#!/usr/bin/env bash
set -euo pipefail

# Deploy frontend to S3 and invalidate CloudFront cache.

usage() {
    cat <<'EOF'
Usage: ./deploy.sh --total-bundles N [OPTIONS]

Required:
  --total-bundles N       Number of bundle files (from bundle_gen output)

Optional:
  --site-bucket NAME      S3 bucket (default: everytab-site)
  --distribution-id ID    CloudFront distribution ID (default: auto-detect)
  --skip-invalidation     Don't invalidate CloudFront cache
  --help                  Show this help message

Example:
  ./deploy.sh --total-bundles 779
  ./deploy.sh --total-bundles 779 --distribution-id E14S2BLD6PG2XZ
EOF
    exit 0
}

TOTAL_BUNDLES=""
SITE_BUCKET="everytab-site"
DIST_ID=""
SKIP_INVALIDATION=false

if [ $# -eq 0 ]; then usage; fi

while [ $# -gt 0 ]; do
    case "$1" in
        --help) usage ;;
        --total-bundles) TOTAL_BUNDLES="$2"; shift 2 ;;
        --site-bucket) SITE_BUCKET="$2"; shift 2 ;;
        --distribution-id) DIST_ID="$2"; shift 2 ;;
        --skip-invalidation) SKIP_INVALIDATION=true; shift ;;
        *) echo "Unknown option: $1"; usage ;;
    esac
done

if [ -z "$TOTAL_BUNDLES" ]; then
    echo "ERROR: --total-bundles is required"
    exit 1
fi

# Find frontend directory (relative to this script)
SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
FRONTEND_DIR="$SCRIPT_DIR/../../frontend"

if [ ! -f "$FRONTEND_DIR/index.html" ]; then
    echo "ERROR: frontend/index.html not found at $FRONTEND_DIR"
    exit 1
fi

echo "=== Frontend Deploy ==="
echo "Total bundles: $TOTAL_BUNDLES"
echo "S3 bucket: $SITE_BUCKET"
echo ""

# Build into temp directory
TMPDIR=$(mktemp -d)
cp "$FRONTEND_DIR/index.html" "$TMPDIR/index.html"
cp "$FRONTEND_DIR/site.js" "$TMPDIR/site.js"
cp "$FRONTEND_DIR/bot.html" "$TMPDIR/bot.html"
cp "$FRONTEND_DIR/about.html" "$TMPDIR/about.html"

# Inject TOTAL_BUNDLES
sed -i "s/const TOTAL_BUNDLES = [0-9]*/const TOTAL_BUNDLES = ${TOTAL_BUNDLES}/" "$TMPDIR/index.html"
echo "Injected TOTAL_BUNDLES = $TOTAL_BUNDLES"

# Minify JS (strip comments + whitespace, keep variable names)
if command -v esbuild &>/dev/null; then
    esbuild "$TMPDIR/site.js" --minify --outfile="$TMPDIR/site.js" --allow-overwrite
    echo "Minified site.js"
else
    echo "Warning: esbuild not found, deploying unminified JS"
fi

# Upload
echo "Uploading to s3://$SITE_BUCKET/..."
aws s3 cp "$TMPDIR/index.html" "s3://$SITE_BUCKET/" --content-type "text/html"
aws s3 cp "$TMPDIR/site.js" "s3://$SITE_BUCKET/" --content-type "application/javascript"
aws s3 cp "$TMPDIR/bot.html" "s3://$SITE_BUCKET/" --content-type "text/html"
aws s3 cp "$TMPDIR/about.html" "s3://$SITE_BUCKET/" --content-type "text/html"
echo "Uploaded 4 files"

rm -rf "$TMPDIR"

# Clean up stale bundles from previous runs
echo "Cleaning stale bundles above $TOTAL_BUNDLES..."
STALE=$(aws s3api list-objects-v2 --bucket "$SITE_BUCKET" --prefix "tabs/" --query "Contents[].Key" --output text \
    | tr '\t' '\n' \
    | while read -r key; do
        num=$(echo "$key" | grep -oP '\d+' || true)
        if [ -n "$num" ] && [ "$((10#$num))" -ge "$TOTAL_BUNDLES" ]; then
            echo "$key"
        fi
    done)

if [ -n "$STALE" ]; then
    STALE_COUNT=$(echo "$STALE" | wc -l)
    echo "Deleting $STALE_COUNT stale bundles..."
    echo "$STALE" | while read -r key; do
        aws s3 rm "s3://$SITE_BUCKET/$key" --quiet
    done
    echo "Deleted $STALE_COUNT stale bundles"
else
    echo "No stale bundles found"
fi

# Invalidate CloudFront
if ! $SKIP_INVALIDATION; then
    if [ -z "$DIST_ID" ]; then
        DIST_ID=$(aws cloudfront list-distributions --query "DistributionList.Items[?Aliases.Items[?contains(@,'everytab')]].Id" --output text 2>/dev/null || true)
    fi

    if [ -n "$DIST_ID" ]; then
        echo "Invalidating CloudFront $DIST_ID..."
        aws cloudfront create-invalidation --distribution-id "$DIST_ID" --paths "/index.html" "/site.js" "/bot.html" "/about.html" > /dev/null
        echo "Invalidation submitted"
    else
        echo "Warning: no CloudFront distribution found, skipping invalidation"
    fi
fi

echo ""
echo "=== Deploy Complete ==="