use meilisearch_core::settings::{Settings, SettingsUpdate, UpdateState};
use serde::{Deserialize, Serialize};
use std::collections::{BTreeMap, BTreeSet, HashSet};
use tide::{Request, Response};

use crate::error::{ResponseError, SResult};
use crate::helpers::tide::RequestExt;
use crate::models::token::ACL::*;
use crate::routes::document::IndexUpdateResponse;
use crate::Data;

pub async fn get_all(ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsRead)?;
    let index = ctx.index()?;
    let db = &ctx.state().db;
    let reader = db.main_read_txn()?;

    let stop_words_fst = index.main.stop_words_fst(&reader)?;
    let stop_words = stop_words_fst.unwrap_or_default().stream().into_strs()?;
    let stop_words: BTreeSet<String> = stop_words.into_iter().collect();
    let stop_words = if stop_words.is_empty() {
        Some(stop_words)
    } else {
        None
    };

    let synonyms_fst = index.main.synonyms_fst(&reader)?.unwrap_or_default();
    let synonyms_list = synonyms_fst.stream().into_strs()?;

    let mut synonyms = BTreeMap::new();

    let index_synonyms = &index.synonyms;

    for synonym in synonyms_list {
        let alternative_list = index_synonyms.synonyms(&reader, synonym.as_bytes())?;

        if let Some(list) = alternative_list {
            let list = list.stream().into_strs()?;
            synonyms.insert(synonym, list);
        }
    }

    let synonyms = if synonyms.is_empty() {
        Some(synonyms)
    } else {
        None
    };

    let ranking_rules = match index.main.ranking_rules(&reader)? {
        Some(rules) => Some(rules.iter().map(|r| r.to_string()).collect()),
        None => None,
    };
    let ranking_distinct = index.main.ranking_distinct(&reader)?;

    let schema = index.main.schema(&reader)?;

    let identifier = schema.clone().map(|s| s.identifier().to_owned());
    let searchable_attributes = schema
        .clone()
        .map(|s| s.indexed_name().iter().map(|s| s.to_string()).collect());
    let displayed_attributes = schema
        .clone()
        .map(|s| s.displayed_name().iter().map(|s| s.to_string()).collect());
    let index_new_fields = schema.map(|s| s.index_new_fields());

    let settings = Settings {
        ranking_rules: Some(ranking_rules),
        ranking_distinct: Some(ranking_distinct),
        identifier: Some(identifier),
        searchable_attributes: Some(searchable_attributes),
        displayed_attributes: Some(displayed_attributes),
        stop_words: Some(stop_words),
        synonyms: Some(synonyms),
        index_new_fields: Some(index_new_fields),
    };

    Ok(tide::Response::new(200).body_json(&settings).unwrap())
}

#[derive(Default, Clone, Deserialize)]
#[serde(rename_all = "camelCase", deny_unknown_fields)]
pub struct UpdateSettings {
    pub ranking_rules: Option<Vec<String>>,
    pub ranking_distinct: Option<String>,
    pub identifier: Option<String>,
    pub searchable_attributes: Option<Vec<String>>,
    pub displayed_attributes: Option<HashSet<String>>,
    pub stop_words: Option<BTreeSet<String>>,
    pub synonyms: Option<BTreeMap<String, Vec<String>>>,
    pub index_new_fields: Option<bool>,
}

pub async fn update_all(mut ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsWrite)?;
    let index = ctx.index()?;
    let settings_update: UpdateSettings =
        ctx.body_json().await.map_err(ResponseError::bad_request)?;
    let db = &ctx.state().db;

    let settings = Settings {
        ranking_rules: Some(settings_update.ranking_rules),
        ranking_distinct: Some(settings_update.ranking_distinct),
        identifier: Some(settings_update.identifier),
        searchable_attributes: Some(settings_update.searchable_attributes),
        displayed_attributes: Some(settings_update.displayed_attributes),
        stop_words: Some(settings_update.stop_words),
        synonyms: Some(settings_update.synonyms),
        index_new_fields: Some(settings_update.index_new_fields),
    };

    let mut writer = db.update_write_txn()?;
    let update_id = index.settings_update(&mut writer, settings.into_update()?)?;
    writer.commit()?;

    let response_body = IndexUpdateResponse { update_id };
    Ok(tide::Response::new(202).body_json(&response_body)?)
}

