// Copyright (C) 2024-2026 Whiterun LLC
//
// This software is licensed under the GNU Affero General Public License (AGPL), version 3.0 or later.
// A copy of the license can be found in the LICENSE file or at https://www.gnu.org/licenses/agpl-3.0.html

use bitcoin_hashes::hex::{FromHex, ToHex};
use bitcoincash::TokenID;
use rocket::{get, State};
use serde_json::json;
use serde_json::Value;

use crate::db::cauldron::tokenlist::db_utils::{
    cache_first_pool_ts_if_empty, db_first_pool_creation_row, CachedSort,
};
use crate::db::cauldron::tokenlist::list_cached::{
    db_list_tokens_cached, db_list_tokens_cached_by_ids, TokenListItemCached,
};
use crate::db::search::db_search_tokens_cached;
use crate::db::DB;

use super::err::{bad_request, db_error, not_found, ApiErrorCode, CachedApiResult};
use super::response::{cached_ok, CACHE_AGGREGATE, CACHE_IMMUTABLE};

/// Search tokens by name or symbol, sorted by trade volume.
///
/// Status: Unstable
///
/// Queries BCMR and CRC20 registries for matching tokens, then joins with live
/// trade volume data.
///
/// - search_query: Token name or symbol to search for
///
/// **Response:** A direct JSON array, sorted by `trade_volume` descending.
///
/// **Response Example:**
/// ```json
/// [
///   {
///     "token_id": "b79bfc8246b5fc4707e7c7dedcb6619ef1ab91f494a790c20b0f4c422ed95b92",
///     "name": "ExampleToken",
///     "ticker": "EXT",
///     "trade_volume": 1459676788
///   }
/// ]
/// ```
#[get("/tokens/search_by_volume?<search_query>")]
pub async fn search_by_volume(search_query: &str, db: &State<DB>) -> CachedApiResult<Vec<Value>> {
    use rayon::prelude::*;

    let list: Vec<(String, Option<String>, Option<String>, u64)> =
        crate::db::search::search_tokens_by_volume(
            &db.cauldron_r,
            &db.bcmr_r,
            &db.crc20_r,
            search_query,
        )
        .await
        .map_err(db_error)?;

    let result: Vec<Value> = list
        .into_par_iter()
        .map(|(token_id, name, ticker, trade_volume)| {
            json!({
                "token_id": token_id,
                "name": name,
                "ticker": ticker,
                "trade_volume": trade_volume
            })
        })
        .collect();
    Ok(cached_ok(result, CACHE_AGGREGATE))
}

/// Search tokens with optional filtering and sorting.
///
/// - q: Search query string
/// - limit: Maximum number of results (default: 250)
/// - offset: Pagination offset (default: 0)
/// - by: Sort field (`name`, `symbol`, `tvl`, `volume`)
/// - order: Sort direction (`asc`, `desc`)
///
/// **Response:** A direct JSON array.
///
/// **Response Example:**
/// ```json
/// [
///   {
///     "token_id": "b79bfc8246b5fc4707e7c7dedcb6619ef1ab91f494a790c20b0f4c422ed95b92",
///     "name": "ExampleToken",
///     "symbol": "EXT",
///     "decimals": 8
///   }
/// ]
/// ```
#[get("/tokens/search_cached?<q>&<limit>&<offset>&<by>&<order>")]
pub async fn search_cached(
    db: &State<DB>,
    q: Option<String>,
    limit: Option<usize>,
    offset: Option<usize>,
    by: Option<String>,
    order: Option<String>,
) -> CachedApiResult<Value> {
    let sort = parse_cached_sort(by, order);
    let limit = limit.unwrap_or(250);
    let offset = offset.unwrap_or(0);
    let query = q.unwrap_or_default();

    let items: Vec<TokenListItemCached> =
        db_search_tokens_cached(&db.cauldron_r, &query, sort, limit, offset)
            .await
            .map_err(db_error)?;

    Ok(cached_ok(json!(items), CACHE_AGGREGATE))
}

fn parse_cached_sort(by: Option<String>, order: Option<String>) -> CachedSort {
    let desc = matches!(order.as_deref(), Some("desc") | Some("DESC"));
    match by.as_deref() {
        Some("name") => {
            if desc {
                CachedSort::NameDesc
            } else {
                CachedSort::NameAsc
            }
        }
        Some("symbol") => {
            if desc {
                CachedSort::SymbolDesc
            } else {
                CachedSort::SymbolAsc
            }
        }
        Some("tvl") => {
            if desc {
                CachedSort::TvlDesc
            } else {
                CachedSort::TvlAsc
            }
        }
        Some("volume") => {
            if desc {
                CachedSort::VolumeDesc
            } else {
                CachedSort::VolumeAsc
            }
        }
        Some("change_24h_bp") => {
            if desc {
                CachedSort::Change24hDesc
            } else {
                CachedSort::Change24hAsc
            }
        }
        Some("change_7d_bp") => {
            if desc {
                CachedSort::Change7dDesc
            } else {
                CachedSort::Change7dAsc
            }
        }

        // USD sorts
        Some("price_usd") => {
            if desc {
                CachedSort::PriceUsdDesc
            } else {
                CachedSort::PriceUsdAsc
            }
        }
        Some("change_24h_usd_bp") => {
            if desc {
                CachedSort::Change24hUsdDesc
            } else {
                CachedSort::Change24hUsdAsc
            }
        }
        Some("change_7d_usd_bp") => {
            if desc {
                CachedSort::Change7dUsdDesc
            } else {
                CachedSort::Change7dUsdAsc
            }
        }

