#!/usr/bin/env python3
"""CLI to chunk documents and print/save results."""

from __future__ import annotations

import argparse
import json
import sys
from pathlib import Path

sys.path.insert(0, str(Path(__file__).resolve().parent.parent / "backend"))

from rag_cut.models import SplitConfig, SplitMode
from rag_cut.pipeline import chunk_document


def main() -> None:
    parser = argparse.ArgumentParser(description="RAG-cut document chunking CLI")
    parser.add_argument("file", type=Path, help="Path to document")
    parser.add_argument(
        "--mode",
        choices=[m.value for m in SplitMode],
        default="default",
        help="Split mode",
    )
    parser.add_argument("--delimiter", default=None, help="Delimiter for delimiter mode")
    parser.add_argument("--parent-delimiter", default=None, help="Parent delimiter for parent_child mode")
    parser.add_argument("--child-delimiter", default=None, help="Child delimiter for parent_child mode")
    parser.add_argument("--max-chunk-size", type=int, default=1500, help="Parent/primary max chunk size")
    parser.add_argument("--child-max-size", type=int, default=512, help="Child max size for parent_child mode")
    parser.add_argument("--overlap", type=int, default=150)
    parser.add_argument("--header-row-start", type=int, default=1)
    parser.add_argument("--header-row-end", type=int, default=1)
    parser.add_argument("--start-row", type=int, default=2)
    parser.add_argument("--rows-per-chunk", type=int, default=1)
    parser.add_argument("-o", "--output", type=Path, default=None, help="Save JSON result")
    parser.add_argument("--preview", type=int, default=3, help="Print first N chunks")
    args = parser.parse_args()

    config = SplitConfig(
        mode=SplitMode(args.mode),
        delimiter=args.delimiter,
        parent_delimiter=args.parent_delimiter,
        child_delimiter=args.child_delimiter,
        max_chunk_size=args.max_chunk_size,
        child_max_size=args.child_max_size,
        overlap=args.overlap,
        header_row_start=args.header_row_start,
        header_row_end=args.header_row_end,
        start_row=args.start_row,
        rows_per_chunk=args.rows_per_chunk,
    )

    result = chunk_document(args.file, config=config)
    print(f"File: {result.filename}")
    print(f"Doc ID: {result.doc_id}")
    print(f"Blocks: {result.block_count} -> Chunks: {result.chunk_count}")
    print(f"Mode: {result.split_mode.value}")
    print("-" * 60)

    for chunk in result.chunks[: args.preview]:
        print(f"\n[Chunk {chunk.index}] ({chunk.char_count} chars) types={chunk.block_types}")
        preview = chunk.content[:500]
        print(preview + ("..." if len(chunk.content) > 500 else ""))

    if args.output:
        args.output.write_text(result.model_dump_json(indent=2), encoding="utf-8")
        print(f"\nSaved full result to {args.output}")


if __name__ == "__main__":
    main()