pub async fn delete_all(ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsWrite)?;
    let index = ctx.index()?;
    let db = &ctx.state().db;
    let mut writer = db.update_write_txn()?;

    let settings = SettingsUpdate {
        ranking_rules: UpdateState::Clear,
        ranking_distinct: UpdateState::Clear,
        identifier: UpdateState::Clear,
        searchable_attributes: UpdateState::Clear,
        displayed_attributes: UpdateState::Clear,
        stop_words: UpdateState::Clear,
        synonyms: UpdateState::Clear,
        index_new_fields: UpdateState::Clear,
    };

    let update_id = index.settings_update(&mut writer, settings)?;

    writer.commit()?;

    let response_body = IndexUpdateResponse { update_id };
    Ok(tide::Response::new(202).body_json(&response_body)?)
}

pub async fn get_rules(ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsRead)?;
    let index = ctx.index()?;
    let db = &ctx.state().db;
    let reader = db.main_read_txn()?;

    let ranking_rules: Option<Vec<String>> = match index.main.ranking_rules(&reader)? {
        Some(rules) => Some(rules.iter().map(|r| r.to_string()).collect()),
        None => None,
    };

    Ok(tide::Response::new(200).body_json(&ranking_rules).unwrap())
}

pub async fn update_rules(mut ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsWrite)?;
    let index = ctx.index()?;
    let ranking_rules: Option<Vec<String>> =
        ctx.body_json().await.map_err(ResponseError::bad_request)?;
    let db = &ctx.state().db;

    let settings = Settings {
        ranking_rules: Some(ranking_rules),
        ..Settings::default()
    };

    let mut writer = db.update_write_txn()?;
    let update_id = index.settings_update(&mut writer, settings.into_update()?)?;
    writer.commit()?;

    let response_body = IndexUpdateResponse { update_id };
    Ok(tide::Response::new(202).body_json(&response_body)?)
}

pub async fn delete_rules(ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsWrite)?;
    let index = ctx.index()?;
    let db = &ctx.state().db;
    let mut writer = db.update_write_txn()?;

    let settings = SettingsUpdate {
        ranking_rules: UpdateState::Clear,
        ..SettingsUpdate::default()
    };

    let update_id = index.settings_update(&mut writer, settings)?;

    writer.commit()?;

    let response_body = IndexUpdateResponse { update_id };
    Ok(tide::Response::new(202).body_json(&response_body)?)
}

pub async fn get_distinct(ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsRead)?;
    let index = ctx.index()?;
    let db = &ctx.state().db;
    let reader = db.main_read_txn()?;

    let ranking_distinct = index.main.ranking_distinct(&reader)?;

    Ok(tide::Response::new(200)
        .body_json(&ranking_distinct)
        .unwrap())
}

pub async fn update_distinct(mut ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsWrite)?;
    let index = ctx.index()?;
    let ranking_distinct: Option<String> =
        ctx.body_json().await.map_err(ResponseError::bad_request)?;
    let db = &ctx.state().db;

    let settings = Settings {
        ranking_distinct: Some(ranking_distinct),
        ..Settings::default()
    };

    let mut writer = db.update_write_txn()?;
    let update_id = index.settings_update(&mut writer, settings.into_update()?)?;
    writer.commit()?;

    let response_body = IndexUpdateResponse { update_id };
    Ok(tide::Response::new(202).body_json(&response_body)?)
}

pub async fn delete_distinct(ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsWrite)?;
    let index = ctx.index()?;
    let db = &ctx.state().db;
    let mut writer = db.update_write_txn()?;

    let settings = SettingsUpdate {
        ranking_distinct: UpdateState::Clear,
        ..SettingsUpdate::default()
    };

    let update_id = index.settings_update(&mut writer, settings)?;

    writer.commit()?;

    let response_body = IndexUpdateResponse { update_id };
    Ok(tide::Response::new(202).body_json(&response_body)?)
}

pub async fn get_identifier(ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsRead)?;
    let index = ctx.index()?;
    let db = &ctx.state().db;
    let reader = db.main_read_txn()?;

    let schema = index.main.schema(&reader)?;

    let identifier = schema.map(|s| s.identifier().to_string());

