use crate::io::story_metadata::{TestPlanStatus, parse_front_matter};
use crate::state::SessionState;
use serde::Serialize;
use std::fs;
use std::path::PathBuf;
use std::process::Command;

/// Helper to get the root path (cloned) without joining
fn get_project_root(state: &SessionState) -> Result<PathBuf, String> {
    state.get_project_root()
}

async fn ensure_test_plan_approved(root: PathBuf) -> Result<(), String> {
    let approved = tokio::task::spawn_blocking(move || {
        let story_path = root
            .join(".story_kit")
            .join("stories")
            .join("current")
            .join("26_establish_tdd_workflow_and_gates.md");
        let contents = fs::read_to_string(&story_path)
            .map_err(|e| format!("Failed to read story file for test plan approval: {e}"))?;
        let metadata = parse_front_matter(&contents)
            .map_err(|e| format!("Failed to parse story front matter: {e:?}"))?;

        Ok::<bool, String>(matches!(metadata.test_plan, Some(TestPlanStatus::Approved)))
    })
    .await
    .map_err(|e| format!("Task failed: {e}"))??;

    if approved {
        Ok(())
    } else {
        Err("Test plan is not approved for the current story.".to_string())
    }
}

#[derive(Serialize, Debug, poem_openapi::Object)]
pub struct CommandOutput {
    pub stdout: String,
    pub stderr: String,
    pub exit_code: i32,
}

/// Execute shell command logic (pure function for testing)
async fn exec_shell_impl(
    command: String,
    args: Vec<String>,
    root: PathBuf,
) -> Result<CommandOutput, String> {
    // Security Allowlist
    let allowed_commands = [
        "git", "cargo", "npm", "yarn", "pnpm", "node", "bun", "ls", "find", "grep", "mkdir", "rm",
        "mv", "cp", "touch", "rustc", "rustfmt",
    ];

    if !allowed_commands.contains(&command.as_str()) {
        return Err(format!("Command '{}' is not in the allowlist.", command));
    }

    let output = tokio::task::spawn_blocking(move || {
        Command::new(&command)
            .args(&args)
            .current_dir(root)
            .output()
    })
    .await
    .map_err(|e| format!("Task join error: {}", e))?
    .map_err(|e| format!("Failed to execute command: {}", e))?;

    Ok(CommandOutput {
        stdout: String::from_utf8_lossy(&output.stdout).to_string(),
        stderr: String::from_utf8_lossy(&output.stderr).to_string(),
        exit_code: output.status.code().unwrap_or(-1),
    })
}

pub async fn exec_shell(
    command: String,
    args: Vec<String>,
    state: &SessionState,
) -> Result<CommandOutput, String> {
    let root = get_project_root(state)?;
    ensure_test_plan_approved(root.clone()).await?;
    exec_shell_impl(command, args, root).await
}

#[cfg(test)]
mod tests {
    use super::*;
    use tempfile::tempdir;

    #[tokio::test]
    async fn exec_shell_requires_approved_test_plan() {
        let dir = tempdir().expect("tempdir");
        let state = SessionState::default();

        {
            let mut root = state.project_root.lock().expect("lock project root");
            *root = Some(dir.path().to_path_buf());
        }

        let result = exec_shell("ls".to_string(), Vec::new(), &state).await;

        assert!(
            result.is_err(),
            "expected shell execution to be blocked when test plan is not approved"
        );
    }

    #[tokio::test]
    async fn exec_shell_impl_rejects_disallowed_command() {
        let dir = tempdir().unwrap();
        let result = exec_shell_impl(
            "curl".to_string(),
            vec!["https://example.com".to_string()],
            dir.path().to_path_buf(),
        )
        .await;

        assert!(result.is_err());
        assert!(result.unwrap_err().contains("not in the allowlist"));
    }

    #[tokio::test]
    async fn exec_shell_impl_runs_allowed_command() {
        let dir = tempdir().unwrap();
        let result = exec_shell_impl(
            "ls".to_string(),
            Vec::new(),
            dir.path().to_path_buf(),
        )
        .await;

        assert!(result.is_ok());
        let output = result.unwrap();
        assert_eq!(output.exit_code, 0);
    }

    #[tokio::test]
    async fn exec_shell_impl_captures_stdout() {
        let dir = tempdir().unwrap();
        std::fs::write(dir.path().join("hello.txt"), "").unwrap();

        let result = exec_shell_impl(
            "ls".to_string(),
            Vec::new(),
            dir.path().to_path_buf(),
        )
        .await
        .unwrap();

        assert!(result.stdout.contains("hello.txt"));
    }

    #[tokio::test]
    async fn exec_shell_impl_returns_nonzero_exit_code() {
        let dir = tempdir().unwrap();
        let result = exec_shell_impl(
            "ls".to_string(),
            vec!["nonexistent_file_xyz".to_string()],
            dir.path().to_path_buf(),
        )
        .await
        .unwrap();

        assert_ne!(result.exit_code, 0);
        assert!(!result.stderr.is_empty());
    }
}