math.random().toString(36).substring(2, 11)}`,
  paths: [],
  animationPath: [],
  pointActions: [],
  speed: 1,
});

// Enhanced connection checking function
function shouldReverseNextPath(
  currentPath: SimulationPath,
  nextPath: SimulationPath
): boolean {
  if (nextPath.points.length !== 3) return false;

  const currentLastPoint = currentPath.points[currentPath.points.length - 1];
  const nextFirstPoint = nextPath.points[0];
  const nextLastPoint = nextPath.points[nextPath.points.length - 1];

  // Check if current last connects to next last (requires reversal)
  const connectsToLast = currentLastPoint.connections.targets.some(
    (target) =>
      target.pathUUID === nextPath.modeluuid &&
      nextLastPoint.connections.targets.some(
        (t) => t.pathUUID === currentPath.modeluuid
      )
  );

  // Check if current last connects to next first (no reversal needed)
  const connectsToFirst = currentLastPoint.connections.targets.some(
    (target) =>
      target.pathUUID === nextPath.modeluuid &&
      nextFirstPoint.connections.targets.some(
        (t) => t.pathUUID === currentPath.modeluuid
      )
  );

  // Only reverse if connected to last point and not to first point
  return connectsToLast && !connectsToFirst;
}

// Updated path adjustment function
function adjustPathPointsOrder(paths: SimulationPath[]): SimulationPath[] {
  if (paths.length < 2) return paths;

  const adjustedPaths = [...paths];

  for (let i = 0; i < adjustedPaths.length - 1; i++) {
    const currentPath = adjustedPaths[i];
    const nextPath = adjustedPaths[i + 1];

    if (shouldReverseNextPath(currentPath, nextPath)) {
      const reversedPoints = [
        nextPath.points[2],
        nextPath.points[1],
        nextPath.points[0],
      ];

      adjustedPaths[i + 1] = {
        ...nextPath,
        points: reversedPoints,
      };
    }
  }

  return adjustedPaths;
}

// Main hook for process creation
export function useProcessCreation() {
  const { scene } = useThree();
  const [processes, setProcesses] = useState<Process[]>([]);

  const hasSpawnAction = useCallback((path: SimulationPath): boolean => {
    return path.points.some((point) =>
      point.actions.some((action) => action.type.toLowerCase() === "spawn")
    );
  }, []);

  const createProcess = useCallback(
    (paths: SimulationPath[]): Process => {
      if (!paths || paths.length === 0) {
        return createEmptyProcess();
      }

      const animationPath: THREE.Vector3[] = [];
      const pointActions: PointAction[][] = [];
      const processSpeed = paths[0]?.speed || 1;

      for (const path of paths) {
        for (const point of path.points) {
          const obj = scene.getObjectByProperty("uuid", point.uuid);
          if (!obj) {
            console.warn(`Object with UUID ${point.uuid} not found in scene`);
            continue;
          }

          const position = obj.getWorldPosition(new THREE.Vector3());
          animationPath.push(position.clone());
          pointActions.push(point.actions);
        }
      }

      return {
        id: `process-${Math.random().toString(36).substring(2, 11)}`,
        paths,
        animationPath,
        pointActions,
        speed: processSpeed,
      };
    },
    [scene]
  );

  const getAllConnectedPaths = useCallback(
    (
      initialPath: SimulationPath,
      allPaths: SimulationPath[],
      visited: Set<string> = new Set()
    ): SimulationPath[] => {
      const connectedPaths: SimulationPath[] = [];
      const queue: SimulationPath[] = [initialPath];
      visited.add(initialPath.modeluuid);

      const pathMap = new Map<string, SimulationPath>();
      allPaths.forEach((path) => pathMap.set(path.modeluuid, path));

      while (queue.length > 0) {
        const currentPath = queue.shift()!;
        connectedPaths.push(currentPath);

        // Process outgoing connections
        for (const point of currentPath.points) {
          for (const target of point.connections.targets) {
            if (!visited.has(target.pathUUID)) {
              const targetPath = pathMap.get(target.pathUUID);
              if (targetPath) {
                visited.add(target.pathUUID);
                queue.push(targetPath);
              }
            }
          }
        }

