package tariff

import (
	"context"
	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/bson/primitive"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"
	"go.uber.org/zap"
	"gitea.pena/PenaSide/tariffs/internal/errors"
	"gitea.pena/PenaSide/tariffs/internal/models"
	"math"
	"time"
)

type Deps struct {
	Mdb         *mongo.Collection
	Logger      *zap.Logger
	PrivilegeDB *mongo.Collection
}

type Tariff struct {
	mdb         *mongo.Collection
	logger      *zap.Logger
	privilegeDB *mongo.Collection
}

func NewTariffRepo(deps Deps) *Tariff {
	return &Tariff{
		mdb:         deps.Mdb,
		logger:      deps.Logger,
		privilegeDB: deps.PrivilegeDB,
	}
}

func (t *Tariff) GetByID(ctx context.Context, id primitive.ObjectID) (models.Tariff, error) {
	var tariff models.Tariff
	filter := bson.M{
		"_id":       id,
		"isDeleted": false,
	}

	err := t.mdb.FindOne(ctx, filter).Decode(&tariff)
	if err != nil {
		if err == mongo.ErrNoDocuments {
			return tariff, errors.ErrNotFound
		}
		t.logger.Error("failed to get tariff by object id", zap.Error(err))
		return tariff, err
	}

	return tariff, nil
}

func (t *Tariff) Create(ctx context.Context, req models.Tariff) (models.Tariff, error) {
	req.ID = primitive.NewObjectID()
	req.CreatedAt = time.Now()
	req.IsDeleted = false
	req.UpdatedAt = time.Now()

	_, err := t.mdb.InsertOne(ctx, req)
	if err != nil {
		t.logger.Error("failed insert tariff", zap.Error(err))
		return req, err
	}

	return req, nil
}

func (t *Tariff) GetList(ctx context.Context, page, limit int64, userID string) (models.TariffPagination, error) {
	var result models.TariffPagination
	filter := bson.M{
		"$or": []bson.M{
			{"isCustom": false, "isDeleted": false},
		},
	}
	if userID != "" {
		filter["$or"] = append(filter["$or"].([]bson.M), bson.M{"isCustom": true, "userID": userID})
	}

	count, err := t.mdb.CountDocuments(ctx, filter)
	if err != nil {
		t.logger.Error("failed count tariffs", zap.Error(err))
		return result, err
	}

	totalPages := int(math.Ceil(float64(count) / float64(limit)))
	offset := (page - 1) * limit
	findOptions := options.Find().SetSort(bson.D{{"order", 1}}).SetSkip(offset).SetLimit(limit)

	cursor, err := t.mdb.Find(ctx, filter, findOptions)
	if err != nil {
		t.logger.Error("failed find tariffs", zap.Error(err))
		return result, err
	}
	defer cursor.Close(ctx)

	var tariffs []models.Tariff
	if err = cursor.All(ctx, &tariffs); err != nil {
		t.logger.Error("failed decode tariffs", zap.Error(err))
		return result, err
	}

	result.TotalPages = totalPages
	result.Tariffs = tariffs

	return result, nil
}

func (t *Tariff) SoftDelete(ctx context.Context, tariffID primitive.ObjectID) (models.Tariff, error) {
	var tariff models.Tariff
	filter := bson.M{"_id": tariffID}
	update := bson.M{"$set": bson.M{"isDeleted": true, "deletedAt": time.Now()}}
	err := t.mdb.FindOneAndUpdate(ctx, filter, update, options.FindOneAndUpdate().SetReturnDocument(options.After)).Decode(&tariff)
	if err != nil {
		if err == mongo.ErrNoDocuments {
			return tariff, errors.ErrNotFound
		}
		t.logger.Error("failed soft delete tariff", zap.Error(err))
		return tariff, err
	}

	return tariff, nil
}

func (t *Tariff) Update(ctx context.Context, tariffID primitive.ObjectID, req models.Tariff) (models.Tariff, error) {
	var tariff models.Tariff
	err := t.mdb.FindOne(ctx, bson.M{"_id": tariffID}).Decode(&tariff)
	if err != nil {
		if err == mongo.ErrNoDocuments {
			return tariff, errors.ErrNotFound
		}
		t.logger.Error("failed find tariff", zap.Error(err))
		return tariff, err
	}

	privilegeIDs := make([]string, len(req.Privileges))
	for i, privilege := range req.Privileges {
		privilegeIDs[i] = privilege.PrivilegeID
	}

	cursor, err := t.privilegeDB.Find(ctx, bson.M{"privilegeId": bson.M{"$in": privilegeIDs}})
	if err != nil {
		t.logger.Error("failed find privileges", zap.Error(err))
		return tariff, err
	}
	defer cursor.Close(ctx)

	privilegeMap := make(map[string]models.Privilege)
	for cursor.Next(ctx) {
		var privilege models.Privilege
		if err := cursor.Decode(&privilege); err != nil {
			t.logger.Error("failed decode privilege", zap.Error(err))
			return tariff, err
		}
		privilegeMap[privilege.PrivilegeID] = privilege
	}

	clean := make([]models.Privilege, len(req.Privileges))
	for i, privilege := range req.Privileges {
		origPrivilege := privilegeMap[privilege.PrivilegeID]
		clean[i] = models.Privilege{
      ID:          origPrivilege.ID,
			Name:        origPrivilege.Name,
			PrivilegeID: origPrivilege.PrivilegeID,
			ServiceKey:  origPrivilege.ServiceKey,
			Description: origPrivilege.Description,
			Type:        origPrivilege.Type,
			Value:       origPrivilege.Value,
      Amount:      origPrivilege.Amount,
			Price:       origPrivilege.Price,
		}
	}

	update := bson.M{
		"$set": bson.M{
      "description": req.Description,
			"order":      req.Order,
			"name":       req.Name,
			"price":      req.Price,
			"isCustom":   req.IsCustom,
			"privileges": clean,
		},
	}

	err = t.mdb.FindOneAndUpdate(ctx, bson.M{"_id": tariffID}, update).Decode(&tariff)
	if err != nil {
		if err == mongo.ErrNoDocuments {
			return tariff, errors.ErrNotFound
		}
		t.logger.Error("failed update tariff", zap.Error(err))
		return tariff, err
	}

	return tariff, nil
}

func (t *Tariff) Restore(ctx context.Context, tariffID primitive.ObjectID) (models.Tariff, error) {
	var tariff models.Tariff

	filter := bson.M{"_id": tariffID}
	update := bson.M{"$set": bson.M{"isDeleted": false}}
	err := t.mdb.FindOneAndUpdate(ctx, filter, update, options.FindOneAndUpdate().SetReturnDocument(options.After)).Decode(&tariff)
	if err != nil {
		if err == mongo.ErrNoDocuments {
			return tariff, errors.ErrNotFound
		}
		t.logger.Error("failed restore tariff", zap.Error(err))
		return tariff, err
	}

	return tariff, nil
}