use crate::api::{ApiError, AuthUser};
use crate::audit_log;
use crate::control_plane::{
    AdminNodesResponse, CreateNetworkRequest as CpCreateNetworkRequest,
    CreateTokenRequest as CpCreateTokenRequest, CreateTokenResponse, EnrollmentToken,
    KeyHistoryResponse, KeyPolicyResponse, KeyRotationRequest, KeyRotationResponse,
    KeyRotationPolicy, NetworkInfo,
};
use crate::models::{ControlPlane, Network};
use crate::permissions::{
    ensure_permission_global, PERM_ACL_READ, PERM_ACL_WRITE, PERM_KEY_POLICY_READ,
    PERM_KEY_POLICY_WRITE, PERM_NETWORKS_READ, PERM_NETWORKS_WRITE, PERM_NODES_READ,
    PERM_NODES_WRITE, PERM_TOKENS_WRITE, PERM_AUDIT_READ,
};
use axum::extract::{Path, Query, State};
use axum::http::StatusCode;
use axum::routing::{get, post};
use axum::{Json, Router};
use serde::{Deserialize, Serialize};
use serde_json::Value;
use sqlx::PgPool;
use time::OffsetDateTime;
use uuid::Uuid;

#[derive(Debug, Serialize)]
struct NetworkSummary {
    id: Uuid,
    control_plane_id: Uuid,
    control_plane_name: String,
    network_id: String,
    name: String,
    dns_domain: Option<String>,
    overlay_v4: Option<String>,
    overlay_v6: Option<String>,
    requires_approval: bool,
    created_at: OffsetDateTime,
    updated_at: OffsetDateTime,
}

#[derive(Debug, Deserialize)]
struct CreateNetworkRequest {
    control_plane_id: Uuid,
    name: String,
    overlay_v4: Option<String>,
    overlay_v6: Option<String>,
    dns_domain: Option<String>,
    requires_approval: Option<bool>,
    key_rotation_max_age_seconds: Option<u64>,
    bootstrap_token_ttl_seconds: Option<u64>,
    bootstrap_token_uses: Option<u32>,
    bootstrap_token_tags: Option<Vec<String>>,
}

#[derive(Debug, Serialize)]
struct CreateNetworkResult {
    network: NetworkSummary,
    bootstrap_token: Option<EnrollmentToken>,
}

#[derive(Debug, Deserialize)]
struct CreateTokenRequest {
    ttl_seconds: u64,
    uses: u32,
    tags: Vec<String>,
}

#[derive(Debug, Deserialize)]
struct RevokeTokenRequest {
    token_id: String,
}

#[derive(Debug, Deserialize)]
struct RotateKeysRequest {
    machine_public_key: Option<String>,
    wg_public_key: Option<String>,
}

#[derive(Debug, Deserialize)]
struct UpdateAclRequest {
    policy: Value,
}

#[derive(Debug, Deserialize)]
struct NetworkAuditQuery {
    node_id: Option<String>,
    limit: Option<usize>,
}

pub fn router() -> Router<crate::app_state::AppState> {
    Router::new()
        .route("/", get(list_networks).post(create_network))
        .route("/:id", get(get_network).delete(delete_network))
        .route("/:id/tokens", post(create_token))
        .route("/:id/tokens/revoke", post(revoke_token))
        .route("/:id/nodes", get(list_nodes))
        .route("/:id/nodes/:node_id/approve", post(approve_node))
        .route("/:id/nodes/:node_id/revoke", post(revoke_node))
        .route("/:id/nodes/:node_id/rotate-keys", post(rotate_keys))
        .route("/:id/nodes/:node_id/keys", get(node_keys))
        .route("/:id/acl", get(get_acl).put(update_acl))
        .route("/:id/key-policy", get(get_key_policy).put(update_key_policy))
        .route("/:id/audit", get(network_audit))
}

async fn list_networks(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
) -> Result<Json<Vec<NetworkSummary>>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_NETWORKS_READ).await?;
    let rows = sqlx::query_as::<_, NetworkRow>(
        r#"
        SELECT n.id,
               n.control_plane_id,
               n.network_id,
               n.name,
               n.dns_domain,
               n.overlay_v4,
               n.overlay_v6,
               n.requires_approval,
               n.created_at,
               n.updated_at,
               c.name AS control_plane_name
        FROM networks n
        JOIN control_planes c ON c.id = n.control_plane_id
        ORDER BY n.created_at DESC
        "#,
    )
    .fetch_all(&state.pool)
    .await
    .map_err(|_| ApiError::Internal)?;

    let out = rows
        .into_iter()
        .map(|row| NetworkSummary {
            id: row.id,
            control_plane_id: row.control_plane_id,
            control_plane_name: row.control_plane_name,
            network_id: row.network_id,
            name: row.name,
            dns_domain: row.dns_domain,
            overlay_v4: row.overlay_v4,
            overlay_v6: row.overlay_v6,
            requires_approval: row.requires_approval,
            created_at: row.created_at,
            updated_at: row.updated_at,
        })
        .collect();

