"""
Generate summaries from transcripts using Claude Code.
Reads manifest.json, processes each transcript, outputs per-lecture summaries,
and compiles SUPORT_CURS.md master study guide.

Usage:
  python summarize.py              # Print prompts for each transcript (pipe to Claude)
  python summarize.py --compile    # Compile existing summaries into SUPORT_CURS.md
"""

import json
import sys
import textwrap
from pathlib import Path

MANIFEST_PATH = Path("manifest.json")
SUMMARIES_DIR = Path("summaries")
TRANSCRIPTS_DIR = Path("transcripts")
MASTER_GUIDE = Path("SUPORT_CURS.md")

MAX_WORDS_PER_CHUNK = 10000
OVERLAP_WORDS = 500

SUMMARY_PROMPT = """Rezuma aceasta transcriere a unei lectii din cursul NLP Master Practitioner.

Ofera:
1. **Prezentare generala** - 3-5 propozitii care descriu subiectul principal al lectiei
2. **Concepte cheie** - lista cu definitii scurte pentru fiecare concept important
3. **Detalii si exemple importante** - informatii concrete, exercitii practice, exemple relevante mentionate de trainer
4. **Citate memorabile** - fraze sau idei remarcabile (daca exista)

Raspunde in limba romana. Formateaza ca Markdown.

---
TITLU LECTIE: {title}
---
TRANSCRIERE:
{text}
"""

MERGE_PROMPT = """Am mai multe rezumate partiale ale aceleiasi lectii (a fost prea lunga pentru un singur rezumat).
Combina-le intr-un singur rezumat coerent, eliminand duplicatele.

Pastreaza structura:
1. Prezentare generala (3-5 propozitii)
2. Concepte cheie cu definitii
3. Detalii si exemple importante
4. Citate memorabile

Raspunde in limba romana. Formateaza ca Markdown.

---
TITLU LECTIE: {title}
---
REZUMATE PARTIALE:
{chunks}
"""


def load_manifest() -> dict:
    with open(MANIFEST_PATH, encoding="utf-8") as f:
        return json.load(f)


def split_at_sentences(text: str, max_words: int, overlap: int) -> list[str]:
    """Split text into chunks at sentence boundaries with overlap."""
    words = text.split()
    if len(words) <= max_words:
        return [text]

    chunks = []
    start = 0
    while start < len(words):
        end = min(start + max_words, len(words))
        chunk_words = words[start:end]
        chunk_text = " ".join(chunk_words)

        # Try to break at sentence boundary (look back from end)
        if end < len(words):
            for sep in [". ", "! ", "? ", ".\n", "!\n", "?\n"]:
                last_sep = chunk_text.rfind(sep)
                if last_sep > len(chunk_text) // 2:  # Don't break too early
                    chunk_text = chunk_text[:last_sep + 1]
                    # Recalculate end based on actual words used
                    end = start + len(chunk_text.split())
                    break

        chunks.append(chunk_text)
        start = max(end - overlap, start + 1)  # Overlap, but always advance

    return chunks


def generate_prompts(manifest: dict):
    """Print summary prompts for each transcript to stdout."""
    SUMMARIES_DIR.mkdir(exist_ok=True)

    for mod in manifest["modules"]:
        for lec in mod["lectures"]:
            if lec.get("transcribe_status") != "complete":
                continue

            summary_path = Path(lec["summary_path"])
            if summary_path.exists() and summary_path.stat().st_size > 0:
                print(f"# SKIP (exists): {lec['title']}", file=sys.stderr)
                continue

            txt_path = Path(lec["transcript_path"])
            if not txt_path.exists():
                print(f"# SKIP (no transcript): {lec['title']}", file=sys.stderr)
                continue

            text = txt_path.read_text(encoding="utf-8").strip()
            if not text:
                print(f"# SKIP (empty): {lec['title']}", file=sys.stderr)
                continue

            chunks = split_at_sentences(text, MAX_WORDS_PER_CHUNK, OVERLAP_WORDS)

            print(f"\n{'='*60}", file=sys.stderr)
            print(f"Lecture: {lec['title']}", file=sys.stderr)
            print(f"Words: {len(text.split())}, Chunks: {len(chunks)}", file=sys.stderr)
            print(f"Output: {summary_path}", file=sys.stderr)

            if len(chunks) == 1:
                prompt = SUMMARY_PROMPT.format(title=lec["title"], text=text)
                print(f"SUMMARY_FILE:{summary_path}")
                print(prompt)
                print("---END_PROMPT---")
            else:
                # Multi-chunk: generate individual chunk prompts
                for i, chunk in enumerate(chunks, 1):
                    prompt = SUMMARY_PROMPT.format(
                        title=f"{lec['title']} (partea {i}/{len(chunks)})",
                        text=chunk,
                    )
                    print(f"CHUNK_PROMPT:{i}/{len(chunks)}:{summary_path}")
                    print(prompt)
                    print("---END_PROMPT---")

                # Then a merge prompt
                print(f"MERGE_FILE:{summary_path}")
                merge = MERGE_PROMPT.format(
                    title=lec["title"],
                    chunks="{chunk_summaries}",  # Placeholder for merge step
                )
                print(merge)
                print("---END_PROMPT---")


def compile_master_guide(manifest: dict):
    """Compile all summaries into SUPORT_CURS.md."""
    lines = [
        "# SUPORT CURS - NLP Master Practitioner Bucuresti 2025\n",
        "_Generat automat din transcrierile audio ale cursului._\n",
        "---\n",
    ]

    for mod in manifest["modules"]:
        lines.append(f"\n## {mod['name']}\n")

        for lec in mod["lectures"]:
            summary_path = Path(lec["summary_path"])
            lines.append(f"\n### {lec['title']}\n")

            if summary_path.exists():
                content = summary_path.read_text(encoding="utf-8").strip()
                lines.append(f"{content}\n")
            else:
                lines.append("_Rezumat indisponibil._\n")

        lines.append("\n---\n")

    MASTER_GUIDE.write_text("\n".join(lines), encoding="utf-8")
    print(f"Compiled {MASTER_GUIDE} ({MASTER_GUIDE.stat().st_size} bytes)")


def main():
    if not MANIFEST_PATH.exists():
        print("manifest.json not found. Run download.py and transcribe.py first.")
        sys.exit(1)

    manifest = load_manifest()

    if "--compile" in sys.argv:
        compile_master_guide(manifest)
    else:
        generate_prompts(manifest)


if __name__ == "__main__":
    main()