In a small university's literature department, three professors, Dakarai, Hermine, and Xin, decide to organize a surprise farewell party for a beloved colleague, Valentina, who is retiring at the end of the academic year. Valentina is known for her love of detective novels, and therefore, the trio plans a detective-themed party. To maintain secrecy, Dakarai, who is spearheading the effort, instructs Hermine and Xin not to mention anything to Valentina or to any other colleague who might inadvertently spill the beans. 

Hermine is tasked with arranging the food and decorations. A few days into the planning, she meets another professor, Leif, in the corridor. Leif, unaware of the surprise, mentions his concern about not having an appropriate send-off for Valentina. Hermine realizes that Leif might plan his own farewell for Valentina, risking their surprise. To prevent duplication without betraying the secret, she assures Leif that a proper farewell will be organized but refrains from disclosing any details.

Xin is responsible for compiling a goodbye message book, collecting notes from all of Valentina's current and past colleagues. Intent on preserving the secret, Xin reaches out to retired professor Anika, who lives abroad, to ask for her contribution. During the conversation, Anika expresses her hope to attend the farewell personally, as she has planned a visit that coincides with the end of the academic year. Xin, careful not to reveal the secret party, encourages Anika to visit around that time, hinting it would be worth her while. 

A week before the planned event, Dakarai realizes he had overlooked inviting the dean of the university, who should be present at such a significant occasion. The dean, Zephyr, has a reputation for being exceptionally close-mouthed, so Dakarai is confident the secret will be safe with him. Dakarai sends Zephyr a private message to extend the invitation.

The day before the surprise party, Valentina runs into Anika, who has just arrived in town. Valentina is surprised by the visit. During their conversation, Anika has to tread carefully to avoid giving away the surprise, as she assumes Valentina is unaware of the event. Meanwhile, Leif still believes no plans have been made for Valentina's farewell. Zephyr is the only one outside the organizers who knows about the surprise.

Given this complex scenario, could you determine who knows and doesn't know about the surprise party?
In this scenario, there are three main groups involved with different levels of knowledge regarding the surprise farewell party for Valentina: the organizers (Dakarai, Hermine, Xin), the unsuspecting professor (Leif), and the individual who was informed directly by an organizer (Dean Zephyr). Additionally, there are two individuals whose awareness of the party is somewhat nebulous: Anika, who has been informed something is planned without details, and Valentina, the guest of honor, presumed to be unaware of the event.

Dakarai, Hermine, and Xin are fully aware of the surprise party, as they are the primary organizers. Dakarai's role includes overall coordination and inviting the dean; Hermine's role involves arranging food and decorations; Xin's role encompasses compiling the message book and subtly inviting outside contributors, like Anika.

Leif only knows that some form of a farewell will happen, but he does not have the specifics. Hermine assured him that a proper farewell was being planned, without disclosing it was a surprise party.

Dean Zephyr is aware of the party because Dakarai, who trusts Zephyr's discretion, sent him a private invitation. Zephyr's knowledge is complete concerning the event's nature and the intent to keep it a surprise for Valentina.

Anika knows something is being planned around the time of her visit, as hinted by Xin, but she does not explicitly know it is a surprise party for Valentina. Xin's intention was to ensure Anika would attend the party without revealing its surprise nature.

Valentina is intended to be the only completely unaware party; all plans have been made with her lack of knowledge in mind. There have been careful steps taken by the organizers to prevent her from finding out, such as instructing Hermine, Xin, and Zephyr to keep the details from her. However, even though Anika and Valentina have met and talked, there is no information provided that Anika has disclosed the secret, so the assumption is that Anika has managed to keep the surprise party a secret.

Finally, regarding who knows and who doesn't know about the surprise farewell party for Valentina: 
- Dakarai, Hermine, Xi, and Zephyr know about the party.
- Leif and Anika know that a farewell event is planned, but they do not know it is a surprise party.
- Valentina is presumed to not know about the party at all, as everyone involved has been cautious to keep the party a secret from her.