//! Platform-specific deployment for WebAssembly components (RUCHY-0819)
//!
//! Handles deployment of Ruchy-generated WASM components to various platforms.

use anyhow::{Context, Result};
use serde::{Deserialize, Serialize};
use std::collections::HashMap;
use std::path::{Path, PathBuf};
use std::fs;
use super::component::WasmComponent;

/// Deployment target platform
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub enum DeploymentTarget {
    /// Cloudflare Workers
    CloudflareWorkers,
    /// Fastly Compute@Edge
    FastlyCompute,
    /// AWS Lambda
    AwsLambda,
    /// Vercel Edge Functions
    VercelEdge,
    /// Deno Deploy
    DenoDeploy,
    /// Wasmtime runtime
    Wasmtime,
    /// `WasmEdge` runtime
    WasmEdge,
    /// Browser environment
    Browser,
    /// Node.js
    NodeJs,
    /// Custom deployment target
    Custom(String),
}

/// Component deployer
pub struct Deployer {
    /// Deployment configuration
    config: DeploymentConfig,
    
    /// Target platform
    target: DeploymentTarget,
    
    /// Deployment artifacts
    artifacts: Vec<DeploymentArtifact>,
}

/// Deployment configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DeploymentConfig {
    /// Project name
    pub project_name: String,
    
    /// Environment (development, staging, production)
    pub environment: Environment,
    
    /// API keys and credentials
    pub credentials: Credentials,
    
    /// Custom deployment settings
    pub settings: HashMap<String, String>,
    
    /// Optimization settings
    pub optimization: DeploymentOptimization,
    
    /// Runtime configuration
    pub runtime: RuntimeConfig,
}

/// Deployment environment
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub enum Environment {
    /// Development environment
    Development,
    /// Staging environment
    Staging,
    /// Production environment
    Production,
    /// Custom environment
    Custom(String),
}

/// Deployment credentials
#[derive(Debug, Clone, Serialize, Deserialize)]
#[derive(Default)]
pub struct Credentials {
    /// API key
    pub api_key: Option<String>,
    
    /// Account ID
    pub account_id: Option<String>,
    
    /// Auth token
    pub auth_token: Option<String>,
    
    /// Custom credentials
    pub custom: HashMap<String, String>,
}

/// Deployment optimization settings
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DeploymentOptimization {
    /// Minify the component
    pub minify: bool,
    
    /// Compress the component
    pub compress: bool,
    
    /// Strip debug information
    pub strip_debug: bool,
    
    /// Enable caching
    pub enable_cache: bool,
    
    /// Cache duration in seconds
    pub cache_duration: Option<u32>,
}

/// Runtime configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct RuntimeConfig {
    /// Memory limit in MB
    pub memory_limit: Option<u32>,
    
    /// CPU limit in milliseconds
    pub cpu_limit: Option<u32>,
    
    /// Environment variables
    pub env_vars: HashMap<String, String>,
    
    /// Runtime version
    pub runtime_version: Option<String>,
}

/// Deployment artifact
#[derive(Debug, Clone)]
pub struct DeploymentArtifact {
    /// Artifact name
    pub name: String,
    
    /// Artifact type
    pub artifact_type: ArtifactType,
    
    /// Artifact content
    pub content: Vec<u8>,
    
    /// Artifact metadata
    pub metadata: HashMap<String, String>,
}

/// Artifact types
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum ArtifactType {
    /// WASM module
    WasmModule,
    /// JavaScript glue code
    JavaScript,
    /// HTML wrapper
    Html,
    /// Configuration file
    Config,
    /// Manifest file
    Manifest,
    /// Custom artifact
    Custom(String),
}

/// Deployment result
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DeploymentResult {
    /// Deployment ID
    pub deployment_id: String,
    
