use crate::{errors::AppError, extractors::JwtClaims, state::AppState};
use api_types::{
    requests::UpdateMetadataRequest,
    responses::{AssetResponse, IngestResponse, TimelineResponse},
};
use application::{
    catalog::{GetAssetQuery, GetTimelineQuery, UpdateMetadataCommand},
    storage::IngestAssetCommand,
};
use axum::{
    Json,
    extract::{Multipart, Path, Query, State},
    http::StatusCode,
};
use domain::value_objects::{MetadataValue, StructuredData, SystemId};
use sha2::{Digest, Sha256};

#[derive(Debug, serde::Deserialize)]
pub struct TimelineParams {
    pub limit: Option<u32>,
    pub offset: Option<u32>,
}

pub async fn ingest(
    State(state): State<AppState>,
    claims: JwtClaims,
    mut multipart: Multipart,
) -> Result<(StatusCode, Json<IngestResponse>), AppError> {
    let mut file_data: Option<bytes::Bytes> = None;
    let mut filename: Option<String> = None;
    let mut target_path_id: Option<uuid::Uuid> = None;
    let mut client_device_id = "web".to_string();

    while let Some(field) = multipart
        .next_field()
        .await
        .map_err(|e| AppError::from(domain::errors::DomainError::Validation(e.to_string())))?
    {
        let name = field.name().unwrap_or("").to_string();
        match name.as_str() {
            "file" => {
                filename = field.file_name().map(|s| s.to_string());
                let data = field
                    .bytes()
                    .await
                    .map_err(|e| {
                        AppError::from(domain::errors::DomainError::Internal(e.to_string()))
                    })?;
                file_data = Some(data);
            }
            "target_path_id" => {
                let text = field
                    .text()
                    .await
                    .map_err(|e| {
                        AppError::from(domain::errors::DomainError::Validation(e.to_string()))
                    })?;
                target_path_id = Some(text.parse::<uuid::Uuid>().map_err(|e| {
                    AppError::from(domain::errors::DomainError::Validation(e.to_string()))
                })?);
            }
            "client_device_id" => {
                client_device_id = field
                    .text()
                    .await
                    .map_err(|e| {
                        AppError::from(domain::errors::DomainError::Validation(e.to_string()))
                    })?;
            }
            _ => {}
        }
    }

    let data = file_data
        .ok_or_else(|| AppError::from(domain::errors::DomainError::Validation("Missing file field".to_string())))?;
    let fname = filename
        .ok_or_else(|| AppError::from(domain::errors::DomainError::Validation("Missing filename".to_string())))?;
    let path_id = target_path_id
        .ok_or_else(|| AppError::from(domain::errors::DomainError::Validation("Missing target_path_id".to_string())))?;

    let mut hasher = Sha256::new();
    hasher.update(&data);
    let checksum = format!("{:x}", hasher.finalize());

    let file_size = data.len() as u64;

    let cmd = IngestAssetCommand {
        uploader_id: claims.user_id,
        client_device_id,
        filename: fname,
        checksum,
        target_path_id: SystemId::from_uuid(path_id),
        file_size,
        data,
    };

    let (asset, session) = state.ingest_asset_handler.execute(cmd).await?;
    let empty_meta = StructuredData::new();

    Ok((
        StatusCode::CREATED,
        Json(IngestResponse {
            asset: AssetResponse::from_domain(&asset, &empty_meta),
            session_id: *session.session_id.as_uuid(),
        }),
    ))
}

pub async fn get_asset(
    State(state): State<AppState>,
    _claims: JwtClaims,
    Path((asset_id,)): Path<(uuid::Uuid,)>,
) -> Result<Json<AssetResponse>, AppError> {
    let query = GetAssetQuery {
        asset_id: SystemId::from_uuid(asset_id),
    };
    let (asset, metadata) = state.get_asset_handler.execute(query).await?;
    Ok(Json(AssetResponse::from_domain(&asset, &metadata)))
}

pub async fn timeline(
    State(state): State<AppState>,
    claims: JwtClaims,
    Query(params): Query<TimelineParams>,
) -> Result<Json<TimelineResponse>, AppError> {
    let query = GetTimelineQuery {
        owner_id: claims.user_id,
        limit: params.limit.unwrap_or(50),
        offset: params.offset.unwrap_or(0),
    };
    let results = state.get_timeline_handler.execute(query).await?;
    let total = results.len();
    let assets = results
        .iter()
        .map(|(asset, meta)| AssetResponse::from_domain(asset, meta))
        .collect();
    Ok(Json(TimelineResponse { assets, total }))
}

pub async fn update_metadata(
    State(state): State<AppState>,
    claims: JwtClaims,
    Path((asset_id,)): Path<(uuid::Uuid,)>,
    Json(req): Json<UpdateMetadataRequest>,
) -> Result<Json<serde_json::Value>, AppError> {
    let mut data = StructuredData::new();
    for (k, v) in req.data {
        let mv = match v {
            serde_json::Value::String(s) => MetadataValue::String(s),
            serde_json::Value::Number(n) => {
                if let Some(i) = n.as_i64() {
                    MetadataValue::Integer(i)
                } else if let Some(f) = n.as_f64() {
                    MetadataValue::Float(f)
                } else {
                    MetadataValue::Null
                }
            }
            serde_json::Value::Bool(b) => MetadataValue::Boolean(b),
            serde_json::Value::Null => MetadataValue::Null,
            _ => MetadataValue::String(v.to_string()),
        };
        data.insert(k, mv);
    }

    let cmd = UpdateMetadataCommand {
        asset_id: SystemId::from_uuid(asset_id),
        user_id: claims.user_id,
        data,
    };
    state.update_metadata_handler.execute(cmd).await?;
    Ok(Json(serde_json::json!({ "status": "updated" })))
}