package meteo

import (
	"context"
	"fmt"

	b "github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgxpool"
)

type Repository interface {
	InsertMeteoDataTX(ctx context.Context, accepted []MeteoData, rejected []RejectedMeteoData) (int, int, error)
}

type pgxRepo struct {
	*pgxpool.Pool
}

func NewPGXRepo(pool *pgxpool.Pool) Repository {
	return &pgxRepo{
		pool,
	}
}

const insertAcceptedMeteoData = `insert into public.meteo_data (location_name, max_temp, min_temp, rainfall, cloudiness, created_at) values ($1, $2, $3, $4, $5, $6) returning id`

func (pgx *pgxRepo) InsertMeteoDataTX(ctx context.Context, accepted []MeteoData, rejected []RejectedMeteoData) (int, int, error) {
	tx, err := pgx.Begin(ctx)
	if err != nil {
		return 0, 0, fmt.Errorf("error starting transaction: %w", err)
	}
	defer tx.Rollback(ctx)

	acceptedCount, err := pgx.insertAcceptedMeteoData(ctx, tx, accepted)
	if err != nil {
		return 0, 0, err
	}

	rejectedCount, err := pgx.insertRejectedMeteoData(ctx, tx, rejected)
	if err != nil {
		return 0, 0, err
	}

	if err = tx.Commit(ctx); err != nil {
		return 0, 0, fmt.Errorf("error committing transaction: %w", err)
	}

	return acceptedCount, rejectedCount, nil
}

func (pgx *pgxRepo) insertAcceptedMeteoData(ctx context.Context, tx b.Tx, data []MeteoData) (int, error) {
	if len(data) == 0 {
		return 0, nil
	}

	batch := &b.Batch{}

	for _, d := range data {
		batch.Queue(insertAcceptedMeteoData, d.Location, d.MaxTemp, d.MinTemp, d.Rainfall, d.Cloudiness, d.Timestamp)
	}

	results := tx.SendBatch(ctx, batch)

	var rowsInserted int
	for i := range data {
		_, err := results.Exec()
		rowsInserted++
		if err != nil {
			results.Close()
			return 0, fmt.Errorf("error executing batch command %d: %w", i, err)
		}
	}

	results.Close()

	return rowsInserted, nil
}

const insertRejectedMeteoData = `insert into public.rejected_data (raw_data, reason) values ($1, $2) returning id`

func (pgx *pgxRepo) insertRejectedMeteoData(ctx context.Context, tx b.Tx, data []RejectedMeteoData) (int, error) {
	if len(data) == 0 {
		return 0, nil
	}

	batch := &b.Batch{}

	for _, d := range data {
		batch.Queue(insertRejectedMeteoData, d.RowValue, d.Reason)
	}

	results := tx.SendBatch(ctx, batch)

	var rowsInserted int
	for i := range data {
		_, err := results.Exec()
		rowsInserted++
		if err != nil {
			results.Close()
			return 0, fmt.Errorf("error executing batch command %d: %w", i, err)
		}
	}

	results.Close()

	return rowsInserted, nil
}