    Ok(Json(out))
}

async fn get_network(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path(id): Path<Uuid>,
) -> Result<Json<NetworkSummary>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_NETWORKS_READ).await?;
    let row = fetch_network_summary(&state.pool, id).await?;
    Ok(Json(NetworkSummary {
        id: row.id,
        control_plane_id: row.control_plane_id,
        control_plane_name: row.control_plane_name,
        network_id: row.network_id,
        name: row.name,
        dns_domain: row.dns_domain,
        overlay_v4: row.overlay_v4,
        overlay_v6: row.overlay_v6,
        requires_approval: row.requires_approval,
        created_at: row.created_at,
        updated_at: row.updated_at,
    }))
}

async fn delete_network(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path(id): Path<Uuid>,
) -> Result<StatusCode, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_NETWORKS_WRITE).await?;
    let (network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    
    // Send delete request to control plane
    client
        .delete_network(&network.network_id)
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;
    
    // Delete from database
    sqlx::query("DELETE FROM networks WHERE id = $1")
        .bind(id)
        .execute(&state.pool)
        .await
        .map_err(|_| ApiError::Internal)?;

    audit_log::record(
        &state.pool,
        Some(user.id),
        "network.delete",
        Some("network"),
        Some(&network.id.to_string()),
        Some(serde_json::json!({
            "network_id": network.network_id,
            "control_plane_id": control_plane.id,
        })),
    )
    .await?;

    Ok(StatusCode::NO_CONTENT)
}

async fn create_network(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Json(req): Json<CreateNetworkRequest>,
) -> Result<Json<CreateNetworkResult>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_NETWORKS_WRITE).await?;
    let control_plane = fetch_control_plane(&state.pool, req.control_plane_id).await?;
    let client = crate::control_plane::ControlPlaneClient::new(
        control_plane.base_url.clone(),
        control_plane.admin_token.clone(),
    );

    let response = client
        .create_network(CpCreateNetworkRequest {
            name: req.name,
            overlay_v4: req.overlay_v4.clone(),
            overlay_v6: req.overlay_v6.clone(),
            dns_domain: req.dns_domain.clone(),
            requires_approval: req.requires_approval,
            key_rotation_max_age_seconds: req.key_rotation_max_age_seconds,
            bootstrap_token_ttl_seconds: req.bootstrap_token_ttl_seconds,
            bootstrap_token_uses: req.bootstrap_token_uses,
            bootstrap_token_tags: req.bootstrap_token_tags.clone(),
        })
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;

    let record = insert_network(
        &state.pool,
        &control_plane,
        &response.network,
        req.dns_domain,
    )
    .await?;

    audit_log::record(
        &state.pool,
        Some(user.id),
        "network.create",
        Some("network"),
        Some(&record.id.to_string()),
        Some(serde_json::json!({
            "network_id": response.network.id,
            "control_plane_id": control_plane.id,
        })),
    )
    .await?;

    let summary = fetch_network_summary(&state.pool, record.id).await?;
    Ok(Json(CreateNetworkResult {
        network: NetworkSummary {
            id: summary.id,
            control_plane_id: summary.control_plane_id,
            control_plane_name: summary.control_plane_name,
            network_id: summary.network_id,
            name: summary.name,
            dns_domain: summary.dns_domain,
            overlay_v4: summary.overlay_v4,
            overlay_v6: summary.overlay_v6,
            requires_approval: summary.requires_approval,
            created_at: summary.created_at,
            updated_at: summary.updated_at,
        },
        bootstrap_token: response.bootstrap_token,
    }))
}

async fn create_token(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path(id): Path<Uuid>,
    Json(req): Json<CreateTokenRequest>,
) -> Result<Json<CreateTokenResponse>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_TOKENS_WRITE).await?;
    let (network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    let response = client
        .create_token(
            &network.network_id,
            CpCreateTokenRequest {
                ttl_seconds: req.ttl_seconds,
                uses: req.uses,
                tags: req.tags,
                owner_user_id: Some(user.id.to_string()),
                owner_email: Some(user.email.clone()),
                owner_is_admin: Some(true),
            },
        )
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;

    audit_log::record(
        &state.pool,
        Some(user.id),
        "token.create",
        Some("network"),
        Some(&network.id.to_string()),
        None,
    )
    .await?;

