package imap

import (
	"context"

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

type folderSyncState struct {
	FolderID      string
	UIDValidity   uint32
	HighestModSeq uint64
	LastUID       uint32
}

func loadFolderSyncState(ctx context.Context, db *pgxpool.Pool, accountID, remoteName string) (folderSyncState, bool, error) {
	var state folderSyncState
	err := db.QueryRow(ctx, `
		SELECT id, uidvalidity, highest_modseq, last_uid
		FROM mail_folders
		WHERE account_id = $1 AND remote_name = $2
	`, accountID, remoteName).Scan(&state.FolderID, &state.UIDValidity, &state.HighestModSeq, &state.LastUID)
	if err != nil {
		return folderSyncState{}, false, err
	}
	return state, true, nil
}

func saveFolderSyncState(ctx context.Context, db *pgxpool.Pool, folderID string, uidValidity uint32, highestModSeq uint64, lastUID uint32, messageCount int) error {
	_, err := db.Exec(ctx, `
		UPDATE mail_folders
		SET uidvalidity = $2,
		    highest_modseq = $3,
		    last_uid = $4,
		    message_count = $5,
		    updated_at = NOW()
		WHERE id = $1
	`, folderID, uidValidity, highestModSeq, lastUID, messageCount)
	return err
}

func resetFolderMessages(ctx context.Context, db *pgxpool.Pool, folderID string) error {
	_, err := db.Exec(ctx, `DELETE FROM messages WHERE folder_id = $1`, folderID)
	return err
}

// resetAccountSyncCursors zeroes last_uid and highest_modseq for all folders
// of an account so the next sync re-fetches every message from the IMAP server.
// Existing messages are kept; ON CONFLICT DO UPDATE overwrites body_html.
func resetAccountSyncCursors(ctx context.Context, db *pgxpool.Pool, accountID string) error {
	_, err := db.Exec(ctx, `
		UPDATE mail_folders
		SET last_uid = 0, highest_modseq = 0, updated_at = NOW()
		WHERE account_id = $1
	`, accountID)
	return err
}