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

use crate::api::response::{ApiErrorResponse, ApiResponse};
use crate::error::AppError;
use crate::models::base_info;
use crate::models::base_info::UserBaseInfo;
use crate::models::prs::{PrReviewComment, PrReviewDetail};
use crate::service::AppService;
use crate::service::pr::reviews::{
    AddReplyParams, CreateReviewParams, DismissReviewParams, SubmitReviewParams,
};
use crate::session::Session;

#[derive(Debug, Deserialize, IntoParams)]
pub struct PrPath {
    /// 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,
}

#[derive(Debug, Deserialize, IntoParams)]
pub struct ReviewPath {
    /// 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,
    /// Review ID (UUID)
    pub review_id: uuid::Uuid,
}

#[derive(Debug, Deserialize, IntoParams)]
pub struct CommentPath {
    /// 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,
    /// Comment ID (UUID)
    pub comment_id: uuid::Uuid,
}

#[derive(Debug, Deserialize, IntoParams)]
pub struct QP {
    pub limit: Option<i64>,
    pub offset: Option<i64>,
}

/// List reviews on a PR
#[utoipa::path(
    get,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/reviews",
    tag = "Pull Requests",
    operation_id = "prListReviews",
    params(PrPath, QP),
    responses(
        (status = 200, description = "Reviews listed.", body = ApiResponse<Vec<PrReviewDetail>>),
        (status = 401, description = "Authentication required", body = ApiErrorResponse),
        (status = 404, description = "PR not found", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(("session_cookie" = []))
)]
pub async fn list_reviews(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<PrPath>,
    query: web::Query<QP>,
) -> Result<HttpResponse, AppError> {
    let reviews = service
        .pr
        .pr_list_reviews(
            &session,
            &path.workspace_name,
            &path.repo_name,
            path.number,
            query.limit.unwrap_or(50),
            query.offset.unwrap_or(0),
        )
        .await?;
    let user_ids: Vec<_> = reviews.iter().map(|r| r.author_id).collect();
    let users = base_info::resolve_users(&service.ctx.db, &user_ids).await?;
    let details: Vec<PrReviewDetail> = reviews
        .into_iter()
        .map(|r| {
            let author = users
                .get(&r.author_id)
                .cloned()
                .unwrap_or_else(|| UserBaseInfo::placeholder(r.author_id));
            r.into_detail(author)
        })
        .collect();
    Ok(HttpResponse::Ok().json(ApiResponse::new(details)))
}

/// Create a review. States: pending, approved, changes_requested, commented. Authors cannot approve their own PRs.
#[utoipa::path(
    post,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/reviews",
    tag = "Pull Requests",
    operation_id = "prCreateReview",
    params(PrPath),
    request_body(content = CreateReviewParams, description = "Review parameters", content_type = "application/json"),
    responses(
        (status = 201, description = "Review created.", body = ApiResponse<PrReviewDetail>),
        (status = 400, description = "Invalid state or self-approval", body = ApiErrorResponse),
        (status = 401, description = "Authentication required", 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 create_review(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<PrPath>,
    params: web::Json<CreateReviewParams>,
) -> Result<HttpResponse, AppError> {
    let review = service
        .pr
        .pr_create_review(
            &session,
            &path.workspace_name,
            &path.repo_name,
            path.number,
            params.into_inner(),
        )
        .await?;
    let author_id = review.author_id;
    let users = base_info::resolve_users(&service.ctx.db, &[author_id]).await?;
    let author = users
        .get(&author_id)
        .cloned()
        .unwrap_or_else(|| UserBaseInfo::placeholder(author_id));
    Ok(HttpResponse::Created().json(ApiResponse::new(review.into_detail(author))))
}

/// Submit a pending review. Changes its state to approved, changes_requested, or commented.
#[utoipa::path(
    post,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/reviews/{review_id}/submit",
    tag = "Pull Requests",
    operation_id = "prSubmitReview",
    params(ReviewPath),
    request_body(content = SubmitReviewParams, description = "Submit parameters", content_type = "application/json"),
    responses(
        (status = 200, description = "Review submitted.", body = ApiResponse<PrReviewDetail>),
        (status = 400, description = "Invalid state or self-approval", body = ApiErrorResponse),
        (status = 401, description = "Authentication required", body = ApiErrorResponse),
        (status = 403, description = "Insufficient permissions", body = ApiErrorResponse),
        (status = 404, description = "Review not found or already submitted", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(("session_cookie" = []))
)]
pub async fn submit_review(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<ReviewPath>,
    params: web::Json<SubmitReviewParams>,
) -> Result<HttpResponse, AppError> {
    let review = service
        .pr
        .pr_submit_review(
            &session,
            &path.workspace_name,
            &path.repo_name,
            path.number,
            path.review_id,
            params.into_inner(),
        )
        .await?;
    let author_id = review.author_id;
    let users = base_info::resolve_users(&service.ctx.db, &[author_id]).await?;
    let author = users
        .get(&author_id)
        .cloned()
        .unwrap_or_else(|| UserBaseInfo::placeholder(author_id));
    Ok(HttpResponse::Ok().json(ApiResponse::new(review.into_detail(author))))
}

