const API = process.env.NEXT_PUBLIC_API_BASE_URL ?? "http://localhost:9812";

export type StructuredBlock = {
    path: string;
    block_type: string;
    text: string;
    keywords: string[];
};

export type Patch = {
    id: string;
    target_path: string;
    operation: string;
    old_value?: string | null;
    new_value?: string | null;
    metadata_json?: Record<string, unknown> | null;
    created_at: string;
};

export type Version = {
    id: string;
    branch_name: string;
    version_label?: string | null;
    parent_version_id?: string | null;
    structured_blocks?: StructuredBlock[] | null;
    artifact_docx_key?: string | null;
    patches: Patch[];
    created_at: string;
    updated_at: string;
};

export type Document = {
    id: string;
    title: string;
    description?: string | null;
    owner_id: string;
    root_version_id?: string | null;
    versions: Version[];
    created_at: string;
    updated_at: string;
};

export type Submission = {
    id: string;
    version_id: string;
    company_name: string;
    role_title: string;
    job_url?: string | null;
    job_description?: string | null;
    status: string;
    created_at: string;
};

export type PublicAsset = {
    id: string;
    slug: string;
    artifact_key: string;
    is_public: boolean;
    url?: string | null;
    version_id?: string | null;
    submission_id?: string | null;
    created_at: string;
};

async function req<T>(path: string, init?: RequestInit): Promise<T> {
    const res = await fetch(`${API}${path}`, {
        ...init,
        headers: { accept: "application/json", ...init?.headers },
    });
    if (!res.ok) {
        const detail = await res.text().catch(() => res.statusText);
        throw new Error(detail || `HTTP ${res.status}`);
    }
    return res.json();
}

export const fetchDocuments = (): Promise<Document[]> =>
    req<{ items: Document[] }>("/api/v1/documents", { cache: "no-store" }).then(r => r.items);

export const fetchDocument = (id: string): Promise<Document> =>
    req<Document>(`/api/v1/documents/${id}`, { cache: "no-store" });

export async function uploadDocument(title: string, description: string | null, file: File): Promise<Document> {
    const form = new FormData();
    form.append("title", title);
    if (description) form.append("description", description);
    form.append("file", file);
    return req<Document>("/api/v1/documents", { method: "POST", body: form });
}

export const downloadVersionUrl = (documentId: string, versionId: string): string =>
    `${API}/api/v1/documents/${documentId}/versions/${versionId}/download`;

export async function createBranch(
    parentVersionId: string,
    branchName: string,
    versionLabel?: string | null,
    patches: Record<string, unknown>[] = [],
): Promise<Version> {
    return req<Version>("/api/v1/versions/branches", {
        method: "POST",
        headers: { "content-type": "application/json" },
        body: JSON.stringify({ parent_version_id: parentVersionId, branch_name: branchName, version_label: versionLabel ?? null, patches }),
    });
}

export async function createSubmission(
    versionId: string,
    companyName: string,
    roleTitle: string,
    jobUrl?: string | null,
    jobDescription?: string | null,
): Promise<Submission> {
    return req<Submission>("/api/v1/submissions", {
        method: "POST",
        headers: { "content-type": "application/json" },
        body: JSON.stringify({ version_id: versionId, company_name: companyName, role_title: roleTitle, job_url: jobUrl ?? null, job_description: jobDescription ?? null }),
    });
}

export async function publishVersion(
    versionId?: string | null,
    submissionId?: string | null,
    slug?: string | null,
): Promise<PublicAsset> {
    return req<PublicAsset>("/api/v1/public/publish", {
        method: "POST",
        headers: { "content-type": "application/json" },
        body: JSON.stringify({ version_id: versionId ?? null, submission_id: submissionId ?? null, slug: slug ?? null }),
    });
}

export { API as API_BASE_URL };