import 'package:flutter_test/flutter_test.dart';
import 'package:uto_manager/domain/entities/authorized_rank.dart';
import 'package:uto_manager/domain/entities/doctrinal_branch.dart';
import 'package:uto_manager/domain/entities/echelon.dart';
import 'package:uto_manager/domain/entities/personnel_record.dart';
import 'package:uto_manager/domain/entities/position_slot.dart';
import 'package:uto_manager/domain/entities/unit_node.dart';
import 'package:uto_manager/domain/services/assignment_service.dart';
import 'package:uto_manager/domain/services/unit_tree_service.dart';
import 'package:uto_manager/domain/value_objects/duty_mos.dart';

void main() {
  const treeService = UnitTreeService();
  const service = AssignmentService(treeService: treeService);

  PositionSlot makeSlot({
    String slotId = 's1',
    String unitId = 'u1',
    String mosCode = '11B',
    AuthorizedRank rank = AuthorizedRank.e5,
    bool isKeyLeader = false,
    String? assignedPersonnelId,
  }) {
    return PositionSlot(
      slotId: slotId,
      unitId: unitId,
      positionTitle: 'Test Position',
      dutyMos: DutyMos(mosCode),
      authorizedRank: rank,
      isKeyLeader: isKeyLeader,
      assignedPersonnelId: assignedPersonnelId,
    );
  }

  PersonnelRecord makeSoldier({
    String id = 'p1',
    String mosCode = '11B',
    AuthorizedRank rank = AuthorizedRank.e5,
    String? assignedSlotId,
    ReadinessState readiness = ReadinessState.fullyMissionCapable,
  }) {
    return PersonnelRecord(
      soldierId: id,
      name: 'SGT Test',
      primaryMos: DutyMos(mosCode),
      payGrade: rank,
      readinessState: readiness,
      assignedSlotId: assignedSlotId,
    );
  }

  // ---------------------------------------------------------------------------
  // assign
  // ---------------------------------------------------------------------------

  group('assign', () {
    test('successful assignment returns success outcome', () {
      final slot = makeSlot();
      final soldier = makeSoldier();
      final outcome = service.assign(slot, soldier);
      expect(outcome.isSuccess, isTrue);
      expect(outcome.updatedSlot?.assignedPersonnelId, 'p1');
      expect(outcome.updatedSoldier?.assignedSlotId, 's1');
    });

    test('assignment to filled slot returns failure', () {
      final slot = makeSlot(assignedPersonnelId: 'existing');
      final soldier = makeSoldier();
      final outcome = service.assign(slot, soldier);
      expect(outcome.isSuccess, isFalse);
      expect(outcome.failureReason, contains('already filled'));
    });

    test('assignment of already-assigned soldier returns failure', () {
      final slot = makeSlot();
      final soldier = makeSoldier(assignedSlotId: 'other-slot');
      final outcome = service.assign(slot, soldier);
      expect(outcome.isSuccess, isFalse);
      expect(outcome.failureReason, contains('already assigned'));
    });

    test('MOS mismatch is flagged but does not block assignment', () {
      final slot = makeSlot(mosCode: '68W');
      final soldier = makeSoldier();
      final outcome = service.assign(slot, soldier);
      expect(outcome.isSuccess, isTrue);
      expect(outcome.hasMosMismatch, isTrue);
    });

    test('rank mismatch is flagged when soldier rank is below minimum', () {
      final slot = makeSlot(rank: AuthorizedRank.e7);
      final soldier = makeSoldier(rank: AuthorizedRank.e4);
      final outcome = service.assign(slot, soldier);
      expect(outcome.isSuccess, isTrue);
      expect(outcome.hasRankMismatch, isTrue);
    });

    test('no rank mismatch when soldier meets minimum rank', () {
      final slot = makeSlot();
      final soldier = makeSoldier(rank: AuthorizedRank.e6);
      final outcome = service.assign(slot, soldier);
      expect(outcome.isSuccess, isTrue);
      expect(outcome.hasRankMismatch, isFalse);
    });

    test('updated slot has correct personnel ID', () {
      final slot = makeSlot(slotId: 'slot-abc');
      final soldier = makeSoldier(id: 'soldier-xyz');
      final outcome = service.assign(slot, soldier);
      expect(outcome.updatedSlot?.assignedPersonnelId, 'soldier-xyz');
      expect(outcome.updatedSoldier?.assignedSlotId, 'slot-abc');
    });
  });

  // ---------------------------------------------------------------------------
  // unassign
  // ---------------------------------------------------------------------------

  group('unassign', () {
    test('unassigning from vacant slot returns unchanged slot', () {
      final slot = makeSlot();
      final outcome = service.unassign(slot, null);
      expect(outcome.updatedSlot.isVacant, isTrue);
      expect(outcome.updatedSoldier, isNull);
    });

    test('unassigning from filled slot clears assignment', () {
      final slot = makeSlot(assignedPersonnelId: 'p1');
      final soldier = makeSoldier(assignedSlotId: 's1');
      final outcome = service.unassign(slot, soldier);
      expect(outcome.updatedSlot.isVacant, isTrue);
      expect(outcome.updatedSoldier?.isUnassigned, isTrue);
    });

    test('unassigning with null soldier still clears slot', () {
      final slot = makeSlot(assignedPersonnelId: 'p1');
      final outcome = service.unassign(slot, null);
      expect(outcome.updatedSlot.isVacant, isTrue);
      expect(outcome.updatedSoldier, isNull);
    });
  });

  // ---------------------------------------------------------------------------
  // aggregateReadiness
  // ---------------------------------------------------------------------------

  group('aggregateReadiness', () {
    test('empty list returns grey', () {
      expect(service.aggregateReadiness([]), ReadinessColor.grey);
    });

    test('all FMC returns green', () {
      final soldiers = [
        makeSoldier(),
        makeSoldier(id: 'p2'),
      ];
      expect(service.aggregateReadiness(soldiers), ReadinessColor.green);
    });

    test('any NMC returns red', () {
      final soldiers = [
        makeSoldier(),
        makeSoldier(id: 'p2', readiness: ReadinessState.notMissionCapable),
      ];
      expect(service.aggregateReadiness(soldiers), ReadinessColor.red);
    });

    test('mixed FMC and PMC returns amber', () {
      final soldiers = [
        makeSoldier(),
        makeSoldier(id: 'p2', readiness: ReadinessState.partiallyMissionCapable),
      ];
      expect(service.aggregateReadiness(soldiers), ReadinessColor.amber);
    });

    test('single PMC soldier returns amber', () {
      final soldiers = [makeSoldier(readiness: ReadinessState.partiallyMissionCapable)];
      expect(service.aggregateReadiness(soldiers), ReadinessColor.amber);
    });
  });

  // ---------------------------------------------------------------------------
  // UnitNode fixture (used to verify UnitTreeService integration)
  // ---------------------------------------------------------------------------

  group('UnitTreeService integration via AssignmentService', () {
    test('validateReparent is accessible through treeService', () {
      const bde = UnitNode(
        unitId: 'bde',
        echelon: Echelon.brigade,
        branch: DoctrinalBranch.infantry,
        name: 'Brigade',
        isKeyLeader: false,
      );
      const bn = UnitNode(
        unitId: 'bn',
        echelon: Echelon.battalion,
        branch: DoctrinalBranch.infantry,
        name: 'Battalion',
        isKeyLeader: false,
        parentUnitId: 'bde',
      );
      final result = service.treeService.validateReparent(bn, bde, [bde, bn]);
      // bn (battalion) under bde (brigade) is valid
      expect(result.isValid, isTrue);
    });
  });
}