package com.baiyue.lastleg.appointmentplanning;

import org.springframework.stereotype.Service;
import org.springframework.http.HttpStatus;
import org.springframework.web.server.ResponseStatusException;
import java.util.List;
import java.util.Objects;
import java.util.function.Function;
import java.util.stream.Collectors;

@Service
public class AppointmentBatchPreviewService {
    private final AppointmentSourceService sources;
    private final AppointmentBatchPreviewMapper mapper;
    public AppointmentBatchPreviewService(AppointmentSourceService sources,AppointmentBatchPreviewMapper mapper) {
        this.sources=sources;this.mapper=mapper;
    }
    public record Preview(AppointmentPlanningPolicy.Group group,String originWarehouseName,
                          String destinationWarehouseCode,String destinationTimezone,List<AppointmentSourceService.Source> sources,
                          List<String> missingFields) { }
    public Preview preview(List<AppointmentCoverageService.SourceRef> refs) {
        var resolved=sources.resolveBatch(refs);
        var ids=resolved.stream().map(AppointmentSourceService.Source::orderId).filter(Objects::nonNull).distinct().toList();
        var flags=ids.isEmpty()?java.util.Map.<Long,AppointmentBatchPreviewMapper.Flags>of():mapper.flags(ids).stream()
            .collect(Collectors.toMap(AppointmentBatchPreviewMapper.Flags::orderId,Function.identity()));
        var cargo=resolved.stream().map(source->{
            String reason=source.canFollowup()?null:String.join("；",source.blockReasons());
            var state=source.orderId()==null?null:flags.get(source.orderId());
            if(source.orderId()!=null && state==null) reason="货源已变化，请重新查询";
            else if(state!=null) {
                if(state.detained()) reason="货物暂扣，请先处理后再合批";
                else if(state.mixedDestinations()) reason="货物含多个目的地，请先核对明细";
                else if(state.activeAppointment()) reason="货物已有有效预约，请编辑原预约";
            }
            // Arrival/warehouse ETA is not a cargo-ready window. Until an authoritative producer exists it stays unknown.
            return new AppointmentPlanningPolicy.Cargo(source.sourceKey(),source.customerId(),source.originWarehouseId(),
                source.destinationKey(),"US","US",source.packages(),null,null,reason==null,reason);
        }).toList();
        try {
            var group=AppointmentPlanningPolicy.group(cargo);
            return new Preview(group,resolved.get(0).originWarehouseName(),resolved.get(0).destinationWarehouseCode(),
                sources.destinationTimezone(resolved.get(0).destinationWarehouseCode()),resolved,
                group.unknownQuantitySources()>0?List.of("READY_WINDOW_UNVERIFIED","CARGO_QUANTITY_REVIEW"):List.of("READY_WINDOW_UNVERIFIED"));
        } catch(IllegalArgumentException error) {
            throw new ResponseStatusException(HttpStatus.BAD_REQUEST,error.getMessage(),error);
        }
    }
}