package gecaoji; // 包声明
import java.awt.BasicStroke; // 引入基础描边类
import java.awt.Color; // 引入颜色类
import java.awt.Graphics2D; // 引入2D图形上下文
import java.awt.Stroke; // 引入描边接口
import java.awt.geom.Path2D; // 引入路径绘制类
import java.awt.geom.Point2D; // 引入二维点类
import java.util.ArrayList; // 引入动态数组
import java.util.List; // 引入列表接口
import org.locationtech.jts.geom.Coordinate; // 引入坐标类
import org.locationtech.jts.geom.GeometryFactory; // 引入几何工厂类
import org.locationtech.jts.geom.Polygon; // 引入多边形类

/** // 文档注释开头
 * Helper class to parse and render planned mowing paths. // 辅助类说明
 */ // 文档注释结尾
public final class lujingdraw { // 类定义，防止继承
    // 马尔斯绿色 (RGB: 102, 205, 170) - 用于内缩边界（围边）
    private static final Color INNER_BOUNDARY_COLOR = new Color(102, 205, 170);
    // 提香红透明度70% (RGB: 210, 4, 45, alpha: 178) - 用于割草作业路径
    private static final Color MOWING_PATH_COLOR = new Color(210, 4, 45, 178);
    // 蓝色 - 用于非作业移动路径
    private static final Color TRAVEL_PATH_COLOR = new Color(0, 0, 255);
    // 虚线样式 - 用于非作业移动路径
    private static final float[] DASH_PATTERN = {5.0f, 5.0f};
    private static final Color START_POINT_COLOR = new Color(0, 0, 0, 220); // 起点箭头颜色
    private static final Color END_POINT_COLOR = new Color(0, 0, 0, 220); // 终点箭头颜色

    private lujingdraw() { // 私有构造防止实例化
    } // 空实现

    // 解析结果：包含点与每个相邻段的作业标注（size=points.size()-1）
    public static final class ParsedPath {
        public final List<Point2D.Double> points;
        public final List<Boolean> isMowingFlags; // 每段对应标注：true=作业段，false=旅行段
        public ParsedPath(List<Point2D.Double> points, List<Boolean> flags) {
            this.points = points;
            this.isMowingFlags = flags;
        }
    }

    /** // 文档注释开始
     * Parse the planned path string (semicolon-separated "x,y" pairs) into a list of points in meters. // 方法说明
     */ // 文档注释结束
    public static List<Point2D.Double> parsePlannedPath(String plannedPath) { // 解析路径字符串
        List<Point2D.Double> points = new ArrayList<>(); // 存放解析后的点集
        if (plannedPath == null) { // 判空
            return points; // 返回空集合
        } // if结束

        String normalized = plannedPath.trim(); // 去除首尾空格
        if (normalized.isEmpty() || "-1".equals(normalized)) { // 无效判断
            return points; // 返回空集合
        } // if结束

        int commentIndex = normalized.indexOf('#'); // 查找注释符号
        if (commentIndex >= 0) { // 找到注释
            normalized = normalized.substring(0, commentIndex).trim(); // 截取注释前内容
        } // if结束

        if (normalized.isEmpty()) { // 再次判空
            return points; // 返回空集合
        } // if结束

        String[] segments = normalized.split(";"); // 切分各段
        for (String segment : segments) { // 遍历每段
            if (segment == null) { // 判空
                continue; // 跳过
            } // if结束
            String trimmed = segment.trim(); // 去除空格
            if (trimmed.isEmpty()) { // 空段
                continue; // 跳过
            } // if结束
            String[] parts = trimmed.split(","); // 切分坐标
            if (parts.length < 2) { // 检查长度
                continue; // 跳过
            } // if结束
            try { // 数值解析
                double x = Double.parseDouble(parts[0].trim()); // 解析X坐标
                double y = Double.parseDouble(parts[1].trim()); // 解析Y坐标
                points.add(new Point2D.Double(x, y)); // 加入点集
            } catch (NumberFormatException ignored) { // 捕获格式异常
                // Ignore malformed coordinates // 忽略非法坐标
            } // try结束
        } // for结束
        return points; // 返回结果
    } // 方法结束

