#!/bin/bash
# knowledge_digest.sh — knowledge-digester 子 Agent 的辅助脚本
# 被 knowledge-digester 子 Agent 调用，用于扫描 PDF 学习笔记并提取关键知识
#
# Usage:
#   ./knowledge_digest.sh scan          # 扫描所有 PDF 目录，输出统计
#   ./knowledge_digest.sh concept <kw>  # 搜索某个概念跨 PDF 的出现情况
#   ./knowledge_digest.sh recent <days> # 搜索最近修改的 PDF（按 atime）
#

INDEX_DIR="/root/personal/learn/pdf_index"
LEARN_DIR="/root/personal/learn"
DIGEST_DIR="/root/personal/notes/knowledge_digest"

mkdir -p "$DIGEST_DIR"

case "${1:-scan}" in
  scan)
    echo "=== Knowledge Digest: 目录统计 ==="
    echo "时间: $(date '+%Y-%m-%d %H:%M:%S')"
    echo ""
    for dir in "$LEARN_DIR"/lectures/BLDC_FOC/ \
               "$LEARN_DIR"/bldc_motor_control/pdfs/app_notes/ \
               "$LEARN_DIR"/humanoid_robot/ \
               "$LEARN_DIR"/oopc/; do
      if [ -d "$dir" ]; then
        count=$(find "$dir" -name "*.pdf" -type f | wc -l)
        echo "  $dir → $count PDF files"
      fi
    done
    echo ""
    echo "=== 索引 manifest ==="
    if [ -f "$INDEX_DIR/manifest.txt" ]; then
      wc -l < "$INDEX_DIR/manifest.txt"
      echo " entries in manifest"
    else
      echo "NO manifest found"
    fi
    ;;

  concept)
    keyword="${2:-FOC}"
    echo "=== Cross-PDF search: $keyword ==="
    echo "时间: $(date '+%Y-%m-%d %H:%M:%S')"
    echo ""
    for dir in "$LEARN_DIR"/lectures/BLDC_FOC/ \
               "$LEARN_DIR"/bldc_motor_control/pdfs/app_notes/ \
               "$LEARN_DIR"/humanoid_robot/; do
      [ -d "$dir" ] || continue
      find "$dir" -name "*.pdf" -type f 2>/dev/null | while read pdf; do
        match=$(pdftotext "$pdf" - 2>/dev/null | grep -ci "$keyword")
        if [ "$match" -gt 0 ]; then
          fname=$(basename "$pdf")
          echo "  [$match hits] $fname"
        fi
      done
    done
    ;;

  recent)
    days="${2:-7}"
    echo "=== PDF modified in last $days days ==="
    echo "时间: $(date '+%Y-%m-%d %H:%M:%S')"
    echo ""
    find "$LEARN_DIR" -name "*.pdf" -type f -mtime -"$days" 2>/dev/null | while read pdf; do
      fname=$(basename "$pdf")
      mtime=$(stat -c '%y' "$pdf" 2>/dev/null | cut -d. -f1)
      echo "  $mtime  $fname  ($(dirname "$pdf"))"
    done
    ;;

  *)
    echo "Usage: $0 {scan|concept <keyword>|recent <days>}"
    exit 1
    ;;
esac