Persist selections and compile song output

2026-09-14 21:56:26 +02:00
parent 35703f89a8
commit 7bf4df79f9
10 changed files with 490 additions and 11 deletions
@@ -13,3 +13,83 @@ public struct CompiledSunoOutput: Equatable, Sendable {
        self.stylePrompt = stylePrompt
    }
 }
+
+public struct SongProjectPromptCompiler: PromptCompiling {
+    public init() {}
+
+    public func compile(project: SongProject) throws -> CompiledSunoOutput {
+        CompiledSunoOutput(
+            lyricsText: lyricsText(for: project),
+            stylePrompt: stylePrompt(for: project)
+        )
+    }
+
+    private func lyricsText(for project: SongProject) -> String {
+        if !project.lyrics.text.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty {
+            return project.lyrics.text
+        }
+
+        return project.orderedSections
+            .compactMap { section in
+                let lyrics = project.lyrics.sectionTexts[section.id] ?? section.lyrics
+                let trimmedLyrics = lyrics.trimmingCharacters(in: .whitespacesAndNewlines)
+                guard !trimmedLyrics.isEmpty else { return nil }
+                return "[\(section.title)]\n\(trimmedLyrics)"
+            }
+            .joined(separator: "\n\n")
+    }
+
+    private func stylePrompt(for project: SongProject) -> String {
+        let context = SongGenerationContext(project: project)
+        var components: [String] = []
+
+        append(project.genres.map(\.name).joined(separator: " + "), to: &components)
+        append(project.moods.map(\.name).joined(separator: ", "), to: &components)
+        append(context.sunoStyleInstrumentPhrase, to: &components)
+        append(vocalPhrase(for: project), to: &components)
+        append(musicalParametersPhrase(for: project), to: &components)
+        append(project.productionDirections.map(\.text).joined(separator: ", "), to: &components)
+
+        return components.joined(separator: "; ")
+    }
+
+    private func vocalPhrase(for project: SongProject) -> String {
+        project.vocalists
+            .map { vocalist in
+                [
+                    vocalist.label,
+                    vocalist.voiceType,
+                    vocalist.genderSelection,
+                    vocalist.performanceStyle
+                ]
+                    .compactMap { normalized($0) }
+                    .joined(separator: " ")
+            }
+            .filter { !$0.isEmpty }
+            .joined(separator: ", ")
+    }
+
+    private func musicalParametersPhrase(for project: SongProject) -> String {
+        var parameters: [String] = []
+
+        if let bpm = project.bpm?.value {
+            parameters.append("\(bpm) BPM")
+        }
+
+        append(project.key?.value.map { "key \($0)" }, to: &parameters)
+        append(project.scale?.value.map { "\($0) scale" }, to: &parameters)
+        append(project.maqam?.value.map { "maqam \($0)" }, to: &parameters)
+
+        return parameters.joined(separator: ", ")
+    }
+
+    private func append(_ value: String?, to components: inout [String]) {
+        guard let normalizedValue = normalized(value) else { return }
+        components.append(normalizedValue)
+    }
+
+    private func normalized(_ value: String?) -> String? {
+        let trimmedValue = value?.trimmingCharacters(in: .whitespacesAndNewlines)
+        return trimmedValue?.isEmpty == false ? trimmedValue : nil
+    }
+}