package com.ruoyi.energymeter.controller;

import com.ruoyi.framework.web.domain.AjaxResult;
import com.ruoyi.energymeter.service.EnergyMonitorService;
import com.ruoyi.energymeter.vo.EnergyCollectionVO;
import com.ruoyi.energymeter.vo.EnergyRealtimeVO;
import com.ruoyi.energymeter.vo.EnergyReportVO;
import io.swagger.v3.oas.annotations.Operation;
import io.swagger.v3.oas.annotations.tags.Tag;
import jakarta.servlet.http.HttpServletResponse;
import lombok.RequiredArgsConstructor;
import org.apache.poi.ss.usermodel.BorderStyle;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.FillPatternType;
import org.apache.poi.ss.usermodel.Font;
import org.apache.poi.ss.usermodel.HorizontalAlignment;
import org.apache.poi.ss.usermodel.IndexedColors;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.VerticalAlignment;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.io.IOException;
import java.math.BigDecimal;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.List;

/**
 * 能耗数据采集、实时监控与统计报表接口。
 *
 * <p>菜单固定在前端路由，不写数据库菜单、不配角色权限；所有登录用户可见。</p>
 */
@RestController
@Tag(name = "能耗监控与统计")
@RequestMapping("/energyMeter")
@RequiredArgsConstructor
public class EnergyMonitorController {

    private final EnergyMonitorService monitorService;

    @GetMapping("/collection/overview")
    @Operation(summary = "能耗数据采集概览：三类介质接入设备、归集进度与最近批次")
    public AjaxResult collectionOverview() {
        EnergyCollectionVO vo = monitorService.collection();
        return AjaxResult.success(vo);
    }

    @GetMapping("/realtime/overview")
    @Operation(summary = "能耗实时监控：三类介质最新用量、趋势与电表实时曲线")
    public AjaxResult realtimeOverview(
            @RequestParam(required = false) Long meterId) {
        EnergyRealtimeVO vo = monitorService.realtime(meterId);
        return AjaxResult.success(vo);
    }

    @GetMapping("/report/summary")
    @Operation(summary = "能耗统计分析：按日/月、按介质/设备汇总")
    public AjaxResult reportSummary(
            @RequestParam(required = false) String startDate,
            @RequestParam(required = false) String endDate,
            @RequestParam(defaultValue = "DAY") String granularity,
            @RequestParam(defaultValue = "ALL") String meterType,
            @RequestParam(defaultValue = "MEDIUM") String dimension) {
        EnergyReportVO vo = monitorService.report(startDate, endDate, granularity, meterType, dimension);
        return AjaxResult.success(vo);
    }

    @RequestMapping(value = "/report/export", method = {RequestMethod.GET, RequestMethod.POST})
    @Operation(summary = "能耗统计报表导出 Excel")
    public void reportExport(@RequestParam(required = false) String startDate,
                             @RequestParam(required = false) String endDate,
                             @RequestParam(defaultValue = "DAY") String granularity,
                             @RequestParam(defaultValue = "ALL") String meterType,
                             HttpServletResponse response) throws IOException {
        EnergyReportVO report = monitorService.report(startDate, endDate, granularity, meterType, "MEDIUM");
        String fileName = URLEncoder.encode("能耗统计报表_" + report.getStart() + "_" + report.getEnd() + ".xlsx",
                StandardCharsets.UTF_8).replace("+", "%20");
        response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
        response.setCharacterEncoding("utf-8");
        response.setHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");
        response.setHeader("Access-Control-Expose-Headers", "Content-Disposition");
        try (Workbook workbook = new XSSFWorkbook()) {
            writeMediumSheet(workbook, report);
            writeDeviceSheet(workbook, report);
            workbook.write(response.getOutputStream());
        }
    }

    /* ------------------------------------------------------------------ */
    /* Excel                                                               */
    /* ------------------------------------------------------------------ */

    private void writeMediumSheet(Workbook workbook, EnergyReportVO report) {
        Sheet sheet = workbook.createSheet("介质汇总");
        CellStyle headStyle = headStyle(workbook);
        CellStyle numberStyle = numberStyle(workbook);
        CellStyle textStyle = textStyle(workbook);