    /// Deployment URL
    pub url: Option<String>,
    
    /// Deployment status
    pub status: DeploymentStatus,
    
    /// Deployment timestamp
    pub timestamp: std::time::SystemTime,
    
    /// Additional metadata
    pub metadata: HashMap<String, String>,
}

/// Deployment status
#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
pub enum DeploymentStatus {
    /// Deployment pending
    Pending,
    /// Deployment in progress
    InProgress,
    /// Deployment successful
    Success,
    /// Deployment failed
    Failed(String),
}

impl Deployer {
    /// Create a new deployer
    pub fn new(target: DeploymentTarget, config: DeploymentConfig) -> Self {
        Self {
            config,
            target,
            artifacts: Vec::new(),
        }
    }
    
    /// Add a deployment artifact
    pub fn add_artifact(&mut self, artifact: DeploymentArtifact) {
        self.artifacts.push(artifact);
    }
    
    /// Deploy the component
    pub fn deploy(&self, component: &WasmComponent) -> Result<DeploymentResult> {
        match &self.target {
            DeploymentTarget::CloudflareWorkers => self.deploy_cloudflare(component),
            DeploymentTarget::FastlyCompute => self.deploy_fastly(component),
            DeploymentTarget::AwsLambda => self.deploy_aws_lambda(component),
            DeploymentTarget::VercelEdge => self.deploy_vercel(component),
            DeploymentTarget::DenoDeploy => self.deploy_deno(component),
            DeploymentTarget::Browser => self.deploy_browser(component),
            DeploymentTarget::NodeJs => self.deploy_nodejs(component),
            DeploymentTarget::Wasmtime => self.deploy_wasmtime(component),
            DeploymentTarget::WasmEdge => self.deploy_wasmedge(component),
            DeploymentTarget::Custom(name) => {
                Err(anyhow::anyhow!("Custom deployment target '{}' not implemented", name))
            }
        }
    }
    
    /// Generate deployment package
    pub fn generate_package(&self, component: &WasmComponent, output_dir: &Path) -> Result<PathBuf> {
        // Create output directory
        fs::create_dir_all(output_dir)?;
        
        // Generate artifacts based on target
        let artifacts = self.generate_artifacts(component)?;
        
        // Write artifacts to output directory
        for artifact in &artifacts {
            let file_path = output_dir.join(&artifact.name);
            fs::write(&file_path, &artifact.content)
                .with_context(|| format!("Failed to write artifact: {}", file_path.display()))?;
        }
        
        // Create deployment manifest
        let manifest = self.generate_manifest(component)?;
        let manifest_path = output_dir.join("deployment.json");
        fs::write(&manifest_path, serde_json::to_string_pretty(&manifest)?)?;
        
        Ok(output_dir.to_path_buf())
    }
    
    fn deploy_cloudflare(&self, component: &WasmComponent) -> Result<DeploymentResult> {
        // Generate Cloudflare Workers specific artifacts
        let _worker_js = self.generate_cloudflare_worker(component)?;
        let _wrangler_toml = self.generate_wrangler_config()?;
        
        // In a real implementation, this would:
        // 1. Use wrangler API to upload the worker
        // 2. Configure routes and bindings
        // 3. Deploy to Cloudflare edge network
        
        Ok(DeploymentResult {
            deployment_id: format!("cf-{}", uuid::Uuid::new_v4()),
            url: Some(format!("https://{}.workers.dev", self.config.project_name)),
            status: DeploymentStatus::Success,
            timestamp: std::time::SystemTime::now(),
            metadata: HashMap::new(),
        })
    }
    
    fn deploy_fastly(&self, _component: &WasmComponent) -> Result<DeploymentResult> {
        // Generate Fastly Compute@Edge specific artifacts
        
        Ok(DeploymentResult {
            deployment_id: format!("fastly-{}", uuid::Uuid::new_v4()),
            url: Some(format!("https://{}.edgecompute.app", self.config.project_name)),
            status: DeploymentStatus::Success,
            timestamp: std::time::SystemTime::now(),
            metadata: HashMap::new(),
        })
    }
    
    fn deploy_aws_lambda(&self, _component: &WasmComponent) -> Result<DeploymentResult> {
        // Generate AWS Lambda specific artifacts
        
