feat: add local voice transcription pipeline

src/summary.rs

@@ -0,0 +1,193 @@
+use std::collections::HashSet;
+
+use reqwest::header::{AUTHORIZATION, CONTENT_TYPE};
+use serde::{Deserialize, Serialize};
+
+use crate::config::SummaryConfig;
+
+const MAX_FEEDBACK_CHARS: usize = 2000;
+
+#[derive(Clone)]
+pub struct SummaryService {
+    config: Option<SummaryConfig>,
+    client: reqwest::Client,
+}
+
+#[derive(Debug)]
+pub struct SummaryResult {
+    pub content: String,
+    pub method: &'static str,
+}
+
+#[derive(Serialize)]
+struct ChatRequest<'a> {
+    model: &'a str,
+    messages: Vec<ChatMessage<'a>>,
+    temperature: f32,
+}
+
+#[derive(Serialize)]
+struct ChatMessage<'a> {
+    role: &'a str,
+    content: &'a str,
+}
+
+#[derive(Deserialize)]
+struct ChatResponse {
+    choices: Vec<ChatChoice>,
+}
+
+#[derive(Deserialize)]
+struct ChatChoice {
+    message: ChatChoiceMessage,
+}
+
+#[derive(Deserialize)]
+struct ChatChoiceMessage {
+    content: String,
+}
+
+impl SummaryService {
+    pub fn new(config: Option<SummaryConfig>) -> Self {
+        Self {
+            config,
+            client: reqwest::Client::new(),
+        }
+    }
+
+    pub fn configured(&self) -> bool {
+        self.config.is_some()
+    }
+
+    pub async fn summarize(
+        &self,
+        existing_content: &str,
+        lesson_transcripts: &[String],
+    ) -> Result<SummaryResult, String> {
+        let Some(config) = &self.config else {
+            return Ok(SummaryResult {
+                content: extractive_summary(existing_content, lesson_transcripts),
+                method: "extractive",
+            });
+        };
+
+        let transcript_text = lesson_transcripts
+            .iter()
+            .enumerate()
+            .map(|(index, transcript)| format!("第{}节课：\n{}", index + 1, transcript))
+            .collect::<Vec<_>>()
+            .join("\n\n");
+        let user_prompt = format!(
+            "教师已填写内容：\n{}\n\n新增课堂转录：\n{}",
+            existing_content.trim(),
+            transcript_text
+        );
+        let system_prompt = "你是教学反馈整理助手。请把教师已有内容与课堂转录合并成一份面向家长的中文反馈，保留具体事实，按课堂表现、进步、问题和后续建议组织。不要虚构，不要提及录音或转录，不超过2000个汉字，只输出反馈正文。";
+        let request = ChatRequest {
+            model: &config.model,
+            messages: vec![
+                ChatMessage {
+                    role: "system",
+                    content: system_prompt,
+                },
+                ChatMessage {
+                    role: "user",
+                    content: &user_prompt,
+                },
+            ],
+            temperature: 0.2,
+        };
+        let mut builder = self
+            .client
+            .post(&config.api_url)
+            .header(CONTENT_TYPE, "application/json")
+            .json(&request);
+        if let Some(api_key) = &config.api_key {
+            builder = builder.header(AUTHORIZATION, format!("Bearer {api_key}"));
+        }
+        let response = builder
+            .send()
+            .await
+            .map_err(|error| format!("反馈汇总服务连接失败：{error}"))?;
+        let status = response.status();
+        if !status.is_success() {
+            return Err(format!("反馈汇总服务返回 HTTP {status}"));
+        }
+        let result: ChatResponse = response
+            .json()
+            .await
+            .map_err(|error| format!("反馈汇总响应格式无效：{error}"))?;
+        let content = result
+            .choices
+            .into_iter()
+            .next()
+            .map(|choice| choice.message.content.trim().to_owned())
+            .filter(|content| !content.is_empty())
+            .ok_or_else(|| "反馈汇总服务未返回内容".to_owned())?;
+
+        Ok(SummaryResult {
+            content: content.chars().take(MAX_FEEDBACK_CHARS).collect(),
+            method: "llm",
+        })
+    }
+}
+
+fn extractive_summary(existing_content: &str, lesson_transcripts: &[String]) -> String {
+    let existing = existing_content.trim();
+    let mut result = existing
+        .chars()
+        .take(MAX_FEEDBACK_CHARS)
+        .collect::<String>();
+    let mut seen = HashSet::new();
+    let mut selected = Vec::new();
+
+    for transcript in lesson_transcripts {
+        for sentence in transcript.split_inclusive(['。', '！', '？', '\n']) {
+            let sentence = sentence.trim();
+            if sentence.chars().count() < 4 || !seen.insert(sentence.to_owned()) {
+                continue;
+            }
+            selected.push(sentence.to_owned());
+        }
+    }
+
+    if !selected.is_empty() && result.chars().count() < MAX_FEEDBACK_CHARS {
+        if !result.is_empty() {
+            result.push_str("\n\n");
+        }
+        result.push_str("课堂记录汇总：\n");
+        for sentence in selected {
+            let prefix = "- ";
+            let remaining = MAX_FEEDBACK_CHARS.saturating_sub(result.chars().count());
+            if remaining <= prefix.chars().count() + 4 {
+                break;
+            }
+            result.push_str(prefix);
+            result.extend(
+                sentence
+                    .chars()
+                    .take(remaining - prefix.chars().count() - 1),
+            );
+            result.push('\n');
+        }
+    }
+
+    result.trim().to_owned()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::extractive_summary;
+
+    #[test]
+    fn extractive_summary_preserves_manual_content_and_deduplicates() {
+        let result = extractive_summary(
+            "手动备注。",
+            &["完成了构图练习。完成了构图练习。色彩更大胆。".to_owned()],
+        );
+
+        assert!(result.starts_with("手动备注。"));
+        assert_eq!(result.matches("完成了构图练习。").count(), 1);
+        assert!(result.contains("色彩更大胆。"));
+    }
+}