    /**
     * 解析带段标注的路径字符串。格式：第一个点 "x,y"；后续点可为 "x,y,M" 或 "x,y,T"，分别表示上一点至当前点为作业段或旅行段。
     * 兼容旧格式（无第三字段），此时 flags 返回 null。
     */
    public static ParsedPath parsePlannedPathWithFlags(String plannedPath) {
        List<Point2D.Double> points = new ArrayList<>();
        List<Boolean> flags = new ArrayList<>();
        if (plannedPath == null) {
            return new ParsedPath(points, null);
        }
        String normalized = plannedPath.trim();
        if (normalized.isEmpty() || "-1".equals(normalized)) {
            return new ParsedPath(points, null);
        }
        int commentIndex = normalized.indexOf('#');
        if (commentIndex >= 0) {
            normalized = normalized.substring(0, commentIndex).trim();
        }
        if (normalized.isEmpty()) {
            return new ParsedPath(points, null);
        }
        String[] segments = normalized.split(";");
        boolean sawTypeField = false;
        for (int i = 0; i < segments.length; i++) {
            String segment = segments[i];
            if (segment == null) continue;
            String trimmed = segment.trim();
            if (trimmed.isEmpty()) continue;
            String[] parts = trimmed.split(",");
            if (parts.length < 2) continue;
            try {
                double x = Double.parseDouble(parts[0].trim());
                double y = Double.parseDouble(parts[1].trim());
                points.add(new Point2D.Double(x, y));
                if (i > 0) {
                    // 第一个点无标注；后续若存在第三字段则解析
                    if (parts.length >= 3) {
                        String t = parts[2].trim();
                        boolean isMowing = t.equalsIgnoreCase("M") || t.equalsIgnoreCase("m") || t.equals("1") || t.equalsIgnoreCase("WORK");
                        flags.add(isMowing);
                        sawTypeField = true;
                    } else {
                        flags.add(Boolean.TRUE); // 默认作业段，便于向后兼容
                    }
                }
            } catch (NumberFormatException ignored) {
                // 忽略非法坐标
            }
        }
        return new ParsedPath(points, sawTypeField ? flags : null);
    }

    /** // 文档注释开始
     * Draw the planned mowing path. // 绘制路径
     */ // 文档注释结束
    public static void drawPlannedPath(Graphics2D g2d, List<Point2D.Double> path, double scale, double arrowScale) { // 绘制主方法
        drawPlannedPath(g2d, path, scale, arrowScale, null, null, null, null, null); // 调用重载方法
    } // 方法结束
    
    /** // 文档注释开始
     * Draw the planned mowing path with segment information. // 绘制路径（带段信息）
     * @param boundaryCoords 地块边界坐标字符串，用于绘制内缩边界
     * @param mowingWidth 割草宽度（米），字符串格式
     * @param safetyDistance 安全距离（米），字符串格式
     * @param obstaclesCoords 障碍物坐标字符串
     * @param mowingPattern 割草模式（"parallel"或"spiral"）
     */ // 文档注释结束
    public static void drawPlannedPath(Graphics2D g2d, List<Point2D.Double> path, double scale, double arrowScale, 
                                      String boundaryCoords, String mowingWidth, String safetyDistance, String obstaclesCoords, String mowingPattern) { // 绘制主方法（重载）
        if (path == null || path.size() < 2) { // 判定点数
            return; // 数据不足直接返回
        } // if结束

        Stroke previous = g2d.getStroke(); // 保存原描边
        float strokeWidth = (float) (2.5 / Math.max(0.5, scale)); // 根据缩放计算线宽
        
        // 1. 绘制内缩边界（围边）- 马尔斯绿色
        if (boundaryCoords != null && !boundaryCoords.trim().isEmpty() && !"-1".equals(boundaryCoords.trim())) {
            drawInnerBoundary(g2d, boundaryCoords, safetyDistance, scale);
        }
        
        // 2. 按段绘制路径（逐段绘制，避免将不相邻段首尾连成越界直线）
        org.locationtech.jts.geom.Geometry innerBoundaryGeom = buildInnerBoundaryGeom(boundaryCoords, safetyDistance);
        for (int i = 1; i < path.size(); i++) {
            Point2D.Double a = path.get(i - 1);
            Point2D.Double b = path.get(i);

            Path2D segment = new Path2D.Double();
            segment.moveTo(a.x, a.y);
            segment.lineTo(b.x, b.y);

            boolean inside = true; // 默认按作业段绘制
            if (innerBoundaryGeom != null) {
                inside = isSegmentInsideInnerBoundary(innerBoundaryGeom, a, b);
            }

            if (inside) {
                // 作业段：实线 + 提香红
                g2d.setStroke(new BasicStroke(strokeWidth, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
                g2d.setColor(MOWING_PATH_COLOR);
            } else {
                // 旅行段（或沿边界段）：虚线 + 蓝色
                g2d.setStroke(new BasicStroke(strokeWidth, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND, 10.0f, DASH_PATTERN, 0.0f));
                g2d.setColor(TRAVEL_PATH_COLOR);
            }
            g2d.draw(segment);
        }
        