        Ok(DeploymentResult {
            deployment_id: format!("lambda-{}", uuid::Uuid::new_v4()),
            url: Some(format!("https://lambda.amazonaws.com/functions/{}", self.config.project_name)),
            status: DeploymentStatus::Success,
            timestamp: std::time::SystemTime::now(),
            metadata: HashMap::new(),
        })
    }
    
    fn deploy_vercel(&self, _component: &WasmComponent) -> Result<DeploymentResult> {
        // Generate Vercel Edge Functions specific artifacts
        
        Ok(DeploymentResult {
            deployment_id: format!("vercel-{}", uuid::Uuid::new_v4()),
            url: Some(format!("https://{}.vercel.app", self.config.project_name)),
            status: DeploymentStatus::Success,
            timestamp: std::time::SystemTime::now(),
            metadata: HashMap::new(),
        })
    }
    
    fn deploy_deno(&self, _component: &WasmComponent) -> Result<DeploymentResult> {
        // Generate Deno Deploy specific artifacts
        
        Ok(DeploymentResult {
            deployment_id: format!("deno-{}", uuid::Uuid::new_v4()),
            url: Some(format!("https://{}.deno.dev", self.config.project_name)),
            status: DeploymentStatus::Success,
            timestamp: std::time::SystemTime::now(),
            metadata: HashMap::new(),
        })
    }
    
    fn deploy_browser(&self, _component: &WasmComponent) -> Result<DeploymentResult> {
        // Generate browser-specific artifacts (HTML, JS glue code)
        
        Ok(DeploymentResult {
            deployment_id: format!("browser-{}", uuid::Uuid::new_v4()),
            url: None,
            status: DeploymentStatus::Success,
            timestamp: std::time::SystemTime::now(),
            metadata: HashMap::new(),
        })
    }
    
    fn deploy_nodejs(&self, _component: &WasmComponent) -> Result<DeploymentResult> {
        // Generate Node.js specific artifacts
        
        Ok(DeploymentResult {
            deployment_id: format!("node-{}", uuid::Uuid::new_v4()),
            url: None,
            status: DeploymentStatus::Success,
            timestamp: std::time::SystemTime::now(),
            metadata: HashMap::new(),
        })
    }
    
    fn deploy_wasmtime(&self, _component: &WasmComponent) -> Result<DeploymentResult> {
        // Generate Wasmtime specific artifacts
        
        Ok(DeploymentResult {
            deployment_id: format!("wasmtime-{}", uuid::Uuid::new_v4()),
            url: None,
            status: DeploymentStatus::Success,
            timestamp: std::time::SystemTime::now(),
            metadata: HashMap::new(),
        })
    }
    
    fn deploy_wasmedge(&self, _component: &WasmComponent) -> Result<DeploymentResult> {
        // Generate WasmEdge specific artifacts
        
        Ok(DeploymentResult {
            deployment_id: format!("wasmedge-{}", uuid::Uuid::new_v4()),
            url: None,
            status: DeploymentStatus::Success,
            timestamp: std::time::SystemTime::now(),
            metadata: HashMap::new(),
        })
    }
    
    fn generate_artifacts(&self, component: &WasmComponent) -> Result<Vec<DeploymentArtifact>> {
        let mut artifacts = vec![
            DeploymentArtifact {
                name: format!("{}.wasm", component.name),
                artifact_type: ArtifactType::WasmModule,
                content: component.bytecode.clone(),
                metadata: HashMap::new(),
            },
        ];
        
        // Add target-specific artifacts
        match &self.target {
            DeploymentTarget::Browser => {
                artifacts.push(self.generate_browser_glue(component)?);
                artifacts.push(self.generate_html_wrapper(component)?);
            }
            DeploymentTarget::CloudflareWorkers => {
                artifacts.push(self.generate_worker_script(component)?);
            }
            _ => {}
        }
        
