AzooKeyKanaKanjiConverter/Sources/KanaKanjiConverterModule/ConversionAlgorithms/Zenzai/Zenz/Zenz.swift

package import Foundation
import SwiftUtils
import EfficientNGram

private func debugLog(_ items: Any..., separator: String = " ", terminator: String = "\n") {
    let message = items.map { "\($0)" }.joined(separator: separator) + terminator
    let timestamp = ISO8601DateFormatter().string(from: Date())
    let logEntry = "[\(timestamp)] \(message)"
    
    print(logEntry, terminator: "")
    debug(message)
    
    let debugLogFile = FileManager.default.temporaryDirectory.appendingPathComponent("zenz_debug_\(ProcessInfo.processInfo.processIdentifier).log")
    if let data = logEntry.data(using: .utf8) {
        if !FileManager.default.fileExists(atPath: debugLogFile.path) {
            FileManager.default.createFile(atPath: debugLogFile.path, contents: data)
        } else {
            if let fileHandle = try? FileHandle(forWritingTo: debugLogFile) {
                fileHandle.seekToEndOfFile()
                fileHandle.write(data)
                fileHandle.closeFile()
            }
        }
    }
}

@MainActor package final class Zenz {
    package var resourceURL: URL
    package let ngl: Int
    private var zenzContext: ZenzContext?
    init(resourceURL: URL, ngl: Int = 0) throws {
        self.resourceURL = resourceURL
        self.ngl = ngl
        debugLog("[Zenz] init called with resourceURL: \(resourceURL), ngl: \(ngl)")
        do {
#if canImport(Darwin)
            if #available(iOS 16, macOS 13, *) {
                self.zenzContext = try ZenzContext.createContext(path: resourceURL.path(percentEncoded: false), ngl: ngl)
            } else {
                // this is not percent-encoded
                self.zenzContext = try ZenzContext.createContext(path: resourceURL.path, ngl: ngl)
            }
#else
            // this is not percent-encoded
            self.zenzContext = try ZenzContext.createContext(path: resourceURL.path, ngl: ngl)
#endif
            debugLog("[Zenz] Loaded model \(resourceURL.lastPathComponent) successfully with ngl=\(ngl)")
        } catch {
            throw error
        }
    }

    package func endSession() {
        try? self.zenzContext?.reset_context()
    }

    func candidateEvaluate(
        convertTarget: String,
        candidates: [Candidate],
        requestRichCandidates: Bool,
        personalizationMode: (mode: ConvertRequestOptions.ZenzaiMode.PersonalizationMode, base: EfficientNGram, personal: EfficientNGram)?,
        versionDependentConfig: ConvertRequestOptions.ZenzaiVersionDependentMode
    ) -> ZenzContext.CandidateEvaluationResult {
        guard let zenzContext else {
            return .error
        }
        for candidate in candidates {
            let result = zenzContext.evaluate_candidate(
                input: convertTarget.toKatakana(),
                candidate: candidate,
                requestRichCandidates: requestRichCandidates,
                personalizationMode: personalizationMode,
                versionDependentConfig: versionDependentConfig
            )
            return result
        }
        return .error
    }

    func predictNextCharacter(leftSideContext: String, count: Int) -> [(character: Character, value: Float)] {
        guard let zenzContext else {
            return []
        }
        let result = zenzContext.predict_next_character(leftSideContext: leftSideContext, count: count)
        return result
    }

    package func pureGreedyDecoding(pureInput: String, maxCount: Int = .max) -> String {
        return self.zenzContext?.pure_greedy_decoding(leftSideContext: pureInput, maxCount: maxCount) ?? ""
    }
}