using Aurora.Api;
using System;
using System.Collections.Generic;

namespace VisionCommon {
    /// <summary>
    /// 패턴 유틸 클래스
    /// </summary>
    public static class PatternUtil {
        private static Logger _logger = new Logger(typeof(PatternUtil).Name);

        /// <summary>
        /// UI 콤보 박스용 패턴 설명 생성
        /// </summary>
        /// <param name="patternInfo">패턴 정보</param>
        /// <returns>패턴 설명</returns>
        public static string GetPatternDescription(PatternInfo patternInfo) {
            var patternSymbol = "";
            if (patternInfo is FovPatternInfo) {
                patternSymbol = "[FP]";     // Fov Pattern
            }
            else {
                patternSymbol = "[CP]";     // Cam Pattern
            }
            return $"{patternSymbol}_{patternInfo.GetPatternId()}_{patternInfo.PatternType}_{patternInfo.Description}";
        }

        /// <summary>
        /// 패턴 검출 결과의 레퍼런스 인덱스를 구한다.
        /// </summary>
        /// <typeparam name="T">포인트 타입, 예)ImagePoint, StaticPoint</typeparam>
        /// <param name="measurePoints">패턴 검출 결과</param>
        /// <param name="referencePoints">레퍼런스</param>
        /// <param name="distanceTolerance">허용 거리(Spec)</param>
        /// <returns>패턴의 레퍼런스 인덱스 (성공 : 0 ~ , 실패 : -1)</returns>
        public static List<int> GetNearestPointIndex<T>(
            List<T> measurePoints,
            List<T> referencePoints,
            double distanceTolerance) where T : DoublePoint {
            var results = new List<int>();

            // 1. 파라미터 체크
            if (measurePoints == null || measurePoints.Count == 0) {
                _logger.FuncE("measurePoints : null or empty");
                return results;
            }

            if (referencePoints == null || referencePoints.Count == 0) {
                _logger.FuncE("referencePoints : null or empty");
                return results;
            }

            // 2. 모든 조합의 measure-reference point의 거리를 구한다.
            double[,] distanceMap = new double[measurePoints.Count, referencePoints.Count];

            // Row (j) : measure point
            for (int j = 0; j < measurePoints.Count; j++) {
                // Col (i) : reference point
                for (int i = 0; i < referencePoints.Count; i++) {
                    distanceMap[j, i] = MathUtil.CalculateDistance(
                        measurePoints[j],
                        referencePoints[i]);
                }
            }

            // 3. distanceTolerance를 초과하지 않는 최소 거리의 reference인덱스를 구한다.
            // Row (j) : measure point
            for (int j = 0; j < measurePoints.Count; j++) {
                int nearestIndex = -1;
                double nearestDist = Double.MaxValue;
                // Col (i) : reference point
                for (int i = 0; i < referencePoints.Count; i++) {
                    double curDistance = distanceMap[j, i];
                    if (curDistance <= distanceTolerance && // distanceTolerance 체크
                        curDistance < nearestDist) { // 최소 거리 체크
                        nearestDist = curDistance;
                        nearestIndex = i;
                    }
                }

                results.Add(nearestIndex);
            }

            return results;
        }
    }
}