package repository

import (
	"context"
	"git.sch9.ru/new_gate/ms-tester/internal/models"
	"github.com/jmoiron/sqlx"
)

type ProblemRepository struct {
	db *sqlx.DB
	//logger *zap.Logger
}

func NewProblemRepository(db *sqlx.DB) *ProblemRepository {
	return &ProblemRepository{
		db: db,
		//logger: logger,
	}
}

const createProblemQuery = "INSERT INTO problems (title) VALUES (?) RETURNING id"

func (r *ProblemRepository) CreateProblem(ctx context.Context, title string) (int32, error) {
	const op = "ProblemRepository.CreateProblem"

	query := r.db.Rebind(createProblemQuery)
	rows, err := r.db.QueryxContext(ctx, query, title)
	if err != nil {
		return 0, handlePgErr(err, op)
	}

	defer rows.Close()
	var id int32
	rows.Next()
	err = rows.Scan(&id)
	if err != nil {
		return 0, handlePgErr(err, op)
	}

	return id, nil
}

const readProblemQuery = "SELECT * from problems WHERE id=? LIMIT 1"

func (r *ProblemRepository) ReadProblemById(ctx context.Context, id int32) (*models.Problem, error) {
	const op = "ProblemRepository.ReadProblemById"

	var problem models.Problem
	query := r.db.Rebind(readProblemQuery)
	err := r.db.GetContext(ctx, &problem, query, id)
	if err != nil {
		return nil, handlePgErr(err, op)
	}
	return &problem, nil
}

const deleteProblemQuery = "DELETE FROM problems WHERE id=?"

func (r *ProblemRepository) DeleteProblem(ctx context.Context, id int32) error {
	const op = "ProblemRepository.DeleteProblem"

	query := r.db.Rebind(deleteProblemQuery)
	_, err := r.db.ExecContext(ctx, query, id)
	if err != nil {
		return handlePgErr(err, op)
	}

	return nil
}

const (
	ListProblemsQuery = `SELECT id, title, time_limit, memory_limit, created_at, updated_at
FROM problems
LIMIT ? OFFSET ?`
	CountProblemsQuery = "SELECT COUNT(*) FROM problems"
)

func (r *ProblemRepository) ListProblems(ctx context.Context, page int32, pageSize int32) ([]*models.ProblemListItem, int32, error) {
	const op = "ContestRepository.ListProblems"

	if pageSize > 20 || pageSize < 1 {
		pageSize = 1
	}

	var problems []*models.ProblemListItem
	query := r.db.Rebind(ListProblemsQuery)
	err := r.db.SelectContext(ctx, &problems, query, pageSize, (page-1)*pageSize)
	if err != nil {
		return nil, 0, handlePgErr(err, op)
	}

	var count int32
	err = r.db.GetContext(ctx, &count, CountProblemsQuery)
	if err != nil {
		return nil, 0, handlePgErr(err, op)
	}

	return problems, count, nil
}