    Ok(Json(response))
}

async fn revoke_token(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path(id): Path<Uuid>,
    Json(req): Json<RevokeTokenRequest>,
) -> Result<Json<EnrollmentToken>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_TOKENS_WRITE).await?;
    let (network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    let response = client
        .revoke_token(&req.token_id)
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;

    audit_log::record(
        &state.pool,
        Some(user.id),
        "token.revoke",
        Some("network"),
        Some(&network.id.to_string()),
        Some(serde_json::json!({ "token_id": req.token_id })),
    )
    .await?;

    Ok(Json(response))
}

async fn list_nodes(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path(id): Path<Uuid>,
) -> Result<Json<AdminNodesResponse>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_NODES_READ).await?;
    let (network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    let response = client
        .list_nodes(&network.network_id)
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;
    Ok(Json(response))
}

async fn approve_node(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path((id, node_id)): Path<(Uuid, String)>,
) -> Result<Json<crate::control_plane::ApproveNodeResponse>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_NODES_WRITE).await?;
    let (_network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    let response = client
        .approve_node(&node_id)
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;

    audit_log::record(
        &state.pool,
        Some(user.id),
        "node.approve",
        Some("node"),
        Some(&node_id),
        None,
    )
    .await?;

    Ok(Json(response))
}

async fn revoke_node(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path((id, node_id)): Path<(Uuid, String)>,
) -> Result<Json<crate::control_plane::RevokeNodeResponse>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_NODES_WRITE).await?;
    let (_network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    let response = client
        .revoke_node(&node_id)
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;

    audit_log::record(
        &state.pool,
        Some(user.id),
        "node.revoke",
        Some("node"),
        Some(&node_id),
        None,
    )
    .await?;

    Ok(Json(response))
}

async fn rotate_keys(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path((id, node_id)): Path<(Uuid, String)>,
    Json(req): Json<RotateKeysRequest>,
) -> Result<Json<KeyRotationResponse>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_NODES_WRITE).await?;
    let (_network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    let response = client
        .rotate_keys(
            &node_id,
            KeyRotationRequest {
                machine_public_key: req.machine_public_key,
                wg_public_key: req.wg_public_key,
            },
        )
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;

    audit_log::record(
        &state.pool,
        Some(user.id),
        "node.rotate_keys",
        Some("node"),
        Some(&node_id),
        None,
    )
    .await?;

    Ok(Json(response))
}

async fn node_keys(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path((id, node_id)): Path<(Uuid, String)>,
) -> Result<Json<KeyHistoryResponse>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_NODES_READ).await?;
    let (_network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    let response = client
        .node_keys(&node_id)
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;
    Ok(Json(response))
}

async fn get_acl(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path(id): Path<Uuid>,
) -> Result<Json<Value>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_ACL_READ).await?;
    let (network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    let response = client
        .get_acl(&network.network_id)
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;
    Ok(Json(response))
}

async fn update_acl(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path(id): Path<Uuid>,
    Json(req): Json<UpdateAclRequest>,
) -> Result<Json<Value>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_ACL_WRITE).await?;
    let (network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    let response = client
        .update_acl(&network.network_id, req.policy)
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;

    audit_log::record(
        &state.pool,
        Some(user.id),
        "network.update_acl",
        Some("network"),
        Some(&network.id.to_string()),
        None,
    )
    .await?;

    Ok(Json(response))
}

async fn get_key_policy(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path(id): Path<Uuid>,
) -> Result<Json<KeyPolicyResponse>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_KEY_POLICY_READ).await?;
    let (network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    let response = client
        .get_key_policy(&network.network_id)
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;
    Ok(Json(response))
}

async fn update_key_policy(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path(id): Path<Uuid>,
    Json(req): Json<KeyRotationPolicy>,
) -> Result<Json<KeyPolicyResponse>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_KEY_POLICY_WRITE).await?;
    let (network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    let response = client
        .update_key_policy(&network.network_id, req)
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;

    audit_log::record(
        &state.pool,
        Some(user.id),
        "network.update_key_policy",
        Some("network"),
        Some(&network.id.to_string()),
        None,
    )
    .await?;