        // Process incoming connections
        for (const [uuid, path] of pathMap) {
          if (!visited.has(uuid)) {
            const hasConnectionToCurrent = path.points.some((point) =>
              point.connections.targets.some(
                (t) => t.pathUUID === currentPath.modeluuid
              )
            );
            if (hasConnectionToCurrent) {
              visited.add(uuid);
              queue.push(path);
            }
          }
        }
      }

      return connectedPaths;
    },
    []
  );

  const createProcessesFromPaths = useCallback(
    (paths: SimulationPath[]): Process[] => {
      if (!paths || paths.length === 0) return [];

      const visited = new Set<string>();
      const processes: Process[] = [];
      const pathMap = new Map<string, SimulationPath>();
      paths.forEach((path) => pathMap.set(path.modeluuid, path));

      for (const path of paths) {
        if (!visited.has(path.modeluuid) && hasSpawnAction(path)) {
          const connectedPaths = getAllConnectedPaths(path, paths, visited);
          const adjustedPaths = adjustPathPointsOrder(connectedPaths);
          const process = createProcess(adjustedPaths);
          processes.push(process);
        }
      }

      return processes;
    },
    [createProcess, getAllConnectedPaths, hasSpawnAction]
  );

  return {
    processes,
    createProcessesFromPaths,
    setProcesses,
  };
}

const ProcessCreator: React.FC<ProcessCreatorProps> = React.memo(
  ({ onProcessesCreated }) => {
    const { simulationPaths } = useSimulationPaths();
    const { createProcessesFromPaths } = useProcessCreation();
    const prevPathsRef = useRef<SimulationPath[]>([]);
    const prevProcessesRef = useRef<Process[]>([]);

    const convertedPaths = useMemo((): SimulationPath[] => {
      if (!simulationPaths) return [];
      return simulationPaths.map((path) =>
        convertToSimulationPath(
          path as ConveyorEventsSchema | VehicleEventsSchema
        )
      );
    }, [simulationPaths]);

    const pathsDependency = useMemo(() => {
      if (!convertedPaths) return null;
      return convertedPaths.map((path) => ({
        id: path.modeluuid,
        hasSpawn: path.points.some((p: PathPoint) =>
          p.actions.some((a: PointAction) => a.type.toLowerCase() === "spawn")
        ),
        connections: path.points
          .flatMap((p: PathPoint) =>
            p.connections.targets.map((t: { pathUUID: string }) => t.pathUUID)
          )
          .join(","),
      }));
    }, [convertedPaths]);

    useEffect(() => {
      if (!convertedPaths || convertedPaths.length === 0) {
        if (prevProcessesRef.current.length > 0) {
          onProcessesCreated([]);
          prevProcessesRef.current = [];
        }
        return;
      }

      if (areArraysEqual(prevPathsRef.current, convertedPaths)) {
        return;
      }

      prevPathsRef.current = convertedPaths;
      const newProcesses = createProcessesFromPaths(convertedPaths);

      // console.log("--- Action Types in Paths ---");
      // convertedPaths.forEach((path) => {
      //   path.points.forEach((point) => {
      //     point.actions.forEach((action) => {
      //       console.log(
      //         `Path ${path.modeluuid}, Point ${point.uuid}: ${action.type}`
      //       );
      //     });
      //   });
      // });
      // console.log("New processes:", newProcesses);

      if (
        newProcesses.length !== prevProcessesRef.current.length ||
        !newProcesses.every(
          (proc, i) =>
            proc.paths.length === prevProcessesRef.current[i]?.paths.length &&
            proc.paths.every(
              (path, j) =>
                path.modeluuid ===
                prevProcessesRef.current[i]?.paths[j]?.modeluuid
            )
        )
      ) {
        onProcessesCreated(newProcesses);
        // prevProcessesRef.current = newProcesses;
      }
    }, [
      pathsDependency,
      onProcessesCreated,
      convertedPaths,
      createProcessesFromPaths,
    ]);

    return null;
  }
);

export default ProcessCreator;