---

# Pre-checks

- name: Fail if Postgres not enabled
  fail:
    msg: "Postgres via the matrix-postgres role is not enabled (`matrix_postgres_enabled`). Cannot import."
  when: "not matrix_postgres_enabled|bool"

- name: Fail if playbook called incorrectly
  fail:
    msg: "The `nedb_database_path` variable needs to be provided to this playbook, via --extra-vars"
  when: "nedb_database_path is not defined or nedb_database_path.startswith('<')"

- name: Check if the provided nedb database file exists
  stat:
    path: "{{ nedb_database_path }}"
  register: nedb_database_path_stat_result

- name: Fail if provided SQLite database file doesn't exist
  fail:
    msg: "File cannot be found on the server at {{ nedb_database_path }}"
  when: "not nedb_database_path_stat_result.stat.exists"

# We either expect `postgres_db_connection_string` specifying a full Postgres database connection string,
# or `postgres_connection_string_variable_name`, specifying a name of a variable, which contains a valid connection string.

- block:
    - name: Fail if postgres_connection_string_variable_name points to an undefined variable
      fail: msg="postgres_connection_string_variable_name is defined, but there is no variable with the name `{{ postgres_connection_string_variable_name }}`"
      when: "postgres_connection_string_variable_name not in vars"

    - name: Get Postgres connection string from variable
      set_fact:
        postgres_db_connection_string: "{{ lookup('vars', postgres_connection_string_variable_name) }}"
  when: 'postgres_connection_string_variable_name is defined'

- name: Fail if playbook called incorrectly
  fail:
    msg: >-
      Either a `postgres_db_connection_string` variable or a `postgres_connection_string_variable_name` needs to be provided to this playbook, via `--extra-vars`.
      Example: `--extra-vars="postgres_db_connection_string=postgresql://username:password@localhost:<port>/database_name"` or `--extra-vars="postgres_connection_string_variable_name=matrix_appservice_discord_database_connString"`
  when: "postgres_db_connection_string is not defined or not postgres_db_connection_string.startswith('postgresql://')"


# Defaults

- name: Set postgres_start_wait_time, if not provided
  set_fact:
    postgres_start_wait_time: 15
  when: "postgres_start_wait_time|default('') == ''"


# Actual import work

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

- name: Wait a bit, so that Postgres can start
  wait_for:
    timeout: "{{ postgres_start_wait_time }}"
  delegate_to: 127.0.0.1
  become: false
  when: "matrix_postgres_service_start_result.changed|bool"

# No migration.sh available, but found this:
# https://github.com/matrix-org/matrix-appservice-slack/blob/develop/src/scripts/migrateToPostgres.ts
# Usage should be similar to appservice_irc
- name: Import appservice_slack NeDB database from {{ sqlite_database_path }} into Postgres
  when: database == 'appservice_slack'
  command:
    cmd: >-
      {{ matrix_host_command_docker }} run
      --rm
      --user={{ matrix_user_uid }}:{{ matrix_user_gid }}
      --cap-drop=ALL
      --network={{ matrix_docker_network }}
      --mount type=bind,src={{ matrix_appservice_irc_data_path }},dst=/data,ro
      --entrypoint=/bin/sh
      {{ matrix_appservice_slack_docker_image }}
      -c
      'node /lib/scripts/migrate-db-to-pgres.js -d /data -p passkey.pem -c {{ postgres_db_connection_string }}'


- name: Inject result
  set_fact:
    matrix_playbook_runtime_results: |
      {{
        matrix_playbook_runtime_results|default([])
        +
        [
          "NOTE: Your NeDB database file has been imported into Postgres. The original directory has been moved from `{{ nedb_database_path }}` to `{{ nedb_database_path }}.backup`. When you've confirmed that the import went well and everything works, you should be able to safely delete this file."
        ]
      }}