feat: v0.1.12 — translate custom prompt + min 3min chapters + min 15s viral clips

Author: phuc-nt

package.json

@@ -1,7 +1,7 @@
 {
   "name": "my-media-kit",
   "private": true,
-  "version": "0.1.11",
+  "version": "0.1.12",
   "type": "module",
   "scripts": {
     "tauri": "tauri",

src-tauri/Cargo.toml

@@ -10,7 +10,7 @@ members = [
 ]
 
 [workspace.package]
-version = "0.1.11"
+version = "0.1.12"
 edition = "2021"
 authors = ["phucnt"]
 license = "MIT"

src-tauri/crates/content-kit/src/chapters.rs

@@ -31,8 +31,10 @@ pub fn system_prompt(language: &str, summary_hint: Option<&str>) -> String {
     format!(
         "You create YouTube chapter lists. Respond in {language}. First \
          chapter must start at 00:00. Keep titles short (under 8 words), \
-         meaningful, and descriptive of the upcoming section. Aim for 5-10 \
-         chapters for a 10-minute video; scale with length.{hint}"
+         meaningful, and descriptive of the upcoming section. \
+         MINIMUM chapter length: 3 minutes (180000 ms) — do NOT create \
+         chapters shorter than this. Merge short sections into broader \
+         topics instead of splitting aggressively.{hint}"
     )
 }
 
@@ -134,6 +136,18 @@ impl<'a> ChapterRunner for ProviderChapterRunner<'a> {
             first.timestamp_ms = 0;
         }
 
+        // Enforce minimum 3-minute gap between chapters. Drop any chapter
+        // that starts less than 180_000 ms after the previously kept one.
+        const MIN_GAP_MS: i64 = 180_000;
+        let mut filtered: Vec<Chapter> = Vec::with_capacity(chapters.len());
+        for c in chapters {
+            match filtered.last() {
+                Some(prev) if c.timestamp_ms - prev.timestamp_ms < MIN_GAP_MS => {}
+                _ => filtered.push(c),
+            }
+        }
+        chapters = filtered;
+
         Ok(ChapterList {
             language: language.into(),
             chapters,
@@ -181,16 +195,16 @@ mod tests {
             response: json!({
                 "chapters": [
                     { "timestampMs": 3_000, "title": "Intro" },
-                    { "timestampMs": 60_000, "title": "Main" }
+                    { "timestampMs": 240_000, "title": "Main" }
                 ]
             }),
         };
         let runner = ProviderChapterRunner { provider: &stub };
-        let segments = vec![TranscriptionSegment::new(0, 120_000, "full talk")];
-        let list = runner.run(&segments, "English", "claude-3").await.unwrap();
+        let segments = vec![TranscriptionSegment::new(0, 600_000, "full talk")];
+        let list = runner.run(&segments, "English", "claude-3", None).await.unwrap();
         assert_eq!(list.chapters.len(), 2);
         assert_eq!(list.chapters[0].timestamp_ms, 0);
-        assert_eq!(list.chapters[1].timestamp_ms, 60_000);
+        assert_eq!(list.chapters[1].timestamp_ms, 240_000);
     }
 
     #[tokio::test]
@@ -201,12 +215,12 @@ mod tests {
                 "chapters": [
                     { "timestampMs": 0, "title": "a" },
                     { "timestampMs": 0, "title": "a dup" },
-                    { "timestampMs": 5_000, "title": "b" }
+                    { "timestampMs": 200_000, "title": "b" }
                 ]
             }),
         };
         let runner = ProviderChapterRunner { provider: &stub };
-        let list = runner.run(&[], "English", "claude-3").await.unwrap();
+        let list = runner.run(&[], "English", "claude-3", None).await.unwrap();
         assert_eq!(list.chapters.len(), 2);
     }
 }

src-tauri/crates/content-kit/src/translate.rs

@@ -78,17 +78,25 @@ fn primary_tag(tag: &str) -> &str {
 
 /// `summary_hint` — brief content description injected into the system prompt so
 /// the model can maintain consistent terminology and proper-noun romanization.
-pub fn system_prompt(target_language_name: &str, summary_hint: Option<&str>) -> String {
+pub fn system_prompt(
+    target_language_name: &str,
+    summary_hint: Option<&str>,
+    custom_instruction: Option<&str>,
+) -> String {
     let hint_section = summary_hint
         .filter(|h| !h.trim().is_empty())
         .map(|h| format!(
             "\nContent context (use for consistent terminology and proper-noun \
              romanization across all batches): {h}"
         ))
         .unwrap_or_default();
+    let custom_section = custom_instruction
+        .filter(|h| !h.trim().is_empty())
+        .map(|h| format!("\nUser style/context instruction (follow this when translating): {h}"))
+        .unwrap_or_default();
     format!(
         "You are a professional subtitle translator. Your ONLY job is to translate \
-         text into {target_language_name}.{hint_section}\n\
+         text into {target_language_name}.{hint_section}{custom_section}\n\
          CRITICAL RULES:\n\
          - Every output string MUST be written entirely in {target_language_name}.\n\
          - Do NOT output Chinese characters, Japanese characters, or any other script.\n\
@@ -249,6 +257,7 @@ impl<'a> TranslateRunner for ProviderTranslateRunner<'a> {
                 batch,
                 target_name,
                 None,
+                None,
                 &prev_context,
             )
             .await?;
@@ -297,6 +306,7 @@ pub async fn translate_batch_with_retry(
     batch: &TranscriptBatch,
     target_name: &str,
     summary_hint: Option<&str>,
+    custom_instruction: Option<&str>,
     prev_context: &[String],
 ) -> Result<Vec<String>, AiProviderError> {
     let want = batch.segments.len();
@@ -331,7 +341,7 @@ pub async fn translate_batch_with_retry(
             max_tokens: 4096,
             ..CompletionRequest::structured(
                 model,
-                system_prompt(target_name, summary_hint),
+                system_prompt(target_name, summary_hint, custom_instruction),
                 user,
                 "TranslatedBatch",
                 response_schema(),
@@ -480,10 +490,12 @@ mod tests {
 
