use git2::{Cred, RemoteCallbacks};
use itertools::Itertools;
use near_client::{
    client::{NearClient, Signer},
    types::{
        crypto::{ED25519PublicKey, ED25519SecretKey, Key},
        near::{ViewAccessKey, ViewAccessKeyResult},
    },
};
use rand::{RngCore, SeedableRng};
use rand_chacha::ChaChaRng;
use reqwest::Url;
use serde_json::json;
use std::{
    fs::{create_dir, read, write},
    path::Path,
    str::FromStr,
};
use workspaces::{network::Sandbox, types::SecretKey, AccountId, Worker};

// auxiliary structs and methods
fn near_client(worker: &Worker<Sandbox>) -> anyhow::Result<NearClient> {
    let rpc_url = Url::parse(format!("http://localhost:{}", worker.rpc_port()).as_str())?;
    let client = NearClient::new(rpc_url)?;
    Ok(client)
}

async fn create_signer(
    worker: &Worker<Sandbox>,
    client: &NearClient,
    signer_acc_id: &AccountId,
) -> anyhow::Result<Signer> {
    let secret_key = ED25519SecretKey::from_bytes(&random_bits())?;
    let ws_secret_key_str = to_workspaces_sk(&secret_key);
    let pk = ED25519PublicKey::from(&secret_key);
    let ws_sk = SecretKey::from_str(&ws_secret_key_str)?;
    let _ = worker.create_tla(signer_acc_id.clone(), ws_sk).await?;

    client
        .view_access_key(signer_acc_id, &pk)
        .await
        .map(|access_key_view| match access_key_view.result {
            ViewAccessKeyResult::Ok { nonce, .. } => {
                let signer_acc = Signer::new(&ws_secret_key_str, signer_acc_id.clone(), nonce)?;
                Ok(signer_acc)
            }
            ViewAccessKeyResult::Err { error, .. } => Err(anyhow::anyhow!(error)),
        })?
}

async fn download_contract() -> anyhow::Result<Vec<u8>> {
    let target = "https://github.com/near-examples/FT/raw/master/res/fungible_token.wasm";
    let target_path = "../target/tmp-contracts";
    let fname = "contract.wasm";
    let full_dest = format!("{}/{}", target_path, fname);

    let contract_bytes = if !Path::new(&full_dest).exists() {
        if !Path::new(&target_path).exists() {
            create_dir(target_path)?;
        };

        let contract_bytes = reqwest::get(target).await?.bytes().await?;
        write(full_dest, &contract_bytes)?;
        contract_bytes.to_vec()
    } else {
        read(&full_dest)?
    };

    Ok(contract_bytes)
}

async fn clone_and_compile_wasm() -> anyhow::Result<Vec<u8>> {
    let tmp_path = "../target/tmp-contracts";
    let repo_path = format!("{}/near-smartcontracts", tmp_path);
    let target_path = format!("{}/test-contract", repo_path);
    let repo_url = "git@github.com:Relayz-io/near-smartcontracts.git";

    if !Path::new(&target_path).exists() {
        if !Path::new(&tmp_path).exists() {
            create_dir(tmp_path)?;
        }

        // Prepare callbacks.
        let mut callbacks = RemoteCallbacks::new();
        callbacks.credentials(|_, username_from_url, _| {
            let username = username_from_url
                .ok_or_else(|| git2::Error::from_str("Parsing the given URL is failed"))?;
            Cred::ssh_key_from_agent(username)
        });

        // Prepare fetch options.
        let mut fo = git2::FetchOptions::new();
        fo.remote_callbacks(callbacks);

        // Prepare builder.
        let mut builder = git2::build::RepoBuilder::new();
        builder.fetch_options(fo);
        builder.branch("main");

        // Clone the project.
        builder.clone(repo_url, Path::new(&repo_path))?;
    }
    let wasm = workspaces::compile_project(&target_path).await?;

    Ok(wasm)
}

fn random_bits() -> [u8; 32] {
    let mut chacha = ChaChaRng::from_entropy();
    let mut secret_bytes = [0_u8; 32];
    chacha.fill_bytes(&mut secret_bytes);
    secret_bytes
}

fn to_workspaces_sk(sk: &ED25519SecretKey) -> String {
    let pk = ED25519PublicKey::from(sk);
    let keypair = sk
        .as_bytes()
        .iter()
        .chain(pk.as_bytes().iter())
        .copied()
        .collect_vec();
    format!("ed25519:{}", bs58::encode(keypair).into_string())
}

