#!/usr/bin/env python
import sys
import yaml
from docutils import nodes
from docutils.parsers.rst import Directive

class NFDocs(Directive):

    # Declare the docstring starting characters
    DOC_STARTER = "/// "

    def definition_type(signature):
        # Returns "name", workflow|process|function
        def_type = "unknown"
        if "workflow" in signature:
            def_type = "workflow"
        elif "process" in signature:
            def_type = "process"
        elif "function" in signature:
            def_type = "function"

        # Check if any signature was recognized
        if def_type == "unknown":
            return "unknown", "an error occurred"

        # Parse out the definition name
        def_name = signature.replace(def_type, "").replace("{", "").strip()

        # Return the results
        return def_name, def_type

    def params_to_list(params):
        if "tuple" in params.keys():
            tuple_item = nodes.list_item()
            if "name" in params.keys():
                tuple_item += nodes.paragraph(text=params["name"])
            tuple_item += nodes.paragraph(text="Tuple:")
            tuple_list = nodes.bullet_list()
            for io in params["tuple"]:
                tuple_list += params_to_list(io)
            tuple_item += tuple_list
            return tuple_item
        else:
            io_item = nodes.list_item()
            if "name" in params.keys():
                io_item += nodes.paragraph(text=params["name"])
            io_item += nodes.paragraph(text=f"Type: {params['type']}")
            io_item += nodes.paragraph(text=params["description"])
            return io_item

    # Take path as single argument for now
    nextflow_path = sys.argv[1]
    with open(nextflow_path) as nextflow_file:

        # Split by lines
        nextflow_lines = nextflow_file.readlines()

        # Declare some variables to keep track of where the docstrings begin and end
        doc_start = 0
        doc_end = 0

        # Declare dictionaries to keep track of the docstrings
        docstring_positions = []

        # Calculate the start and end positions of each docstring
        for i, line in enumerate(nextflow_lines):
            # Check if this is a docstring
            if line.startswith(DOC_STARTER):
                # It is: check the next and previous lines to see if this is part of a block
                line_previous = nextflow_lines[i-1]
                line_next = nextflow_lines[i+1]
                if not line_previous.startswith(DOC_STARTER):
                    doc_start = i
                if not line_next.startswith(DOC_STARTER):
                    doc_end = i

                # Check if we've reached the end of a docstring block
                if doc_end == i:
                    # Add this docstring position to the array
                    docstring_positions.append(range(doc_start, doc_end+1))

        # Create dictionaries for each of the block types
        docstrings = {
            "process": {},
            "workflow": {},
            "function": {}
        }

        # Parse out the docstrings and put them in the appropriate dictionary
        for pos in docstring_positions:
            proc_name, proc_type = definition_type(nextflow_lines[pos[-1]+1])
            doc_yaml = ""
            for i in pos:
                doc_yaml = doc_yaml + nextflow_lines[i].replace(DOC_STARTER, "")
            docstrings[proc_type][proc_name] = yaml.safe_load(doc_yaml)

        # Create any array to return from the plugin
        return_nodes = []

        # Try to convert each definition to a node
        for block_type, block_docs in docstrings.items():
            block_section = nodes.section()
            block_section += nodes.title(text=block_type)
            for proc_name, proc_docs in block_docs.items():
                proc_section = nodes.section()
                proc_section += nodes.title(text=proc_name)
                proc_section += nodes.paragraph(text=proc_docs["summary"])
                io_methods = ["input", "output"]
                for met in io_methods:
                    if met in proc_docs.keys():
                        io_section = nodes.section()
                        io_section += nodes.title(text=met)
                        io_list = nodes.bullet_list()
                        for io in proc_docs[met]:
                            io_list += params_to_list(io)
                        io_section += io_list
                        proc_section += io_section
                block_section += proc_section

            return_nodes.append(block_section)

        print(return_nodes)