#!/usr/bin/env python3 """Render a trucking campaign body with coupon merge-tags filled in and score it through local SpamAssassin (4.0.1). Reads the body HTML from a file. Usage: sa_coupon_local.py

"""
import html
import re
import subprocess
import sys
from email.message import EmailMessage
from email.utils import formatdate, make_msgid

BODY_FILE = sys.argv[1]
SUBJECT_TPL = sys.argv[2]
PCT = sys.argv[3] if len(sys.argv) > 3 else "40"
CODE = sys.argv[4] if len(sys.argv) > 4 else "KQMTN"

body = open(BODY_FILE, encoding="utf-8").read()

attribs = {
    "dot_number": "1228791",
    "company": "BLUE RIDGE FREIGHT LLC",
    "state": "CT",
    "lp_link": f"https://performancewest.net/order/mcs150-update?code={CODE}",
    "coupon_code": CODE,
    "coupon_pct": PCT,
    "coupon_expires": "11:59 PM ET tonight",
}


def render(tpl: str, at: dict) -> str:
    pat = re.compile(
        r"\{\{\s*if\s+\.Subscriber\.Attribs\.(\w+)\s*\}\}(.*?)"
        r"(?:\{\{\s*else\s*\}\}(.*?))?\{\{\s*end\s*\}\}",
        re.DOTALL,
    )

    def repl(m):
        key, t_branch, f_branch = m.group(1), m.group(2), m.group(3) or ""
        return t_branch if str(at.get(key, "")).strip() else f_branch

    prev = None
    while prev != tpl:
        prev = tpl
        tpl = pat.sub(repl, tpl)

    def val(m):
        return html.escape(str(at.get(m.group(1), "")))

    tpl = re.sub(r"\{\{\s*\.Subscriber\.Attribs\.(\w+)\s*\}\}", val, tpl)
    tpl = tpl.replace("{{ UnsubscribeURL }}", "https://performancewest.net/unsubscribe/abc123")
    tpl = re.sub(r"\{\{[^}]*\}\}", "", tpl)
    return tpl


rendered_subject = render(SUBJECT_TPL, attribs)
rendered_body = render(body, attribs)

msg = EmailMessage()
msg["From"] = "Performance West "
msg["To"] = "dispatch@blueridgefreight.com"
msg["Subject"] = rendered_subject
msg["Date"] = formatdate(localtime=True)
msg["Message-ID"] = make_msgid(domain="performancewest.net")
msg["List-Unsubscribe"] = ", "
msg["List-Unsubscribe-Post"] = "List-Unsubscribe=One-Click"
msg["Precedence"] = "bulk"

text_alt = re.sub(r"<[^>]+>", "", rendered_body)
text_alt = html.unescape(re.sub(r"\n{3,}", "\n\n", text_alt)).strip()
msg.set_content(text_alt)
msg.add_alternative(rendered_body, subtype="html")

raw = msg.as_bytes()

proc = subprocess.run(["spamassassin", "-t", "-L"], input=raw, capture_output=True)
scored = proc.stdout.decode("utf-8", "replace")

score_line = ""
for line in scored.splitlines():
    if line.startswith("X-Spam-Status:"):
        score_line = line
        break

m = re.search(r"score=([-0-9.]+)", score_line)
score = m.group(1) if m else "?"
verdict = "SPAM" if score_line.startswith("X-Spam-Status: Yes") else "HAM"

print(f"arm={PCT}% code={CODE}  ->  SCORE {score}  [{verdict}]   subj: {rendered_subject}")

# Detailed rule report.
rep = re.search(r"X-Spam-Report:(.*?)\n(?:[A-Za-z-]+:|\n)", scored, re.DOTALL)
if "--verbose" in sys.argv:
    if rep:
        print(rep.group(1))
    else:
        for line in scored.splitlines():
            if re.match(r"^\s*[-0-9.]+\s+[A-Z0-9_]+", line):
                print("   ", line.strip())