import time
from typing import Union, Optional


class Post:
    def __init__(
        self,
        settings: dict,
        post_type: str,
        post_id: int,
        timestamp: int,
        path: str,
        title: str,
        text: str,
        username: str,
        cert_hash: str,
        parent: str,
        num_children: int,
        children: Optional[list] = None,
        current_page: Optional[int] = None,
    ) -> None:
    
        self.settings: dict = settings
        self.post_type: str = post_type
        self.post_id: int = post_id
        self.timestamp: int = timestamp
        self.path: str = path
        self.title: str = title
        self.text: str = text
        self.username: str = username
        self.cert_hash: str = cert_hash
        self.parent: str = parent
        self.num_children: int = num_children
        self.children: Optional[list] = children
        self.current_page: Optional[int] = current_page

        template_dir: str = self.settings["templateDir"]
        template_name: str = self.settings["postTypes"][self.post_type]["template"]
        mini_template_name: str = self.settings["postTypes"][self.post_type]["miniTemplate"]

        with open(
            "{}/{}.template".format(template_dir, template_name), "r"
        ) as template_file:
            self.template = template_file.read()

        if mini_template_name is not None:
            with open(
                "{}/{}.template".format(template_dir, mini_template_name), "r"
            ) as template_file:
                self.mini_template = template_file.read()

    def render_children(self) -> str:
        rendered_children: str = ""
        if self.children is None:
            return ""

        for child in self.children:
            rendered_children += child.render(mini=True)
        return rendered_children

    def render(self, mini: bool = False) -> str:

        hr_timestamp: str = time.strftime(
            "%a, %d %b %Y %H:%M:%S +0000",
            time.gmtime(int(self.timestamp) // 1000000000),
        )  # convert unix time in nanoseconds to human-readable utc time

        basename: str = self.path.split("/")[-1]
        cgi_safe_path: Union[list, str] = self.path.split("/")

        if len(cgi_safe_path) > 2:
            cgi_safe_path = cgi_safe_path[-2:]

        cgi_safe_path = "/".join(cgi_safe_path) 

        if self.username is None:
            self.username = "[no username]"
        if self.text is None:
            self.text = ""

        if mini:
            return self.mini_template.format(
                post_id=self.post_id,
                timestamp=hr_timestamp,
                path=cgi_safe_path,
                basename=basename,
                title=self.title,
                text=self.text,
                username=self.username,
                children=self.render_children(),
                num_children=self.num_children,
            )
        elif self.current_page is not None:
            next_page: int = self.current_page + 1
            previous_page: int = (self.current_page - 1) if self.current_page > 1 else 1
            return self.template.format(
                post_id=self.post_id,
                timestamp=hr_timestamp,
                path=cgi_safe_path,
                basename=basename,
                title=self.title,
                text=self.text,
                username=self.username,
                children=self.render_children(),
                num_children=self.num_children,
                current_page=self.current_page,
                previous_page=previous_page,
                next_page=next_page,
            )
        else:
            return self.template.format(
                post_id=self.post_id,
                timestamp=hr_timestamp,
                path=cgi_safe_path,
                basename=basename,
                title=self.title,
                username=self.username,
                text=self.text,
                children=self.render_children(),
                num_children=self.num_children,
                current_page=1,
                previous_page=1,
                next_page=1,
            )