package com.trafficaudit.holiday.service;

import com.trafficaudit.holiday.HolidayConstants;
import com.trafficaudit.holiday.HolidayNumberUtils;
import com.trafficaudit.holiday.entity.HolidayCalendar;
import com.trafficaudit.holiday.service.HolidayStatService.DailyMetrics;
import com.trafficaudit.observation.dto.ObservationDailyOperation;
import com.trafficaudit.observation.mapper.ObservationStationFlowMapper;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.math.BigDecimal;
import java.time.LocalDate;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.function.Function;

@Service
public class HolidayTrendService {

    private static final BigDecimal HUNDRED = new BigDecimal("100");

    @Value("${holiday.trend-template:docs/专项统计/重要节假日/2026年十一假期全省综合运输客流量走势图.docx}")
    private String trendTemplatePath;

    @Resource
    private HolidayStatService statService;
    @Resource
    private HolidayConfigService configService;
    @Resource
    private HolidayTrendChartService chartService;
    @Resource
    private HolidayTrendWordService wordService;
    @Resource
    private ObservationStationFlowMapper observationStationFlowMapper;

    public byte[] generate(int year, String holidayType) {
        String holidayLabel = HolidayConstants.HOLIDAY_TYPE_LABELS.get(holidayType);
        if (holidayLabel == null) {
            throw new IllegalArgumentException("不支持的节假日类型");
        }
        List<Integer> years = Arrays.asList(year, year - 1, year - 2);
        Map<Integer, YearData> yearData = new LinkedHashMap<>();
        for (Integer item : years) {
            yearData.put(item, buildYearData(item, holidayType));
        }
        YearData selected = yearData.get(year);
        if (selected == null || !selected.hasAnyData()) {
            throw new IllegalArgumentException("所选年份没有足够的走势图数据");
        }

        String prefix = "“" + holidayLabel + "”假期";
        List<HolidayTrendWordService.DocumentBlock> blocks = new ArrayList<>();
        blocks.add(new HolidayTrendWordService.SectionBlock("一、总体情况"));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                prefix + "全省跨区域人员流动量情况",
                chartService.lineChart("万人次",
                        series(years, yearData, item -> item.totalDaily), false, 1100, 715),
                new HolidayTrendWordService.ImageSize(5268595L, 3424555L)));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                "“" + holidayLabel + "”假期累计跨区域人员流动量走势",
                chartService.lineChart("万人次",
                        series(years, yearData, item -> item.totalCumulative), false, 1100, 590),
                new HolidayTrendWordService.ImageSize(5268595L, 2821305L)));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                "“" + holidayLabel + "”假期各交通运输方式客运量占比情况",
                chartService.pieChart("人次", selected.modalShare(), 1000, 607), true,
                new HolidayTrendWordService.ImageSize(5106670L, 3097530L)));

        blocks.add(new HolidayTrendWordService.SectionBlock("二、各种运输方式客流量走势"));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                "“" + holidayLabel + "”假期自驾出行量情况",
                chartService.lineChart("万人次",
                        series(years, yearData, item -> item.selfDrivingPersonFlow), false, 1100, 522),
                new HolidayTrendWordService.ImageSize(5232400L, 2484120L)));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                "“" + holidayLabel + "”假期铁路客运量情况",
                chartService.lineChart("万人次",
                        series(years, yearData, item -> item.rail), false, 1100, 445),
                new HolidayTrendWordService.ImageSize(5264785L, 2129155L)));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                "“" + holidayLabel + "”假期水路客运量情况",
                chartService.lineChart("万人次",
                        series(years, yearData, item -> item.water), false, 1100, 433),
                new HolidayTrendWordService.ImageSize(5274310L, 2075815L)));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                "“" + holidayLabel + "”假期民航客运量情况",
                chartService.lineChart("万人次",
                        series(years, yearData, item -> item.civilAviation), false, 1100, 521),
                new HolidayTrendWordService.ImageSize(5271135L, 2496185L)));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                "“" + holidayLabel + "”假期道路客运量情况",
                chartService.lineChart("万人次",
                        series(years, yearData, item -> item.road), false, 1100, 590),
                new HolidayTrendWordService.ImageSize(5268595L, 2821305L)));