// tests themselves
#[tokio::test]
async fn contract_creation() -> anyhow::Result<()> {
    let worker = workspaces::sandbox().await?;
    let client = near_client(&worker)?;
    let signer_account_id = AccountId::from_str("alice.test.near").unwrap();
    let mut signer = create_signer(&worker, &client, &signer_account_id).await?;
    let wasm = download_contract().await?;

    client
        .deploy_contract(&mut signer, &signer_account_id, wasm)
        .commit_empty()
        .await?;

    Ok(())
}

#[tokio::test]
async fn contract_function_call() -> anyhow::Result<()> {
    let worker = workspaces::sandbox().await?;
    let client = near_client(&worker)?;
    let signer_account_id = AccountId::from_str("alice.test.near").unwrap();
    let mut signer = create_signer(&worker, &client, &signer_account_id).await?;
    let wasm = download_contract().await?;

    client
        .deploy_contract(&mut signer, &signer_account_id, wasm)
        .commit_empty()
        .await?;

    client
        .function_call(&mut signer, &signer_account_id, "new_default_meta")
        .args(json!({
            "owner_id": &signer_account_id,
            "total_supply": "100",
        }))
        .gas(near_units::parse_gas!("300 T") as u64)
        .build()?
        .commit_empty()
        .await?;

    Ok(())
}

#[tokio::test]
async fn multiple_tests() -> anyhow::Result<()> {
    let worker = workspaces::sandbox().await?;
    let client = near_client(&worker)?;
    let signer_account_id = AccountId::from_str("alice.test.near").unwrap();
    let mut signer = create_signer(&worker, &client, &signer_account_id).await?;

    let wasm = clone_and_compile_wasm().await?;

    init_contract(&client, &signer_account_id, &mut signer, wasm).await?;

    fc_no_params(&client, &signer_account_id, &mut signer).await?;
    fc_with_one_param_and_result(&client, &signer_account_id, &mut signer).await?;
    fc_with_param_and_result(&client, &signer_account_id, &mut signer).await?;

    view_no_params(&client, &signer_account_id).await?;
    view_with_params(&client, &signer_account_id).await?;

    Ok(())
}

async fn init_contract(
    client: &NearClient,
    contract_id: &AccountId,
    signer: &mut Signer,
    wasm: Vec<u8>,
) -> anyhow::Result<()> {
    client
        .deploy_contract(signer, contract_id, wasm)
        .commit_empty()
        .await?;

    Ok(())
}

async fn view_no_params(client: &NearClient, contract_id: &AccountId) -> anyhow::Result<()> {
    client.view::<u64>(contract_id, "show_id", None).await?;

    Ok(())
}

async fn view_with_params(client: &NearClient, contract_id: &AccountId) -> anyhow::Result<()> {
    client
        .view::<String>(contract_id, "show_type", Some(json!({"is_message": true})))
        .await?;

    Ok(())
}

// fc = function call
async fn fc_no_params(
    client: &NearClient,
    contract_id: &AccountId,
    signer: &mut Signer,
) -> anyhow::Result<()> {
    client
        .function_call(signer, contract_id, "increment")
        .gas(near_units::parse_gas!("300 T") as u64)
        .build()?
        .commit_empty()
        .await?;

    Ok(())
}

async fn fc_with_one_param_and_result(
    client: &NearClient,
    contract_id: &AccountId,
    signer: &mut Signer,
) -> anyhow::Result<()> {
    let expected_result = "change message";
    let message = client
        .function_call(signer, contract_id, "change_message")
        .args(json!({ "message": expected_result }))
        .gas(near_units::parse_gas!("300 T") as u64)
        .build()?
        .commit::<String>()
        .await?;

    assert_eq!(message, expected_result);

