tidploy 0.16.0

use std::{env, fmt::Debug, ops::ControlFlow};

use camino::{Utf8Path, Utf8PathBuf};
use relative_path::{RelativePath, RelativePathBuf};
use tracing::{debug, instrument};

use crate::{
    filesystem::WrapToPath,
    next::config::{get_component_paths, merge_option},
};

use super::{
    config::{
        load_dploy_config, merge_vars, traverse_arg_configs, ArgumentConfig, Config, ConfigScope,
        ConfigVar,
    },
    errors::{ConfigError, ResolutionError, StateError, WrapStateErr},
    state::ResolveState,
};

#[derive(Default)]
pub(crate) struct SecretScopeArguments {
    pub(crate) name: Option<String>,
    pub(crate) sub: Option<String>,
    pub(crate) service: Option<String>,
    pub(crate) require_hash: Option<bool>,
}

impl Mergeable for SecretScopeArguments {
    fn merge(self, other: Self) -> Self {
        Self {
            service: other.service.or(self.service),
            sub: other.sub.or(self.sub),
            name: other.name.or(self.name),
            require_hash: other.require_hash.or(self.require_hash),
        }
    }
}

impl From<ConfigScope> for SecretScopeArguments {
    fn from(value: ConfigScope) -> Self {
        Self {
            service: value.service,
            name: value.name,
            sub: value.sub,
            require_hash: value.require_hash,
        }
    }
}

pub(crate) trait Mergeable {
    fn merge(self, other: Self) -> Self;
}

impl<T: Mergeable> Mergeable for Option<T> {
    fn merge(self, other: Self) -> Self {
        let run_merge = |a: T, b: T| -> T { a.merge(b) };

        merge_option(self, other, &run_merge)
    }
}

pub(crate) trait Resolved<U> {
    fn resolve(self, resolve_root: &Utf8Path) -> U;
}

pub(crate) trait Resolvable<T> {
    fn resolve_from(value: T, resolve_root: &Utf8Path) -> Self;
}

impl<T, U: Resolvable<T>> Resolved<U> for T {
    fn resolve(self, resolve_root: &Utf8Path) -> U {
        U::resolve_from(self, resolve_root)
    }
}

impl Resolvable<String> for Utf8PathBuf {
    fn resolve_from(value: String, resolve_root: &Utf8Path) -> Utf8PathBuf {
        let p = RelativePathBuf::from(value);
        p.to_utf8_path(resolve_root)
    }
}

impl Resolvable<Config> for Option<RunArguments> {
    fn resolve_from(value: Config, resolve_root: &Utf8Path) -> Option<RunArguments> {
        value
            .argument
            .map(|c| RunArguments::from_config(c, resolve_root))
    }
}

impl Resolvable<Config> for Option<SecretScopeArguments> {
    fn resolve_from(value: Config, _resolve_root: &Utf8Path) -> Option<SecretScopeArguments> {
        value
            .argument
            .and_then(|c| c.scope.map(SecretScopeArguments::from))
    }
}

impl<T, U: Resolvable<T>> Resolvable<Option<T>> for Option<U> {
    fn resolve_from(value: Option<T>, resolve_root: &Utf8Path) -> Option<U> {
        value.map(|t| t.resolve(resolve_root))
    }
}

#[derive(Default)]
pub(crate) struct RunArguments {
    pub(crate) executable: Option<Utf8PathBuf>,
    pub(crate) execution_path: Option<Utf8PathBuf>,
    pub(crate) envs: Vec<ConfigVar>,
    pub(crate) scope_args: SecretScopeArguments,
}

impl Mergeable for RunArguments {
    /// Overrides fields with other if other has them defined
    fn merge(self, other: Self) -> Self {
        Self {
            executable: other.executable.or(self.executable),
            execution_path: other.execution_path.or(self.execution_path),
            envs: merge_vars(self.envs, other.envs),
            scope_args: self.scope_args.merge(other.scope_args),
        }
    }
}

impl RunArguments {
    fn from_config(value: ArgumentConfig, resolve_root: &Utf8Path) -> Self {
        RunArguments {
            executable: value.executable.resolve(resolve_root),
            execution_path: value.execution_path.resolve(resolve_root),
            envs: value.envs.unwrap_or_default(),
            scope_args: value.scope.map(|s| s.into()).unwrap_or_default(),
        }
    }
}

pub(crate) struct SecretArguments {
    pub(crate) key: String,
    pub(crate) scope_args: SecretScopeArguments,
}