        blocks.add(new HolidayTrendWordService.SectionBlock("三、车流量走势"));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                "“" + holidayLabel + "”假期高速公路车流量情况",
                chartService.lineChart("万辆次",
                        series(years, yearData, item -> item.expressway), false, 1100, 590),
                new HolidayTrendWordService.ImageSize(5268595L, 2821305L)));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                "“" + holidayLabel + "”假期普通国省道车流量情况",
                chartService.lineChart("万辆次",
                        series(years, yearData, item -> item.nationalProvincial), false, 1100, 590),
                new HolidayTrendWordService.ImageSize(5268595L, 2821305L)));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                "“" + holidayLabel + "”假期全省车流总量情况",
                chartService.lineChart("万辆次",
                        series(years, yearData, item -> item.totalVehicleFlow), false, 1100, 590),
                new HolidayTrendWordService.ImageSize(5268595L, 2821305L)));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                "“" + holidayLabel + "”假期公路出行结构",
                chartService.stackedBarChart("万人次",
                        Arrays.asList((year - 2) + "年", (year - 1) + "年", year + "年"),
                        roadStructureSeries(years, yearData), false, 1000, 607), true,
                new HolidayTrendWordService.ImageSize(5106670L, 3097530L)));

        blocks.add(new HolidayTrendWordService.SectionBlock("附录一 每日客流构成变化"));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                "“" + holidayLabel + "”假期每日客流构成变化",
                chartService.stackedBarChart("占比",
                        HolidayTrendChartService.DAY_LABELS,
                        dailyShareSeries(selected), true, 1000, 607), true,
                new HolidayTrendWordService.ImageSize(5106670L, 3097530L)));

        blocks.add(new HolidayTrendWordService.SectionBlock("附录二 普通国省道观测站路网运行"));
        ObservationData observation = observationData(year, holidayType);
        blocks.add(new HolidayTrendWordService.ChartBlock(
                prefix + "普通国省道观测站平均机动车速度",
                chartService.lineChart("公里/小时",
                        Collections.singletonList(series("平均速度", observation.speed)), false, 1100, 590),
                new HolidayTrendWordService.ImageSize(5268595L, 2821305L)));
        blocks.add(new HolidayTrendWordService.ChartBlock(
                prefix + "普通国省道观测站平均拥挤度",
                chartService.lineChart("拥挤度",
                        Collections.singletonList(series("平均拥挤度", observation.congestion)), false, 3, 1100, 590),
                new HolidayTrendWordService.ImageSize(5268595L, 2821305L)));

        File template = resolveTemplateFile();
        if (!template.exists() || !template.isFile()) {
            throw new IllegalArgumentException("走势图模板文件不存在: " + template.getAbsolutePath());
        }
        try (InputStream input = new FileInputStream(template)) {
            return wordService.generate(readAll(input), year, blocks);
        } catch (Exception e) {
            throw new IllegalArgumentException("走势图生成失败: " + e.getMessage(), e);
        }
    }

    private YearData buildYearData(int year, String holidayType) {
        List<DailyMetrics> metrics = new ArrayList<>();
        for (int day = 1; day <= HolidayTrendChartService.DAY_LABELS.size(); day++) {
            metrics.add(statService.dailyMetrics(year, holidayType, day));
        }
        YearData data = new YearData();
        data.year = year;
        data.rail = values(metrics, DailyMetrics::getRail);
        data.civilAviation = values(metrics, DailyMetrics::getCivilAviation);
        data.road = values(metrics, DailyMetrics::getRoad);
        data.water = values(metrics, DailyMetrics::getWater);
        data.expressway = values(metrics, DailyMetrics::getExpressway);
        data.nationalProvincial = values(metrics, DailyMetrics::getNationalProvincial);
        data.selfDrivingPersonFlow = values(metrics, DailyMetrics::getNonBusinessPersonFlow);
        data.selfDrivingVehicleFlow = combine(metrics,
                DailyMetrics::getExpressway, DailyMetrics::getNationalProvincial);
        data.totalVehicleFlow = combine(metrics,
                DailyMetrics::getExpressway, DailyMetrics::getNationalProvincial);
        data.totalDaily = values(metrics, DailyMetrics::getTotalPersonFlow);
        data.totalCumulative = cumulative(data.totalDaily);
        data.railCumulative = cumulative(data.rail);
        data.civilAviationCumulative = cumulative(data.civilAviation);
        data.roadCumulative = cumulative(data.road);
        data.waterCumulative = cumulative(data.water);
        data.selfDrivingPersonFlowCumulative = cumulative(data.selfDrivingPersonFlow);
        return data;
    }

    private List<HolidayTrendChartService.ChartSeries> series(
            List<Integer> years, Map<Integer, YearData> data,
            Function<YearData, List<BigDecimal>> selector) {
        List<HolidayTrendChartService.ChartSeries> result = new ArrayList<>();
        for (Integer year : years) {
            YearData item = data.get(year);
            result.add(series(year + "年", selector.apply(item)));
        }
        return result;
    }

    private List<HolidayTrendChartService.ChartSeries> yoySeries(
            String label, List<Integer> years, Map<Integer, YearData> data,
            Function<YearData, List<BigDecimal>> selector) {
        List<HolidayTrendChartService.ChartSeries> result = new ArrayList<>();
        YearData selected = data.get(years.get(0));
        List<BigDecimal> selectedValues = selector.apply(selected);
        for (int i = 1; i < years.size(); i++) {
            YearData comparison = data.get(years.get(i));
            result.add(series(label + "同比" + comparison.year,
                    percentageChanges(selectedValues, selector.apply(comparison))));
        }
        return result;
    }

