package posts

import (
	"context"
	"database/sql"

	"backend/app/requests"
	"backend/database"
	"backend/database/models/qvyun_v2/public/model"
	"backend/database/models/qvyun_v2/public/table"
	"backend/providers/otel"

	. "github.com/go-jet/jet/v2/postgres"
	"github.com/samber/lo"
	log "github.com/sirupsen/logrus"
	"go.opentelemetry.io/otel/attribute"
	semconv "go.opentelemetry.io/otel/semconv/v1.4.0"
)

// @provider:except
type Service struct {
	db  *sql.DB
	log *log.Entry `inject:"false"`
}

func (svc *Service) Prepare() error {
	svc.log = log.WithField("module", "posts.service")
	_ = Int(1)
	return nil
}

// GetBoughtPosts
func (svc *Service) GetBoughtPosts(ctx context.Context, pagination *requests.Pagination, filter *UserPostFilter) ([]model.Posts, int64, error) {
	_, span := otel.Start(ctx, "users.service.GetBoughtPosts")
	defer span.End()
	span.SetAttributes(
		attribute.Int64("user.id", filter.UserID),
		attribute.Int64("page.page", pagination.Page),
		attribute.Int64("page.limit", pagination.Limit),
	)
	tbl := table.Posts

	boughtIds, err := svc.GetUserBoughtIDs(ctx, filter.TenantID, filter.UserID)
	if err != nil {
		return nil, 0, err
	}

	if len(boughtIds) == 0 {
		return nil, 0, nil
	}

	idExprs := lo.Map(boughtIds, func(id int64, _ int) Expression { return Int64(id) })

	cond := tbl.ID.IN(
		idExprs...,
	).AND(
		tbl.TenantID.EQ(Int64(filter.TenantID)),
	).AND(
		tbl.UserID.EQ(Int64(filter.UserID)),
	)

	if filter.CreatedAt != nil {
		cond = cond.AND(tbl.CreatedAt.LT_EQ(TimestampT(*filter.CreatedAt)))
	}

	if filter.Keyword != nil {
		cond = cond.AND(
			tbl.Title.
				LIKE(String(database.WrapLike(*filter.Keyword))).
				OR(
					tbl.Description.LIKE(String(database.WrapLike(*filter.Keyword))),
				).
				OR(
					tbl.Content.LIKE(String(database.WrapLike(*filter.Keyword))),
				),
		)
	}

	cntStmt := tbl.SELECT(COUNT(tbl.ID).AS("cnt")).WHERE(cond)
	span.SetAttributes(semconv.DBStatementKey.String(cntStmt.DebugSql()))

	var count struct {
		Cnt int64
	}
	if err := cntStmt.QueryContext(ctx, svc.db, &count); err != nil {
		return nil, 0, err
	}

	stmt := tbl.
		SELECT(tbl.AllColumns).
		ORDER_BY(tbl.ID.DESC()).
		LIMIT(pagination.Limit).
		OFFSET(pagination.Offset())
	span.SetAttributes(semconv.DBStatementKey.String(stmt.DebugSql()))

	var posts []model.Posts
	if err := stmt.QueryContext(ctx, svc.db, &posts); err != nil {
		return nil, 0, err
	}

	return posts, count.Cnt, nil
}

// GetPosts
func (svc *Service) GetPosts(ctx context.Context, pagination *requests.Pagination, filter *UserPostFilter) ([]model.Posts, int64, error) {
	_, span := otel.Start(ctx, "users.service.GetPosts")
	defer span.End()
	span.SetAttributes(
		attribute.Int64("user.id", filter.UserID),
		attribute.Int64("page.page", pagination.Page),
		attribute.Int64("page.limit", pagination.Limit),
	)
	tbl := table.Posts

	cond := Bool(true)
	if filter.ID != nil {
		cond = cond.AND(tbl.ID.EQ(Int64(*filter.ID)))
	}
	if filter.UserID != 0 {
		cond = cond.AND(tbl.UserID.EQ(Int64(filter.UserID)))
	}
	if filter.CreatedAt != nil {
		cond = cond.AND(tbl.CreatedAt.LT_EQ(TimestampT(*filter.CreatedAt)))
	}
	if filter.TenantID != 0 {
		cond = cond.AND(tbl.TenantID.EQ(Int64(filter.TenantID)))
	}
	if filter.Keyword != nil {
		cond = cond.AND(
			tbl.Title.
				LIKE(String(database.WrapLike(*filter.Keyword))).
				OR(
					tbl.Description.LIKE(String(database.WrapLike(*filter.Keyword))),
				).
				OR(
					tbl.Content.LIKE(String(database.WrapLike(*filter.Keyword))),
				),
		)
	}

	cntStmt := tbl.SELECT(COUNT(tbl.ID).AS("cnt")).WHERE(cond)
	span.SetAttributes(semconv.DBStatementKey.String(cntStmt.DebugSql()))

	var count struct {
		Cnt int64
	}
	if err := cntStmt.QueryContext(ctx, svc.db, &count); err != nil {
		return nil, 0, err
	}

	stmt := tbl.
		SELECT(tbl.AllColumns).
		ORDER_BY(tbl.ID.DESC()).
		LIMIT(pagination.Limit).
		OFFSET(pagination.Offset())
	span.SetAttributes(semconv.DBStatementKey.String(stmt.DebugSql()))

	var posts []model.Posts
	if err := stmt.QueryContext(ctx, svc.db, &posts); err != nil {
		return nil, 0, err
	}

	return posts, count.Cnt, nil
}

// GetPostByHash
func (svc *Service) GetPostByHash(ctx context.Context, tenantID int64, hash string) (*model.Posts, error) {
	_, span := otel.Start(ctx, "users.service.GetPostByHash")
	defer span.End()
	span.SetAttributes(
		attribute.String("hash", hash),
	)
	tbl := table.Posts

	stmt := tbl.
		SELECT(tbl.AllColumns).
		WHERE(
			tbl.Hash.EQ(String(hash)).AND(
				tbl.TenantID.EQ(Int64(tenantID)),
			),
		)
	span.SetAttributes(semconv.DBStatementKey.String(stmt.DebugSql()))

	var post model.Posts
	if err := stmt.QueryContext(ctx, svc.db, &post); err != nil {
		return nil, err
	}

	return &post, nil
}

// GetUserBoughtPosts
func (svc *Service) GetUserBoughtIDs(ctx context.Context, tenantID, userID int64) ([]int64, error) {
	_, span := otel.Start(ctx, "users.service.GetUserBoughtIDs")
	defer span.End()
	span.SetAttributes(
		attribute.Int64("tenant.id", tenantID),
		attribute.Int64("user.id", userID),
	)
	tbl := table.UserBoughtPosts

	stmt := tbl.
		SELECT(tbl.PostID.AS("post_id")).
		WHERE(
			tbl.TenantID.EQ(Int64(tenantID)).AND(
				tbl.UserID.EQ(Int64(userID)),
			),
		)
	span.SetAttributes(semconv.DBStatementKey.String(stmt.DebugSql()))
	type tmp struct {
		PostID int64
	}

	var results []tmp
	if err := stmt.QueryContext(ctx, svc.db, &results); err != nil {
		return nil, err
	}

	return lo.Map(results, func(item tmp, _ int) int64 {
		return item.PostID
	}), nil
}