#!/bin/bash

# File paths for output
OUTPUT_FILE="/tmp/datafile_usage.tmp"
PDB_LIST_FILE="/tmp/pdb_list.tmp"
> "$OUTPUT_FILE" # Clear the output file before starting
touch $OUTPUT_FILE
chown oracle $OUTPUT_FILE

# Function to execute the datafile usage query in a specific container
run_query() {
    local container_name="$1"
    su - oracle -s /bin/bash -c "
        sqlplus -s / as sysdba <<EOF >> \"$OUTPUT_FILE\"
        whenever sqlerror exit sql.sqlcode;

        SET ECHO ON
        SET HEADING ON
        SET UNDERLINE '='
        SET FEEDBACK OFF
        SET LINESIZE 200
        SET PAGESIZE 100
        COLUMN datafile_path FORMAT A50
        COLUMN tablespace_name FORMAT A20
        COLUMN allocated_mb FORMAT 9999999.99
        COLUMN used_mb FORMAT 9999999.99
        COLUMN free_mb FORMAT 9999999.99
        COLUMN pct_used FORMAT 999.99

        -- Switch to the specified container
        ALTER SESSION SET CONTAINER = $container_name;

        -- Print the container name for clarity
        PROMPT Datafile usage for container: $container_name;

        SELECT d.file_name AS datafile_path,
               d.tablespace_name,
               ROUND(d.bytes / 1024 / 1024, 2) AS allocated_mb,
               ROUND((d.bytes - NVL(fs.bytes, 0)) / 1024 / 1024, 2) AS used_mb,
               ROUND(NVL(fs.bytes, 0) / 1024 / 1024, 2) AS free_mb,
               ROUND(((d.bytes - NVL(fs.bytes, 0)) / d.bytes) * 100, 2) AS pct_used
          FROM dba_data_files d
          LEFT JOIN (
              SELECT file_id, SUM(bytes) AS bytes
              FROM dba_free_space
              GROUP BY file_id
          ) fs ON d.file_id = fs.file_id
         ORDER BY d.tablespace_name, d.file_name;

        exit;
EOF
    "
}

# Run the query for the CDB (root container)
echo "Gathering datafile usage for CDB (root container)..." >> "$OUTPUT_FILE"
run_query 'CDB\$ROOT'

# Get a list of all PDBs, excluding PDB$SEED, and write to a temporary file
su - oracle -s /bin/bash -c "
    sqlplus -s / as sysdba <<'EOF'
    set heading off
    set feedback off
    set pagesize 0
    spool $PDB_LIST_FILE
    SELECT NAME FROM v\$pdbs WHERE NAME NOT IN ('PDB\$SEED');
    spool off
    exit;
EOF
"

# Verify that the PDB_LIST_FILE was created and contains data
if [[ -f "$PDB_LIST_FILE" && -s "$PDB_LIST_FILE" ]]; then
    # Read each valid PDB name from the temporary file
    while IFS= read -r PDB; do
        PDB=$(echo "$PDB" | xargs)  # Trim any leading/trailing whitespace
        if [[ -n "$PDB" ]]; then
            echo "Gathering datafile usage for PDB: $PDB..." >> "$OUTPUT_FILE"
            run_query "$PDB"
        fi
    done < "$PDB_LIST_FILE"
else
    echo "No PDBs found or could not access v\$pdbs view" >> "$OUTPUT_FILE"
fi

# Clean up the temporary file
rm -f "$PDB_LIST_FILE"