package authentication

import (
	"context"
	"crypto/rand"
	"errors"
	"fmt"
	"ruben/inventory2/internal/consts"
	"time"

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

// NewState creates a new state for logging in, saving it in the database.
func (a *Authenticator) NewState(ctx context.Context, targetURI string) ([32]byte, error) {
	state, err := generateRandomState()
	if err != nil {
		return state, fmt.Errorf("failed to generate random state: %w", err)
	}

	if _, err = a.db.Exec(
		ctx,
		`
			INSERT INTO
				oauth_login_states (
					state,
					target_uri
				)
			VALUES (
				@state,
				@target_uri
			)
		`,
		pgx.NamedArgs{
			"state":      state[:],
			"target_uri": targetURI,
		},
	); err != nil {
		return state, fmt.Errorf("failed to execute query: %w", err)
	}

	return state, nil
}

func generateRandomState() ([32]byte, error) {
	var b [32]byte
	_, err := rand.Read(b[:])
	return b, err
}

// GetStateExpirationAndURL get's the oauth state's expiration
func (a *Authenticator) GetStateExpirationAndURL(ctx context.Context, state string) (time.Time, string, error) {
	rows, err := a.db.Query(
		ctx,
		`
			SELECT
				expiration,
				target_uri
			FROM
				oauth_login_states
			WHERE
				state = ('\x' || @state)::BYTEA`,
		pgx.NamedArgs{
			"state": state,
		},
	)
	if err != nil {
		return time.Time{}, "", fmt.Errorf("failed to perform query: %w", err)
	}

	type Row struct {
		Expiration time.Time
		Target_uri pgtype.Text
	}

	r, err := pgx.CollectExactlyOneRow(rows, pgx.RowToStructByNameLax[Row])
	if err != nil {
		if errors.Is(err, pgx.ErrNoRows) {
			return time.Time{}, "", consts.ErrNotFound
		}

		return time.Time{}, "", fmt.Errorf("failed to scan row: %w", err)
	}

	return r.Expiration, r.Target_uri.String, nil
}

// TODO: need to automatically clean up expired tokens
func (a *Authenticator) DeleteOAuthTokens(ctx context.Context, accessToken string) error {
	_, err := a.db.Exec(ctx, "DELETE FROM oauth_tokens WHERE access_token = @access_token", pgx.NamedArgs{"access_token": accessToken})
	if err != nil {
		return fmt.Errorf("failed to perform query: %w", err)
	}
	return nil
}

func (a *Authenticator) GetAccessTokenClaimsAndExpiration(ctx context.Context, accessToken string) (claims AccessTokenClaims, expiration time.Time, err error) {
	rows, err := a.db.Query(
		ctx,
		`
			SELECT
				expiry,

				id_token_custom_claims_name,
				id_token_custom_claims_picture,
				id_token_custom_claims_nickname,
				id_token_custom_claims_given_name,
				id_token_custom_claims_family_name,
				id_token_custom_claims_updated_at

			FROM
				oauth_tokens
			WHERE
				access_token = @access_token
		`,
		pgx.NamedArgs{
			"access_token": accessToken,
		},
	)
	if err != nil {
		return AccessTokenClaims{}, time.Time{}, fmt.Errorf("failed to perform query: %w", err)
	}

	type Row struct {
		Expiry                             time.Time
		Id_token_custom_claims_name        string
		Id_token_custom_claims_picture     string
		Id_token_custom_claims_nickname    string
		Id_token_custom_claims_given_name  string
		Id_token_custom_claims_family_name string
		Id_token_custom_claims_updated_at  time.Time
	}

	r, err := pgx.CollectExactlyOneRow(rows, pgx.RowToStructByNameLax[Row])
	if err != nil {
		if errors.Is(err, pgx.ErrNoRows) {
			return AccessTokenClaims{}, time.Time{}, consts.ErrNotFound
		}
		return AccessTokenClaims{}, time.Time{}, fmt.Errorf("failed to scan row: %w", err)
	}

	claims.Name = r.Id_token_custom_claims_name
	claims.Picture = r.Id_token_custom_claims_picture
	claims.Nickname = r.Id_token_custom_claims_nickname
	claims.GivenName = r.Id_token_custom_claims_given_name
	claims.FamilyName = r.Id_token_custom_claims_family_name
	claims.UpdatedAt = r.Id_token_custom_claims_updated_at

	return claims, r.Expiry, nil
}

func (a *Authenticator) getRefreshTokenForAccessToken(ctx context.Context, accessToken string) (refreshToken, tokenType string, err error) {
	rows, err := a.db.Query(
		ctx,
		`
			SELECT
				refresh_token,
				token_type
			FROM
				oauth_tokens
			WHERE
				access_token = @access_token
		`,
		pgx.NamedArgs{
			"access_token": accessToken,
		},
	)
	if err != nil {
		return "", "", fmt.Errorf("failed to perform query: %w", err)
	}

	type Row struct {
		Refresh_token string
		Token_type    string
	}

	r, err := pgx.CollectExactlyOneRow(rows, pgx.RowToStructByNameLax[Row])
	if err != nil {
		if errors.Is(err, pgx.ErrNoRows) {
			return "", "", consts.ErrNotFound
		}
		return "", "", fmt.Errorf("failed to scan row: %w", err)
	}

	return r.Refresh_token, r.Token_type, nil
}