//
//  CVTemplateFetchService.swift
//  App for Indeed
//
//  Fetches CV template definitions from OpenAI (structured JSON) so the gallery
//  is not limited to the built-in static catalog. Falls back are handled by callers.
//

import Foundation

// MARK: - Public API

final class CVTemplateFetchService {
    static let shared = CVTemplateFetchService()

    private let endpoint = URL(string: "https://api.openai.com/v1/responses")!
    private let session = URLSession(configuration: .ephemeral)

    private init() {}

    private enum CVTemplateCatalogPrompt {
        static let instructions = """
        You are the CV template catalog service for a desktop résumé builder. Invent exactly 30 distinct, plausible template \
        records for job seekers. Each must have a unique `id` (kebab-case ASCII, e.g. "river-stone"), a display `name` (1–3 words), \
        and varied visual parameters so thumbnails differ. Spread entries across all five `family` values (six templates per family). \
        Use creative but professional names; do not copy real commercial template trademarks. \
        Vary `headline`, `accent`, `layoutType`, `sidebarSide`, `sidebarTinted`, and `sectionLabelStyle` across the set — do not repeat \
        the same six-tuple of those fields on consecutive rows. \
        Niche split for the in-app gallery: `modern` and `creative` families are shown under Design-Based (portfolio / UX / visual roles); \
        `minimal`, `professional`, and `executive` appear under Profession-Based (ATS-friendly / corporate / leadership). \
        Output must strictly match the JSON schema — no markdown or extra keys.
        """
        static func userInput(language: AppLanguage) -> String {
            """
            Generate the template catalog now. Exactly six entries per family: professional, modern, creative, minimal, executive. \
            Use both singleColumn and twoColumn layouts across the 30 rows. For twoColumn rows vary leading vs trailing sidebars and tinted true/false. \
            Keep modern and creative entries suitable for design-led résumés; keep minimal, professional, and executive suitable for traditional industries. \
            \(displayNameRule(for: language))
            """
        }

        /// English `name` values double as localization keys in the app; keep them ASCII words.
        static func displayNameRule(for language: AppLanguage) -> String {
            switch language {
            case .english:
                return "Each `name` must be 1–3 English words (ASCII letters and spaces only), e.g. \"Creative Cascade\"."
            case .chineseTraditional:
                return "Each `name` must be 1–3 English words (ASCII letters and spaces only) suitable as localization keys, e.g. \"Creative Cascade\" — do not use Chinese characters in `name`."
            case .chineseSimplified:
                return "Each `name` must be 1–3 English words (ASCII letters and spaces only) suitable as localization keys, e.g. \"Design Dynamo\" — do not use Chinese characters in `name`."
            case .arabic:
                return "Each `name` must be 1–3 English words (ASCII letters and spaces only) suitable as localization keys, e.g. \"UI Sculptor\" — do not use Arabic script in `name`."
            case .french:
                return "Each `name` must be 1–3 English words (ASCII letters and spaces only) suitable as localization keys, e.g. \"Creative Cascade\" — do not use French characters in `name`."
            }
        }
    }

    /// Loads templates from OpenAI (one automatic retry on transient network / parse failures).
    func fetchTemplates(
        language: AppLanguage = currentAppLanguage(),
        completion: @escaping (Result<[CVTemplate], Error>) -> Void
    ) {
        let apiKey = OpenAIConfiguration.apiKey
        guard OpenAIConfiguration.hasAPIKey else {
            completion(.failure(Self.missingKeyError))
            return
        }

        var request = URLRequest(url: endpoint)
        request.httpMethod = "POST"
        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
        request.setValue("Bearer \(apiKey)", forHTTPHeaderField: "Authorization")
        request.timeoutInterval = 60

        do {
            request.httpBody = try Self.encodeCatalogRequestBody(language: language)
        } catch {
            completion(.failure(error))
            return
        }

        session.dataTask(with: request) { data, response, error in
            Self.handleFetchData(
                data,
                response: response,
                error: error,
                language: language,
                attempt: 0,
                completion: completion
            )
        }.resume()
    }

    private static func encodeCatalogRequestBody(language: AppLanguage) throws -> Data {
        let payload = CVTemplateOpenAIRequest.catalogPayload(
            model: "gpt-4o-mini",
            instructions: CVTemplateCatalogPrompt.instructions,
            input: CVTemplateCatalogPrompt.userInput(language: language)
        )
        return try JSONEncoder().encode(payload)
    }

