#!/usr/bin/env sh
set -eu

log() { echo "[vault-k8s-auth] $*"; }

ensure_token() {
  if [ -n "${VAULT_TOKEN:-}" ]; then
    return
  fi
  role="${VAULT_K8S_ROLE:-vault}"
  jwt="$(cat /var/run/secrets/kubernetes.io/serviceaccount/token)"
  if ! VAULT_TOKEN="$(vault write -field=token auth/kubernetes/login role="${role}" jwt="${jwt}")"; then
    log "kubernetes auth login failed; set VAULT_TOKEN or fix role ${role}"
    exit 1
  fi
  export VAULT_TOKEN
}

status_json="$(vault status -format=json || true)"
if [ -z "${status_json}" ]; then
  log "vault status failed; check VAULT_ADDR and VAULT_TOKEN"
  exit 1
fi

if ! printf '%s' "${status_json}" | grep -q '"initialized":[[:space:]]*true'; then
  log "vault not initialized; skipping"
  exit 0
fi

if printf '%s' "${status_json}" | grep -q '"sealed":[[:space:]]*true'; then
  log "vault sealed; skipping"
  exit 0
fi

ensure_token

k8s_host="https://${KUBERNETES_SERVICE_HOST}:443"
k8s_ca="$(cat /var/run/secrets/kubernetes.io/serviceaccount/ca.crt)"
k8s_token="$(cat /var/run/secrets/kubernetes.io/serviceaccount/token)"
role_ttl="${VAULT_K8S_ROLE_TTL:-1h}"
token_reviewer_jwt="${VAULT_K8S_TOKEN_REVIEWER_JWT:-}"

if [ -z "${token_reviewer_jwt}" ] && [ -n "${VAULT_K8S_TOKEN_REVIEWER_JWT_FILE:-}" ] && [ -r "${VAULT_K8S_TOKEN_REVIEWER_JWT_FILE}" ]; then
  token_reviewer_jwt="$(cat "${VAULT_K8S_TOKEN_REVIEWER_JWT_FILE}")"
fi
if [ -z "${token_reviewer_jwt}" ]; then
  token_reviewer_jwt="${k8s_token}"
fi

if ! vault auth list -format=json | grep -q '"kubernetes/"'; then
  log "enabling kubernetes auth"
  vault auth enable kubernetes
fi

log "configuring kubernetes auth"
vault write auth/kubernetes/config \
  token_reviewer_jwt="${token_reviewer_jwt}" \
  kubernetes_host="${k8s_host}" \
  kubernetes_ca_cert="${k8s_ca}"

write_raw_policy() {
  name="$1"
  body="$2"
  log "writing policy ${name}"
  printf '%s\n' "${body}" | vault policy write "${name}" -
}

write_policy_and_role() {
  role="$1"
  namespace="$2"
  service_accounts="$3"
  read_paths="$4"
  write_paths="$5"

  policy_body=""
  for path in ${read_paths}; do
    policy_body="${policy_body}
path \"kv/data/atlas/${path}\" {
  capabilities = [\"read\"]
}
path \"kv/metadata/atlas/${path}\" {
  capabilities = [\"list\"]
}
"
  done
  for path in ${write_paths}; do
    policy_body="${policy_body}
path \"kv/data/atlas/${path}\" {
  capabilities = [\"create\", \"update\", \"read\"]
}
path \"kv/metadata/atlas/${path}\" {
  capabilities = [\"list\"]
}
"
  done

  log "writing policy ${role}"
  printf '%s\n' "${policy_body}" | vault policy write "${role}" -

  log "writing role ${role}"
  vault write "auth/kubernetes/role/${role}" \
    bound_service_account_names="${service_accounts}" \
    bound_service_account_namespaces="${namespace}" \
    policies="${role}" \
    ttl="${role_ttl}"
}

vault_admin_policy='
path "sys/auth" {
  capabilities = ["read"]
}
path "sys/auth/*" {
  capabilities = ["create", "update", "delete", "sudo", "read"]
}
path "auth/kubernetes/*" {
  capabilities = ["create", "update", "read"]
}
path "auth/oidc/*" {
  capabilities = ["create", "update", "read"]
}
path "sys/policies/acl" {
  capabilities = ["list"]
}
path "sys/policies/acl/*" {
  capabilities = ["create", "update", "read"]
}
path "sys/internal/ui/mounts" {
  capabilities = ["read"]
}
path "sys/mounts" {
  capabilities = ["read"]
}
path "sys/mounts/auth/*" {
  capabilities = ["read", "update", "sudo"]
}
path "kv/data/atlas/vault/*" {
  capabilities = ["read"]
}
path "kv/metadata/atlas/vault/*" {
  capabilities = ["list"]
}
path "kv/data/*" {
  capabilities = ["create", "update", "read", "delete", "patch"]
}
path "kv/metadata" {
  capabilities = ["list"]
}
path "kv/metadata/*" {
  capabilities = ["read", "list", "delete"]
}
path "kv/data/atlas/shared/*" {
  capabilities = ["create", "update", "read", "patch"]
}
path "kv/metadata/atlas/shared/*" {
  capabilities = ["list"]
}
'

