---

- name: Set default postgres_dump_dir, if not provided
  set_fact:
    postgres_dump_dir: "/tmp"
  when: "postgres_dump_dir|default('') == ''"

- name: Set postgres_dump_name, if not provided
  set_fact:
    postgres_dump_name: "matrix-postgres.out"
  when: "postgres_dump_name|default('') == ''"

- set_fact:
    postgres_auto_upgrade_backup_data_path: "{{ matrix_postgres_data_path }}-auto-upgrade-backup"

- name: Fail, if trying to upgrade external Postgres database
  fail:
    msg: "Your configuration indicates that you're using an external Postgres database. Refusing to try and upgrade that."
  when: "matrix_postgres_use_external"

- name: Check Postgres auto-upgrade backup data directory
  stat:
    path: "{{ postgres_auto_upgrade_backup_data_path }}"
  register: result_auto_upgrade_path

- name: Abort, if existing Postgres auto-upgrade data path detected
  fail:
    msg: "Detected that a left-over {{ postgres_auto_upgrade_backup_data_path }} exists. You should rename it to {{ matrix_postgres_data_path }} if the previous upgrade went wrong, or delete it if it went well."
  when: "result_auto_upgrade_path.stat.exists"

- name: Determine existing Postgres version (check PG_VERSION file)
  stat:
    path: "{{ matrix_postgres_data_path }}/PG_VERSION"
  register: result_pg_version_stat

- name: Abort, if no existing Postgres version detected
  fail: msg="Could not find existing Postgres installation"
  when: "not result_pg_version_stat.stat.exists"

- name: Determine existing Postgres version (read PG_VERSION file)
  slurp:
    src: "{{ matrix_postgres_data_path }}/PG_VERSION"
  register: result_pg_version

- name: Determine existing Postgres version (default to empty)
  set_fact:
    pg_version: ""

- name: Determine existing Postgres version (make sense of PG_VERSION file)
  set_fact:
    pg_version: "{{ result_pg_version['content']|b64decode|replace('\n', '') }}"

- name: Determine Postgres version to use (default to latest)
  set_fact:
    matrix_postgres_docker_image_to_use: "{{ matrix_postgres_docker_image_latest }}"

- name: Determine Postgres version to use (use 9.x, if detected)
  set_fact:
    matrix_postgres_docker_image_to_use: "{{ matrix_postgres_docker_image_v9 }}"
  when: "pg_version.startswith('9.')"

- name: Abort, if already at latest Postgres version
  fail: msg="You are already running the latest Postgres version supported. Nothing to do"
  when: "matrix_postgres_docker_image_to_use == matrix_postgres_docker_image_latest"

- name: Ensure matrix-synapse is stopped
  service: name=matrix-synapse state=stopped

- name: Ensure matrix-postgres is started
  service: name=matrix-postgres state=started daemon_reload=yes

- name: Wait a bit, so that Postgres can start
  wait_for:
    timeout: 5
  delegate_to: 127.0.0.1
  become: false

- name: Perform Postgres database dump
  command: |
    /usr/bin/docker run --rm --name matrix-postgres-dump \
    --link matrix-postgres:postgres \
    --env-file={{ matrix_environment_variables_data_path }}/env-postgres-pgsql-docker \
    -v {{ postgres_dump_dir }}:/out \
    {{ matrix_postgres_docker_image_to_use }} pg_dump -h postgres {{ matrix_postgres_db_name }} -f /out/{{ postgres_dump_name }}

- name: Ensure matrix-postgres is stopped
  service: name=matrix-postgres state=stopped

- name: Rename existing Postgres data directory
  command: "mv {{ matrix_postgres_data_path }} {{ postgres_auto_upgrade_backup_data_path }}"

- debug:
    msg: "NOTE: Your Postgres data directory has been moved from `{{ matrix_postgres_data_path }}` to `{{ postgres_auto_upgrade_backup_data_path }}`. In the event of failure, you can move it back and run the playbook with --tags=setup-postgres to restore operation."

- include: tasks/setup/setup_postgres.yml

- name: Ensure matrix-postgres autoruns and is restarted
  service: name=matrix-postgres enabled=yes state=restarted daemon_reload=yes

- name: Wait a bit, so that Postgres can start
  wait_for:
    timeout: 5
  delegate_to: 127.0.0.1
  become: false

- name: Perform Postgres database import
  command: |
    /usr/bin/docker run --rm --name matrix-postgres-import \
    --link matrix-postgres:postgres \
    --env-file={{ matrix_environment_variables_data_path }}/env-postgres-pgsql-docker \
    -v {{ postgres_dump_dir }}:/in:ro \
    {{ matrix_postgres_docker_image_latest }} psql -h postgres -f /in/{{ postgres_dump_name }}

- name: Delete Postgres database dump file
  file:
    path: "{{ postgres_dump_dir }}/{{ postgres_dump_name }}"
    state: absent

- name: Ensure matrix-synapse is started
  service: name=matrix-synapse state=started daemon_reload=yes

- debug:
    msg: "NOTE: Your old Postgres data directory is preserved at `{{ postgres_auto_upgrade_backup_data_path }}`. You might want to get rid of it once you've confirmed that all is well."