        // APY (30d) sorts — accept a few aliases
        Some("apy") | Some("apy_30d") | Some("apy_30d_bp") => {
            if desc {
                CachedSort::Apy30dDesc
            } else {
                CachedSort::Apy30dAsc
            }
        }

        // default
        _ => {
            if desc {
                CachedSort::ScoreDesc
            } else {
                CachedSort::ScoreAsc
            }
        }
    }
}

/// List all tokens with optional pagination and sorting.
///
/// Similar to `/tokens/search_cached` but without search filtering — returns all tokens
/// sorted by the specified field.
///
/// - limit: Maximum number of results (default: 250)
/// - offset: Pagination offset (default: 0)
/// - by: Sort field (`name`, `symbol`, `tvl`, `volume`, `score`)
/// - order: Sort direction (`asc`, `desc`)
///
/// **Response:** A direct JSON array.
#[get("/tokens/list_cached?<limit>&<offset>&<by>&<order>")]
pub async fn list_cached(
    db: &State<DB>,
    limit: Option<usize>,
    offset: Option<usize>,
    by: Option<String>,
    order: Option<String>,
) -> CachedApiResult<Value> {
    let limit = limit.unwrap_or(250);
    let offset = offset.unwrap_or(0);

    let sort = parse_cached_sort(by, order);
    let items: Vec<TokenListItemCached> =
        db_list_tokens_cached(&db.cauldron_r, limit, offset, sort)
            .await
            .map_err(db_error)?;

    Ok(cached_ok(json!(items), CACHE_AGGREGATE))
}

/// List specific tokens by their IDs.
///
/// Status: Unstable
///
/// Fetch token metadata for multiple tokens in a single request.
///
/// - ids: Comma-separated list of token IDs (hex strings)
/// - by: Sort field for results (`name`, `symbol`, `tvl`, `volume`, `score`)
/// - order: Sort direction (`asc`, `desc`)
///
/// **Response:** A direct JSON array.
///
/// **Example:**
/// `/tokens/list_cached_by_ids?ids=b79bfc8246b5fc4707e7c7dedcb6619ef1ab91f494a790c20b0f4c422ed95b92,abc123...`
#[get("/tokens/list_cached_by_ids?<ids>&<by>&<order>")]
pub async fn list_cached_by_ids(
    db: &State<DB>,
    ids: &str,
    by: Option<String>,
    order: Option<String>,
) -> CachedApiResult<Value> {
    // split, trim, and normalize (lowercase is typical for hex IDs in DB)
    let token_ids: Vec<String> = ids
        .split(',')
        .map(|s| s.trim().to_lowercase())
        .filter(|s| !s.is_empty())
        .collect();

    if token_ids.is_empty() {
        return Ok(cached_ok(json!([]), CACHE_AGGREGATE));
    }

    let sort = parse_cached_sort(by, order);
    let items = db_list_tokens_cached_by_ids(&db.cauldron_r, &token_ids, sort)
        .await
        .map_err(db_error)?;

    Ok(cached_ok(json!(items), CACHE_AGGREGATE))
}

/// Get the first pool creation event for a given token.
///
/// - token: The 32 byte token ID
///
/// Returns 404 if no pools have ever been created for the token.
///
/// **Response Example:**
/// ```json
/// {
///   "token": "b79bfc8246b5fc4707e7c7dedcb6619ef1ab91f494a790c20b0f4c422ed95b92",
///   "creation_utxo": "94a933a0fa55093a0965eb867f1b9cac2bb07488ced4825bc31f86c9371f76aa:0",
///   "txid": "94a933a0fa55093a0965eb867f1b9cac2bb07488ced4825bc31f86c9371f76aa",
///   "timestamp": 1709468902,
///   "block_height": 880000
/// }
/// ```
#[get("/token/<token>/first_pool")]
pub async fn first_pool_creation(token: &str, dbp: &State<DB>) -> CachedApiResult<Value> {
    let token = TokenID::from_hex(token).map_err(|e| {
        bad_request(
            ApiErrorCode::InvalidTokenId,
            &format!("Invalid token id: {e}"),
        )
    })?;
    let token_hex = token.to_hex();

    match db_first_pool_creation_row(&dbp.cauldron_r, &token_hex).await {
        Ok(Some((creation_utxo, txid, timestamp, block_height))) => {
            // Opportunistically cache the timestamp (non-blocking)
            let cauldron_w = dbp.cauldron_w.clone();
            let token_hex_clone = token_hex.clone();
            tokio::spawn(async move {
                if let Err(e) =
                    cache_first_pool_ts_if_empty(&cauldron_w, &token_hex_clone, timestamp).await
                {
                    log::warn!("Failed to cache first_pool_ts for {token_hex_clone}: {e}");
                }
            });

            Ok(cached_ok(
                json!({
                    "token": token_hex,
                    "creation_utxo": creation_utxo,
                    "txid": txid,
                    "timestamp": timestamp,
                    "block_height": block_height
                }),
                CACHE_IMMUTABLE,
            ))
        }
        Ok(None) => Err(not_found(ApiErrorCode::PoolNotFound, "No pools for token")),
        Err(e) => Err(db_error(e)),
    }
}