// src/tables_data/handlers/get_table_data.rs
use tonic::Status;
use sqlx::{PgPool, Row};
use std::collections::HashMap;
use common::proto::multieko2::tables_data::{GetTableDataRequest, GetTableDataResponse};

pub async fn get_table_data(
    db_pool: &PgPool,
    request: GetTableDataRequest,
) -> Result<GetTableDataResponse, Status> {
    let profile_name = request.profile_name;
    let table_name = request.table_name;
    let record_id = request.id;

    // Lookup profile
    let profile = sqlx::query!(
        "SELECT id FROM profiles WHERE name = $1",
        profile_name
    )
    .fetch_optional(db_pool)
    .await
    .map_err(|e| Status::internal(format!("Profile lookup error: {}", e)))?;

    let profile_id = profile.ok_or_else(|| Status::not_found("Profile not found"))?.id;

    // Lookup table_definition
    let table_def = sqlx::query!(
        r#"SELECT id, columns FROM table_definitions
        WHERE profile_id = $1 AND table_name = $2"#,
        profile_id,
        table_name
    )
    .fetch_optional(db_pool)
    .await
    .map_err(|e| Status::internal(format!("Table lookup error: {}", e)))?;

    let table_def = table_def.ok_or_else(|| Status::not_found("Table not found"))?;

    // Parse user-defined columns from JSON
    let columns_json: Vec<String> = serde_json::from_value(table_def.columns.clone())
        .map_err(|e| Status::internal(format!("Column parsing error: {}", e)))?;

    let mut user_columns = Vec::new();
    for col_def in columns_json {
        let parts: Vec<&str> = col_def.splitn(2, ' ').collect();
        if parts.len() != 2 {
            return Err(Status::internal("Invalid column format"));
        }
        let name = parts[0].trim_matches('"').to_string();
        let sql_type = parts[1].to_string();
        user_columns.push((name, sql_type));
    }

    // Prepare all columns (system + user-defined)
    let system_columns = vec![
        ("id".to_string(), "BIGINT".to_string()),
        ("deleted".to_string(), "BOOLEAN".to_string()),
        ("firma".to_string(), "TEXT".to_string()),
    ];
    let all_columns: Vec<(String, String)> = system_columns
        .into_iter()
        .chain(user_columns.into_iter())
        .collect();

    // Build SELECT clause with COALESCE and type casting
    let columns_clause = all_columns
        .iter()
        .map(|(name, _)| format!("COALESCE(\"{0}\"::TEXT, '') AS \"{0}\"", name))
        .collect::<Vec<_>>()
        .join(", ");

    let sql = format!(
        "SELECT {} FROM \"{}\" WHERE id = $1 AND deleted = false",
        columns_clause, table_name
    );

    // Execute query
    let row = sqlx::query(&sql)
        .bind(record_id)
        .fetch_one(db_pool)
        .await
        .map_err(|e| match e {
            sqlx::Error::RowNotFound => Status::not_found("Record not found"),
            _ => Status::internal(format!("Database error: {}", e)),
        })?;

    // Build response data
    let mut data = HashMap::new();
    for (column_name, _) in &all_columns {
        let value: String = row
            .try_get(column_name.as_str())
            .map_err(|e| Status::internal(format!("Failed to get column {}: {}", column_name, e)))?;
        data.insert(column_name.clone(), value);
    }

    Ok(GetTableDataResponse { data })
}