//! Database repositories for feeds, items, and busser state.
//!
//! Each repository wraps an SQLite connection pool and provides typed
//! CRUD operations for a single table.

use chrono::{DateTime, Utc};
use sqlx::SqlitePool;

use bb_interface::{ErrorCategory, StructuredError};

use crate::TIMESTAMP_FMT;
use crate::id_types::{BookmarkId, BusserStateId, FeedId, ItemId, QueryFeedId};
use crate::models::{
    CreateBookmark, CreateFeed, CreateFeedItem, CreateQueryFeed, DbBookmark, DbBusserState, DbFeed,
    DbFeedItem, DbQueryFeed, QueryCondition, UpdateBookmark,
};

/// Sanitize a user-provided search string for FTS5 MATCH syntax.
///
/// Wraps each word in double quotes to prevent FTS5 syntax injection
/// (e.g. a user typing `AND`, `OR`, `NOT`, `NEAR`, or `NEAR/N` won't be
/// interpreted as FTS5 operators). Words are joined with spaces (implicit AND).
///
/// Inside quoted strings FTS5 still honours two special characters:
///   - `*` at the end of the last token triggers prefix matching
///   - `^` at the start of the first token triggers beginning-of-column matching
///
/// We strip those so user input like `^hello` or `world*` is treated literally.
/// The `column:` prefix syntax (e.g. `title:word`) is neutralised by the quoting
/// itself, colons inside double-quoted strings are treated as literal characters.
fn sanitize_fts_query(query: &str) -> String {
    query
        .split_whitespace()
        .map(|word| {
            // Escape embedded double quotes (FTS5 uses "" to represent a literal ")
            let escaped = word.replace('"', "\"\"");
            // Strip `^` prefix and `*` suffix, both are special inside FTS5 quotes
            let escaped = escaped.trim_start_matches('^');
            let escaped = escaped.trim_end_matches('*');
            format!("\"{escaped}\"")
        })
        // Drop tokens that became empty after stripping (e.g. bare `^`, `*`, `^*`)
        .filter(|token| token != "\"\"")
        .collect::<Vec<_>>()
        .join(" ")
}

/// Maximum allowed length for a search query string.
///
/// Queries longer than this are rejected early (returning an empty result set)
/// to prevent excessively large FTS5 MATCH expressions from consuming memory
/// or CPU in SQLite.
const MAX_SEARCH_QUERY_LENGTH: usize = 500;

/// Number of consecutive failures before a feed is automatically disabled.
///
/// Once a feed accumulates this many failures without a successful fetch,
/// the circuit breaker trips: the feed is marked `circuit_broken = 1` and
/// excluded from automatic fetch scheduling until manually reset.
pub const CIRCUIT_BREAKER_THRESHOLD: i64 = 10;

mod bookmarks;
mod config;
mod feeds;
mod items;
mod query_feeds;
mod state;
mod tags;

pub use bookmarks::*;
pub use config::*;
pub use feeds::*;
pub use items::*;
pub use query_feeds::*;
pub use state::*;
pub use tags::*;

#[cfg(test)]
mod tests;