    Ok(Json(response))
}

async fn network_audit(
    State(state): State<crate::app_state::AppState>,
    AuthUser { user }: AuthUser,
    Path(id): Path<Uuid>,
    Query(query): Query<NetworkAuditQuery>,
) -> Result<Json<crate::control_plane::AuditLogResponse>, ApiError> {
    ensure_permission_global(&state.pool, &user, PERM_AUDIT_READ).await?;
    let (network, control_plane) = fetch_network_with_cp(&state.pool, id).await?;
    let client = client_for(&control_plane);
    let response = client
        .audit_log(crate::control_plane::AuditLogQuery {
            network_id: Some(network.network_id),
            node_id: query.node_id,
            limit: query.limit,
        })
        .await
        .map_err(|_| ApiError::BadRequest("control plane request failed".to_string()))?;
    Ok(Json(response))
}

#[derive(sqlx::FromRow)]
struct NetworkRow {
    id: Uuid,
    control_plane_id: Uuid,
    control_plane_name: String,
    network_id: String,
    name: String,
    dns_domain: Option<String>,
    overlay_v4: Option<String>,
    overlay_v6: Option<String>,
    requires_approval: bool,
    created_at: OffsetDateTime,
    updated_at: OffsetDateTime,
}

async fn fetch_network_summary(pool: &PgPool, id: Uuid) -> Result<NetworkRow, ApiError> {
    sqlx::query_as::<_, NetworkRow>(
        r#"
        SELECT n.id,
               n.control_plane_id,
               n.network_id,
               n.name,
               n.dns_domain,
               n.overlay_v4,
               n.overlay_v6,
               n.requires_approval,
               n.created_at,
               n.updated_at,
               c.name AS control_plane_name
        FROM networks n
        JOIN control_planes c ON c.id = n.control_plane_id
        WHERE n.id = $1
        "#,
    )
    .bind(id)
    .fetch_optional(pool)
    .await
    .map_err(|_| ApiError::Internal)?
    .ok_or(ApiError::NotFound)
}

async fn fetch_network_with_cp(
    pool: &PgPool,
    network_id: Uuid,
) -> Result<(Network, ControlPlane), ApiError> {
    let network = sqlx::query_as::<_, Network>(
        r#"
        SELECT id, control_plane_id, network_id, name, dns_domain, overlay_v4, overlay_v6,
               requires_approval, created_at, updated_at
        FROM networks
        WHERE id = $1
        "#,
    )
    .bind(network_id)
    .fetch_optional(pool)
    .await
    .map_err(|_| ApiError::Internal)?
    .ok_or(ApiError::NotFound)?;

    let control_plane = fetch_control_plane(pool, network.control_plane_id).await?;
    Ok((network, control_plane))
}

async fn fetch_control_plane(pool: &PgPool, id: Uuid) -> Result<ControlPlane, ApiError> {
    sqlx::query_as::<_, ControlPlane>(
        r#"
        SELECT id, name, base_url, admin_token, region, created_at, updated_at
        FROM control_planes
        WHERE id = $1
        "#,
    )
    .bind(id)
    .fetch_optional(pool)
    .await
    .map_err(|_| ApiError::Internal)?
    .ok_or(ApiError::NotFound)
}

async fn insert_network(
    pool: &PgPool,
    control_plane: &ControlPlane,
    network: &NetworkInfo,
    dns_override: Option<String>,
) -> Result<Network, ApiError> {
    let now = OffsetDateTime::now_utc();
    sqlx::query_as::<_, Network>(
        r#"
        INSERT INTO networks (
            id, control_plane_id, network_id, name, dns_domain, overlay_v4, overlay_v6,
            requires_approval, created_at, updated_at
        )
        VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $9)
        RETURNING id, control_plane_id, network_id, name, dns_domain, overlay_v4, overlay_v6,
                  requires_approval, created_at, updated_at
        "#,
    )
    .bind(Uuid::new_v4())
    .bind(control_plane.id)
    .bind(&network.id)
    .bind(&network.name)
    .bind(dns_override.or_else(|| Some(network.dns_domain.clone())))
    .bind(&network.overlay_v4)
    .bind(&network.overlay_v6)
    .bind(network.requires_approval)
    .bind(now)
    .fetch_one(pool)
    .await
    .map_err(|_| ApiError::Internal)
}

fn client_for(control_plane: &ControlPlane) -> crate::control_plane::ControlPlaneClient {
    crate::control_plane::ControlPlaneClient::new(
        control_plane.base_url.clone(),
        control_plane.admin_token.clone(),
    )
}