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

class NFDocs(Directive):
    # Class default overrides
    required_arguments = 1

    # 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 += self.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

    def run(self):
        # Take path as single argument for now
        nextflow_path = self.arguments[0]
        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(self.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(self.DOC_STARTER):
                        doc_start = i
                    if not line_next.startswith(self.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 = self.definition_type(nextflow_lines[pos[-1]+1])
                doc_yaml = ""
                for i in pos:
                    doc_yaml = doc_yaml + nextflow_lines[i].replace(self.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 += self.params_to_list(io)
                            io_section += io_list
                            proc_section += io_section
                    block_section += proc_section

                return_nodes.append(block_section)

            return return_nodes