//! Tauri commands for the ERPNext settings: read/save the configuration, test a connection and load the
//! lists the settings dropdowns need. The API secret never leaves this module: `erpnext_get_config` returns
//! `apiSecretSet` only, and every command resolves a blank secret to the stored one on the Rust side.
//! The push commands send issued invoices and payments (see `integrations::erpnext::push`); the database lock is
//! never held across a network call.

use crate::integrations::erpnext::client::ErpClient;
use crate::integrations::erpnext::config::{
    self, ErpnextConfig, ErpnextConfigInput, ErpnextConfigView,
};
use crate::integrations::erpnext::discovery::{
    self, ic_number_ok, ConnectionTest, ErpnextOptions, LocalFacts,
};
use crate::integrations::erpnext::push::{self, PaymentPushResult, PushResult};
use crate::integrations::SyncStatus;
use crate::AppState;
use rusqlite::Connection;
use tauri::State;

pub fn get_config_impl(conn: &Connection) -> Result<ErpnextConfigView, String> {
    Ok(config::load(conn)?.view())
}

/// Merges the form with the stored row (blank secret keeps the stored one) without saving.
pub fn resolve_config(
    conn: &Connection,
    input: ErpnextConfigInput,
) -> Result<ErpnextConfig, String> {
    let stored = config::load(conn)?;
    input.resolve(&stored)
}

pub fn save_config_impl(
    conn: &Connection,
    input: ErpnextConfigInput,
) -> Result<ErpnextConfigView, String> {
    let cfg = resolve_config(conn, input)?;
    config::save(conn, &cfg)?;
    Ok(cfg.view())
}

/// What the connection test needs from the local database.
pub fn local_facts(conn: &Connection) -> Result<LocalFacts, String> {
    let registration: String = conn
        .query_row(
            "SELECT gst_registration FROM app_settings WHERE id = 1",
            [],
            |r| r.get(0),
        )
        .map_err(|e| e.to_string())?;
    let mut stmt = conn
        .prepare("SELECT number FROM invoices ORDER BY id")
        .map_err(|e| e.to_string())?;
    let invalid_numbers = stmt
        .query_map([], |r| r.get::<_, String>(0))
        .map_err(|e| e.to_string())?
        .collect::<rusqlite::Result<Vec<_>>>()
        .map_err(|e| e.to_string())?
        .into_iter()
        .filter(|n| !ic_number_ok(n))
        .take(5)
        .collect();
    let next_number = conn
        .query_row(
            "SELECT prefix, padding, next_number FROM invoice_series WHERE is_active = 1 ORDER BY id DESC LIMIT 1",
            [],
            |r| Ok((r.get::<_, String>(0)?, r.get::<_, i64>(1)?, r.get::<_, i64>(2)?)),
        )
        .ok()
        .map(|(prefix, padding, next)| crate::db::format_number(&prefix, padding, next));
    Ok(LocalFacts {
        vendor_registered: registration != "unregistered",
        invalid_numbers,
        next_number,
    })
}

#[tauri::command]
pub fn erpnext_get_config(state: State<AppState>) -> Result<ErpnextConfigView, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    get_config_impl(&conn)
}

/// A blank `apiSecret` keeps the stored secret; a value replaces it; `clearSecret` removes it.
#[tauri::command]
pub fn erpnext_save_config(
    state: State<AppState>,
    config: ErpnextConfigInput,
) -> Result<ErpnextConfigView, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    save_config_impl(&conn, config)
}

/// Tests the form values as typed (saved or not). The database lock is released before any network call.
#[tauri::command]
pub async fn erpnext_test_connection(
    state: State<'_, AppState>,
    config: ErpnextConfigInput,
) -> Result<ConnectionTest, String> {
    let (cfg, local) = {
        let conn = state.db.lock().map_err(|e| e.to_string())?;
        (resolve_config(&conn, config)?, local_facts(&conn)?)
    };
    let client = ErpClient::from_config(&cfg)?;
    Ok(discovery::test_connection(&client, &cfg, &local).await?)
}

/// Loads the dropdown lists. Company-scoped lists use `config.company`.
#[tauri::command]
pub async fn erpnext_load_options(
    state: State<'_, AppState>,
    config: ErpnextConfigInput,
) -> Result<ErpnextOptions, String> {
    let cfg = {
        let conn = state.db.lock().map_err(|e| e.to_string())?;
        resolve_config(&conn, config)?
    };
    let client = ErpClient::from_config(&cfg)?;
    Ok(client.load_options(&cfg.company).await?)
}

/// A client for the saved settings, or a readable reason why there is none.
fn saved_client(state: &AppState) -> Result<ErpClient, String> {
    let cfg = {
        let conn = state.db.lock().map_err(|e| e.to_string())?;
        config::load(&conn)?
    };
    if cfg.base_url.trim().is_empty() || cfg.api_key.trim().is_empty() || !cfg.api_secret.is_set() {
        return Err(
            "ERPNext is not set up yet: enter the address, API key and API secret in Settings."
                .into(),
        );
    }
    Ok(ErpClient::from_config(&cfg)?)
}

