#!/bin/bash
# ============================================================================
# Name        : fetch_release.sh
# Description : Fetches a GitHub release, downloads all assets (including
#               source code), and generates a Debian-style changelog README.
# ============================================================================

# Configuration variables
REPO="termux/proot-distro"
TAG="v4.29.0"
PKG_NAME="proot-distro"
DIR_NAME="${PKG_NAME}-${TAG}"
API_URL="https://api.github.com/repos/${REPO}/releases/tags/${TAG}"

# Ensure required tools are installed
if ! command -v curl &> /dev/null || ! command -v jq &> /dev/null; then
    echo "Error: 'curl' and 'jq' are required. Please install them."
    exit 1
fi

echo "Fetching release data for ${REPO} at tag ${TAG}..."
RELEASE_JSON=$(curl -s "$API_URL")

# Validate if the release exists
if echo "$RELEASE_JSON" | grep -q '"message": "Not Found"'; then
    echo "Error: Release not found!"
    exit 1
fi

# Extract metadata using jq
VERSION=$(echo "$RELEASE_JSON" | jq -r '.tag_name')
AUTHOR=$(echo "$RELEASE_JSON" | jq -r '.author.login')
DATE_RAW=$(echo "$RELEASE_JSON" | jq -r '.published_at')
BODY=$(echo "$RELEASE_JSON" | jq -r '.body')
TARBALL_URL=$(echo "$RELEASE_JSON" | jq -r '.tarball_url')
ZIPBALL_URL=$(echo "$RELEASE_JSON" | jq -r '.zipball_url')

# Format date to RFC 2822 (Standard Debian changelog style) if possible
# Fallback to the raw ISO 8601 date if 'date -d' is not supported (e.g., macOS/BSD)
DATE_FORMATTED=$(date -d "$DATE_RAW" -R 2>/dev/null || echo "$DATE_RAW")

# Create and enter the release directory
echo "Creating directory: ${DIR_NAME}..."
mkdir -p "$DIR_NAME"
cd "$DIR_NAME" || exit 1

# Generate the Debian-style README.txt
echo "Generating README.txt..."
cat <<EOF > README.txt
${PKG_NAME} - ${VERSION}

${BODY}

 -- ${AUTHOR} - ${DATE_FORMATTED}
EOF

# Download all compiled assets attached to the release
echo "Downloading release assets..."
echo "$RELEASE_JSON" | jq -r '.assets[] | "\(.browser_download_url) \(.name)"' | while read -r url name; do
    if [ -n "$url" ] && [ "$url" != "null" ]; then
        echo " -> Downloading ${name}..."
        curl -L -# -o "$name" "$url"
    fi
done

# Download source code archives
echo "Downloading source code (tar.gz)..."
curl -L -# -o "${PKG_NAME}-${VERSION}-source.tar.gz" "$TARBALL_URL"

echo "Downloading source code (zip)..."
curl -L -# -o "${PKG_NAME}-${VERSION}-source.zip" "$ZIPBALL_URL"

echo "========================================"
echo "Done! All files saved in: ./${DIR_NAME}/"
ls -lh