#!/bin/bash
#==============================================================#
# File      :   check-db
# Desc      :   Check source database definition
# Time      :   {{ '%Y-%m-%d %H:%M' |strftime }}
# Path      :   {{ dir_path }}/check-db
# Deps      :   bash
# License   :   Apache-2.0 @ https://pigsty.io/docs/about/license/
# Copyright :   2018-2026  Ruohang Feng / Vonng (rh@vonng.com)
#==============================================================#


#--------------------------------------------------------------#
# Utils
#--------------------------------------------------------------#
__CN='\033[0m';__CK='\033[0;30m';__CR='\033[0;31m';__CG='\033[0;32m';
__CY='\033[0;33m';__CB='\033[0;34m';__CM='\033[0;35m';__CC='\033[0;36m';__CW='\033[0;37m';
function log_info() {  printf "[${__CG} OK ${__CN}] ${__CG}$*${__CN}\n";   }
function log_warn() {  printf "[${__CY}WARN${__CN}] ${__CY}$*${__CN}\n";   }
function log_error() { printf "[${__CR}FAIL${__CN}] ${__CR}$*${__CN}\n";   }
function log_debug() { printf "[${__CB}HINT${__CN}] ${__CB}$*${__CN}\n"; }
function log_input() { printf "[${__CM} IN ${__CN}] ${__CM}$*\n=> ${__CN}"; }
function log_hint()  { printf "${__CB}$*${__CN}\n"; }
function log_line()  { printf "${__CM}[$*] ===========================================${__CN}\n"; }


#--------------------------------------------------------------#
# Param
#--------------------------------------------------------------#
# check if MIGRATION_CONTEXT is defined as expected
EXPECTED_CONTEXT="{{ src_cls }}.{{ src_db }}"
if [[ "${MIGRATION_CONTEXT}" != "${EXPECTED_CONTEXT}" ]]; then
    log_error "MIGRATION_CONTEXT = ${MIGRATION_CONTEXT} != EXPECTED ${EXPECTED_CONTEXT}"
    log_hint "did you run . activate first?"
    exit 1
fi
OUTPUT="data/pg_databases.json"


#--------------------------------------------------------------#
# Execute
#--------------------------------------------------------------#
log_info   "check src databases: ${SRCCLS}.${SRCDB}"
log_info   "  - SRC URL : ${SRCPG}"
log_info   "  - OUTPUT  : ${OUTPUT}"

psql "${SRCPG}" -AXwto ${OUTPUT} <<-EOF

-- generate json output of cluster databases
SELECT jsonb_build_object('pg_databases', jsonb_agg(row_to_json(final)::JSONB))
FROM (SELECT datname                       AS name,
             datdba::RegRole::Text         AS owner,
             pg_encoding_to_char(encoding) AS encoding,
             datcollate                    AS lc_collate,
             datctype                      AS lc_ctype,
             datallowconn                  AS allowconn,
             datconnlimit                  AS connlimit,
             (SELECT json_agg(nspname) AS schemas
              FROM pg_namespace
              WHERE nspname !~ '^pg_'
                AND nspname !~ '^_'
                AND nspname !~ '^timescaledb'
                AND nspname !~ '^citus'
                AND nspname !~ '^columnar'
                AND nspname NOT IN ('pg_catalog', 'information_schema', 'pg_toast', 'repack', 'monitor')),
             (SELECT json_agg(row_to_json(ex)) AS extensions
              FROM (SELECT extname AS name, extnamespace::RegNamespace AS schema
                    FROM pg_extension
                    WHERE extname NOT IN
                          ('plpgsql', 'adminpack', 'pg_stat_statements', 'pgstattuple', 'pg_buffercache', 'pageinspect',
                           'pg_prewarm', 'pg_visibility', 'pg_freespacemap', 'postgres_fdw', 'file_fdw', 'btree_gist',
                           'btree_gin', 'pg_trgm', 'intagg', 'intarray', 'pg_repack')) ex),
             (SELECT json_object_agg(substring(cfg, 0, strpos(cfg, '=')),
                                     substring(cfg, strpos(cfg, '=') + 1)) AS parameters
              FROM (SELECT unnest(setconfig) AS cfg
                    FROM pg_db_role_setting s
                             JOIN pg_database d ON d.oid = s.setdatabase
                    WHERE d.datname = current_database()) cf)
      FROM pg_database
      WHERE datname = current_database()) final;

EOF


# print result in yaml format
log_info "check-db result:\n"
python3 -c "import json,yaml; print(yaml.dump(json.load(open('${OUTPUT}'))))"

# alternative: cat ${OUTPUT}  | jq   | yq eval -P
