toko-feed-cli 0.2.1

//! Canonical JSON backup, deliberately excluding provider evidence and operations.

use std::{fs, path::Path};

use serde::Serialize;
use serde_json::{Value, json};
use toko_feed::{CollectionView, PokemonCardView, PokemonSetView};

use super::{
    CliError, DEFAULT_MAX_PAGES, ListOptions, MAX_QUERY_LIMIT, Target, collect_keyset_pages,
    fetch_card_page, fetch_collection_page, fetch_set_page,
};

const CANONICAL_BACKUP_FORMAT_VERSION: u32 = 1;
pub const DEFAULT_CANONICAL_BACKUP_PATH: &str = "data/canonical.json";

#[derive(Debug, Serialize)]
struct CanonicalBackup {
    format_version: u32,
    collections: Vec<CollectionView>,
    pokemon_sets: Vec<PokemonSetView>,
    pokemon_cards: Vec<PokemonCardView>,
}

pub fn execute(target: &Target, path: &Path) -> Result<Value, CliError> {
    let options = ListOptions {
        limit: MAX_QUERY_LIMIT,
        after: None,
        all: true,
        max_pages: DEFAULT_MAX_PAGES,
    };
    let (collections, collection_pages) = collect_keyset_pages(&options, |after, limit| {
        let page = fetch_collection_page(target, after, limit)?;
        Ok((page.collections, page.next_after))
    })?;
    let (pokemon_sets, set_pages) = collect_keyset_pages(&options, |after, limit| {
        let page = fetch_set_page(target, after, limit)?;
        Ok((page.sets, page.next_after))
    })?;
    let (pokemon_cards, card_pages) = collect_keyset_pages(&options, |after, limit| {
        let page = fetch_card_page(target, after, limit)?;
        Ok((page.cards, page.next_after))
    })?;
    let backup = CanonicalBackup {
        format_version: CANONICAL_BACKUP_FORMAT_VERSION,
        collections,
        pokemon_sets,
        pokemon_cards,
    };
    write_backup(path, &backup)?;
    Ok(json!({
        "path": path,
        "format_version": CANONICAL_BACKUP_FORMAT_VERSION,
        "collections": backup.collections.len(),
        "pokemon_sets": backup.pokemon_sets.len(),
        "pokemon_cards": backup.pokemon_cards.len(),
        "pages": collection_pages.saturating_add(set_pages).saturating_add(card_pages),
    }))
}

fn write_backup(path: &Path, backup: &CanonicalBackup) -> Result<(), CliError> {
    let parent = path
        .parent()
        .filter(|parent| !parent.as_os_str().is_empty());
    if let Some(parent) = parent {
        fs::create_dir_all(parent).map_err(|source| CliError::BackupIo {
            action: "create parent for",
            path: path.to_owned(),
            source,
        })?;
    }
    let file_name = path
        .file_name()
        .and_then(|name| name.to_str())
        .ok_or_else(|| {
            CliError::Usage("canonical backup path must name a UTF-8 JSON file".to_owned())
        })?;
    let temporary = path.with_file_name(format!(".{file_name}.{}.tmp", std::process::id()));
    let mut bytes = serde_json::to_vec_pretty(backup)?;
    bytes.push(b'\n');
    fs::write(&temporary, bytes).map_err(|source| CliError::BackupIo {
        action: "write",
        path: temporary.clone(),
        source,
    })?;
    if let Err(source) = fs::rename(&temporary, path) {
        let _ = fs::remove_file(&temporary);
        return Err(CliError::BackupIo {
            action: "replace",
            path: path.to_owned(),
            source,
        });
    }
    Ok(())
}