        Point2D.Double start = path.get(0); // 起点
        Point2D.Double second = path.size() > 1 ? path.get(1) : path.get(0); // 第二个点
        Point2D.Double end = path.get(path.size() - 1); // 终点
        Point2D.Double prev = path.size() > 1 ? path.get(path.size() - 2) : path.get(path.size() - 1); // 倒数第二个点

        drawArrowMarker(g2d, start, second, START_POINT_COLOR, scale, arrowScale); // 绘制起点箭头
        drawArrowMarker(g2d, prev, end, END_POINT_COLOR, scale, arrowScale); // 绘制终点箭头

        g2d.setStroke(previous); // 恢复原描边
    } // 方法结束

    /**
     * 使用算法端提供的段标注绘制路径（优先使用标注，不做内缩边界推断）。
     * flags.size() 必须为 path.size()-1。
     */
    public static void drawPlannedPath(Graphics2D g2d, List<Point2D.Double> path, List<Boolean> flags,
                                       double scale, double arrowScale,
                                       String boundaryCoords, String mowingWidth, String safetyDistance,
                                       String obstaclesCoords, String mowingPattern) {
        if (path == null || path.size() < 2 || flags == null || flags.size() != path.size() - 1) {
            // 回退到推断版本
            drawPlannedPath(g2d, path, scale, arrowScale, boundaryCoords, mowingWidth, safetyDistance, obstaclesCoords, mowingPattern);
            return;
        }

        Stroke previous = g2d.getStroke();
        float strokeWidth = (float) (2.5 / Math.max(0.5, scale));

        // 1. 绘制内缩边界（围边）
        if (boundaryCoords != null && !boundaryCoords.trim().isEmpty() && !"-1".equals(boundaryCoords.trim())) {
            drawInnerBoundary(g2d, boundaryCoords, safetyDistance, scale);
        }

        // 2. 按段绘制，完全遵循算法端标注
        for (int i = 1; i < path.size(); i++) {
            Point2D.Double a = path.get(i - 1);
            Point2D.Double b = path.get(i);
            boolean isMowing = Boolean.TRUE.equals(flags.get(i - 1));

            Path2D segment = new Path2D.Double();
            segment.moveTo(a.x, a.y);
            segment.lineTo(b.x, b.y);

            if (isMowing) {
                g2d.setStroke(new BasicStroke(strokeWidth, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
                g2d.setColor(MOWING_PATH_COLOR);
            } else {
                g2d.setStroke(new BasicStroke(strokeWidth, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND, 10.0f, DASH_PATTERN, 0.0f));
                g2d.setColor(TRAVEL_PATH_COLOR);
            }
            g2d.draw(segment);
        }

        Point2D.Double start = path.get(0);
        Point2D.Double second = path.size() > 1 ? path.get(1) : path.get(0);
        Point2D.Double end = path.get(path.size() - 1);
        Point2D.Double prev = path.size() > 1 ? path.get(path.size() - 2) : path.get(path.size() - 1);

        drawArrowMarker(g2d, start, second, START_POINT_COLOR, scale, arrowScale);
        drawArrowMarker(g2d, prev, end, END_POINT_COLOR, scale, arrowScale);

        g2d.setStroke(previous);
    }

    // 构建内缩边界几何体，用于安全检测与分段绘制
    private static org.locationtech.jts.geom.Geometry buildInnerBoundaryGeom(String boundaryCoords, String safetyDistanceStr) {
        try {
            if (boundaryCoords == null || boundaryCoords.trim().isEmpty() || "-1".equals(boundaryCoords.trim())) {
                return null;
            }
            List<Coordinate> boundary = parseCoordinates(boundaryCoords);
            if (boundary.size() < 4) {
                return null; // 边界点不足
            }
            double safetyDistance = 0.2; // 默认0.2米
            if (safetyDistanceStr != null && !safetyDistanceStr.trim().isEmpty()) {
                try {
                    safetyDistance = Double.parseDouble(safetyDistanceStr.trim());
                } catch (NumberFormatException ignored) {}
            }
            GeometryFactory gf = new GeometryFactory();
            Polygon poly = gf.createPolygon(gf.createLinearRing(boundary.toArray(new Coordinate[0])));
            if (!poly.isValid()) {
                poly = (Polygon) poly.buffer(0);
            }
            org.locationtech.jts.geom.Geometry innerBoundary = poly.buffer(-safetyDistance);
            if (innerBoundary == null || innerBoundary.isEmpty()) {
                return null;
            }
            return innerBoundary;
        } catch (Exception e) {
            return null;
        }
    }

