use kxio::network;
use terrors::OneOf;
use tracing::error;

use crate::server::{
    config::{BranchName, RepoConfig, RepoDetails},
    gitforge::{self, ForgeFileError},
};

#[derive(Debug)]
pub struct RepoConfigFileNotFound;
#[derive(Debug)]
pub struct RepoConfigIsNotFile;
#[derive(Debug)]
pub struct RepoConfigDecodeError;
#[derive(Debug)]
pub struct RepoConfigParseError;
#[derive(Debug)]
pub struct RepoConfigUnknownError(pub network::StatusCode);

pub async fn load(
    details: &RepoDetails,
    forge: &gitforge::Forge,
) -> Result<RepoConfig, OneOf<(ForgeFileError, toml::de::Error, RepoConfigValidationErrors)>> {
    let contents = forge
        .file_contents_get(&details.branch, ".git-next.toml")
        .await
        .map_err(OneOf::new)?;
    let config = RepoConfig::load(&contents).map_err(OneOf::new)?;
    let config = validate(config, forge).await.map_err(OneOf::new)?;
    Ok(config)
}

#[derive(Debug)]
pub enum RepoConfigValidationErrors {
    Forge(gitforge::ForgeBranchError),
    BranchNotFound(BranchName),
}

pub async fn validate(
    config: RepoConfig,
    forge: &gitforge::Forge,
) -> Result<RepoConfig, RepoConfigValidationErrors> {
    let branches = forge.branches_get_all().await.map_err(|e| {
        error!(?e, "Failed to list branches");
        RepoConfigValidationErrors::Forge(e)
    })?;
    if !branches
        .iter()
        .any(|branch| branch.name() == &config.branches().main())
    {
        return Err(RepoConfigValidationErrors::BranchNotFound(
            config.branches().main(),
        ));
    }
    if !branches
        .iter()
        .any(|branch| branch.name() == &config.branches().next())
    {
        return Err(RepoConfigValidationErrors::BranchNotFound(
            config.branches().next(),
        ));
    }
    if !branches
        .iter()
        .any(|branch| branch.name() == &config.branches().dev())
    {
        return Err(RepoConfigValidationErrors::BranchNotFound(
            config.branches().dev(),
        ));
    }
    Ok(config)
}