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

GHCR_PAT="$1"
NEW_TAG="${2:-latest}"
TAG_FILE="/var/lib/polyweather/.current_tag"
COMPOSE_DIR="/root/PolyWeather"

echo "$GHCR_PAT" | docker login ghcr.io -u yangyuan-zhen --password-stdin

cd "$COMPOSE_DIR"
git fetch origin main && git reset --hard origin/main

PREVIOUS_TAG=""
if [ -f "$TAG_FILE" ]; then
    PREVIOUS_TAG=$(cat "$TAG_FILE")
    echo "Previous tag: $PREVIOUS_TAG"
fi

export IMAGE_TAG="$NEW_TAG"
pull_ok=0
for pull_attempt in $(seq 1 6); do
    docker compose pull && pull_ok=1 && break
    echo "Image pull failed or tag not ready, retry ${pull_attempt}/6..."
    sleep 10
done
if [ "$pull_ok" != "1" ]; then
    echo "❌ Image pull failed after retries"
    exit 1
fi
docker compose up -d

smoke_check() {
    local name="$1"
    local url="$2"
    local timeout="$3"
    local attempts="${4:-6}"
    local delay="${5:-5}"

    for i in $(seq 1 "$attempts"); do
        if curl -fsSo /dev/null --max-time "$timeout" "$url"; then
            echo "✅ $name"
            return 0
        fi
        if [ "$i" != "$attempts" ]; then
            echo "   $name retry $i/$attempts..."
            sleep "$delay"
        fi
    done

    echo "❌ $name"
    return 1
}

# Wait for backend to be ready (retry up to 150s)
echo "Waiting for backend..."
for i in $(seq 1 30); do
    sleep 5
    if curl -fsSo /dev/null --max-time 5 "https://api.polyweather.top/healthz"; then
        echo "✅ healthz ready after ${i}x5s"
        break
    fi
    echo "   retry $i/30..."
done

FAILED=0
smoke_check "healthz" "https://api.polyweather.top/healthz" 15 3 5 || FAILED=1
smoke_check "cities" "https://api.polyweather.top/api/cities" 15 8 5 || FAILED=1
smoke_check "frontend" "https://www.polyweather.top/" 15 3 5 || FAILED=1

if [ "$FAILED" = "1" ]; then
    echo "❌ Smoke tests failed. Rolling back..."
    if [ -n "$PREVIOUS_TAG" ]; then
        export IMAGE_TAG="$PREVIOUS_TAG"
        docker compose pull
        docker compose up -d
        echo "✅ Rolled back to $PREVIOUS_TAG"
    else
        echo "⚠️  No previous tag to rollback to"
    fi
    exit 1
fi

mkdir -p "$(dirname "$TAG_FILE")"
echo "$NEW_TAG" > "$TAG_FILE"
docker image prune -af
echo "✅ Deployed $NEW_TAG"