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

# =============================================================================
# phase9_security.sh — Deploy security scanning workflows to all repos
# Depends on: Phase 5 complete (repos have .gitea/workflows/)
# For each repo:
#   1. Clone from Gitea to temp directory
#   2. Render security-scan.yml.tpl → .gitea/workflows/security-scan.yml
#   3. Commit and push
#   4. If SECURITY_FAIL_ON_ERROR=true, update branch protection to require
#      security status checks (semgrep, trivy, gitleaks)
# The security workflow runs Semgrep (SAST), Trivy (container/dependency scan),
# and Gitleaks (secret detection) on every pull request.
# Idempotent: skips repos that already have security-scan.yml.
# =============================================================================

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
source "${SCRIPT_DIR}/lib/common.sh"

load_env
require_vars GITEA_ADMIN_TOKEN GITEA_INTERNAL_URL GITEA_ORG_NAME \
             GITEA_ADMIN_USER \
             REPO_1_NAME REPO_2_NAME REPO_3_NAME \
             SEMGREP_VERSION TRIVY_VERSION GITLEAKS_VERSION \
             SECURITY_FAIL_ON_ERROR PROTECTED_BRANCH

phase_header 9 "Security Scanning"

REPOS=("$REPO_1_NAME" "$REPO_2_NAME" "$REPO_3_NAME")
TEMP_BASE="/tmp/gitea-migration-security"
GITEA_BASE_URL="${GITEA_INTERNAL_URL%/}"
ASKPASS_SCRIPT=""

# Clean up cloned repos and ephemeral auth script on exit (even on failure).
cleanup() {
  rm -rf "$TEMP_BASE"
  if [[ -n "$ASKPASS_SCRIPT" ]]; then
    rm -f "$ASKPASS_SCRIPT"
  fi
}
trap cleanup EXIT

# Create an ephemeral GIT_ASKPASS script so tokens are never embedded in
# git remote URLs. Git calls this script with "Username for ..." or
# "Password for ..." and the script responds from environment variables.
setup_git_auth() {
  ASKPASS_SCRIPT=$(mktemp)
  cat > "$ASKPASS_SCRIPT" <<'EOF'
#!/usr/bin/env sh
case "$1" in
  *sername*) printf '%s\n' "$GITEA_GIT_USERNAME" ;;
  *assword*) printf '%s\n' "$GITEA_GIT_TOKEN" ;;
  *) printf '\n' ;;
esac
EOF
  chmod 700 "$ASKPASS_SCRIPT"
}

git_with_auth() {
  GIT_TERMINAL_PROMPT=0 \
  GIT_ASKPASS="$ASKPASS_SCRIPT" \
  GITEA_GIT_USERNAME="$GITEA_ADMIN_USER" \
  GITEA_GIT_TOKEN="$GITEA_ADMIN_TOKEN" \
  "$@"
}

SUCCESS=0
SKIPPED=0
FAILED=0

setup_git_auth

for repo in "${REPOS[@]}"; do
  log_info "--- Processing repo: ${repo} ---"

  # -------------------------------------------------------------------------
  # Idempotency: check if security-scan.yml already exists via API
  # -------------------------------------------------------------------------
  if gitea_api GET "/repos/${GITEA_ORG_NAME}/${repo}/contents/.gitea/workflows/security-scan.yml" >/dev/null 2>&1; then
    log_info "security-scan.yml already exists in ${repo} — skipping"
    SKIPPED=$((SKIPPED + 1))
    continue
  fi

  # -------------------------------------------------------------------------
  # Step 1: Clone the repo
  # -------------------------------------------------------------------------
  CLONE_DIR="${TEMP_BASE}/${repo}"
  rm -rf "$CLONE_DIR"
  mkdir -p "$CLONE_DIR"

  REPO_URL="${GITEA_BASE_URL}/${GITEA_ORG_NAME}/${repo}.git"
  log_info "Cloning ${repo}..."
  git_with_auth git clone -q "$REPO_URL" "$CLONE_DIR"

  # -------------------------------------------------------------------------
  # Step 2: Render security workflow template
  # The template references tool versions from .env so they're pinned
  # and reproducible across all repos.
  # -------------------------------------------------------------------------
  log_info "Rendering security-scan.yml..."
  mkdir -p "${CLONE_DIR}/.gitea/workflows"
  export SEMGREP_VERSION TRIVY_VERSION GITLEAKS_VERSION PROTECTED_BRANCH
  render_template "${SCRIPT_DIR}/templates/workflows/security-scan.yml.tpl" \
    "${CLONE_DIR}/.gitea/workflows/security-scan.yml" \
    "\${PROTECTED_BRANCH} \${SEMGREP_VERSION} \${TRIVY_VERSION} \${GITLEAKS_VERSION}"

  # -------------------------------------------------------------------------
  # Step 3: Commit and push
  # -------------------------------------------------------------------------
  cd "$CLONE_DIR"
  git config user.name "Gitea Migration"
  git config user.email "migration@gitea.local"
  git add .gitea/workflows/security-scan.yml
  git commit -q -m "Add security scanning workflow (Semgrep + Trivy + Gitleaks)"
  git_with_auth git push -q origin HEAD
  cd "$SCRIPT_DIR"

  log_success "Security workflow deployed to ${repo}"

  # -------------------------------------------------------------------------
  # Step 4: Update branch protection to require security status checks
  # Only if SECURITY_FAIL_ON_ERROR=true — this means PRs cannot be merged
  # unless all three security scans pass.
  # -------------------------------------------------------------------------
  if [[ "$SECURITY_FAIL_ON_ERROR" == "true" ]]; then
    log_info "Updating branch protection to require security checks..."

    # PATCH the existing branch protection to add status check contexts
    PATCH_PAYLOAD=$(jq -n '{
      enable_status_check: true,
      status_check_contexts: ["semgrep", "trivy", "gitleaks"]
    }')

    if gitea_api PATCH "/repos/${GITEA_ORG_NAME}/${repo}/branch_protections/${PROTECTED_BRANCH}" "$PATCH_PAYLOAD" >/dev/null 2>&1; then
      log_success "Branch protection updated with security status checks"
    else
      log_warn "Could not update branch protection — may need to be set manually"
    fi
  fi

  SUCCESS=$((SUCCESS + 1))
done

# ---------------------------------------------------------------------------
# Summary
# ---------------------------------------------------------------------------
printf '\n'
TOTAL=${#REPOS[@]}
log_info "Results: ${SUCCESS} deployed, ${SKIPPED} skipped, ${FAILED} failed (out of ${TOTAL})"

if [[ $FAILED -gt 0 ]]; then
  log_error "Some repos failed — check logs above"
  exit 1
fi

log_success "Phase 9 complete — security scanning deployed"