    Ok(())
}

async fn fc_with_param_and_result(
    client: &NearClient,
    contract_id: &AccountId,
    signer: &mut Signer,
) -> anyhow::Result<()> {
    let expected_id = 666u64;
    let id = client
        .function_call(signer, contract_id, "change_id")
        .args(json!({ "id": expected_id }))
        .gas(near_units::parse_gas!("300 T") as u64)
        .build()?
        .commit::<u64>()
        .await?;

    assert_eq!(id, expected_id);

    Ok(())
}

#[tokio::test]
async fn view_access_key_success() -> anyhow::Result<()> {
    let worker = workspaces::sandbox().await?;
    let client = near_client(&worker)?;
    let signer_account_id = AccountId::from_str("alice.test.near").unwrap();
    let mut signer = create_signer(&worker, &client, &signer_account_id).await?;

    let new_acc = AccountId::from_str("one.alice.test.near")?;
    let secret_key = ED25519SecretKey::from_bytes(&random_bits())?;
    let pk = ED25519PublicKey::from(&secret_key);

    let _ = client
        .create_account(&mut signer, &new_acc, pk, near_units::parse_near!("3 N"))
        .commit::<serde_json::Value>()
        .await?;

    let access_key = client.view_access_key(&new_acc, &pk).await?;
    assert!(matches!(
        access_key,
        ViewAccessKey {
            result: ViewAccessKeyResult::Ok { .. },
            ..
        }
    ));

    Ok(())
}

#[tokio::test]
async fn view_access_key_failure() -> anyhow::Result<()> {
    let worker = workspaces::sandbox().await?;
    let client = near_client(&worker)?;

    let new_acc = AccountId::from_str("one.alice.test.near")?;
    let secret_key = ED25519SecretKey::from_bytes(&random_bits())?;
    let pk = ED25519PublicKey::from(&secret_key);

    let access_key = client.view_access_key(&new_acc, &pk).await?;
    assert!(matches!(
        access_key,
        ViewAccessKey {
            result: ViewAccessKeyResult::Err { .. },
            ..
        }
    ));

    Ok(())
}

#[tokio::test]
async fn create_account() -> anyhow::Result<()> {
    let worker = workspaces::sandbox().await?;
    let client = near_client(&worker)?;
    let signer_account_id = AccountId::from_str("alice.test.near").unwrap();
    let mut signer = create_signer(&worker, &client, &signer_account_id).await?;

    let new_acc = AccountId::from_str("one.alice.test.near")?;
    let secret_key = ED25519SecretKey::from_bytes(&random_bits())?;
    let pk = ED25519PublicKey::from(&secret_key);

    let _ = client
        .create_account(&mut signer, &new_acc, pk, near_units::parse_near!("3 N"))
        .commit::<serde_json::Value>()
        .await?;

    let access_key = client.view_access_key(&new_acc, &pk).await?;
    assert!(matches!(
        access_key,
        ViewAccessKey {
            result: ViewAccessKeyResult::Ok { .. },
            ..
        }
    ));

    Ok(())
}

#[tokio::test]
async fn delete_account() -> anyhow::Result<()> {
    let worker = workspaces::sandbox().await?;
    let client = near_client(&worker)?;
    let signer_account_id = AccountId::from_str("alice.test.near").unwrap();
    let mut signer = create_signer(&worker, &client, &signer_account_id).await?;

    let new_acc = AccountId::from_str("one.alice.test.near")?;
    let secret_key = ED25519SecretKey::from_bytes(&random_bits())?;
    let pk = ED25519PublicKey::from(&secret_key);

    client
        .create_account(&mut signer, &new_acc, pk, near_units::parse_near!("3 N"))
        .commit_empty()
        .await?;

    let access_key = client.view_access_key(&new_acc, &pk).await?;

    let nonce = if let ViewAccessKey {
        result: ViewAccessKeyResult::Ok { nonce, .. },
        ..
    } = access_key
    {
        nonce
    } else {
        panic!("Can't view access key for just created account")
    };

    let mut acc_signer = Signer::new(&secret_key.to_string(), new_acc.clone(), nonce)?;
    client
        .delete_account(&mut acc_signer, &new_acc, &signer_account_id)
        .commit_empty()
        .await?;

    let access_key = client.view_access_key(&new_acc, &pk).await?;
    assert!(matches!(
        access_key,
        ViewAccessKey {
            result: ViewAccessKeyResult::Err { .. },
            ..
        }
    ));

    Ok(())
}