    private static func handleFetchData(
        _ data: Data?,
        response: URLResponse?,
        error: Error?,
        language: AppLanguage,
        attempt: Int,
        completion: @escaping (Result<[CVTemplate], Error>) -> Void
    ) {
        if let error {
            if attempt == 0 {
                DispatchQueue.global(qos: .utility).asyncAfter(deadline: .now() + 2.0) {
                    refetchSameRequest(language: language, attempt: 1, completion: completion)
                }
                return
            }
            completion(.failure(error))
            return
        }
        guard let data else {
            if attempt == 0 {
                DispatchQueue.global(qos: .utility).asyncAfter(deadline: .now() + 2.0) {
                    refetchSameRequest(language: language, attempt: 1, completion: completion)
                }
                return
            }
            completion(.failure(Self.emptyResponseError))
            return
        }
        if let http = response as? HTTPURLResponse, !(200...299).contains(http.statusCode) {
            if attempt == 0, (500...599).contains(http.statusCode) || http.statusCode == 429 {
                DispatchQueue.global(qos: .utility).asyncAfter(deadline: .now() + 2.5) {
                    refetchSameRequest(language: language, attempt: 1, completion: completion)
                }
                return
            }
            if let apiError = try? JSONDecoder().decode(OpenAITemplatesAPIErrorResponse.self, from: data) {
                completion(.failure(NSError(
                    domain: "CVTemplateFetchService",
                    code: http.statusCode,
                    userInfo: [NSLocalizedDescriptionKey: apiError.error.message]
                )))
            } else {
                completion(.failure(NSError(
                    domain: "CVTemplateFetchService",
                    code: http.statusCode,
                    userInfo: [NSLocalizedDescriptionKey: "Template request failed with status \(http.statusCode)."]
                )))
            }
            return
        }
        do {
            let modelText = try Self.extractModelTextFromResponsesBody(data)
            let trimmed = modelText.trimmingCharacters(in: .whitespacesAndNewlines)
            guard !trimmed.isEmpty else {
                throw Self.emptyModelTextError
            }
            let decoded = try Self.decodeCatalog(fromModelText: trimmed)
            let mapped = decoded.compactMap { CVTemplate(aiItem: $0) }
            guard !mapped.isEmpty else {
                throw Self.noValidTemplatesError
            }
            var seen = Set<String>()
            let unique = mapped.filter { seen.insert($0.id).inserted }
            completion(.success(unique))
        } catch {
            if attempt == 0 {
                DispatchQueue.global(qos: .utility).asyncAfter(deadline: .now() + 2.0) {
                    refetchSameRequest(language: language, attempt: 1, completion: completion)
                }
                return
            }
            completion(.failure(error))
        }
    }

    private static func refetchSameRequest(
        language: AppLanguage,
        attempt: Int,
        completion: @escaping (Result<[CVTemplate], Error>) -> Void
    ) {
        let apiKey = OpenAIConfiguration.apiKey
        guard OpenAIConfiguration.hasAPIKey else {
            completion(.failure(missingKeyError))
            return
        }
        var request = URLRequest(url: URL(string: "https://api.openai.com/v1/responses")!)
        request.httpMethod = "POST"
        request.setValue("application/json", forHTTPHeaderField: "Content-Type")
        request.setValue("Bearer \(apiKey)", forHTTPHeaderField: "Authorization")
        request.timeoutInterval = 60
        guard let body = try? encodeCatalogRequestBody(language: language) else {
            completion(.failure(NSError(domain: "CVTemplateFetchService", code: 11, userInfo: [NSLocalizedDescriptionKey: "Could not encode request."])))
            return
        }
        request.httpBody = body
        URLSession(configuration: .ephemeral).dataTask(with: request) { data, response, error in
            handleFetchData(
                data,
                response: response,
                error: error,
                language: language,
                attempt: attempt,
                completion: completion
            )
        }.resume()
    }

    // MARK: - Errors

    private static let missingKeyError = NSError(
        domain: "CVTemplateFetchService",
        code: 1,
        userInfo: [NSLocalizedDescriptionKey: "Missing API key. Set OPENAI_API_KEY in the Run scheme environment for local debug."]
    )
    private static let emptyResponseError = NSError(
        domain: "CVTemplateFetchService",
        code: 2,
        userInfo: [NSLocalizedDescriptionKey: "API returned an empty response."]
    )
    private static let emptyModelTextError = NSError(
        domain: "CVTemplateFetchService",
        code: 4,
        userInfo: [NSLocalizedDescriptionKey: "The API returned an empty text payload."]
    )
    private static let noValidTemplatesError = NSError(
        domain: "CVTemplateFetchService",
        code: 10,
        userInfo: [NSLocalizedDescriptionKey: "The assistant reply did not include usable templates."]
    )

