//! The Flow variables panel (hub spec §13.2, oxygenhub#102) shared by
//! the administration, organisation and repository settings pages: the
//! level's own variables and the ones it inherits.

use crate::auth::Viewer;
use crate::db::accounts;
use crate::levels::At;
use crate::variables::{self, Seen};
use crate::Shared;
use serde::Deserialize;

#[derive(Deserialize)]
pub struct VariableForm {
    #[serde(rename = "_csrf")]
    pub csrf_token: String,
    #[serde(default)]
    action: String,
    #[serde(default)]
    name: String,
    #[serde(default)]
    value: String,
}

/// Everything the panel shows.
pub struct Panel {
    /// The level's own variables.
    pub own: Vec<Seen>,
    /// The ones the levels above provide, outermost first.
    pub inherited: Vec<Seen>,
}

pub async fn panel(app: &Shared, at: &At) -> sqlx::Result<Panel> {
    let (own, inherited): (Vec<_>, Vec<_>) =
        variables::seen(&app.db, at.scope, &at.owner).await?.into_iter().partition(|v| v.from.is_empty());
    Ok(Panel { own, inherited })
}

/// Apply the panel's form: `Ok(notice)` or `Err(message for the user)`.
pub async fn apply(app: &Shared, viewer: &Viewer, at: &At, f: VariableForm) -> sqlx::Result<Result<String, String>> {
    let name = f.name.trim();
    if !variables::name_ok(name) {
        return Ok(Err(
            "A variable's name is a letter or _, then letters, digits and _, up to 64, and not FLOW_… (Flow sets those).".into()
        ));
    }
    Ok(Ok(match f.action.as_str() {
        "set" => {
            let value = f.value.replace("\r\n", "\n");
            if !variables::value_ok(&value) {
                return Ok(Err(format!("A value is up to {} characters of text.", variables::MAX_VALUE)));
            }
            let own = variables::list(&app.db, at.scope).await?;
            if own.len() >= variables::MAX_PER_LEVEL && !own.iter().any(|v| v.name == name) {
                return Ok(Err(format!("Up to {} variables here.", variables::MAX_PER_LEVEL)));
            }
            variables::set(&app.db, at.scope, name, &value).await?;
            accounts::audit(&app.db, viewer.account(), "flow.variable.set", &at.label, name).await.ok();
            format!("{name} set.")
        }
        "delete" => {
            if !variables::delete(&app.db, at.scope, name).await? {
                return Ok(Err(format!("There is no variable {name} here.")));
            }
            accounts::audit(&app.db, viewer.account(), "flow.variable.deleted", &at.label, name).await.ok();
            format!("{name} removed.")
        }
        _ => return Ok(Err("Unknown action.".into())),
    }))
}