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Why did Sweden invade the Polish-Lithuanian Commonwealth in 1655?

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Map showing Poland's territory in 1634 under the reign of Wladyslaw IV Vasa, shaded in pink and spanning from the Baltic Sea in the north to near Kyiv in the southeast. Major present-day cities such as Warsaw, Krakow, Gdansk, Vilnius, Minsk, Lwow (Lviv), Pinsk, and Kyiv are marked within the territory, with surrounding cities like Moscow, Riga, Vienna, and Budapest shown for reference. — Polish-Lithuanian Commonwealth Poland's territory in 1634, during the reign of Władysław IV Vasa.

Sweden’s invasion of the Polish-Lithuanian Commonwealth in 1655, which initiated the First Northern War, was driven by several strategic and political motivations under King Charles X Gustav:

Geopolitical Strategy: Charles X aimed to secure Sweden’s dominance in the Baltic region, which he sought to turn into a "Swedish lake." He was particularly concerned that the expansion of Muscovy would upset the regional balance of power.12
Pretext for War: The Swedish king used the refusal of King John II Casimir Vasa to renounce his claims to the Swedish throne as a formal justification for hostilities.2
Economic and Territorial Ambitions: Initially, Sweden sought to seize Polish and Prussian harbors. However, following early military successes, Charles X expanded his goals to include gaining the Polish crown and achieving total mastery over the Commonwealth.2

While the invasion was initially successful, it eventually triggered a broad international coalition against Sweden, leading to the Treaty of Oliwa in 1660, which restored the pre-war territorial status quo.12