orbit-tui 1.1.2

//! Resource Fetcher - Generic fetch function driven by JSON config
//!
//! This module provides a single generic function to fetch any AWS resource.
//! All the logic is driven by the resources.json configuration.
//!
//! Resources with `api_config` defined will use data-driven dispatch,
//! while legacy resources (S3 objects, STS) use the legacy invoke_sdk.

use super::dispatch::{invoke_list, invoke_sdk};
use super::registry::get_resource;
use crate::aws::client::AwsClients;
use anyhow::{anyhow, Result};
use serde_json::Value;

/// Filter for fetching resources (used for sub-resource filtering)
#[derive(Debug, Clone, Default)]
pub struct ResourceFilter {
    pub name: String,
    pub values: Vec<String>,
    /// Filter type: "scalar" (default) for single-value params,
    /// "ec2_filter" for EC2-style Filter.N.Name/Value params
    pub filter_type: String,
}

impl ResourceFilter {
    pub fn new(name: &str, values: Vec<String>) -> Self {
        Self {
            name: name.to_string(),
            values,
            filter_type: "scalar".to_string(),
        }
    }

    pub fn with_type(name: &str, values: Vec<String>, filter_type: &str) -> Self {
        Self {
            name: name.to_string(),
            values,
            filter_type: filter_type.to_string(),
        }
    }
}

/// Result from paginated fetch including items and next page token
#[derive(Debug, Clone)]
pub struct PaginatedResult {
    pub items: Vec<Value>,
    pub next_token: Option<String>,
}

/// Fetch resources with pagination support
///
/// Returns items for the current page and the next_token for fetching more
///
/// Resources with `api_config` will use the new data-driven dispatch,
/// while legacy resources use the old sdk_dispatch.
pub async fn fetch_resources_paginated(
    resource_key: &str,
    clients: &AwsClients,
    filters: &[ResourceFilter],
    page_token: Option<&str>,
) -> Result<PaginatedResult> {
    // 1. Look up resource definition from JSON
    let resource_def =
        get_resource(resource_key).ok_or_else(|| anyhow!("Unknown resource: {}", resource_key))?;

    // 2. Build params (merge default params with filters)
    let mut params = resource_def.sdk_method_params.clone();

    // Add filters to params if any
    if !filters.is_empty() {
        if let Value::Object(ref mut map) = params {
            for filter in filters {
                match filter.filter_type.as_str() {
                    "ec2_filter" => {
                        // EC2-style filters use Filter.N.Name/Value format
                        // Use "filter:" prefix which query.rs handles specially
                        let filter_key = format!("filter:{}", filter.name);
                        map.insert(
                            filter_key,
                            Value::Array(
                                filter
                                    .values
                                    .iter()
                                    .map(|v| Value::String(v.clone()))
                                    .collect(),
                            ),
                        );
                    }
                    _ => {
                        // "scalar" (default): single value as string, multiple as array
                        let value = if filter.values.len() == 1 {
                            Value::String(filter.values[0].clone())
                        } else {
                            Value::Array(
                                filter
                                    .values
                                    .iter()
                                    .map(|v| Value::String(v.clone()))
                                    .collect(),
                            )
                        };
                        map.insert(filter.name.clone(), value);
                    }
                }
            }
        }
    }

    // Add pagination token if provided
    if let Some(token) = page_token {
        if let Value::Object(ref mut map) = params {
            map.insert("_page_token".to_string(), Value::String(token.to_string()));
        }
    }

    // 3. Call SDK dispatcher - use new data-driven dispatch if api_config is defined
    let response = if resource_def.has_api_config() {
        invoke_list(resource_key, clients, &params).await?
    } else {
        // Legacy path: use old sdk_dispatch
        invoke_sdk(
            &resource_def.service,
            &resource_def.sdk_method,
            clients,
            &params,
        )
        .await?
    };

    // 4. Extract items using response_path
    let mut items = extract_items(&response, &resource_def.response_path)?;

    // 5. Sort items by name_field (or id_field) for consistent ordering
    //    Skip sorting if the resource wants to preserve API order (e.g., events sorted by time)
    if !resource_def.preserve_order {
        let sort_field = &resource_def.name_field;
        items.sort_by(|a, b| {
            let a_val = a.get(sort_field).and_then(|v| v.as_str()).unwrap_or("");
            let b_val = b.get(sort_field).and_then(|v| v.as_str()).unwrap_or("");
            a_val.cmp(b_val)
        });
    }

    // 6. Extract next_token from response (if present)
    let next_token = response
        .get("_next_token")
        .and_then(|v| v.as_str())
        .map(|s| s.to_string());

    Ok(PaginatedResult { items, next_token })
}

/// Extract items array from response using the response_path
fn extract_items(response: &Value, path: &str) -> Result<Vec<Value>> {
    // Simple path extraction (e.g., "users", "roles")
    // For nested paths, split by '.' and traverse
    let parts: Vec<&str> = path.split('.').collect();

    let mut current = response.clone();
    for part in parts {
        current = current
            .get(part)
            .cloned()
            .ok_or_else(|| anyhow!("Path '{}' not found in response", path))?;
    }

    // Expect an array
    match current {
        Value::Array(arr) => Ok(arr),
        _ => Err(anyhow!(
            "Expected array at path '{}', got {:?}",
            path,
            current
        )),
    }
}

/// Extract a value from a JSON object using dot notation path
/// Supports: "Field", "Field.SubField", "Field.0", "Tags.Name"
pub fn extract_json_value(item: &Value, path: &str) -> String {
    let parts: Vec<&str> = path.split('.').collect();
    let mut current = item.clone();

    for part in parts {
        current = match current {
            Value::Object(map) => {
                // Special handling for Tags.Name pattern
                if part == "Name" && map.contains_key("Tags") {
                    if let Some(Value::Object(tags)) = map.get("Tags") {
                        if let Some(Value::String(name)) = tags.get("Name") {
                            return name.clone();
                        }
                    }
                }
                map.get(part).cloned().unwrap_or(Value::Null)
            }
            Value::Array(arr) => {
                // Handle numeric index or "length"
                if part == "length" {
                    return arr.len().to_string();
                }
                if let Ok(idx) = part.parse::<usize>() {
                    arr.get(idx).cloned().unwrap_or(Value::Null)
                } else {
                    Value::Null
                }
            }
            _ => Value::Null,
        };
    }

    // Convert final value to string
    match current {
        Value::String(s) => s,
        Value::Number(n) => n.to_string(),
        Value::Bool(b) => {
            if b {
                "Yes".to_string()
            } else {
                "No".to_string()
            }
        }
        Value::Null => "-".to_string(),
        _ => "-".to_string(),
    }
}