#!/usr/bin/env python3

import sys
import json
import base64
import zlib

def pako_deflate(data):
    """Compress data using the same parameters as pako.deflate"""
    compress = zlib.compressobj(9, zlib.DEFLATED, 15, 8, zlib.Z_DEFAULT_STRATEGY)
    compressed_data = compress.compress(data)
    compressed_data += compress.flush()
    return compressed_data

def main():
    # Read all input from stdin
    mermaid_text = sys.stdin.read().strip()
    
    if not mermaid_text:
        print("Error: No mermaid text provided via stdin", file=sys.stderr)
        print("Usage: cat mermaid.md | python3 mermaid-to-url.py", file=sys.stderr)
        print("   or: echo 'graph TD; A-->B' | python3 mermaid-to-url.py", file=sys.stderr)
        sys.exit(1)
    
    # Create the mermaid object structure expected by mermaid.live
    mermaid_obj = {
        "code": mermaid_text,
        "mermaid": {
            "theme": "default"
        }
    }
    
    # Convert to JSON
    mermaid_json = json.dumps(mermaid_obj)
    
    # Compress using pako deflate parameters
    byte_data = mermaid_json.encode('ascii')
    compressed = pako_deflate(byte_data)
    
    # Base64 encode (URL-safe)
    encoded = base64.b64encode(compressed).decode('ascii')
    encoded = encoded.replace('+', '-').replace('/', '_')
    
    # Output the mermaid.live URL
    print(f"https://mermaid.live/edit#pako:{encoded}")

if __name__ == "__main__":
    main()