/// Sends one issued invoice. `submit` omitted follows the "submit on push" setting. A failure comes back as a
/// result with `ok: false` (and is recorded), not as an `Err`.
#[tauri::command]
pub async fn erpnext_push_invoice(
    state: State<'_, AppState>,
    id: i64,
    submit: Option<bool>,
) -> Result<PushResult, String> {
    let http = saved_client(&state)?;
    Ok(push::push_invoice(&state.db, &state.local_data_dir, &http, id, submit).await)
}

/// Sends several invoices one after another; one row's failure never stops the others.
#[tauri::command]
pub async fn erpnext_push_invoices(
    state: State<'_, AppState>,
    ids: Vec<i64>,
    submit: Option<bool>,
) -> Result<Vec<PushResult>, String> {
    let http = saved_client(&state)?;
    Ok(push::push_invoices(&state.db, &state.local_data_dir, &http, &ids, submit).await)
}

#[tauri::command]
pub async fn erpnext_push_payment(
    state: State<'_, AppState>,
    payment_id: i64,
) -> Result<PaymentPushResult, String> {
    let http = saved_client(&state)?;
    Ok(push::push_payment(&state.db, &http, payment_id).await)
}

#[tauri::command]
pub fn erpnext_sync_status(state: State<AppState>, id: i64) -> Result<SyncStatus, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    push::sync_status(&conn, id)
}

/// The sync state of every invoice that has one, for the History list.
#[tauri::command]
pub fn erpnext_sync_statuses(state: State<AppState>) -> Result<Vec<SyncStatus>, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    push::sync_statuses(&conn)
}

/// `<base>/app/sales-invoice/<name>` for an invoice that was sent.
#[tauri::command]
pub fn erpnext_open_url(state: State<AppState>, id: i64) -> Result<String, String> {
    let conn = state.db.lock().map_err(|e| e.to_string())?;
    push::open_url(&conn, id)
}

#[cfg(test)]
mod tests {
    use super::*;
    use serde_json::json;

    fn input(extra: serde_json::Value) -> ErpnextConfigInput {
        let mut base =
            json!({ "baseUrl": "https://erp.example.com", "apiKey": "key1", "company": "Test Co" });
        base.as_object_mut()
            .unwrap()
            .extend(extra.as_object().unwrap().clone());
        serde_json::from_value(base).unwrap()
    }

    #[test]
    fn saved_config_is_returned_without_the_secret() {
        let conn = crate::db::open_in_memory().unwrap();
        let view = save_config_impl(
            &conn,
            input(json!({ "apiSecret": "super-secret-value", "submitOnPush": true })),
        )
        .unwrap();
        assert!(view.api_secret_set);
        let shown = serde_json::to_string(&get_config_impl(&conn).unwrap()).unwrap();
        assert!(!shown.contains("super-secret-value"));
        assert!(shown.contains("\"apiSecretSet\":true"));
        assert!(shown.contains("\"company\":\"Test Co\""));

        // Saving again with a blank secret keeps it for the connection test too.
        save_config_impl(&conn, input(json!({ "company": "Other Co" }))).unwrap();
        let resolved = resolve_config(&conn, input(json!({}))).unwrap();
        assert_eq!(resolved.api_secret.expose(), "super-secret-value");
        assert_eq!(resolved.company, "Test Co");
    }

    #[test]
    fn test_values_are_resolved_without_saving() {
        let conn = crate::db::open_in_memory().unwrap();
        let resolved =
            resolve_config(&conn, input(json!({ "apiSecret": "typed-not-saved" }))).unwrap();
        assert_eq!(resolved.api_secret.expose(), "typed-not-saved");
        assert!(!get_config_impl(&conn).unwrap().api_secret_set);
    }

    #[test]
    fn local_facts_report_registration_numbers_and_the_next_number() {
        let conn = crate::db::open_in_memory().unwrap();
        let facts = local_facts(&conn).unwrap();
        assert!(!facts.vendor_registered);
        assert!(facts.invalid_numbers.is_empty());
        assert!(facts.next_number.is_some());

        conn.execute("UPDATE app_settings SET gst_registration = 'regular'", [])
            .unwrap();
        conn.execute(
            "INSERT INTO invoices (number, invoice_date, created_at, updated_at)
             VALUES ('INV/2026-001', '2026-04-01', 'n', 'n'), ('INVOICE/2026/000001', '2026-04-01', 'n', 'n')",
            [],
        )
        .unwrap();
        let facts = local_facts(&conn).unwrap();
        assert!(facts.vendor_registered);
        assert_eq!(facts.invalid_numbers, ["INVOICE/2026/000001"]);
    }
}