    private List<HolidayTrendChartService.ChartSeries> dailyShareSeries(YearData data) {
        List<HolidayTrendChartService.ChartSeries> result = new ArrayList<>();
        result.add(series("自驾", share(data.selfDrivingPersonFlow, data)));
        result.add(series("道路", share(data.road, data)));
        result.add(series("铁路", share(data.rail, data)));
        result.add(series("民航", share(data.civilAviation, data)));
        result.add(series("水路", share(data.water, data)));
        return result;
    }

    private List<BigDecimal> share(List<BigDecimal> values, YearData data) {
        List<BigDecimal> result = new ArrayList<>();
        for (int i = 0; i < HolidayTrendChartService.DAY_LABELS.size(); i++) {
            BigDecimal total = dayTotal(data, i);
            BigDecimal value = valueAt(values, i);
            result.add(total == null || total.signum() == 0
                    ? null : HolidayNumberUtils.divide(value == null ? BigDecimal.ZERO : value, total));
        }
        return result;
    }

    private BigDecimal dayTotal(YearData data, int index) {
        BigDecimal total = BigDecimal.ZERO;
        boolean hasValue = false;
        for (List<BigDecimal> values : Arrays.asList(
                data.selfDrivingPersonFlow, data.road, data.rail,
                data.civilAviation, data.water)) {
            BigDecimal value = valueAt(values, index);
            if (value != null) {
                total = total.add(value);
                hasValue = true;
            }
        }
        return hasValue ? HolidayNumberUtils.normalize(total) : null;
    }

    private List<HolidayTrendChartService.ChartSeries> roadStructureSeries(
            List<Integer> years, Map<Integer, YearData> data) {
        List<BigDecimal> road = new ArrayList<>();
        List<BigDecimal> selfDriving = new ArrayList<>();
        for (int i = years.size() - 1; i >= 0; i--) {
            YearData item = data.get(years.get(i));
            road.add(sum(item.road));
            selfDriving.add(sum(item.selfDrivingPersonFlow));
        }
        return Arrays.asList(
                series("自驾出行量", selfDriving),
                series("道路客运量", road));
    }

    private ObservationData observationData(int year, String holidayType) {
        List<HolidayCalendar> days = configService.findHolidayDays(year, holidayType);
        if (days.isEmpty()) {
            return new ObservationData(nulls(), nulls());
        }
        LocalDate start = days.get(0).getHolidayDate();
        LocalDate end = start.plusDays(HolidayTrendChartService.DAY_LABELS.size() - 1L);
        List<ObservationDailyOperation> rows = observationStationFlowMapper.selectDailyOperations(start, end);
        Map<LocalDate, ObservationDailyOperation> byDate = new LinkedHashMap<>();
        for (ObservationDailyOperation row : rows) {
            byDate.put(row.getObsDate(), row);
        }
        List<BigDecimal> speed = new ArrayList<>();
        List<BigDecimal> congestion = new ArrayList<>();
        for (int i = 0; i < HolidayTrendChartService.DAY_LABELS.size(); i++) {
            ObservationDailyOperation row = byDate.get(start.plusDays(i));
            speed.add(row == null ? null : row.getAverageSpeed());
            congestion.add(row == null ? null : row.getAverageCongestion());
        }
        return new ObservationData(speed, congestion);
    }

    private HolidayTrendChartService.ChartSeries series(String name, List<BigDecimal> values) {
        HolidayTrendChartService.ChartSeries result = new HolidayTrendChartService.ChartSeries();
        result.setName(name);
        result.setValues(values == null ? nulls() : values);
        return result;
    }

    private List<BigDecimal> values(List<DailyMetrics> metrics, Function<DailyMetrics, BigDecimal> selector) {
        List<BigDecimal> result = new ArrayList<>();
        for (DailyMetrics item : metrics) {
            result.add(item == null ? null : selector.apply(item));
        }
        return result;
    }

    private List<BigDecimal> combine(List<DailyMetrics> metrics,
                                     Function<DailyMetrics, BigDecimal> left,
                                     Function<DailyMetrics, BigDecimal> right) {
        List<BigDecimal> result = new ArrayList<>();
        for (DailyMetrics item : metrics) {
            result.add(item == null ? null : HolidayNumberUtils.sumNullable(left.apply(item), right.apply(item)));
        }
        return result;
    }

    private List<BigDecimal> cumulative(List<BigDecimal> values) {
        List<BigDecimal> result = new ArrayList<>();
        BigDecimal total = null;
        for (BigDecimal value : values) {
            if (value != null) total = HolidayNumberUtils.sumNullable(total, value);
            result.add(value == null ? null : total);
        }
        return result;
    }

