//! Executor-context policy operations that never consult controller paths or environment.

use super::FileSystemPath;
use super::FileSystemSandboxPolicy;
use super::FileSystemSandboxPolicyContext;
use super::FileSystemSpecialPath;
use super::InvalidDenyReadGlobBehavior;
use super::ReadDenyMatcher;
use super::deny_read_validator::DenyReadValidator;
use super::deny_read_validator::has_context_read_denials;
use codex_utils_path_uri::PathConvention;
use codex_utils_path_uri::PathUri;

const INVALID_PATH: &str = "managed filesystem denial cannot be materialized safely";
const SHADOWED: &str = "managed filesystem denial is shadowed by a selected profile grant";

impl ReadDenyMatcher {
    /// Builds a strict matcher using only the supplied execution-host paths.
    pub fn try_new_with_context(
        policy: &FileSystemSandboxPolicy,
        context: &FileSystemSandboxPolicyContext<'_>,
    ) -> Result<Option<Self>, String> {
        if !has_context_read_denials(policy, context) {
            return Ok(None);
        }
        validate_context_paths(policy, context)?;
        let prepared =
            policy.prepare_deny_read_matcher(context, InvalidDenyReadGlobBehavior::ReturnError)?;
        Ok(Some(Self {
            native_cwd: None,
            user_home_dir: None,
            temporary_directories: Vec::new(),
            prepared,
        }))
    }
}

impl FileSystemSandboxPolicy {
    /// Checks exact-root read access using paths owned by the execution host.
    /// Deny glob enforcement is checked separately with [`ReadDenyMatcher`].
    pub fn can_read_path(
        &self,
        path: &PathUri,
        context: &FileSystemSandboxPolicyContext<'_>,
    ) -> bool {
        self.resolve_access(path, context).can_read()
    }

    /// Preserves workspace-root symbols and adds their executor-owned concrete paths.
    /// Legacy home-relative workspace denials clear all grants when their target is unknown.
    pub fn with_materialized_project_roots_for_path_uris(mut self, roots: &[PathUri]) -> Self {
        let Some(materialized) = self
            .clone()
            .try_materialize_project_roots_with_path_uris(roots)
        else {
            return Self::restricted(Vec::new());
        };
        for entry in materialized.entries {
            if !self.entries.contains(&entry) {
                self.entries.push(entry);
            }
        }
        self
    }

    /// Builds workspace-write defaults without inspecting the execution host's filesystem.
    pub fn workspace_write_with_path_uris(
        roots: &[PathUri],
        exclude_tmpdir_env_var: bool,
        exclude_slash_tmp: bool,
    ) -> Self {
        Self::workspace_write(&[], exclude_tmpdir_env_var, exclude_slash_tmp)
            .with_materialized_project_roots_for_path_uris(roots)
    }

    /// Resolves deny glob text using the execution host's convention and home.
    pub fn get_unreadable_globs_with_context(
        &self,
        context: &FileSystemSandboxPolicyContext<'_>,
    ) -> Result<Vec<String>, String> {
        self.deny_read_globs(context)
    }

    /// Checks the existing Core rules for required entries and readable concrete paths.
    ///
    /// Sandbox-mode selection and native glob expansion remain caller-owned.
    pub fn validate_managed_deny_read(
        &self,
        required: &Self,
        context: &FileSystemSandboxPolicyContext<'_>,
    ) -> Result<(), String> {
        DenyReadValidator::new(required, context)?
            .validate(self, context)
            .map_err(|_| SHADOWED.to_string())
    }
}

fn validate_context_paths(
    policy: &FileSystemSandboxPolicy,
    context: &FileSystemSandboxPolicyContext<'_>,
) -> Result<(), String> {
    let convention = context.cwd.infer_path_convention().ok_or(INVALID_PATH)?;
    let valid = |path: &PathUri| {
        path.infer_path_convention() == Some(convention) && path.lexical_depth().is_some()
    };
    if !valid(context.cwd) || context.workspace_roots.iter().any(|path| !valid(path)) {
        return Err(INVALID_PATH.into());
    }
    for entry in &policy.entries {
        match &entry.path {
            FileSystemPath::Path { path } if !valid(path) => return Err(INVALID_PATH.into()),
            FileSystemPath::Special {
                value: FileSystemSpecialPath::Tmpdir,
            } => {
                let directories = context.temporary_directories.ok_or(
                    "executor temporary-directory metadata is unavailable for managed filesystem denials",
                )?;
                if directories.iter().any(|path| !valid(path)) {
                    return Err(
                        "executor temporary-directory metadata cannot be materialized safely"
                            .into(),
                    );
                }
            }
            FileSystemPath::Special {
                value:
                    FileSystemSpecialPath::ProjectRoots {
                        subpath: Some(subpath),
                    },
            } if context
                .workspace_roots
                .iter()
                .any(|root| root.join(subpath).is_err()) =>
            {
                return Err(INVALID_PATH.into());
            }
            FileSystemPath::GlobPattern { pattern }
                if (pattern.starts_with("~/")
                    || convention == PathConvention::Windows && pattern.starts_with("~\\"))
                    && !context.user_home_dir.is_some_and(valid) =>
            {
                return Err(INVALID_PATH.into());
            }
            _ => {}
        }
    }
    Ok(())
}

#[cfg(test)]
#[path = "target_tests.rs"]
mod tests;