use actix_web::{web, HttpResponse};
use serde::Deserialize;
use utoipa::IntoParams;

use crate::api::response::{ApiResponse, ApiErrorResponse};
use crate::error::AppError;
use crate::models::prs::PrMergeStrategy;
use crate::service::pr::merge_strategy::UpdateMergeStrategyParams;
use crate::service::AppService;
use crate::session::Session;

#[derive(Debug, Deserialize, IntoParams)]
pub struct PathParams {
    /// Workspace name (unique identifier)
    pub workspace_name: String,
    /// Repository name (unique within the workspace)
    pub repo_name: String,
    /// PR number (unique within the repository)
    pub number: i64,
}

/// Get PR merge strategy
///
/// Returns the current merge strategy settings for a PR.
/// Requires read access to the repository.
#[utoipa::path(
    get,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/merge-strategy",
    tag = "Pull Requests",
    operation_id = "prGetMergeStrategy",
    params(PathParams),
    responses(
        (status = 200, description = "Merge strategy retrieved successfully.", body = ApiResponse<PrMergeStrategy>),
        (status = 401, description = "Authentication required or session expired", body = ApiErrorResponse),
        (status = 404, description = "PR or merge strategy not found", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(("session_cookie" = []))
)]
pub async fn get_merge_strategy(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<PathParams>,
) -> Result<HttpResponse, AppError> {
    let strategy = service
        .pr
        .pr_merge_strategy(&session, &path.workspace_name, &path.repo_name, path.number)
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new(strategy)))
}

/// Update PR merge strategy
///
/// Updates the merge strategy settings for a PR.
/// Requires write access to the PR.
///
/// Updatable fields:
/// - strategy: Merge strategy type ("merge", "squash", "rebase")
/// - auto_merge: Enable auto-merge when all checks pass
/// - squash_title: Custom title for squash merge
/// - squash_message: Custom message for squash merge
/// - delete_source_branch: Delete source branch after merge
/// - merge_when_checks_pass: Auto-merge when checks pass
///
/// All fields are optional; only provided fields are updated.
#[utoipa::path(
    put,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/merge-strategy",
    tag = "Pull Requests",
    operation_id = "prUpdateMergeStrategy",
    params(PathParams),
    request_body(
        content = UpdateMergeStrategyParams,
        description = "Merge strategy update parameters (all fields optional)",
        content_type = "application/json"
    ),
    responses(
        (status = 200, description = "Merge strategy updated successfully.", body = ApiResponse<PrMergeStrategy>),
        (status = 400, description = "Invalid parameters: unsupported strategy", body = ApiErrorResponse),
        (status = 401, description = "Authentication required or session expired", body = ApiErrorResponse),
        (status = 403, description = "Insufficient permissions", body = ApiErrorResponse),
        (status = 404, description = "PR not found", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(("session_cookie" = []))
)]
pub async fn update_merge_strategy(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<PathParams>,
    params: web::Json<UpdateMergeStrategyParams>,
) -> Result<HttpResponse, AppError> {
    let strategy = service
        .pr
        .pr_update_merge_strategy(&session, &path.workspace_name, &path.repo_name, path.number, params.into_inner())
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new(strategy)))
}