#!/usr/bin/env bash
# Sandcastle → Kubernetes hand-off script.
#
# Reads the greeting `value` from the Sandcastle-produced branch (default
# `sandcastle/hello-world-pico` on the durable target repo the Sandcastle
# lab created under work/hello-world-pico-sandcastle/target-repo) and
# writes a Crossplane XHelloWorldPico Composite Resource carrying the
# same value. The generated XR is the exact shape consumed by the
# existing labs/hello-pico-on-kubernetes lab (see its 05-xr.yaml).
#
# Usage: handoff.sh [<work-root>]
#   work-root defaults to work/handoff-sandcastle-to-kubernetes
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
REPO_ROOT="$(cd "$SCRIPT_DIR/../../.." && pwd)"

SANDCASTLE_WORK="${SANDCASTLE_WORK:-$REPO_ROOT/work/hello-world-pico-sandcastle}"
TARGET_REPO="${TARGET_REPO:-$SANDCASTLE_WORK/target-repo}"
BRANCH="${BRANCH:-sandcastle/hello-world-pico}"
RULE_PATH="${RULE_PATH:-rules/hello.yaml}"
XR_NAME="${XR_NAME:-hello}"

WORK_ROOT="${1:-$REPO_ROOT/work/handoff-sandcastle-to-kubernetes}"
BUILD_DIR="$WORK_ROOT/build"
XR_OUT="$BUILD_DIR/xr.yaml"

if [ ! -d "$TARGET_REPO" ]; then
  printf 'handoff: sandcastle target repo not found at %s\n' "$TARGET_REPO" >&2
  printf 'handoff: run labs/hello-world-pico-sandcastle/downloads/sandcastle-run.sh first\n' >&2
  exit 2
fi
if ! git -C "$TARGET_REPO" rev-parse "$BRANCH" >/dev/null 2>&1; then
  printf 'handoff: branch %s not found in %s\n' "$BRANCH" "$TARGET_REPO" >&2
  exit 2
fi

RULE_YAML="$(git -C "$TARGET_REPO" show "${BRANCH}:${RULE_PATH}")"

VALUE="$(RULE_YAML="$RULE_YAML" python3 <<'PY'
import os, re, sys
text = os.environ.get("RULE_YAML", "")
val = None
for line in text.splitlines():
    m = re.match(r"^\s*value\s*:\s*(.+?)\s*$", line)
    if m:
        v = m.group(1)
        if len(v) >= 2 and v[0] == v[-1] and v[0] in ("'", '"'):
            v = v[1:-1]
        val = v
        break
if val is None:
    sys.stderr.write("handoff: could not find `value:` field in rule\n")
    sys.exit(3)
print(val)
PY
)"

if [ -z "$VALUE" ]; then
  printf 'handoff: empty value extracted from %s on %s\n' "$RULE_PATH" "$BRANCH" >&2
  exit 3
fi

mkdir -p "$BUILD_DIR"

# Emit the XR YAML. Shape matches labs/hello-pico-on-kubernetes/downloads/05-xr.yaml.
cat > "$XR_OUT" <<EOF
# Generated by labs/handoff-sandcastle-to-kubernetes/downloads/handoff.sh
# Source: branch=${BRANCH} file=${RULE_PATH} value=$(printf '%q' "$VALUE")
apiVersion: oe.academy/v1alpha1
kind: XHelloWorldPico
metadata:
  name: ${XR_NAME}
spec:
  value: "${VALUE}"
EOF

printf 'handoff: wrote %s (value=%q)\n' "$XR_OUT" "$VALUE"
printf 'handoff: apply with `kubectl apply -f %s` after completing labs/hello-pico-on-kubernetes/ steps 1-4\n' "$XR_OUT"