/// Dismiss a submitted review. Requires Admin role.
#[utoipa::path(
    post,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/reviews/{review_id}/dismiss",
    tag = "Pull Requests",
    operation_id = "prDismissReview",
    params(ReviewPath),
    request_body(content = DismissReviewParams, description = "Dismiss parameters", content_type = "application/json"),
    responses(
        (status = 200, description = "Review dismissed.", body = ApiResponse<PrReviewDetail>),
        (status = 401, description = "Authentication required", body = ApiErrorResponse),
        (status = 403, description = "Insufficient permissions (Admin required)", body = ApiErrorResponse),
        (status = 404, description = "Review not found or not submitted", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(("session_cookie" = []))
)]
pub async fn dismiss_review(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<ReviewPath>,
    params: web::Json<DismissReviewParams>,
) -> Result<HttpResponse, AppError> {
    let review = service
        .pr
        .pr_dismiss_review(
            &session,
            &path.workspace_name,
            &path.repo_name,
            path.number,
            path.review_id,
            params.into_inner(),
        )
        .await?;
    let author_id = review.author_id;
    let users = base_info::resolve_users(&service.ctx.db, &[author_id]).await?;
    let author = users
        .get(&author_id)
        .cloned()
        .unwrap_or_else(|| UserBaseInfo::placeholder(author_id));
    Ok(HttpResponse::Ok().json(ApiResponse::new(review.into_detail(author))))
}

/// List comments for a specific review
#[utoipa::path(
    get,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/reviews/{review_id}/comments",
    tag = "Pull Requests",
    operation_id = "prListReviewComments",
    params(ReviewPath, QP),
    responses(
        (status = 200, description = "Review comments listed.", body = ApiResponse<Vec<PrReviewComment>>),
        (status = 401, description = "Authentication required", body = ApiErrorResponse),
        (status = 404, description = "Review not found", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(("session_cookie" = []))
)]
pub async fn list_review_comments(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<ReviewPath>,
    query: web::Query<QP>,
) -> Result<HttpResponse, AppError> {
    let comments = service
        .pr
        .pr_review_comments(
            &session,
            &path.workspace_name,
            &path.repo_name,
            path.number,
            path.review_id,
            query.limit.unwrap_or(50),
            query.offset.unwrap_or(0),
        )
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new(comments)))
}

/// Reply to a review comment
#[utoipa::path(
    post,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/comments/{comment_id}/reply",
    tag = "Pull Requests",
    operation_id = "prAddReviewReply",
    params(CommentPath),
    request_body(content = AddReplyParams, description = "Reply parameters", content_type = "application/json"),
    responses(
        (status = 201, description = "Reply added.", body = ApiResponse<PrReviewComment>),
        (status = 400, description = "Empty body", body = ApiErrorResponse),
        (status = 401, description = "Authentication required", body = ApiErrorResponse),
        (status = 404, description = "Comment not found", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(("session_cookie" = []))
)]
pub async fn add_review_reply(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<CommentPath>,
    params: web::Json<AddReplyParams>,
) -> Result<HttpResponse, AppError> {
    let comment = service
        .pr
        .pr_add_review_reply(
            &session,
            &path.workspace_name,
            &path.repo_name,
            path.number,
            path.comment_id,
            params.into_inner(),
        )
        .await?;
    Ok(HttpResponse::Created().json(ApiResponse::new(comment)))
}

/// Update a review comment (own comments only)
#[utoipa::path(
    put,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/comments/{comment_id}",
    tag = "Pull Requests",
    operation_id = "prUpdateReviewComment",
    params(CommentPath),
    request_body(content = AddReplyParams, description = "Update parameters", content_type = "application/json"),
    responses(
        (status = 200, description = "Comment updated.", body = ApiResponse<PrReviewComment>),
        (status = 401, description = "Authentication required", body = ApiErrorResponse),
        (status = 403, description = "Cannot edit other users' comments", body = ApiErrorResponse),
        (status = 404, description = "Comment not found", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(("session_cookie" = []))
)]
pub async fn update_review_comment(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<CommentPath>,
    params: web::Json<AddReplyParams>,
) -> Result<HttpResponse, AppError> {
    let comment = service
        .pr
        .pr_update_review_comment(
            &session,
            &path.workspace_name,
            &path.repo_name,
            path.number,
            path.comment_id,
            params.into_inner(),
        )
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new(comment)))
}

/// Delete a review comment. Own comments or Admin role.
#[utoipa::path(
    delete,
    path = "/api/v1/workspaces/{workspace_name}/repos/{repo_name}/prs/{number}/comments/{comment_id}",
    tag = "Pull Requests",
    operation_id = "prDeleteReviewComment",
    params(CommentPath),
    responses(
        (status = 200, description = "Comment deleted.", body = ApiResponse<String>),
        (status = 401, description = "Authentication required", body = ApiErrorResponse),
        (status = 403, description = "Cannot delete other users' comments (Admin required)", body = ApiErrorResponse),
        (status = 404, description = "Comment not found", body = ApiErrorResponse),
        (status = 500, description = "Internal server error", body = ApiErrorResponse),
    ),
    security(("session_cookie" = []))
)]
pub async fn delete_review_comment(
    service: web::Data<AppService>,
    session: Session,
    path: web::Path<CommentPath>,
) -> Result<HttpResponse, AppError> {
    service
        .pr
        .pr_delete_review_comment(
            &session,
            &path.workspace_name,
            &path.repo_name,
            path.number,
            path.comment_id,
        )
        .await?;
    Ok(HttpResponse::Ok().json(ApiResponse::new("Comment deleted".to_string())))
}