    // 判断一段是否在内缩边界内或沿边界（不越界）
    private static boolean isSegmentInsideInnerBoundary(org.locationtech.jts.geom.Geometry innerBoundary, Point2D.Double a, Point2D.Double b) {
        try {
            GeometryFactory gf = new GeometryFactory();
            Coordinate[] seg = new Coordinate[] { new Coordinate(a.x, a.y), new Coordinate(b.x, b.y) };
            org.locationtech.jts.geom.LineString ls = gf.createLineString(seg);
            // 包含或覆盖均视为合法，不与内边界外部交叉
            if (innerBoundary.contains(ls) || innerBoundary.covers(ls)) {
                return true;
            }
            // 如与内边界边界相交，视为不在内部（用于改变样式并断开连线）
            return !ls.crosses(innerBoundary.getBoundary());
        } catch (Exception e) {
            return true; // 检测异常时，按作业段处理以不中断绘制
        }
    }
    
    /** // 文档注释开始
     * 绘制内缩边界（围边）- 马尔斯绿色
     */ // 文档注释结束
    private static void drawInnerBoundary(Graphics2D g2d, String boundaryCoords, String safetyDistanceStr, double scale) {
        try {
            List<Coordinate> boundary = parseCoordinates(boundaryCoords);
            if (boundary.size() < 4) {
                return; // 边界点不足
            }
            
            // 解析安全距离
            double safetyDistance = 0.2; // 默认0.2米
            if (safetyDistanceStr != null && !safetyDistanceStr.trim().isEmpty()) {
                try {
                    safetyDistance = Double.parseDouble(safetyDistanceStr.trim());
                } catch (NumberFormatException e) {
                    // 使用默认值
                }
            }
            
            // 创建多边形并内缩
            GeometryFactory gf = new GeometryFactory();
            Polygon poly = gf.createPolygon(gf.createLinearRing(boundary.toArray(new Coordinate[0])));
            if (!poly.isValid()) {
                poly = (Polygon) poly.buffer(0);
            }
            
            // 内缩生成安全边界
            org.locationtech.jts.geom.Geometry innerBoundary = poly.buffer(-safetyDistance);
            if (innerBoundary == null || innerBoundary.isEmpty()) {
                return;
            }
            
            // 绘制内缩边界
            g2d.setColor(INNER_BOUNDARY_COLOR); // 马尔斯绿色
            float strokeWidth = (float) (3.0 / Math.max(0.5, scale));
            g2d.setStroke(new BasicStroke(strokeWidth, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND));
            
            // 将JTS几何体转换为Path2D并绘制
            Path2D.Double innerPath = geometryToPath2D(innerBoundary);
            if (innerPath != null) {
                g2d.draw(innerPath);
            }
        } catch (Exception e) {
            // 绘制失败时忽略，不影响其他路径绘制
        }
    } // 方法结束
    
    /** // 文档注释开始
     * 将JTS几何体转换为Path2D
     */ // 文档注释结束
    private static Path2D.Double geometryToPath2D(org.locationtech.jts.geom.Geometry geom) {
        if (geom == null) {
            return null;
        }
        Path2D.Double path = new Path2D.Double();
        if (geom instanceof Polygon) {
            Polygon poly = (Polygon) geom;
            addRingToPath(path, poly.getExteriorRing().getCoordinates(), true);
            for (int i = 0; i < poly.getNumInteriorRing(); i++) {
                addRingToPath(path, poly.getInteriorRingN(i).getCoordinates(), true);
            }
        } else if (geom instanceof org.locationtech.jts.geom.MultiPolygon) {
            org.locationtech.jts.geom.MultiPolygon mp = (org.locationtech.jts.geom.MultiPolygon) geom;
            for (int i = 0; i < mp.getNumGeometries(); i++) {
                Polygon poly = (Polygon) mp.getGeometryN(i);
                addRingToPath(path, poly.getExteriorRing().getCoordinates(), true);
                for (int j = 0; j < poly.getNumInteriorRing(); j++) {
                    addRingToPath(path, poly.getInteriorRingN(j).getCoordinates(), true);
                }
            }
        }
        return path;
    } // 方法结束
    
