apiVersion: batch/v1
kind: Job
metadata:
  name: clickhouse-db-init
  labels:
    app.kubernetes.io/name: clickhouse-db-init
    app.kubernetes.io/instance: {{ .Release.Name }}
  annotations:
    checksum/config: {{ include (print $.Template.BasePath "/init-sql-configmap.yaml") . | sha256sum }}
spec:
  template:
    spec:
      restartPolicy: OnFailure
      containers:
        - name: clickhouse-init
          image: clickhouse/clickhouse-server:{{ .Chart.AppVersion }}
          command: ["bash", "-c"]
          args:
            - |
              echo "⏳ Waiting for ClickHouse..."
              until clickhouse-client \
                --host {{ .Values.clickhouse.host }} \
                --port {{ .Values.clickhouse.port }} \
                --user {{ .Values.clickhouse.adminUser }} \
                --password "{{ .Values.clickhouse.adminPassword }}" \
                -q "SELECT 1" >/dev/null 2>&1; do
                sleep 2
              done
              echo "✅ ClickHouse ready"

              {{- if .Values.databases }}
              echo "➡️ Creating declared databases & users..."
              clickhouse-client \
                --host {{ .Values.clickhouse.host }} \
                --port {{ .Values.clickhouse.port }} \
                --user {{ .Values.clickhouse.adminUser }} \
                --password "{{ .Values.clickhouse.adminPassword }}" \
                --multiquery < /config/init.sql
              {{- end }}

              echo "➡️ Generating list of databases to drop..."
              clickhouse-client \
                --host {{ .Values.clickhouse.host }} \
                --port {{ .Values.clickhouse.port }} \
                --user {{ .Values.clickhouse.adminUser }} \
                --password "{{ .Values.clickhouse.adminPassword }}" \
                -q "
                  SELECT concat('DROP DATABASE IF EXISTS ', name, ';')
                  FROM system.databases
                  WHERE name NOT IN (
                    'system',
                    'information_schema',
                    'INFORMATION_SCHEMA',
                    'default'
                    {{- if .Values.databases }}
                      {{- range $db := .Values.databases }}
                        , '{{ $db }}'
                      {{- end }}
                    {{- end }}
                  );
                " > /tmp/to_drop.sql

              if [ -s /tmp/to_drop.sql ]; then
                echo "➡️ Dropping leftover databases:"
                cat /tmp/to_drop.sql

                clickhouse-client \
                  --host {{ .Values.clickhouse.host }} \
                  --port {{ .Values.clickhouse.port }} \
                  --user {{ .Values.clickhouse.adminUser }} \
                  --password "{{ .Values.clickhouse.adminPassword }}" \
                  --multiquery < /tmp/to_drop.sql

              else
                echo "✔️ No databases to drop."
              fi

              echo "🎉 Initialization completed"
          volumeMounts:
            - name: init-sql
              mountPath: /config
      volumes:
        - name: init-sql
          configMap:
            name: clickhouse-init-sql