package jnpf.dmsBusinessOccupancy;

import org.mybatis.spring.SqlSessionTemplate;
import java.util.*;
import static jnpf.dmsBusinessOccupancy.BusinessOccupancyException.Reason.*;

/** Trusted native submission adapter only. No endpoint and no client-supplied chain exemption. */
public final class BusinessFileSubmissionService {
    /** Null version is allowed only where the native form has no version field (extension). */
    public record Target(String fileId, String businessVersionId) {
        public Target {
            if (fileId == null || fileId.isBlank()) throw new IllegalArgumentException("Missing resource ID");
        }
    }
    private final BusinessOccupancyTransactions transactions;
    private final BusinessFileOccupancyCoordinator coordinator;
    private final BusinessFileEligibilityService eligibility;
    public BusinessFileSubmissionService(SqlSessionTemplate sessions) {
        transactions=new BusinessOccupancyTransactions(sessions);
        coordinator=new BusinessFileOccupancyCoordinator(sessions);
        eligibility=new BusinessFileEligibilityService(sessions);
    }

    public boolean hasOccupancy(String tenant,String task) {
        return !transactions.reader().chainOccupancies(tenant,task).isEmpty();
    }

    /** Includes first drafts: serialize native number use with the existing name-change callback. */
    public String guardCreationNumber(String tenant,String numberId,String fileName) {
        return transactions.execute(mapper->{
            String number=mapper.lockIssuedNumber(tenant,numberId);
            if(number==null || number.isBlank()) throw new IllegalArgumentException("新增审核必须选择已发放编号");
            if(!mapper.creationNumberReady(tenant,numberId,fileName))
                throw new IllegalArgumentException("编号名称正在变更或已发生变化，请重新选择编号");
            return number;
        });
    }