    // MARK: - Response parsing (mirrors OpenAI job search handling)

    private static func extractModelTextFromResponsesBody(_ data: Data) throws -> String {
        let rootObject: Any
        do {
            rootObject = try JSONSerialization.jsonObject(with: data, options: [])
        } catch {
            throw NSError(
                domain: "CVTemplateFetchService",
                code: 5,
                userInfo: [NSLocalizedDescriptionKey: "The service returned data that was not valid JSON."]
            )
        }
        guard let root = rootObject as? [String: Any] else {
            throw NSError(
                domain: "CVTemplateFetchService",
                code: 5,
                userInfo: [NSLocalizedDescriptionKey: "Unexpected response shape from the template service."]
            )
        }
        if let status = root["status"] as? String {
            if status == "failed" {
                let message = (root["error"] as? [String: Any])?["message"] as? String ?? "The request failed."
                throw NSError(domain: "CVTemplateFetchService", code: 7, userInfo: [NSLocalizedDescriptionKey: message])
            }
            if status == "incomplete",
               let details = root["incomplete_details"] as? [String: Any],
               let reason = details["reason"] as? String {
                throw NSError(
                    domain: "CVTemplateFetchService",
                    code: 8,
                    userInfo: [NSLocalizedDescriptionKey: "Request stopped early (\(reason)). Try again."]
                )
            }
        }
        if let direct = root["output_text"] as? String {
            let trimmed = direct.trimmingCharacters(in: .whitespacesAndNewlines)
            if !trimmed.isEmpty { return trimmed }
        }
        guard let output = root["output"] as? [Any] else {
            if let fallback = Self.scavengeTemplatesJSONString(fromUTF8Data: data) {
                return fallback
            }
            throw NSError(
                domain: "CVTemplateFetchService",
                code: 9,
                userInfo: [NSLocalizedDescriptionKey: "The service returned no assistant text. Try again."]
            )
        }
        var segments: [String] = []
        for case let item as [String: Any] in output where (item["type"] as? String) == "message" {
            collectOutputTextSegments(fromOutputItem: item, into: &segments)
        }
        if segments.isEmpty {
            for case let item as [String: Any] in output {
                collectOutputTextSegments(fromOutputItem: item, into: &segments)
            }
        }
        let combined = segments.joined(separator: "\n").trimmingCharacters(in: .whitespacesAndNewlines)
        if !combined.isEmpty {
            return combined
        }
        if let fallback = Self.scavengeTemplatesJSONString(fromUTF8Data: data) {
            return fallback
        }
        throw NSError(
            domain: "CVTemplateFetchService",
            code: 9,
            userInfo: [NSLocalizedDescriptionKey: "The model did not return readable text. Try again."]
        )
    }

    /// When `output` is missing, scan the raw body for a JSON object that contains `"templates"`.
    private static func scavengeTemplatesJSONString(fromUTF8Data data: Data) -> String? {
        guard let raw = String(data: data, encoding: .utf8) else { return nil }
        return extractTemplatesJSONObjectString(from: raw)
    }

    private static func collectOutputTextSegments(fromOutputItem item: [String: Any], into segments: inout [String]) {
        guard let content = item["content"] as? [Any] else { return }
        for case let part as [String: Any] in content {
            let type = (part["type"] as? String) ?? ""
            var candidate: String?
            if let s = part["text"] as? String {
                candidate = s
            } else if let nested = part["text"] as? [String: Any], let value = nested["value"] as? String {
                candidate = value
            } else if let j = part["json"] as? String {
                candidate = j
            } else if let jObj = part["json"] as? [String: Any],
                      let jData = try? JSONSerialization.data(withJSONObject: jObj, options: []),
                      let jStr = String(data: jData, encoding: .utf8) {
                candidate = jStr
            }
            guard let blob = candidate?.trimmingCharacters(in: .whitespacesAndNewlines), !blob.isEmpty else { continue }
            let looksLikeCatalog = blob.contains("\"templates\"") && blob.contains("{")
            if type == "output_text" || type == "output_json" || looksLikeCatalog {
                segments.append(blob)
            }
        }
    }

