package com.zy.acs.manager.core.service.floyd;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.zy.acs.manager.common.exception.BusinessException;
import com.zy.acs.manager.manager.entity.Code;
import com.zy.acs.manager.manager.entity.CodeGap;
import com.zy.acs.manager.manager.entity.Route;
import com.zy.acs.manager.manager.service.CodeGapService;
import com.zy.acs.manager.manager.service.CodeService;
import com.zy.acs.manager.manager.service.RouteService;
import com.zy.acs.manager.system.service.ConfigService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

/**
 * Created by vincent on 2023/6/15
 */
@Slf4j
@Component
public class FloydNavigateService {

    public static final double INF = 999999.0;

    @Autowired
    private CodeService codeService;
    @Autowired
    private CodeGapService codeGapService;
    @Autowired
    private RouteService routeService;
    @Autowired
    private ConfigService configService;

    private List<Long> matrixHeader;
    private Double[][] adjacencyMatrix;
    private int[][] pathMatrix;
    private Double[][] floydMatrix;

    public List<Integer> calculatePath(Integer origin, Integer destination) {
        List<Integer> path = new ArrayList<>();

        path.add(destination);

        Integer current = destination;
        while (!current.equals(origin)) {
            current = this.pathMatrix[origin][current];
            path.add(current);
        }

        Collections.reverse(path);
        return path;
    }

    public int codeIdx(Long codeId) {
        return this.matrixHeader.indexOf(codeId);
    }

    public Long getCodeId(int idx) {
        return this.matrixHeader.get(idx);
    }

//    @PostConstruct
    @SuppressWarnings("all")
    public void generateMatrix() {
        log.info("【FLOYD】正在计算矩阵数据......");
        List<Code> codeList = codeService.list(new LambdaQueryWrapper<Code>().eq(Code::getStatus, 1).eq(Code::getDeleted, false));

        int size = codeList.size();

        matrixHeader = new ArrayList<>(size);
        adjacencyMatrix = new Double[size][size];
        pathMatrix = new int[size][size];

        for (int i = 0; i < size; i++) {
            Code startCode = codeList.get(i);
            matrixHeader.add(startCode.getId());
            for (int j = 0; j < size; j++) {
                Code endCode = codeList.get(j);
                Route route = routeService.findByCodeOfBoth(startCode.getId(), endCode.getId());
                CodeGap codeGap = codeGapService.findByCodeOfBoth(startCode.getId(), endCode.getId());

                double distance = INF;
                int path = -1;

                if (null != route && null != codeGap && codeGap.getDistance() > 0) {
                    if (i != j) {
                        distance = codeGap.getDistance();
                    }
                    path = i;
                }


                adjacencyMatrix[i][j] = distance;

                pathMatrix[i][j] = path;
            }
        }

        floydMatrix = this.floydAlgorithm(adjacencyMatrix);

    }

    /**
     * Floyd
     */
    @SuppressWarnings("all")
    private Double[][] floydAlgorithm(Double[][] graph) {
        int n = graph.length;
        Double[][] shortestPaths = new Double[n][n];

        for (int i = 0; i < n; i++) {
            for (int j = 0; j < n; j++) {
                shortestPaths[i][j] = graph[i][j];
            }
        }

        for (int k = 0; k < n; k++) {
            for (int i = 0; i < n; i++) {
                for (int j = 0; j < n; j++) {
                    if (shortestPaths[i][k] + shortestPaths[k][j] < shortestPaths[i][j]) {
                        shortestPaths[i][j] = shortestPaths[i][k] + shortestPaths[k][j];
                        pathMatrix[i][j] = pathMatrix[k][j];
                    }
                }
            }
        }

        return shortestPaths;
    }

    public Double[][] getAdjacencyMatrix() {
        if (null == adjacencyMatrix) {
            throw new BusinessException("核心算法还在进行中");
        }
        return adjacencyMatrix;
    }

    public int[][] getPathMatrix() {
        if (null == pathMatrix) {
            throw new BusinessException("核心算法还在进行中");
        }
        return pathMatrix;
    }

    public List<Long> getMatrixHeader() {
        if (null == matrixHeader) {
            throw new BusinessException("核心算法还在进行中");
        }
        return matrixHeader;
    }

    public Double[][] getFloydMatrix() {
        if (null == floydMatrix) {
            throw new BusinessException("核心算法还在进行中");
        }
        return floydMatrix;
    }
}