sql-gen 0.2.3

use std::collections::HashMap;

use sqlx::PgPool;

use crate::{
    core::models::db::{CustomEnum, CustomEnumVariant},
    postgres::models::postgres_enum::PostgresEnumRow,
};

pub async fn get_postgres_enums(pool: &PgPool) -> Result<Vec<CustomEnum>, sqlx::Error> {
    let query = r"
        SELECT
            n.nspname AS schema,
            t.typname AS enum_type,
            e.enumlabel AS enum_value,
            d.description AS enum_type_comment
        FROM
            pg_type t
            JOIN pg_enum e ON t.oid = e.enumtypid
            JOIN pg_catalog.pg_namespace n ON n.oid = t.typnamespace
            LEFT JOIN pg_description d
                ON d.objoid = t.oid AND d.objsubid = 0
        WHERE
            n.nspname NOT IN ('pg_catalog', 'information_schema')
        ORDER BY
            schema, enum_type, e.enumsortorder;
    ";

    let rows: Vec<PostgresEnumRow> = sqlx::query_as::<_, PostgresEnumRow>(query)
        .fetch_all(pool)
        .await?;

    let mut enum_map: HashMap<(String, String, Option<String>), Vec<String>> = HashMap::new();

    for row in rows {
        enum_map
            .entry((
                row.schema.clone(),
                row.enum_type.clone(),
                row.enum_type_comment,
            ))
            .or_default()
            .push(row.enum_value);
    }

    let mut enums: Vec<CustomEnum> = Vec::new();

    for ((schema, name, enum_comment), variants) in enum_map {
        enums.push(CustomEnum {
            name: name.clone(),
            type_name: Some(name),
            schema: Some(schema),
            child_of_table: None,
            comments: enum_comment,
            variants: variants
                .into_iter()
                .map(|v| CustomEnumVariant { name: v })
                .collect(),
        });
    }

    Ok(enums)
}