use application::processing::{ExecutePipelineCommand, ExecutePipelineHandler};
use application::testing::{
    InMemoryJobBatchRepository, InMemoryJobRepository, InMemoryPipelineRepository,
    InMemoryPluginRepository, StubEventPublisher,
};
use async_trait::async_trait;
use domain::{
    entities::{Job, JobStatus, JobType, Plugin, PluginType, ProcessingPipeline},
    errors::DomainError,
    ports::{JobRepository, PipelineRepository, PluginExecutor, PluginRegistry, PluginRepository},
    value_objects::{MetadataValue, StructuredData, SystemId},
};
use std::collections::HashMap;
use std::sync::Arc;

struct StubPluginExecutor {
    name: String,
    result: StructuredData,
}

#[async_trait]
impl PluginExecutor for StubPluginExecutor {
    fn plugin_name(&self) -> &str {
        &self.name
    }

    async fn execute(
        &self,
        _asset_id: Option<SystemId>,
        _payload: &StructuredData,
        _config: &StructuredData,
    ) -> Result<StructuredData, DomainError> {
        Ok(self.result.clone())
    }
}

struct FailingPluginExecutor;

#[async_trait]
impl PluginExecutor for FailingPluginExecutor {
    fn plugin_name(&self) -> &str {
        "failing"
    }

    async fn execute(
        &self,
        _asset_id: Option<SystemId>,
        _payload: &StructuredData,
        _config: &StructuredData,
    ) -> Result<StructuredData, DomainError> {
        Err(DomainError::Internal("plugin crashed".into()))
    }
}

struct TestPluginRegistry {
    executors: HashMap<String, Arc<dyn PluginExecutor>>,
}

impl TestPluginRegistry {
    fn new() -> Self {
        Self {
            executors: HashMap::new(),
        }
    }

    fn with(mut self, executor: Arc<dyn PluginExecutor>) -> Self {
        self.executors
            .insert(executor.plugin_name().to_string(), executor);
        self
    }
}

impl PluginRegistry for TestPluginRegistry {
    fn get_executor(&self, plugin_name: &str) -> Option<Arc<dyn PluginExecutor>> {
        self.executors.get(plugin_name).cloned()
    }

    fn registered_plugins(&self) -> Vec<String> {
        self.executors.keys().cloned().collect()
    }
}

fn make_handler(
    job_repo: Arc<InMemoryJobRepository>,
    batch_repo: Arc<InMemoryJobBatchRepository>,
    pipeline_repo: Arc<InMemoryPipelineRepository>,
    plugin_repo: Arc<InMemoryPluginRepository>,
    registry: Arc<dyn PluginRegistry>,
) -> ExecutePipelineHandler {
    let event_pub = Arc::new(StubEventPublisher::new());
    ExecutePipelineHandler::new(
        job_repo,
        batch_repo,
        pipeline_repo,
        plugin_repo,
        registry,
        event_pub,
    )
}

async fn seed_plugin(repo: &InMemoryPluginRepository, name: &str) -> Plugin {
    let plugin = Plugin::new(name, PluginType::MediaProcessor);
    repo.save(&plugin).await.unwrap();
    plugin
}

async fn seed_pipeline(
    repo: &InMemoryPipelineRepository,
    trigger: &str,
    plugin: &Plugin,
) -> ProcessingPipeline {
    let mut pipeline = ProcessingPipeline::new(trigger);
    pipeline.add_step(plugin.plugin_id, StructuredData::new());
    repo.save(&pipeline).await.unwrap();
    pipeline
}

async fn seed_job(repo: &InMemoryJobRepository, job_type: JobType) -> Job {
    let job = Job::new(job_type, 10, StructuredData::new());
    repo.save(&job).await.unwrap();
    job
}

#[tokio::test]
async fn executes_pipeline_with_one_step() {
    let job_repo = Arc::new(InMemoryJobRepository::new());
    let batch_repo = Arc::new(InMemoryJobBatchRepository::new());
    let pipeline_repo = Arc::new(InMemoryPipelineRepository::new());
    let plugin_repo = Arc::new(InMemoryPluginRepository::new());

    let plugin = seed_plugin(&plugin_repo, "test_plugin").await;
    seed_pipeline(&pipeline_repo, "extract_metadata", &plugin).await;
    let job = seed_job(&job_repo, JobType::ExtractMetadata).await;

    let mut result_data = StructuredData::new();
    result_data.insert("key", MetadataValue::String("value".into()));
    let executor = Arc::new(StubPluginExecutor {
        name: "test_plugin".into(),
        result: result_data,
    });
    let registry = Arc::new(TestPluginRegistry::new().with(executor));

    let handler = make_handler(
        job_repo.clone(),
        batch_repo,
        pipeline_repo,
        plugin_repo,
        registry,
    );

    let result = handler
        .execute(ExecutePipelineCommand { job_id: job.job_id })
        .await
        .unwrap();

    assert_eq!(result.status, JobStatus::Completed);
    assert_eq!(result.result_data.unwrap().get_string("key"), Some("value"));
}