write_raw_policy "vault-admin" "${vault_admin_policy}"
dev_kv_policy='
path "kv/metadata" {
  capabilities = ["list"]
}
path "kv/metadata/atlas" {
  capabilities = ["list"]
}
path "kv/metadata/atlas/shared" {
  capabilities = ["list"]
}
path "kv/metadata/atlas/shared/*" {
  capabilities = ["list"]
}
path "kv/data/atlas/shared/*" {
  capabilities = ["read"]
}
'
write_raw_policy "dev-kv" "${dev_kv_policy}"
log "writing role vault-admin"
vault write "auth/kubernetes/role/vault-admin" \
  bound_service_account_names="vault-admin" \
  bound_service_account_namespaces="vault" \
  policies="vault-admin" \
  ttl="${role_ttl}"

write_policy_and_role "outline" "outline" "outline-vault" \
  "outline/* shared/postmark-relay" ""
write_policy_and_role "planka" "planka" "planka-vault" \
  "planka/* shared/postmark-relay" ""
write_policy_and_role "bstein-dev-home" "bstein-dev-home" "bstein-dev-home,bstein-dev-home-vault-sync" \
  "portal/* shared/chat-ai-keys-runtime shared/portal-e2e-client harbor-pull/bstein-dev-home" ""
write_policy_and_role "gitea" "gitea" "gitea-vault" \
  "gitea/*" ""
write_policy_and_role "vaultwarden" "vaultwarden" "vaultwarden-vault" \
  "vaultwarden/* shared/postmark-relay" ""
write_policy_and_role "sso" "sso" "sso-vault,sso-vault-sync,mas-secrets-ensure" \
  "sso/* portal/bstein-dev-home-keycloak-admin shared/keycloak-admin shared/portal-e2e-client shared/postmark-relay harbor-pull/sso" ""
write_policy_and_role "mailu-mailserver" "mailu-mailserver" "mailu-vault-sync" \
  "mailu/* shared/postmark-relay harbor-pull/mailu-mailserver" ""
write_policy_and_role "harbor" "harbor" "harbor-vault-sync" \
  "harbor/* harbor-pull/harbor" ""
write_policy_and_role "nextcloud" "nextcloud" "nextcloud-vault" \
  "nextcloud/* shared/keycloak-admin shared/postmark-relay" ""
write_policy_and_role "comms" "comms" "comms-vault,atlasbot" \
  "comms/* shared/chat-ai-keys-runtime harbor-pull/comms" ""
write_policy_and_role "jenkins" "jenkins" "jenkins" \
  "jenkins/*" ""
write_policy_and_role "monitoring" "monitoring" "monitoring-vault-sync" \
  "monitoring/* shared/postmark-relay harbor-pull/monitoring" ""
write_policy_and_role "logging" "logging" "logging-vault-sync" \
  "logging/* harbor-pull/logging" ""
write_policy_and_role "pegasus" "jellyfin" "pegasus-vault-sync" \
  "pegasus/* harbor-pull/jellyfin" ""
write_policy_and_role "crypto" "crypto" "crypto-vault-sync" \
  "crypto/* harbor-pull/crypto" ""
write_policy_and_role "health" "health" "health-vault-sync" \
  "health/*" ""
write_policy_and_role "longhorn" "longhorn-system" "longhorn-vault" \
  "longhorn/*" ""
write_policy_and_role "postgres" "postgres" "postgres-vault" \
  "postgres/postgres-db" ""
write_policy_and_role "vault" "vault" "vault" \
  "vault/*" ""

write_policy_and_role "sso-secrets" "sso" "mas-secrets-ensure" \
  "shared/keycloak-admin" \
  "harbor/harbor-oidc vault/vault-oidc-config comms/synapse-oidc logging/oauth2-proxy-logs-oidc"
write_policy_and_role "crypto-secrets" "crypto" "crypto-secrets-ensure" \
  "" \
  "crypto/wallet-monero-temp-rpc-auth"
write_policy_and_role "comms-secrets" "comms" \
  "comms-secrets-ensure,mas-db-ensure,mas-admin-client-secret-writer,othrys-synapse-signingkey-job" \
  "" \
  "comms/turn-shared-secret comms/livekit-api comms/synapse-redis comms/synapse-macaroon comms/atlasbot-credentials-runtime comms/synapse-db comms/mas-db comms/mas-admin-client-runtime comms/mas-secrets-runtime comms/othrys-synapse-signingkey"