import os
import mimetypes
from pathlib import Path
from email.message import EmailMessage
from email.headerregistry import Address

from jinja2 import Environment, FileSystemLoader

from ..config.email import EMAIL_CONFIG
from ..config.paths import HTML_PATHS


class EmailComposer:
    def __init__(self):
        self.sender = Address(
            display_name=EMAIL_CONFIG.sender_alias,
            addr_spec=EMAIL_CONFIG.sender_email,
        )
        self.reply_to = EMAIL_CONFIG.reply_to
    
    def compose(
        self,
        subject: str,
        recipients: list[str],
        body_html: str,
        image_attachments: list[tuple[Path, str]],
        mode: str = "prod",
    ) -> EmailMessage:
        email = EmailMessage()
        email["Subject"] = subject
        email["From"] = self.sender
        email["Reply-To"] = self.reply_to
        email["To"] = self.reply_to
        
        if mode == "dev":
            email["Cc"] = recipients
        else:
            email["Bcc"] = recipients
        
        email.set_content("This is a plain text body.")
        email.add_alternative(body_html, subtype="html")
        
        for path, cid in image_attachments:
            self._attach_image(email, path, cid)
        
        return email
    
    def build_body_html(
        self,
        section_htmls: str,
        legend_cid: str,
        report_date: str = "",
    ) -> str:
        env = Environment(
            loader=FileSystemLoader(str(HTML_PATHS.email.parent)),
            autoescape=False,
        )
        template = env.get_template(HTML_PATHS.email.name)
        return template.render(
            sections_html=section_htmls,
            legend_cid=f"cid:{legend_cid[1:-1]}",
            report_date=report_date,
        )
    
    def build_section_html(
        self,
        insights_link: str,
        spotify_link: str,
        image_cid: str,
        spotify_cid: str,
        img_height: float = 76.5,
        img_width: float = 765,
    ) -> str:
        return f'''
        <table class="table" align="center">
            <tr>
                <td>
                    <a href="{insights_link}"><img height="{img_height}" width="{img_width}"
                       src="cid:{image_cid[1:-1]}">
                    </a>
                </td>
                <td>
                    <a href="{spotify_link}"><img height="35" width="35"
                       src="cid:{spotify_cid[1:-1]}">
                    </a>
                </td>
            </tr>
        </table>
        '''
    
    @staticmethod
    def _attach_image(email: EmailMessage, path: Path, cid: str) -> None:
        with open(path, "rb") as img:
            mime_type = mimetypes.guess_type(str(path))[0] or "image/png"
            maintype, subtype = mime_type.split("/")
            email.get_payload()[1].add_related(
                img.read(),
                maintype=maintype,
                subtype=subtype,
                cid=cid,
            )