    private List<BigDecimal> percentageChanges(List<BigDecimal> current, List<BigDecimal> previous) {
        List<BigDecimal> result = new ArrayList<>();
        for (int i = 0; i < HolidayTrendChartService.DAY_LABELS.size(); i++) {
            BigDecimal currentValue = valueAt(current, i);
            BigDecimal previousValue = valueAt(previous, i);
            BigDecimal ratio = HolidayNumberUtils.divide(currentValue, previousValue);
            result.add(ratio == null ? null : HolidayNumberUtils.multiply(
                    ratio.subtract(BigDecimal.ONE), HUNDRED));
        }
        return result;
    }

    private BigDecimal sum(List<BigDecimal> values) {
        BigDecimal total = null;
        for (BigDecimal value : values) {
            if (value != null) total = HolidayNumberUtils.sumNullable(total, value);
        }
        return total;
    }

    private BigDecimal valueAt(List<BigDecimal> values, int index) {
        return values == null || index >= values.size() ? null : values.get(index);
    }

    private List<BigDecimal> nulls() {
        List<BigDecimal> result = new ArrayList<>();
        for (int i = 0; i < HolidayTrendChartService.DAY_LABELS.size(); i++) result.add(null);
        return result;
    }

    private File resolveTemplateFile() {
        List<File> candidates = new ArrayList<>();
        File configured = new File(trendTemplatePath);
        candidates.add(configured);
        if (!configured.isAbsolute()) {
            candidates.add(new File(System.getProperty("user.dir"), trendTemplatePath));
            candidates.add(new File(System.getProperty("user.dir"), "../" + trendTemplatePath));
        }
        for (File candidate : candidates) {
            try {
                if (candidate.exists() && candidate.isFile()) return candidate.getCanonicalFile();
            } catch (Exception ignored) {
                // Keep checking.
            }
        }
        return configured;
    }

    private byte[] readAll(InputStream input) throws Exception {
        java.io.ByteArrayOutputStream output = new java.io.ByteArrayOutputStream();
        byte[] buffer = new byte[8192];
        int length;
        while ((length = input.read(buffer)) > 0) {
            output.write(buffer, 0, length);
        }
        return output.toByteArray();
    }

    private static class YearData {
        private int year;
        private List<BigDecimal> rail;
        private List<BigDecimal> civilAviation;
        private List<BigDecimal> road;
        private List<BigDecimal> water;
        private List<BigDecimal> expressway;
        private List<BigDecimal> nationalProvincial;
        private List<BigDecimal> selfDrivingPersonFlow;
        private List<BigDecimal> selfDrivingVehicleFlow;
        private List<BigDecimal> totalVehicleFlow;
        private List<BigDecimal> totalDaily;
        private List<BigDecimal> totalCumulative;
        private List<BigDecimal> railCumulative;
        private List<BigDecimal> civilAviationCumulative;
        private List<BigDecimal> roadCumulative;
        private List<BigDecimal> waterCumulative;
        private List<BigDecimal> selfDrivingPersonFlowCumulative;

        private boolean hasAnyData() {
            return hasValue(totalDaily) || hasValue(rail) || hasValue(road)
                    || hasValue(expressway) || hasValue(nationalProvincial);
        }

        private boolean hasValue(List<BigDecimal> values) {
            if (values == null) return false;
            for (BigDecimal value : values) {
                if (value != null) return true;
            }
            return false;
        }

        private List<HolidayTrendChartService.ChartCategory> modalShare() {
            List<HolidayTrendChartService.ChartCategory> result = new ArrayList<>();
            result.add(category("自驾", sum(selfDrivingPersonFlow)));
            result.add(category("道路", sum(road)));
            result.add(category("铁路", sum(rail)));
            result.add(category("民航", sum(civilAviation)));
            result.add(category("水路", sum(water)));
            return result;
        }

        private BigDecimal sum(List<BigDecimal> values) {
            BigDecimal total = null;
            for (BigDecimal value : values) {
                if (value != null) total = HolidayNumberUtils.sumNullable(total, value);
            }
            return total;
        }

        private HolidayTrendChartService.ChartCategory category(String name, BigDecimal value) {
            HolidayTrendChartService.ChartCategory category = new HolidayTrendChartService.ChartCategory();
            category.setName(name);
            category.setValue(value == null ? BigDecimal.ZERO : value);
            return category;
        }
    }

    private static class ObservationData {
        private final List<BigDecimal> speed;
        private final List<BigDecimal> congestion;

        private ObservationData(List<BigDecimal> speed, List<BigDecimal> congestion) {
            this.speed = speed;
            this.congestion = congestion;
        }
    }
}