use anyhow::Result;
use askama::Template;
use derive_builder::Builder;
use interim_models::{client::AppDbClient, portal::Portal, workspace::Workspace};
use interim_pgtypes::{
    client::WorkspaceClient,
    pg_class::{PgClass, PgRelKind},
};
use sqlx::postgres::types::Oid;
use uuid::Uuid;

use crate::navigator::Navigator;

#[derive(Builder, Clone, Debug, Template)]
#[template(path = "workspace_nav.html")]
pub(crate) struct WorkspaceNav {
    workspace: Workspace,
    relations: Vec<RelationItem>,
    #[builder(default, setter(strip_option))]
    current: Option<NavLocation>,
    navigator: Navigator,
}

impl WorkspaceNav {
    pub fn builder() -> WorkspaceNavBuilder {
        WorkspaceNavBuilder::default()
    }
}

#[derive(Clone, Debug)]
pub struct RelationItem {
    pub name: String,
    pub oid: Oid,
    pub portals: Vec<PortalItem>,
}

#[derive(Clone, Debug)]
pub struct PortalItem {
    pub name: String,
    pub id: Uuid,
}

#[derive(Clone, Debug, PartialEq)]
pub enum NavLocation {
    Rel(Oid, Option<RelLocation>),
}

#[derive(Clone, Debug, PartialEq)]
pub enum RelLocation {
    Portal(Uuid),
    Sharing,
}

impl WorkspaceNavBuilder {
    /// Helper function to populate relations and lenses automatically.
    /// [`WorkspaceNavBuilder::workspace()`] must be called first, or else this
    /// method will return an error.
    pub async fn populate_rels(
        &mut self,
        app_db: &mut AppDbClient,
        workspace_client: &mut WorkspaceClient,
    ) -> Result<&mut Self> {
        let rels = PgClass::with_kind_in([PgRelKind::OrdinaryTable])
            .fetch_all(workspace_client)
            .await?;
        let mut rel_items = Vec::with_capacity(rels.len());
        for rel in rels {
            if rel.regnamespace.as_str() != "pg_catalog"
                && rel.regnamespace.as_str() != "information_schema"
            {
                let portals = Portal::belonging_to_workspace(
                    self.workspace
                        .as_ref()
                        .ok_or(WorkspaceNavBuilderError::UninitializedField("workspace"))?
                        .id,
                )
                .belonging_to_rel(rel.oid)
                .fetch_all(app_db)
                .await?;
                rel_items.push(RelationItem {
                    name: rel.relname,
                    oid: rel.oid,
                    portals: portals
                        .into_iter()
                        .map(|portal| PortalItem {
                            name: portal.name,
                            id: portal.id,
                        })
                        .collect(),
                });
            }
        }
        Ok(self.relations(rel_items))
    }
}