    /** IDs must come from the native server task/application resolution, never form parameters. */
    public void submit(String tenantId, String chainId, String applicationId, String taskId,
                       BusinessFileEligibilityService.Operation operation, List<Target> targets, boolean draft) {
        Objects.requireNonNull(operation);
        transactions.execute(mapper -> {
            var owned=mapper.chainOccupancies(tenantId,chainId);
            if (draft && owned.isEmpty()) return null;
            List<Target> submitted=List.copyOf(targets);
            if (submitted.isEmpty()) throw new IllegalArgumentException("生命周期申请至少需要一个文件");
            Map<String,Target> requested=new HashMap<>();
            for (var item:submitted) {
                if (operation != BusinessFileEligibilityService.Operation.EXTENSION
                        && (item.businessVersionId() == null || item.businessVersionId().isBlank()))
                    throw new IllegalArgumentException("当前操作必须绑定申请中的文件版本");
                if(requested.putIfAbsent(item.fileId(),item)!=null)
                    throw new IllegalArgumentException("生命周期申请不能重复选择同一文件");
            }
            var before=mapper.fileTargets(tenantId,new ArrayList<>(requested.keySet()));
            if (before.size()!=submitted.size()) throw new BusinessOccupancyException(TARGET_CHANGED);
            var numbers=new HashSet<String>();
            for (var item:before) if(!numbers.add(item.getFileNumber()))
                throw new BusinessOccupancyException(TARGET_CHANGED);
            for (var old:owned) numbers.add(old.getFileNumber());
            if (!coordinator.tryLockNumbers(tenantId,numbers)) throw new BusinessOccupancyException(NUMBER_BUSY);
            var current=mapper.fileTargets(tenantId,new ArrayList<>(requested.keySet()));
            if (!before.equals(current)) throw new BusinessOccupancyException(TARGET_CHANGED);
            owned=mapper.chainOccupancies(tenantId,chainId);
            if (!owned.isEmpty()) {
                if (owned.size()!=current.size()) throw new BusinessOccupancyException(TARGET_CHANGED);
                for (var target:current) {
                    var old=owned.stream().filter(o->Objects.equals(o.getFileNumber(),target.getFileNumber()))
                            .findFirst().orElseThrow(()->new BusinessOccupancyException(TARGET_CHANGED));
                    if (old.getReleasedAt()!=null) throw new BusinessOccupancyException(CHAIN_ALREADY_RELEASED);
                    if (!Objects.equals(old.getOperation(),operation.name())
                            || !Objects.equals(old.getApplicationId(),applicationId)
                            || !Objects.equals(old.getWorkflowTaskId(),taskId)
                            || !Objects.equals(old.getFileId(),target.getFileId())
                            || !Objects.equals(old.getBusinessVersionId(),target.getBusinessVersionId())
                            || !Objects.equals(old.getCenterVersionId(),target.getCenterVersionId()))
                        throw new BusinessOccupancyException(TARGET_CHANGED);
                    requireSubmittedVersion(requested.get(target.getFileId()),old.getBusinessVersionId());
                }
                // Same trusted chain may continue while its own candidate is pending; never reacquire.
                return null;
            }
            if (draft) return null;
            var queries=current.stream().map(t->{
                requireSubmittedVersion(requested.get(t.getFileId()),t.getBusinessVersionId());
                return new BusinessFileEligibilityService.Query(tenantId,t.getFileNumber(),t.getFileId(),
                        t.getBusinessVersionId(),operation);
            }).toList();
            var decisions=eligibility.recheckForSubmission(queries);
            for (int i=0;i<decisions.size();i++) if(!decisions.get(i).allowed())
                throw new BusinessFileIneligibleException(queries.get(i).fileNumber(),decisions.get(i).reasons());
            for (int i=0;i<current.size();i++) {
                var target=current.get(i); var row=new BusinessFileOccupancy();
                row.setTenantId(tenantId);row.setFileNumber(target.getFileNumber());row.setOperation(operation.name());
                row.setChainId(chainId);row.setApplicationId(applicationId);row.setWorkflowTaskId(taskId);
                row.setFileId(target.getFileId());row.setBusinessVersionId(target.getBusinessVersionId());
                row.setCenterVersionId(decisions.get(i).centerVersionId());row.setStage("SUBMITTED");
                coordinator.acquire(row);
            }
            return null;
        });
    }
    /** First numbered native audit; resource IDs do not exist until the final projection. */
    public void submitCreation(String tenant, String application, String task, Collection<String> numbers, boolean draft) {
        transactions.execute(mapper -> {
            var owned=mapper.chainOccupancies(tenant,task);
            if(draft && owned.isEmpty()) return null;
            var requested=new HashSet<>(numbers);
            if(requested.isEmpty() || requested.size()!=numbers.size())
                throw new IllegalArgumentException("新增审核必须包含唯一且非空的文件编号");
            var locks=new HashSet<>(requested);
            owned.forEach(row->locks.add(row.getFileNumber()));
            if(!coordinator.tryLockNumbers(tenant,locks)) throw new BusinessOccupancyException(NUMBER_BUSY);
            owned=mapper.chainOccupancies(tenant,task);
            if(!owned.isEmpty()) {
                if(owned.size()!=requested.size()) throw new BusinessOccupancyException(TARGET_CHANGED);
                for(var row:owned) {
                    if(row.getReleasedAt()!=null) throw new BusinessOccupancyException(CHAIN_ALREADY_RELEASED);
                    if(!requested.contains(row.getFileNumber()) || !"CREATE".equals(row.getOperation())
                            || !Objects.equals(application,row.getApplicationId()) || !Objects.equals(task,row.getWorkflowTaskId()))
                        throw new BusinessOccupancyException(TARGET_CHANGED);
                }
                return null; // own registered pending versions are allowed; the number set is frozen
            }
            for(String number:requested) {
                if(mapper.creationNumberUsed(tenant,number)) throw new BusinessOccupancyException(TARGET_CHANGED);
                var row=new BusinessFileOccupancy();
                row.setTenantId(tenant);row.setFileNumber(number);row.setOperation("CREATE");
                row.setChainId(task);row.setApplicationId(application);row.setWorkflowTaskId(task);row.setStage("SUBMITTED");
                coordinator.acquire(row);
            }
            return null;
        });
    }
    private static void requireSubmittedVersion(Target submitted,String expected) {
        if (submitted.businessVersionId()!=null && !Objects.equals(submitted.businessVersionId(),expected))
            throw new BusinessOccupancyException(TARGET_CHANGED);
    }
}