#[derive(Debug)]
pub(crate) struct SecretScope {
    pub(crate) service: String,
    pub(crate) name: String,
    pub(crate) sub: String,
    pub(crate) hash: String,
}

#[derive(Debug)]
pub(crate) struct RunResolved {
    pub(crate) executable: Utf8PathBuf,
    pub(crate) execution_path: Utf8PathBuf,
    pub(crate) envs: Vec<ConfigVar>,
    pub(crate) scope: SecretScope,
}

#[derive(Debug)]
pub(crate) struct SecretResolved {
    pub(crate) key: String,
    pub(crate) scope: SecretScope,
}

fn env_scope_args() -> SecretScopeArguments {
    let mut scope_args = SecretScopeArguments::default();

    for (k, v) in env::vars() {
        match k.as_str() {
            "TIDPLOY_SECRET_SCOPE_NAME" => scope_args.name = Some(v),
            "TIDPLOY_SECRET_SCOPE_SUB" => scope_args.sub = Some(v),
            "TIDPLOY_SECRET_SERVICE" => scope_args.service = Some(v),
            "TIDPLOY_SECRET_REQUIRE_HASH" => scope_args.require_hash = Some(!v.is_empty()),
            _ => {}
        }
    }

    scope_args
}

/// Note that `key` cannot be set from env and must thus always be replaced with some sensible value.
fn env_secret_args() -> SecretArguments {
    SecretArguments {
        key: "".to_owned(),
        scope_args: env_scope_args(),
    }
}

/// Note that `envs` cannot be set from env and must thus always be replaced with some sensible value.
fn env_run_args(resolve_root: &Utf8Path) -> RunArguments {
    let scope_args = env_scope_args();
    let mut run_arguments = RunArguments {
        scope_args,
        ..Default::default()
    };

    for (k, v) in env::vars() {
        match k.as_str() {
            "TIDPLOY_RUN_EXECUTABLE" => run_arguments.executable = Some(v.resolve(resolve_root)),
            "TIDPLOY_RUN_EXECUTION_PATH" => {
                run_arguments.execution_path = Some(v.resolve(resolve_root))
            }
            _ => {}
        }
    }

    run_arguments
}

pub(crate) trait Resolve<Resolved>: Sized {
    fn merge_env_config(
        self,
        resolve_root: &Utf8Path,
        state_path: &RelativePath,
    ) -> Result<Self, ResolutionError>;

    fn resolve(self, resolve_root: &Utf8Path, name: &str, sub: &str, hash: &str) -> Resolved;
}

fn resolve_scope(
    scope_args: SecretScopeArguments,
    name: &str,
    sub: &str,
    hash: &str,
) -> SecretScope {
    SecretScope {
        service: scope_args.service.unwrap_or("tidploy".to_owned()),
        name: scope_args.name.unwrap_or(name.to_owned()),
        sub: scope_args.sub.unwrap_or(sub.to_owned()),
        hash: if scope_args.require_hash.unwrap_or(false) {
            hash.to_owned()
        } else {
            "tidploy_default_hash".to_owned()
        },
    }
}

// impl Resolve<RunResolved> for RunArguments {
//     fn merge_env_config(
//         self,
//         resolve_root: &Utf8Path,
//         state_path: &RelativePath,
//     ) -> Result<Self, ResolutionError> {
//         let config = traverse_arg_configs(resolve_root, state_path)?;

//         let run_args_env = env_run_args();

//         let merged_args = run_args_env.merge(self);

//         let config_run = config.map(RunArguments::from).unwrap_or_default();

//         Ok(config_run.merge(merged_args))
//     }

//     fn resolve(self, resolve_root: &Utf8Path, name: &str, sub: &str, hash: &str) -> RunResolved {
//         let scope = resolve_scope(self.scope_args, name, sub, hash);