     #[test]
     fn system_prompt_includes_summary_hint() {
-        let p = system_prompt("Vietnamese", Some("A talk about rockets"));
+        let p = system_prompt("Vietnamese", Some("A talk about rockets"), None);
         assert!(p.contains("A talk about rockets"));
-        let p_no_hint = system_prompt("Vietnamese", None);
+        let p_no_hint = system_prompt("Vietnamese", None, None);
         assert!(!p_no_hint.contains("Content context"));
+        let p_custom = system_prompt("Vietnamese", None, Some("formal tone"));
+        assert!(p_custom.contains("formal tone"));
     }
 
     #[test]

src-tauri/crates/content-kit/src/viral_clips.rs

@@ -31,7 +31,10 @@ pub fn system_prompt(language: &str, summary_hint: Option<&str>) -> String {
     format!(
         "You are a social media content strategist. Analyze the transcript \
          and find 3-5 segments that would make the best short-form clips \
-         (15-60 seconds each) for YouTube Shorts, TikTok, or Reels.\n\n\
+         for YouTube Shorts, TikTok, or Reels. Each clip MUST be AT LEAST \
+         15 seconds long (endMs - startMs >= 15000) and at most 60 seconds. \
+         Extend the selection to include enough context if needed to reach \
+         the 15-second minimum.\n\n\
          For each clip provide:\n\
          - Precise start and end timestamps (in milliseconds)\n\
          - A hook explaining why this moment is engaging (emotional peak, \
@@ -133,14 +136,23 @@ impl<'a> ViralClipRunner for ProviderViralClipRunner<'a> {
         let parsed: ClipResponse =
             serde_json::from_value(value).map_err(|e| AiProviderError::Malformed(e.to_string()))?;
 
+        // Enforce 15s minimum — extend end_ms if the model returned a shorter clip.
+        const MIN_CLIP_MS: i64 = 15_000;
+        let transcript_end = segments.last().map(|s| s.end_ms).unwrap_or(i64::MAX);
         let mut clips: Vec<ViralClip> = parsed
             .clips
             .into_iter()
-            .map(|e| ViralClip {
-                start_ms: e.start_ms,
-                end_ms: e.end_ms,
-                hook: e.hook,
-                caption: e.caption,
+            .map(|e| {
+                let mut end_ms = e.end_ms;
+                if end_ms - e.start_ms < MIN_CLIP_MS {
+                    end_ms = (e.start_ms + MIN_CLIP_MS).min(transcript_end);
+                }
+                ViralClip {
+                    start_ms: e.start_ms,
+                    end_ms,
+                    hook: e.hook,
+                    caption: e.caption,
+                }
             })
             .collect();
 

src-tauri/src/commands/content.rs

@@ -92,6 +92,9 @@ pub struct TranslateCommandRequest {
     /// can maintain consistent terminology across batches.
     #[serde(default)]
     pub summary_hint: Option<String>,
+    /// Optional free-form user instruction to adjust style/context (tone, terminology, etc.).
+    #[serde(default)]
+    pub custom_instruction: Option<String>,
 }
 
 /// Tauri event emitted after each batch finishes. Payload: `{ batch, total, percent }`.
@@ -144,6 +147,7 @@ pub async fn content_translate(
             batch,
             target_name,
             request.summary_hint.as_deref(),
+            request.custom_instruction.as_deref(),
             &prev_context,
         )
         .await

src-tauri/tauri.conf.json

@@ -1,7 +1,7 @@
 {
   "$schema": "https://schema.tauri.app/config/2",
   "productName": "MyMediaKit",
-  "version": "0.1.11",
+  "version": "0.1.12",
   "identifier": "tech.lighton.media.MyMediaKit",
   "build": {
     "frontendDist": "../src"

src/index.html

@@ -89,6 +89,7 @@ <h3>Summary</h3>
           <h2>Translate</h2>
           <p class="hint">Translates to the output language set above. If already matching, originals returned unchanged.</p>
           <div class="actions">
+            <textarea id="translate-custom-prompt" rows="2" placeholder="Custom style or context (e.g. 'keep technical terms in English', 'formal tone', 'preserve humor and idioms')…" style="width:100%;resize:vertical;margin-bottom:6px;"></textarea>
             <button id="btn-translate" class="primary">Translate</button>
             <span id="translate-status" class="status">ready</span>
           </div>

src/js/features/translate.js

@@ -24,6 +24,8 @@ export function initTranslateView() {
   const btn = document.getElementById("btn-translate");
 
   // ── Progress bar (created inline, same pattern as YT download) ──────
+  const promptBox = document.getElementById("translate-custom-prompt");
+
   const progressBox = document.createElement("div");
   progressBox.className = "progress-box";
   progressBox.hidden = true;
@@ -83,6 +85,7 @@ export function initTranslateView() {
 
     try {
       const summary = getSummary();
+      const customInstruction = promptBox?.value.trim() || null;
       const out = await invoke("content_translate", {
         request: {
           provider,
@@ -91,6 +94,7 @@ export function initTranslateView() {
           sourceLanguage: source.transcript.language ?? null,
           targetLanguage: target,
           summaryHint: summary?.text ?? null,
+          customInstruction,
         },
       });
       lastResult = out;