    /** // 文档注释开始
     * 将坐标环添加到Path2D
     */ // 文档注释结束
    private static void addRingToPath(Path2D.Double path, Coordinate[] coords, boolean close) {
        if (coords == null || coords.length < 2) {
            return;
        }
        path.moveTo(coords[0].x, coords[0].y);
        for (int i = 1; i < coords.length; i++) {
            path.lineTo(coords[i].x, coords[i].y);
        }
        if (close) {
            path.closePath();
        }
    } // 方法结束
    

    
    /** // 文档注释开始
     * 比较两个坐标是否相同（容差）
     */ // 文档注释结束
    private static boolean equals2D(Coordinate a, Coordinate b) {
        if (a == b) return true;
        if (a == null || b == null) return false;
        return a.distance(b) < 1e-4;
    } // 方法结束

    private static void drawArrowMarker(Graphics2D g2d, Point2D.Double from, Point2D.Double to, Color color, double scale, double sizeScale) { // 绘制箭头辅助
        if (from == null || to == null) { // 判空
            return; // 数据不足返回
        } // if结束
        double dx = to.x - from.x; // 计算X增量
        double dy = to.y - from.y; // 计算Y增量
        double length = Math.hypot(dx, dy); // 计算向量长度
        if (length == 0) { // 防止零长度
            return; // 无方向返回
        } // if结束

    double arrowLength = Math.max(2.5, 5.5 / Math.max(0.5, scale)); // 计算箭头长度
    double clampedScale = sizeScale > 0 ? sizeScale : 1.0; // 防止非法缩放
    arrowLength *= 0.25 * clampedScale; // 缩小箭头至原来的一半
        double arrowWidth = arrowLength * 0.45; // 计算箭头宽度

        double ux = dx / length; // 单位向量X
        double uy = dy / length; // 单位向量Y

        double tipX = to.x; // 箭头尖端X
        double tipY = to.y; // 箭头尖端Y
        double baseX = tipX - ux * arrowLength; // 箭头底部X
        double baseY = tipY - uy * arrowLength; // 箭头底部Y

        double perpX = -uy; // 垂直向量X
        double perpY = ux; // 垂直向量Y

        double leftX = baseX + perpX * arrowWidth * 0.5; // 左侧点X
        double leftY = baseY + perpY * arrowWidth * 0.5; // 左侧点Y
        double rightX = baseX - perpX * arrowWidth * 0.5; // 右侧点X
        double rightY = baseY - perpY * arrowWidth * 0.5; // 右侧点Y

        Path2D arrow = new Path2D.Double(); // 创建箭头路径
        arrow.moveTo(tipX, tipY); // 起点移动到尖端
        arrow.lineTo(leftX, leftY); // 连到左侧
        arrow.lineTo(rightX, rightY); // 连到右侧
        arrow.closePath(); // 闭合形成三角形

        g2d.setColor(color); // 设置颜色
        g2d.fill(arrow); // 填充箭头
    } // 方法结束

    /**
     * 解析坐标字符串
     */
    private static List<Coordinate> parseCoordinates(String s) {
        List<Coordinate> list = new ArrayList<>();
        if (s == null || s.trim().isEmpty()) return list;
        // 增强正则：处理可能存在的多种分隔符
        String[] pts = s.split("[;\\s]+");
        for (String p : pts) {
            String trimmed = p.trim().replace("(", "").replace(")", "");
            if (trimmed.isEmpty()) continue;
            String[] xy = trimmed.split("[,，\\s]+");
            if (xy.length >= 2) {
                try {
                    double x = Double.parseDouble(xy[0].trim());
                    double y = Double.parseDouble(xy[1].trim());
                    // 过滤无效坐标
                    if (!Double.isNaN(x) && !Double.isNaN(y) && !Double.isInfinite(x) && !Double.isInfinite(y)) {
                        list.add(new Coordinate(x, y));
                    }
                } catch (NumberFormatException ex) {
                    // 忽略解析错误的点
                }
            }
        }
        // 确保多边形闭合
        if (list.size() > 2 && !list.get(0).equals2D(list.get(list.size() - 1))) {
            list.add(new Coordinate(list.get(0)));
        }
        return list;
    }
} // 类结束