package com.terra.system.controller.data;

import com.terra.system.annotation.SysLog;
import com.terra.system.config.PropertiesConfig;
import com.terra.system.helper.StringHelper;
import com.terra.system.helper.WebHelper;
import io.swagger.v3.oas.annotations.Operation;
import io.swagger.v3.oas.annotations.Parameter;
import io.swagger.v3.oas.annotations.Parameters;
import io.swagger.v3.oas.annotations.enums.ParameterIn;
import io.swagger.v3.oas.annotations.tags.Tag;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import javax.annotation.Resource;
import org.springframework.core.io.ClassPathResource;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.ServerHttpRequest;
import org.springframework.http.server.ServerHttpResponse;
import org.springframework.http.server.ServletServerHttpRequest;
import org.springframework.http.server.ServletServerHttpResponse;

import org.springframework.web.bind.annotation.*;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.charset.StandardCharsets;
import java.time.Duration;
import java.util.Date;
import java.util.List;

/**
 * WMTS服务
 * @author WWW
 */
@Tag(name = "数据管理\\WMTS服务")
@RestController
@RequestMapping("/wmts")
public class WmtsController {
    @Resource
    PropertiesConfig config;

    private final static Log log = LogFactory.getLog(WmtsController.class);

    @SysLog()
    @Operation(summary = "获取WMTS元数据")
    @Parameters({
            @Parameter(name = "token", description = "令牌", required = true, example = "token", in = ParameterIn.PATH)
    })
    @GetMapping("select/{token}/WMTSCapabilities.xml")
    public void selectWmtsCapabilities(@PathVariable(name = "token") String token, HttpServletRequest req, HttpServletResponse res) {
        try {
            ClassPathResource resource = new ClassPathResource("wmts/web.xml");
            if (!resource.exists()) {
                return;
            }

            InputStream stream = resource.getInputStream();
            byte[] data = new byte[stream.available()];
            stream.read(data);
            stream.close();

            String url = req.getRequestURL().toString().replace("WMTSCapabilities.xml", "tile?");

            String result = new String(data, StandardCharsets.UTF_8);
            result = result.replace("{url}", url);
            byte[] bytes = result.getBytes(StandardCharsets.UTF_8);

            res.setHeader("Content-Type", "application/xml;charset=UTF-8");
            ServletOutputStream os = res.getOutputStream();
            os.write(bytes);
            os.flush();
        } catch (Exception ex) {
            log.error(ex.getMessage(), ex);
        }
    }

    @Operation(summary = "获取WMTS瓦片")
    @Parameters({
            @Parameter(name = "token", description = "令牌", required = true, example = "token", in = ParameterIn.PATH),
            @Parameter(name = "layer", description = "图层类型", required = true, example = "img"),
            @Parameter(name = "tilematrix", description = "层级", required = true),
            @Parameter(name = "tilerow", description = "行号", required = true),
            @Parameter(name = "tilecol", description = "列号", required = true)
    })
    @GetMapping("select/{token}/tile")
    public void selectWmtsTile(@PathVariable(name = "token") String token, HttpServletRequest req, HttpServletResponse res) {
        try {
            String layer = WebHelper.getReqParamVal(req, "layer");
            String matrix = WebHelper.getReqParamVal(req, "tilematrix");
            String row = WebHelper.getReqParamVal(req, "tilerow");
            String col = WebHelper.getReqParamVal(req, "tilecol");
            if (StringHelper.isEmpty(layer) || StringHelper.isEmpty(matrix) || StringHelper.isEmpty(layer) || StringHelper.isEmpty(row) || StringHelper.isEmpty(col)) {
                return;
            }

            int z = Integer.parseInt(matrix);
            int x = Integer.parseInt(row);
            int y = Integer.parseInt(col);

            getWmtsTile(layer, z, x, y, req, res);
        } catch (Exception ex) {
            log.error(ex.getMessage(), ex);
        }
    }

    /**
     * 获取WMTS瓦片
     */
    private void getWmtsTile(String layer, int z, int x, int y, HttpServletRequest req, HttpServletResponse res) throws Exception {
        ServletServerHttpRequest ssReq = new ServletServerHttpRequest(req);
        ServletServerHttpResponse ssRes = new ServletServerHttpResponse(res);

        // 检查缓存是否过期
        if (checkIfNotModify(ssReq, ssRes)) {
            // 设置缓存头
            setBrowerCache(ssRes);
            return;
        }

        // 设置缓存参数
        setBrowerCache(ssRes);
        //res.setContentType("image/png")

        // 通过response对象，获取到输出流
        ServletOutputStream outputStream = res.getOutputStream();
        // 定义输入流，通过输入流读取文件内容
        FileInputStream fileInputStream;

        // y = (int) Math.pow(2, z) - y - 1;
        String path = config.getTilePath() + File.separator + layer + File.separator + z + File.separator + y + File.separator + x + ".png";
        System.out.println(path);

        File file = new File(path);
        if (!file.exists() || file.isDirectory()) {
            ClassPathResource resource = new ClassPathResource("wmts/nofound.png");
            fileInputStream = new FileInputStream(resource.getFile());
        } else {
            System.out.println(path);
            fileInputStream = new FileInputStream(file);
        }

        int len = 0;
        byte[] bytes = new byte[1024];
        while ((len = fileInputStream.read(bytes)) != -1) {
            outputStream.write(bytes, 0, len);
            outputStream.flush();
        }
        //outputStream.close()
        fileInputStream.close();

        // 设置返回图片类型
        ssRes.getHeaders().set("Content-Type", "image/png");

        OutputStream os = ssRes.getBody();
        os.write(bytes);
        os.flush();
    }

    /**
     * 设置浏览器缓存参数
     */
    private void setBrowerCache(ServerHttpResponse res) {
        HttpHeaders headers = res.getHeaders();
        headers.setCacheControl("public, must-revalidate");

        headers.setExpires(System.currentTimeMillis() + 24 * 60 * 60 * 1000);
        headers.setAccessControlMaxAge(Duration.ofHours(24));
        headers.setETag("\"" + new Date().toString() + "\"");
        // must-revalidate
        // response.Cache.SetRevalidation(HttpCacheRevalidation.AllCaches);
    }

    /**
     * 验证缓存参数
     */
    boolean checkIfNotModify(ServerHttpRequest req, ServerHttpResponse res) {
        List<String> etags = req.getHeaders().getIfNoneMatch();
        if (0 == etags.size() || StringHelper.isEmpty(etags.get(0))) {
            return false;
        }

        res.setStatusCode(HttpStatus.NOT_MODIFIED);

        return true;
    }
}