/**
 * Cases domain hooks.
 *
 * Note on types: the FastAPI `/api/cases` endpoint doesn't declare a response
 * model, so openapi-typescript emits `unknown` for its payload. Until the
 * backend is annotated (see out-of-scope in the rewrite plan), we maintain a
 * small local type that matches what the running API returns today. Any drift
 * surfaces as a runtime TypeScript error the first time a property is touched.
 */

import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
import { apiRequest } from "./client";
import type { CaseCreateInput, CaseUpdateInput } from "@/lib/schemas/case";
import type { PracticeArea, AppealSubtype } from "@/lib/practice-area";

export type CaseStatus =
  | "new"
  | "uploading"
  | "processing"
  | "documents_ready"
  | "analyst_verified"
  | "research_complete"
  | "outcome_set"
  | "brainstorming"
  | "direction_approved"
  | "analysis_enriched"
  | "ready_for_writing"
  | "drafting"
  | "qa_review"
  | "drafted"
  | "exported"
  | "reviewed"
  | "final";

export type Case = {
  case_number: string;
  title: string;
  status: CaseStatus;
  subject?: string | null;
  expected_outcome?: string | null;
  created_at?: string;
  updated_at?: string;
  /* Multi-tenant axis — populated by backfill + server-side derive */
  practice_area?: PracticeArea;
  appeal_subtype?: AppealSubtype;
  /* Present when loaded with detail=true */
  document_count?: number;
  processing_count?: number;
  committee_type?: string | null;
  hearing_date?: string | null;
};

export type CaseDocument = {
  id: string;
  case_id: string;
  doc_type: string;
  title: string;
  file_path: string;
  page_count: number | null;
  extraction_status: string;
  created_at: string;
  practice_area?: PracticeArea;
  appeal_subtype?: AppealSubtype;
};

export type CaseDetail = Case & {
  documents?: CaseDocument[];
  blocks?: Array<{ code: string; status?: string; char_count?: number }>;
};

export const casesKeys = {
  all: ["cases"] as const,
  list: (detail: boolean) => [...casesKeys.all, "list", { detail }] as const,
  detail: (caseNumber: string) =>
    [...casesKeys.all, "detail", caseNumber] as const,
};

export function useCases(detail = false) {
  return useQuery({
    queryKey: casesKeys.list(detail),
    queryFn: ({ signal }) =>
      apiRequest<Case[]>(`/api/cases${detail ? "?detail=true" : ""}`, {
        signal,
      }),
  });
}

export function useCase(caseNumber: string | undefined) {
  return useQuery({
    queryKey: casesKeys.detail(caseNumber ?? ""),
    queryFn: ({ signal }) =>
      apiRequest<CaseDetail>(`/api/cases/${caseNumber}/details`, { signal }),
    enabled: Boolean(caseNumber),
    /* Replaces the old 5s polling from vanilla index.html */
    staleTime: 5_000,
    refetchInterval: 5_000,
  });
}

export type WorkflowStatus = {
  case_number?: string;
  status?: CaseStatus | string;
  current_step?: string;
  steps?: Array<{
    key: string;
    label?: string;
    status: "done" | "current" | "pending" | string;
  }>;
  /* FastAPI returns free-form JSON; keep it permissive */
  [key: string]: unknown;
};

export function useCreateCase() {
  const qc = useQueryClient();
  return useMutation({
    mutationFn: (input: CaseCreateInput) =>
      apiRequest<{ case_number?: string; message?: string; [k: string]: unknown }>(
        `/api/cases/create`,
        { method: "POST", body: input },
      ),
    onSuccess: () => {
      qc.invalidateQueries({ queryKey: casesKeys.all });
    },
  });
}

export function useUpdateCase(caseNumber: string | undefined) {
  const qc = useQueryClient();
  return useMutation({
    mutationFn: (input: CaseUpdateInput) =>
      apiRequest<CaseDetail>(`/api/cases/${caseNumber}`, {
        method: "PUT",
        body: input,
      }),
    onSuccess: (data) => {
      /* Patch cached detail and nudge the list to refetch on next focus */
      if (caseNumber) {
        qc.setQueryData<CaseDetail | undefined>(
          casesKeys.detail(caseNumber),
          (prev) => (prev ? { ...prev, ...data } : prev),
        );
      }
      qc.invalidateQueries({ queryKey: casesKeys.all });
    },
  });
}

export type GitSyncStatus = {
  synced: boolean;
  has_remote: boolean;
  remote_url?: string | null;
  dirty_files: number;
  commits_ahead: number;
  last_commit_time?: string | null;
  last_commit_msg?: string | null;
  error?: string;
};

export function useGitStatus(caseNumber: string | undefined) {
  return useQuery({
    queryKey: [...casesKeys.all, "git-status", caseNumber ?? ""] as const,
    queryFn: ({ signal }) =>
      apiRequest<GitSyncStatus>(`/api/cases/${caseNumber}/git-status`, { signal }),
    enabled: Boolean(caseNumber),
    staleTime: 30_000,
    refetchInterval: 60_000,
  });
}

export type StartWorkflowResult = {
  case_number: string;
  status: string;
  issue_id: string;
  issue_identifier: string;
  project_url: string;
  wakeup: Record<string, unknown>;
};

export function useStartWorkflow(caseNumber: string | undefined) {
  const qc = useQueryClient();
  return useMutation({
    mutationFn: () =>
      apiRequest<StartWorkflowResult>(
        `/api/cases/${caseNumber}/start-workflow`,
        { method: "POST" },
      ),
    onSuccess: () => {
      qc.invalidateQueries({ queryKey: casesKeys.all });
      if (caseNumber) {
        qc.invalidateQueries({ queryKey: casesKeys.detail(caseNumber) });
      }
    },
  });
}

export function useWorkflowStatus(caseNumber: string | undefined) {
  return useQuery({
    queryKey: [...casesKeys.all, "workflow", caseNumber ?? ""] as const,
    queryFn: ({ signal }) =>
      apiRequest<WorkflowStatus>(`/api/cases/${caseNumber}/status`, { signal }),
    enabled: Boolean(caseNumber),
    staleTime: 5_000,
    refetchInterval: 5_000,
  });
}