//         let relative_exe = RelativePathBuf::from(self.executable.unwrap_or("entrypoint.sh".to_owned()));
//         let relative_exn_path = RelativePathBuf::from(self.execution_path.unwrap_or("".to_owned()));
//         RunResolved {
//             executable: relative_exe.to_utf8_path(resolve_root),
//             execution_path: relative_exn_path.to_utf8_path(resolve_root),
//             envs: self.envs,
//             scope,
//         }
//     }
// }

pub(crate) fn resolve_run(
    resolve_state: ResolveState,
    cli_args: RunArguments,
) -> Result<RunResolved, StateError> {
    let run_args_env = env_run_args(&resolve_state.resolve_root);
    let merged_args = run_args_env.merge(cli_args);

    let config_args: Option<RunArguments> =
        traverse_args(&resolve_state.resolve_root, &resolve_state.state_path)
            .to_state_err("Failed to traverse config.")?;

    let final_args = config_args.unwrap_or_default().merge(merged_args);

    let scope = resolve_scope(
        final_args.scope_args,
        &resolve_state.name,
        &resolve_state.sub,
        &resolve_state.hash,
    );

    let execution_path = final_args
        .execution_path
        .unwrap_or_else(|| resolve_state.resolve_root.clone());

    let resolved = RunResolved {
        executable: final_args
            .executable
            .unwrap_or_else(|| execution_path.join("entrypoint.sh")),
        execution_path,
        envs: final_args.envs,
        scope,
    };

    Ok(resolved)
}

pub(crate) fn traverse_args<U: Resolvable<Config> + Mergeable>(
    start_path: &Utf8Path,
    final_path: &RelativePath,
) -> Result<U, ConfigError> {
    debug!(
        "Traversing configs from {:?} to relative {:?}",
        start_path, final_path
    );

    let root_config = load_dploy_config(start_path)?;
    let root_args = U::resolve_from(root_config, start_path);

    let paths = get_component_paths(start_path, final_path);

    let combined_config = paths.iter().try_fold(root_args, |state, path| {
        let inner_config = load_dploy_config(path).map(|c| U::resolve_from(c, path));

        match inner_config {
            Ok(config) => ControlFlow::Continue(state.merge(config)),
            Err(source) => ControlFlow::Break(source),
        }
    });

    match combined_config {
        ControlFlow::Break(e) => Err(e),
        ControlFlow::Continue(config) => Ok(config),
    }
}

impl Resolve<SecretResolved> for SecretArguments {
    fn merge_env_config(
        self,
        resolve_root: &Utf8Path,
        state_path: &RelativePath,
    ) -> Result<Self, ResolutionError> {
        let config = traverse_arg_configs(resolve_root, state_path)?;

        let secret_args_env = env_secret_args();

        let mut merged_args = SecretArguments {
            key: self.key,
            scope_args: secret_args_env.scope_args.merge(self.scope_args),
        };

        let config_scope = config
            .and_then(|a| a.scope)
            .map(SecretScopeArguments::from)
            .unwrap_or_default();

        merged_args.scope_args = config_scope.merge(merged_args.scope_args);

        Ok(merged_args)
    }

    fn resolve(
        self,
        _resolve_root: &Utf8Path,
        name: &str,
        sub: &str,
        hash: &str,
    ) -> SecretResolved {
        let scope = resolve_scope(self.scope_args, name, sub, hash);

        SecretResolved {
            key: self.key,
            scope,
        }
    }
}

/// Loads config, environment variables and resolves the final arguments to make them ready for final use
#[instrument(name = "merge_resolve", level = "debug", skip_all)]
pub(crate) fn merge_and_resolve<T: Debug>(
    unresolved_args: impl Resolve<T>,
    state: ResolveState,
) -> Result<T, ResolutionError> {
    let merged_args = unresolved_args.merge_env_config(&state.resolve_root, &state.state_path)?;

    let resolved = merged_args.resolve(&state.resolve_root, &state.name, &state.sub, &state.hash);
    debug!("Resolved as {:?}", resolved);
    Ok(resolved)
}