#!/bin/bash

set -eu

# ensure 1 argument is passed
if [ "$#" -ne 1 ]; then
    echo "Usage: $0 <pr_number>"
    exit 1
fi

PR_NUMBER=$1
OLD=/tmp/orig_pr_body.txt
NEW=/tmp/new_pr_body.txt

gh pr view --json body --template "{{.body}}" "${PR_NUMBER}" > "${OLD}"
cp "${OLD}" "${NEW}"

# Remove markdown comments (like the <!-- markdownlint-disable --> at the start)
sed -i '/<!--.*-->$/d' "${NEW}"

# Remove "PLEASE FILL IN THE PR DESCRIPTION HERE ENSURING ALL CHECKLIST ITEMS (AT THE BOTTOM) HAVE BEEN CONSIDERED."
sed -i '/PLEASE FILL IN THE PR DESCRIPTION HERE.*$/d' "${NEW}"

# Remove all lines after and including "**BEFORE SUBMITTING, PLEASE READ THE CHECKLIST BELOW AND FILL IN THE DESCRIPTION ABOVE**"
sed -i '/\*\*BEFORE SUBMITTING, PLEASE READ.*\*\*/,$d' "${NEW}"

# Remove HTML <details> section that includes <summary> text of "PR Checklist (Click to Expand)"
python3 - <<EOF
import regex as re

with open("${NEW}", "r") as file:
    content = file.read()

pattern = re.compile(r'(---\n\n)?<details>.*?<summary>.*?PR Checklist \(Click to Expand\).*?</summary>.*?</details>', re.DOTALL)
content = re.sub(pattern, '', content)

with open("${NEW}", "w") as file:
    file.write(content)
EOF

# Run this only if ${NEW} is different than ${OLD}
if ! cmp -s "${OLD}" "${NEW}"; then
    gh pr edit --body-file "${NEW}" "${PR_NUMBER}"
    echo
    echo "Updated PR body:"
    echo
    cat "${NEW}"
else
    echo "No changes needed"
fi