datex_core/runtime/execution/context/

mod.rs

#[cfg(feature = "compiler")]
use crate::compiler::{
    CompileOptions, compile_template, error::SpannedCompilerError,
    scope::CompilationScope,
};
use crate::{
    runtime::execution::{
        ExecutionError, ExecutionInput, MemoryDump, execute_dxb,
        execute_dxb_sync,
    },
    values::value_container::ValueContainer,
};

use crate::prelude::*;
pub use local::*;
use log::info;
pub use remote::*;
pub use script::*;

mod local;
mod remote;
mod script;

/// An execution context holds the persistent state for executing multiple scripts sequentially within the same context.
/// This can be either a local context, which is used for executing scripts in the same process, or a remote context,
/// which is used for executing scripts on a remote endpoint.
#[derive(Debug)]
pub enum ExecutionContext {
    Local(LocalExecutionContext),
    Remote(RemoteExecutionContext),
}

impl ExecutionContext {
    #[cfg(feature = "compiler")]
    fn compile_scope(&self) -> &CompilationScope {
        match self {
            ExecutionContext::Local(LocalExecutionContext {
                compile_scope,
                ..
            }) => compile_scope,
            ExecutionContext::Remote(RemoteExecutionContext {
                compile_scope,
                ..
            }) => compile_scope,
        }
    }

    #[cfg(feature = "compiler")]
    fn set_compile_scope(&mut self, new_compile_scope: CompilationScope) {
        match self {
            ExecutionContext::Local(LocalExecutionContext {
                compile_scope,
                ..
            }) => *compile_scope = new_compile_scope,
            ExecutionContext::Remote(RemoteExecutionContext {
                compile_scope,
                ..
            }) => *compile_scope = new_compile_scope,
        }
    }

    /// Compiles a script using the compile scope of the execution context
    #[cfg(feature = "compiler")]
    pub fn compile(
        &mut self,
        script: &str,
        inserted_values: &[ValueContainer],
    ) -> Result<Vec<u8>, SpannedCompilerError> {
        let compile_scope = self.compile_scope();
        // TODO #107: don't clone compile_scope if possible
        let res = compile_template(
            script,
            inserted_values
                .iter()
                .cloned()
                .map(Some)
                .collect::<Vec<_>>()
                .as_slice(),
            CompileOptions::new_with_scope(compile_scope.clone()),
        );
        match res {
            Ok((bytes, compile_scope)) => {
                self.set_compile_scope(compile_scope);
                Ok(bytes)
            }
            Err(err) => Err(err),
        }
    }

    fn print_dxb_debug(&self, dxb: &[u8]) -> Result<(), ExecutionError> {
        info!(
            "\x1b[32m[Compiled Bytecode] {}",
            dxb.iter()
                .map(|b| format!("{b:02x}"))
                .collect::<Vec<_>>()
                .join(" ")
        );

        #[cfg(feature = "decompiler")]
        {
            let decompiled = crate::decompiler::decompile_body(
                dxb,
                crate::decompiler::DecompileOptions::colorized(),
            );
            if let Err(e) = decompiled {
                info!("\x1b[31m[Decompiler Error] {e}\x1b[0m");
            } else {
                let decompiled = decompiled?;
                info!("[Decompiled]: {decompiled}");
            }
        }

        Ok(())
    }

    fn get_local_execution_input<'a>(
        &'a mut self,
        dxb: &'a [u8],
    ) -> Result<ExecutionInput<'a>, ExecutionError> {
        match self {
            ExecutionContext::Remote(_) => {
                core::panic!("Remote execution requires a Runtime");
            }
            ExecutionContext::Local(LocalExecutionContext {
                runtime,
                loop_state,
                execution_options,
                verbose,
                ..
            }) => {
                let input = ExecutionInput {
                    runtime: runtime.clone(),
                    loop_state: loop_state.take(),
                    options: (*execution_options).clone(),
                    dxb_body: dxb,
                };

                // show DXB and decompiled code if verbose is enabled
                if *verbose {
                    self.print_dxb_debug(dxb)?;
                }

                Ok(input)
            }
        }
    }

    /// Executes DXB in a local execution context.
    pub fn execute_dxb_sync(
        &mut self,
        dxb: &[u8],
    ) -> Result<Option<ValueContainer>, ExecutionError> {
        let execution_input = self.get_local_execution_input(dxb)?;
        let res = execute_dxb_sync(execution_input);
        self.intercept_intermediate_result(res)
    }

    /// Executes a script in a local execution context.
    #[cfg(feature = "compiler")]
    pub fn execute_sync(
        &mut self,
        script: &str,
        inserted_values: &[ValueContainer],
    ) -> Result<Option<ValueContainer>, ScriptExecutionError> {
        let dxb = self.compile(script, inserted_values)?;
        self.execute_dxb_sync(&dxb)
            .map_err(ScriptExecutionError::from)
    }

    pub async fn execute_dxb(
        &mut self,
        dxb: &[u8],
    ) -> Result<Option<ValueContainer>, ExecutionError> {
        match self {
            ExecutionContext::Local(..) => {
                let res = {
                    let execution_input =
                        self.get_local_execution_input(dxb)?;
                    execute_dxb(execution_input).await
                };
                self.intercept_intermediate_result(res)
            }
            // remote execution is not supported directly in execution context
            ExecutionContext::Remote(..) => {
                core::panic!("Remote execution requires a Runtime");
            }
        }
    }

    /// Intercepts an intermediate execution result,
    /// storing the loop state if present in the execution context and returning the intermediate result as an Ok value.
    /// Note: this function assumes that self is a Local execution context
    fn intercept_intermediate_result(
        &mut self,
        execution_result: Result<Option<ValueContainer>, ExecutionError>,
    ) -> Result<Option<ValueContainer>, ExecutionError> {
        match execution_result {
            Err(ExecutionError::IntermediateResultWithState(
                intermediate_result,
                Some(state),
            )) => {
                match self {
                    ExecutionContext::Local(LocalExecutionContext {
                        loop_state,
                        ..
                    }) => {
                        loop_state.replace(state);
                        Ok(intermediate_result)
                    }
                    _ => unreachable!(), // note: this must be ensured by the caller
                }
            }
            _ => execution_result,
        }
    }

    #[cfg(feature = "compiler")]
    pub async fn execute(
        &mut self,
        script: &str,
        inserted_values: &[ValueContainer],
    ) -> Result<Option<ValueContainer>, ScriptExecutionError> {
        let dxb = self.compile(script, inserted_values)?;
        self.execute_dxb(&dxb)
            .await
            .map_err(ScriptExecutionError::from)
    }

    /// Returns a memory dump of the current state of the execution context if available.
    pub fn memory_dump(&self) -> Option<MemoryDump> {
        match self {
            ExecutionContext::Local(_local_context) => {
                todo!("#650 Undescribed by author.")
                // Some(local_context.memory_dump())
            }
            // TODO #397: also support remote memory dump if possible
            ExecutionContext::Remote(_) => None,
        }
    }
}