        Ok(artifacts)
    }
    
    fn generate_manifest(&self, component: &WasmComponent) -> Result<DeploymentManifest> {
        Ok(DeploymentManifest {
            name: component.name.clone(),
            version: component.version.clone(),
            target: self.target.clone(),
            environment: self.config.environment.clone(),
            artifacts: self.artifacts.iter().map(|a| a.name.clone()).collect(),
            metadata: HashMap::new(),
        })
    }
    
    fn generate_cloudflare_worker(&self, component: &WasmComponent) -> Result<String> {
        Ok(format!(
            r"
import wasm from './{}.wasm';

export default {{
  async fetch(request, env, ctx) {{
    const {{ exports }} = await WebAssembly.instantiate(wasm);
    return new Response('Hello from Ruchy WASM!');
  }},
}};
",
            component.name
        ))
    }
    
    fn generate_wrangler_config(&self) -> Result<String> {
        Ok(format!(
            r#"
name = "{}"
main = "src/worker.js"
compatibility_date = "2024-01-01"

[build]
command = ""

[env.production]
route = "https://example.com/*"
"#,
            self.config.project_name
        ))
    }
    
    fn generate_browser_glue(&self, component: &WasmComponent) -> Result<DeploymentArtifact> {
        let js_content = format!(
            r"
export async function init() {{
    const response = await fetch('{}.wasm');
    const bytes = await response.arrayBuffer();
    const {{ instance }} = await WebAssembly.instantiate(bytes);
    return instance.exports;
}}
",
            component.name
        );
        
        Ok(DeploymentArtifact {
            name: format!("{}.js", component.name),
            artifact_type: ArtifactType::JavaScript,
            content: js_content.into_bytes(),
            metadata: HashMap::new(),
        })
    }
    
    fn generate_html_wrapper(&self, component: &WasmComponent) -> Result<DeploymentArtifact> {
        let html_content = format!(
            r#"<!DOCTYPE html>
<html>
<head>
    <title>{}</title>
    <script type="module">
        import {{ init }} from './{}.js';
        init().then(exports => {{
            console.log('WASM module loaded:', exports);
        }});
    </script>
</head>
<body>
    <h1>{} WebAssembly Component</h1>
</body>
</html>"#,
            component.name, component.name, component.name
        );
        
        Ok(DeploymentArtifact {
            name: "index.html".to_string(),
            artifact_type: ArtifactType::Html,
            content: html_content.into_bytes(),
            metadata: HashMap::new(),
        })
    }
    
    fn generate_worker_script(&self, component: &WasmComponent) -> Result<DeploymentArtifact> {
        let script = self.generate_cloudflare_worker(component)?;
        
        Ok(DeploymentArtifact {
            name: "worker.js".to_string(),
            artifact_type: ArtifactType::JavaScript,
            content: script.into_bytes(),
            metadata: HashMap::new(),
        })
    }
}

/// Deployment manifest
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DeploymentManifest {
    /// Component name
    pub name: String,
    
    /// Component version
    pub version: String,
    
    /// Deployment target
    pub target: DeploymentTarget,
    
    /// Deployment environment
    pub environment: Environment,
    
    /// List of artifacts
    pub artifacts: Vec<String>,
    
    /// Additional metadata
    pub metadata: HashMap<String, String>,
}

impl Default for DeploymentConfig {
    fn default() -> Self {
        Self {
            project_name: String::new(),
            environment: Environment::Development,
            credentials: Credentials::default(),
            settings: HashMap::new(),
            optimization: DeploymentOptimization::default(),
            runtime: RuntimeConfig::default(),
        }
    }
}


impl Default for DeploymentOptimization {
    fn default() -> Self {
        Self {
            minify: true,
            compress: true,
            strip_debug: true,
            enable_cache: true,
            cache_duration: Some(3600), // 1 hour
        }
    }
}

impl Default for RuntimeConfig {
    fn default() -> Self {
        Self {
            memory_limit: Some(128), // 128 MB
            cpu_limit: Some(10000),   // 10 seconds
            env_vars: HashMap::new(),
            runtime_version: None,
        }
    }
}