#[tokio::test]
async fn falls_back_to_direct_executor_when_no_pipeline() {
    let job_repo = Arc::new(InMemoryJobRepository::new());
    let batch_repo = Arc::new(InMemoryJobBatchRepository::new());
    let pipeline_repo = Arc::new(InMemoryPipelineRepository::new());
    let plugin_repo = Arc::new(InMemoryPluginRepository::new());

    let job = seed_job(&job_repo, JobType::ExtractMetadata).await;

    let executor = Arc::new(StubPluginExecutor {
        name: "extract_metadata".into(),
        result: StructuredData::new(),
    });
    let registry = Arc::new(TestPluginRegistry::new().with(executor));

    let handler = make_handler(
        job_repo.clone(),
        batch_repo,
        pipeline_repo,
        plugin_repo,
        registry,
    );

    let result = handler
        .execute(ExecutePipelineCommand { job_id: job.job_id })
        .await
        .unwrap();

    assert_eq!(result.status, JobStatus::Completed);
}

#[tokio::test]
async fn skips_disabled_plugin() {
    let job_repo = Arc::new(InMemoryJobRepository::new());
    let batch_repo = Arc::new(InMemoryJobBatchRepository::new());
    let pipeline_repo = Arc::new(InMemoryPipelineRepository::new());
    let plugin_repo = Arc::new(InMemoryPluginRepository::new());

    let mut plugin = Plugin::new("disabled_one", PluginType::MediaProcessor);
    plugin.disable();
    plugin_repo.save(&plugin).await.unwrap();

    seed_pipeline(&pipeline_repo, "extract_metadata", &plugin).await;
    let job = seed_job(&job_repo, JobType::ExtractMetadata).await;

    let registry = Arc::new(TestPluginRegistry::new());

    let handler = make_handler(
        job_repo.clone(),
        batch_repo,
        pipeline_repo,
        plugin_repo,
        registry,
    );

    let result = handler
        .execute(ExecutePipelineCommand { job_id: job.job_id })
        .await
        .unwrap();

    assert_eq!(result.status, JobStatus::Completed);
}

#[tokio::test]
async fn step_failure_fails_job_with_retry() {
    let job_repo = Arc::new(InMemoryJobRepository::new());
    let batch_repo = Arc::new(InMemoryJobBatchRepository::new());
    let pipeline_repo = Arc::new(InMemoryPipelineRepository::new());
    let plugin_repo = Arc::new(InMemoryPluginRepository::new());

    let plugin = seed_plugin(&plugin_repo, "failing").await;
    seed_pipeline(&pipeline_repo, "extract_metadata", &plugin).await;
    let job = seed_job(&job_repo, JobType::ExtractMetadata).await;

    let executor: Arc<dyn PluginExecutor> = Arc::new(FailingPluginExecutor);
    let registry = Arc::new(TestPluginRegistry::new().with(executor));

    let handler = make_handler(
        job_repo.clone(),
        batch_repo,
        pipeline_repo,
        plugin_repo,
        registry,
    );

    let result = handler
        .execute(ExecutePipelineCommand { job_id: job.job_id })
        .await
        .unwrap();

    // First failure → retry_count=1, back to Queued (max_retries=3)
    assert_eq!(result.status, JobStatus::Queued);
    assert_eq!(result.retry_count, 1);
    assert!(result.error_message.unwrap().contains("plugin crashed"));
}

#[tokio::test]
async fn missing_job_returns_not_found() {
    let job_repo = Arc::new(InMemoryJobRepository::new());
    let batch_repo = Arc::new(InMemoryJobBatchRepository::new());
    let pipeline_repo = Arc::new(InMemoryPipelineRepository::new());
    let plugin_repo = Arc::new(InMemoryPluginRepository::new());
    let registry = Arc::new(TestPluginRegistry::new());

    let handler = make_handler(job_repo, batch_repo, pipeline_repo, plugin_repo, registry);

    let err = handler
        .execute(ExecutePipelineCommand {
            job_id: SystemId::new(),
        })
        .await
        .unwrap_err();

    assert!(matches!(err, DomainError::NotFound(_)));
}