import type { ModelType, PredictionClass } from "../context/AnalysisContext";

export interface ConfidenceScores {
  Healthy: number;
  MCI: number;
  AD: number;
}

export interface FoldPrediction {
  fold: number;
  prediction: PredictionClass;
  confidence: number;
  confidence_scores: ConfidenceScores;
}

export interface AnalyzeResponse {
  id: string;
  file_name: string;
  model: Exclude<ModelType, null>;
  prediction: PredictionClass;
  confidence: number;
  confidence_scores: ConfidenceScores;
  processed_at: string;
  spectrogram_image: string | null;
  scalogram_montage_image: string | null;
  spectrogram_channels: (string | null)[];
  scalogram_channels: (string | null)[];
  channel_0_image: string | null;
  channel_1_image: string | null;
  mock: boolean;
  fold_predictions: FoldPrediction[];
  fold_vote_counts: Partial<Record<PredictionClass, number>>;
  ensemble_folds: number;
  ensemble_mode: string;
}

export interface TrialAnalysisResult {
  id: string;
  file_name: string;
  trial_no: number | null;
  prediction: PredictionClass;
  confidence: number;
  confidence_scores: ConfidenceScores;
  spectrogram_image: string | null;
  scalogram_montage_image: string | null;
  spectrogram_channels: (string | null)[];
  scalogram_channels: (string | null)[];
  mock: boolean;
  fold_predictions: FoldPrediction[];
  fold_vote_counts: Partial<Record<PredictionClass, number>>;
  ensemble_folds: number;
  ensemble_mode: string;
}

export interface PatientAnalyzeResponse {
  id: string;
  patient_id: string;
  model: Exclude<ModelType, null>;
  prediction: PredictionClass;
  confidence: number;
  confidence_scores: ConfidenceScores;
  vote_counts: Partial<Record<PredictionClass, number>>;
  trial_count: number;
  agreement_ratio: number;
  processed_at: string;
  trial_results: TrialAnalysisResult[];
  mock: boolean;
}

const API_BASE = import.meta.env.VITE_API_URL ?? "";

export class AnalysisApiError extends Error {
  constructor(
    message: string,
    public status?: number,
  ) {
    super(message);
    this.name = "AnalysisApiError";
  }
}

export async function analyzeEeg(file: File, model: Exclude<ModelType, null>): Promise<AnalyzeResponse> {
  const formData = new FormData();
  formData.append("file", file);
  formData.append("model", model);

  const response = await fetch(`${API_BASE}/api/analyze`, {
    method: "POST",
    body: formData,
  });

  if (!response.ok) {
    let detail = "Analysis request failed.";
    try {
      const body = await response.json();
      if (typeof body.detail === "string") {
        detail = body.detail;
      } else if (Array.isArray(body.detail)) {
        detail = body.detail.map((d: { msg?: string }) => d.msg).filter(Boolean).join(", ") || detail;
      }
    } catch {
      if (response.status === 500) {
        detail = "Server error — ensure the backend is running and USE_MOCK_INFERENCE=true in backend/.env";
      }
    }
    throw new AnalysisApiError(detail, response.status);
  }

  return response.json();
}

export async function analyzePatientEeg(
  files: File[],
  model: Exclude<ModelType, null>,
): Promise<PatientAnalyzeResponse> {
  const formData = new FormData();
  files.forEach((file) => formData.append("files", file));
  formData.append("model", model);

  const response = await fetch(`${API_BASE}/api/analyze/patient`, {
    method: "POST",
    body: formData,
  });

  if (!response.ok) {
    let detail = "Patient analysis request failed.";
    try {
      const body = await response.json();
      if (typeof body.detail === "string") {
        detail = body.detail;
      } else if (Array.isArray(body.detail)) {
        detail = body.detail.map((d: { msg?: string }) => d.msg).filter(Boolean).join(", ") || detail;
      }
    } catch {
      if (response.status === 404) {
        detail = "Patient endpoint not found — restart the backend (npm run dev:backend).";
      } else if (response.status === 500) {
        detail = "Server error — restart the backend and try again.";
      }
    }
    throw new AnalysisApiError(detail, response.status);
  }

  return response.json();
}

export async function checkApiHealth(): Promise<boolean> {
  try {
    const response = await fetch(`${API_BASE}/api/health`);
    return response.ok;
  } catch {
    return false;
  }
}

export interface ModelStatusItem {
  name: Exclude<ModelType, null>;
  loaded: boolean;
  weights_found: boolean;
  weights_path: string;
}

export interface ModelsStatusResponse {
  models: ModelStatusItem[];
  use_mock_inference: boolean;
  fusion_detail: Record<string, unknown> | null;
}

export async function fetchModelsStatus(): Promise<ModelsStatusResponse | null> {
  try {
    const response = await fetch(`${API_BASE}/api/models/status`);
    if (!response.ok) return null;
    return response.json();
  } catch {
    return null;
  }
}