package main

import (
	"context"
	"fmt"
	"time"

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

// DB wraps a pgx connection pool for writing energy data.
type DB struct {
	pool *pgxpool.Pool
}

func NewDB(ctx context.Context, dsn string) (*DB, error) {
	pool, err := pgxpool.New(ctx, dsn)
	if err != nil {
		return nil, fmt.Errorf("pgxpool: %w", err)
	}
	if err := pool.Ping(ctx); err != nil {
		return nil, fmt.Errorf("db ping: %w", err)
	}
	return &DB{pool: pool}, nil
}

func (db *DB) WriteInverter(ctx context.Context, t time.Time, d *InverterData) error {
	_, err := db.pool.Exec(ctx, `
		INSERT INTO inverter
			(time, pv1_power, pv2_power, pv_l1_power, pv_l2_power, pv_l3_power,
			 battery_soc, grid_import_kwh, grid_export_kwh, pv_energy_kwh)
		VALUES ($1,$2,$3,$4,$5,$6,$7,$8,$9,$10)`,
		t,
		d.Pv1Power, d.Pv2Power,
		d.PvL1Power, d.PvL2Power, d.PvL3Power,
		d.BatterySoC,
		d.GridImportKwh, d.GridExportKwh, d.PvEnergyKwh,
	)
	return err
}

func (db *DB) WriteMeter(ctx context.Context, t time.Time, r MeterReading) error {
	_, err := db.pool.Exec(ctx, `
		INSERT INTO power_meter (time, device, l1_power, l2_power, l3_power, import_kwh, export_kwh)
		VALUES ($1,$2,$3,$4,$5,$6,$7)`,
		t, r.Device,
		r.L1Power, r.L2Power, r.L3Power,
		r.ImportKwh, r.ExportKwh,
	)
	return err
}

func (db *DB) WriteCharger(ctx context.Context, r ChargerReading) error {
	_, err := db.pool.Exec(ctx,
		`INSERT INTO charger (time, power, eto_wh) VALUES ($1, $2, $3)`,
		r.Time, r.Power, r.EtoWh,
	)
	return err
}

func (db *DB) Close() {
	db.pool.Close()
}