package database

import (
	"Portifolio/internal/model"
	"database/sql"
	"fmt"

	_ "github.com/mattn/go-sqlite3"
)

func GetTrades(db *sql.DB) ([]model.Trade, error) {
	rows, err := db.Query("SELECT symbol, currency_code, shares, product, type, price, traded_at FROM trades")
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var trades []model.Trade
	for rows.Next() {
		var typeInt int
		var t model.Trade

		err := rows.Scan(&t.Symbol, &t.CurrencyCode, &t.Shares, &t.Product, &typeInt, &t.Price, &t.Date)
		if err != nil {
			return nil, err
		}

		switch typeInt {
		case 0:
			t.Type = model.TradeType(false)
		case 1:
			t.Type = model.TradeType(true)
		default:
			return nil, fmt.Errorf("failed to convert given Type int to bool of trade type.")
		}

		trades = append(trades, t)
	}
	if err = rows.Err(); err != nil {
		return nil, err
	}
	return trades, nil
}

func GetPositions(db *sql.DB) ([]model.Position, error) {
	rows, err := db.Query("SELECT company_id, symbol, shares, weight, cost_basis, currency_id, currency_code from position")
	if err != nil {
		return []model.Position{}, err
	}
	defer rows.Close()

	var positions []model.Position
	for rows.Next() {
		var t model.Position

		err := rows.Scan(&t.CompanyID, &t.Symbol, &t.Shares, &t.Weight, &t.CostBasis, &t.CurrencyID, &t.CurrencyCode)
		if err != nil {
			return []model.Position{}, err
		}

		positions = append(positions, t)
	}
	if err = rows.Err(); err != nil {
		return []model.Position{}, err
	}

	return positions, nil
}

func InsertTrade(db *sql.DB, trade model.Trade) error {
	_, err := db.Exec(
		"INSERT INTO trades (symbol, currency_code, shares, product, type, price, traded_at) VALUES (?, ?, ?, ?, ?, ?, ?)",
		trade.Symbol,
		trade.CurrencyCode,
		trade.Shares,
		trade.Product,
		trade.Type,
		trade.Price,
		trade.Date,
	)
	return err
}

func UpdatePositions(db *sql.DB, positions []model.Position) error {
	// Complete overwrite of the db positions
	_, err := db.Exec("DELETE FROM position")
	if err != nil {
		return fmt.Errorf("failed to clear positions: %s", err)
	}

	for _, p := range positions {
		// Resolve company_id if missing
		if p.CompanyID == 0 {
			company, err := GetCompanyBySymbol(db, p.Symbol)
			if err != nil {
				return fmt.Errorf("could not find company %s: %s", p.Symbol, err)
			}
			p.CompanyID = company.ID
		}

		// Resolve currency_id if missing
		if p.CurrencyID == 0 {
			currency, err := GetCurrencyByCode(db, p.CurrencyCode)
			if err != nil {
				return fmt.Errorf("could not find currency %s: %s", p.CurrencyCode, err)
			}
			p.CurrencyID = currency.ID
		}

		_, err := db.Exec(`
            INSERT INTO position (company_id, symbol, currency_id, currency_code, shares, weight, cost_basis)
            VALUES (?, ?, ?, ?, ?, ?, ?)
            ON CONFLICT(company_id) DO UPDATE SET
                symbol        = excluded.symbol,
                currency_id   = excluded.currency_id,
                currency_code = excluded.currency_code,
                shares        = excluded.shares,
                weight        = excluded.weight,
                cost_basis    = excluded.cost_basis
        `,
			p.CompanyID,
			p.Symbol,
			p.CurrencyID,
			p.CurrencyCode,
			p.Shares,
			p.Weight,
			p.CostBasis,
		)
		if err != nil {
			return fmt.Errorf("failed to upsert position %s: %s", p.Symbol, err)
		}
	}

	return nil
}