    Ok(tide::Response::new(200).body_json(&identifier).unwrap())
}

pub async fn get_searchable(ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsRead)?;
    let index = ctx.index()?;
    let db = &ctx.state().db;
    let reader = db.main_read_txn()?;

    let schema = index.main.schema(&reader)?;

    let searchable_attributes: Option<HashSet<String>> =
        schema.map(|s| s.indexed_name().iter().map(|i| i.to_string()).collect());

    Ok(tide::Response::new(200)
        .body_json(&searchable_attributes)
        .unwrap())
}

pub async fn update_searchable(mut ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsWrite)?;
    let index = ctx.index()?;
    let searchable_attributes: Option<Vec<String>> =
        ctx.body_json().await.map_err(ResponseError::bad_request)?;
    let db = &ctx.state().db;

    let settings = Settings {
        searchable_attributes: Some(searchable_attributes),
        ..Settings::default()
    };

    let mut writer = db.update_write_txn()?;
    let update_id = index.settings_update(&mut writer, settings.into_update()?)?;
    writer.commit()?;

    let response_body = IndexUpdateResponse { update_id };
    Ok(tide::Response::new(202).body_json(&response_body)?)
}

pub async fn delete_searchable(ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsWrite)?;
    let index = ctx.index()?;
    let db = &ctx.state().db;

    let settings = SettingsUpdate {
        searchable_attributes: UpdateState::Clear,
        ..SettingsUpdate::default()
    };

    let mut writer = db.update_write_txn()?;
    let update_id = index.settings_update(&mut writer, settings)?;
    writer.commit()?;

    let response_body = IndexUpdateResponse { update_id };
    Ok(tide::Response::new(202).body_json(&response_body)?)
}

pub async fn displayed(ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsRead)?;
    let index = ctx.index()?;
    let db = &ctx.state().db;
    let reader = db.main_read_txn()?;

    let schema = index.main.schema(&reader)?;

    let displayed_attributes: Option<HashSet<String>> =
        schema.map(|s| s.displayed_name().iter().map(|i| i.to_string()).collect());

    Ok(tide::Response::new(200)
        .body_json(&displayed_attributes)
        .unwrap())
}

pub async fn update_displayed(mut ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsWrite)?;
    let index = ctx.index()?;
    let displayed_attributes: Option<HashSet<String>> =
        ctx.body_json().await.map_err(ResponseError::bad_request)?;
    let db = &ctx.state().db;

    let settings = Settings {
        displayed_attributes: Some(displayed_attributes),
        ..Settings::default()
    };

    let mut writer = db.update_write_txn()?;
    let update_id = index.settings_update(&mut writer, settings.into_update()?)?;
    writer.commit()?;

    let response_body = IndexUpdateResponse { update_id };
    Ok(tide::Response::new(202).body_json(&response_body)?)
}

pub async fn delete_displayed(ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsWrite)?;
    let index = ctx.index()?;
    let db = &ctx.state().db;

    let settings = SettingsUpdate {
        displayed_attributes: UpdateState::Clear,
        ..SettingsUpdate::default()
    };

    let mut writer = db.update_write_txn()?;
    let update_id = index.settings_update(&mut writer, settings)?;
    writer.commit()?;

    let response_body = IndexUpdateResponse { update_id };
    Ok(tide::Response::new(202).body_json(&response_body)?)
}

pub async fn get_index_new_fields(ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsRead)?;
    let index = ctx.index()?;
    let db = &ctx.state().db;
    let reader = db.main_read_txn()?;

    let schema = index.main.schema(&reader)?;

    let index_new_fields = schema.map(|s| s.index_new_fields());

    Ok(tide::Response::new(200)
        .body_json(&index_new_fields)
        .unwrap())
}

pub async fn update_index_new_fields(mut ctx: Request<Data>) -> SResult<Response> {
    ctx.is_allowed(SettingsWrite)?;
    let index = ctx.index()?;
    let index_new_fields: Option<bool> =
        ctx.body_json().await.map_err(ResponseError::bad_request)?;
    let db = &ctx.state().db;

    let settings = Settings {
        index_new_fields: Some(index_new_fields),
        ..Settings::default()
    };

    let mut writer = db.update_write_txn()?;
    let update_id = index.settings_update(&mut writer, settings.into_update()?)?;
    writer.commit()?;

    let response_body = IndexUpdateResponse { update_id };
    Ok(tide::Response::new(202).body_json(&response_body)?)
}