        String[] headers = {"统计周期", "水表用量(m³)", "电表用量(度)", "蒸汽表用量(m³)"};
        Row head = sheet.createRow(0);
        for (int i = 0; i < headers.length; i++) {
            Cell cell = head.createCell(i);
            cell.setCellValue(headers[i]);
            cell.setCellStyle(headStyle);
        }

        int rowIndex = 1;
        for (EnergyReportVO.PeriodRow row : report.getRows()) {
            Row dataRow = sheet.createRow(rowIndex++);
            dataRow.createCell(0).setCellValue(row.getPeriod());
            dataRow.getCell(0).setCellStyle(textStyle);
            writeNumber(dataRow, 1, row.getWater(), numberStyle);
            writeNumber(dataRow, 2, row.getElectric(), numberStyle);
            writeNumber(dataRow, 3, row.getGas(), numberStyle);
        }
        Row totalRow = sheet.createRow(rowIndex);
        Cell totalLabel = totalRow.createCell(0);
        totalLabel.setCellValue("合计");
        totalLabel.setCellStyle(headStyle);
        for (EnergyReportVO.MediumTotal total : report.getTotals()) {
            int column = columnOf(total.getMeterType());
            if (column > 0) {
                writeNumber(totalRow, column, total.getTotal(), numberStyle);
            }
        }
        sheet.setColumnWidth(0, 18 * 256);
        for (int i = 1; i <= 3; i++) {
            sheet.setColumnWidth(i, 20 * 256);
        }
        sheet.createFreezePane(0, 1);
        sheet.setAutoFilter(new org.apache.poi.ss.util.CellRangeAddress(0, Math.max(0, rowIndex - 1), 0, 3));
    }

    private void writeDeviceSheet(Workbook workbook, EnergyReportVO report) {
        Sheet sheet = workbook.createSheet("设备明细");
        CellStyle headStyle = headStyle(workbook);
        CellStyle numberStyle = numberStyle(workbook);
        CellStyle textStyle = textStyle(workbook);

        String[] headers = {"设备名称", "表号", "介质", "采集方式", "期间用量", "单位", "占介质比例(%)"};
        Row head = sheet.createRow(0);
        for (int i = 0; i < headers.length; i++) {
            Cell cell = head.createCell(i);
            cell.setCellValue(headers[i]);
            cell.setCellStyle(headStyle);
        }

        int rowIndex = 1;
        for (EnergyReportVO.DeviceRow row : report.getDevices()) {
            Row dataRow = sheet.createRow(rowIndex++);
            createText(dataRow, 0, row.getMeterName(), textStyle);
            createText(dataRow, 1, row.getMeterAddress(), textStyle);
            createText(dataRow, 2, row.getMeterTypeName(), textStyle);
            createText(dataRow, 3, row.getSourceTypeName(), textStyle);
            writeNumber(dataRow, 4, row.getTotal(), numberStyle);
            createText(dataRow, 5, excelUnit(row.getUnit()), textStyle);
            writeNumber(dataRow, 6, row.getShare(), numberStyle);
        }
        sheet.setColumnWidth(0, 24 * 256);
        sheet.setColumnWidth(1, 22 * 256);
        for (int i = 2; i <= 6; i++) {
            sheet.setColumnWidth(i, 14 * 256);
        }
        sheet.createFreezePane(0, 1);
        sheet.setAutoFilter(new org.apache.poi.ss.util.CellRangeAddress(0, Math.max(0, rowIndex - 1), 0, 6));
    }

    private int columnOf(String meterType) {
        if ("WATER".equals(meterType)) {
            return 1;
        }
        if ("ELECTRIC".equals(meterType)) {
            return 2;
        }
        if ("GAS".equals(meterType)) {
            return 3;
        }
        return 0;
    }

    /** 界面与报表统一用「度」，底层仍按 kWh 存储。 */
    private String excelUnit(String unit) {
        if ("kWh".equals(unit)) {
            return "度";
        }
        if ("m3".equals(unit)) {
            return "m³";
        }
        return unit;
    }

    private void createText(Row row, int column, String value, CellStyle style) {
        Cell cell = row.createCell(column);
        cell.setCellValue(value == null ? "" : value);
        cell.setCellStyle(style);
    }

    private void writeNumber(Row row, int column, BigDecimal value, CellStyle style) {
        Cell cell = row.createCell(column);
        if (value != null) {
            cell.setCellValue(value.doubleValue());
        }
        cell.setCellStyle(style);
    }

    private CellStyle headStyle(Workbook workbook) {
        CellStyle style = baseStyle(workbook);
        style.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex());
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        style.setAlignment(HorizontalAlignment.CENTER);
        Font font = workbook.createFont();
        font.setBold(true);
        style.setFont(font);
        return style;
    }

    private CellStyle textStyle(Workbook workbook) {
        CellStyle style = baseStyle(workbook);
        style.setAlignment(HorizontalAlignment.LEFT);
        return style;
    }

    private CellStyle numberStyle(Workbook workbook) {
        CellStyle style = baseStyle(workbook);
        style.setAlignment(HorizontalAlignment.RIGHT);
        style.setDataFormat(workbook.createDataFormat().getFormat("#,##0.000"));
        return style;
    }

    private CellStyle baseStyle(Workbook workbook) {
        CellStyle style = workbook.createCellStyle();
        style.setBorderTop(BorderStyle.THIN);
        style.setBorderBottom(BorderStyle.THIN);
        style.setBorderLeft(BorderStyle.THIN);
        style.setBorderRight(BorderStyle.THIN);
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        return style;
    }
}