    private static func decodeCatalog(fromModelText text: String) throws -> [CVTemplateAIItem] {
        let stripped = text.trimmingCharacters(in: .whitespacesAndNewlines)
        if stripped.hasPrefix("{"), let directData = stripped.data(using: .utf8) {
            if let payload = try? JSONDecoder().decode(CVTemplateCatalogPayload.self, from: directData) {
                return payload.templates
            }
            if let flex = flexibleTemplates(fromJSONData: directData) {
                return flex
            }
        }
        let jsonString = extractTemplatesJSONObjectString(from: text) ?? extractJSONObject(from: text)
        let jsonData = Data(jsonString.utf8)
        if let payload = try? JSONDecoder().decode(CVTemplateCatalogPayload.self, from: jsonData) {
            return payload.templates
        }
        if let flex = flexibleTemplates(fromJSONData: jsonData) {
            return flex
        }
        throw NSError(
            domain: "CVTemplateFetchService",
            code: 10,
            userInfo: [NSLocalizedDescriptionKey: "The assistant reply was not valid template JSON."]
        )
    }

    private static func flexibleTemplates(fromJSONData data: Data) -> [CVTemplateAIItem]? {
        guard let obj = try? JSONSerialization.jsonObject(with: data, options: []) else { return nil }
        if let root = obj as? [String: Any] {
            if let items = templatesArray(from: root) {
                let mapped = items.compactMap { CVTemplateAIItem.fromFlexibleDictionary($0) }
                return mapped.isEmpty ? nil : mapped
            }
        }
        return nil
    }

    private static func templatesArray(from root: [String: Any]) -> [[String: Any]]? {
        if let arr = root["templates"] as? [[String: Any]] { return arr }
        for (_, value) in root {
            if let inner = value as? [String: Any], let arr = inner["templates"] as? [[String: Any]] {
                return arr
            }
        }
        return nil
    }

    private static func stripMarkdownCodeFence(_ text: String) -> String {
        var s = text.trimmingCharacters(in: .whitespacesAndNewlines)
        guard s.hasPrefix("```") else { return s }
        s.removeFirst(3)
        if s.lowercased().hasPrefix("json") {
            s.removeFirst(4)
        }
        s = s.trimmingCharacters(in: .whitespacesAndNewlines)
        if let fence = s.range(of: "```", options: .backwards) {
            s = String(s[..<fence.lowerBound])
        }
        return s.trimmingCharacters(in: .whitespacesAndNewlines)
    }

    private static func balancedJSONObject(from openBrace: String.Index, in s: String) -> String? {
        var depth = 0
        var inString = false
        var escaped = false
        var i = openBrace
        while i < s.endIndex {
            let ch = s[i]
            if inString {
                if escaped {
                    escaped = false
                } else if ch == "\\" {
                    escaped = true
                } else if ch == "\"" {
                    inString = false
                }
            } else {
                switch ch {
                case "\"":
                    inString = true
                case "{":
                    depth += 1
                case "}":
                    depth -= 1
                    if depth == 0 {
                        return String(s[openBrace...i])
                    }
                default:
                    break
                }
            }
            i = s.index(after: i)
        }
        return nil
    }

    private static func extractTemplatesJSONObjectString(from text: String) -> String? {
        let s = stripMarkdownCodeFence(text)
        guard let keyRange = s.range(of: "\"templates\"", options: .caseInsensitive) else { return nil }
        let head = s[..<keyRange.lowerBound]
        guard let open = head.lastIndex(of: "{") else { return nil }
        return balancedJSONObject(from: open, in: s)
    }

    private static func extractJSONObject(from text: String) -> String {
        if let extracted = extractTemplatesJSONObjectString(from: text) {
            return extracted
        }
        let stripped = stripMarkdownCodeFence(text)
        if let first = stripped.firstIndex(of: "{"), let balanced = balancedJSONObject(from: first, in: stripped) {
            return balanced
        }
        if let range = text.range(of: "\\{[\\s\\S]*\\}", options: .regularExpression) {
            return String(text[range])
        }
        return text
    }
}

// MARK: - AI DTO → CVTemplate

private struct CVTemplateCatalogPayload: Codable {
    let templates: [CVTemplateAIItem]
}

private struct CVTemplateAIItem: Codable {
    let id: String
    let name: String
    let family: String
    let headline: String
    let accent: String
    let layoutType: String
    let sidebarSide: String
    let sidebarTinted: Bool
    let sectionLabelStyle: String

    /// Decodes rows when keys differ slightly or booleans arrive as numbers.
    fileprivate static func fromFlexibleDictionary(_ dict: [String: Any]) -> CVTemplateAIItem? {
        func firstString(keys: [String]) -> String? {
            for wanted in keys {
                for (dk, dv) in dict {
                    guard dk.caseInsensitiveCompare(wanted) == .orderedSame else { continue }
                    if let s = dv as? String { return s }
                }
            }
            return nil
        }
        func firstBool(keys: [String]) -> Bool {
            for wanted in keys {
                for (dk, dv) in dict {
                    guard dk.caseInsensitiveCompare(wanted) == .orderedSame else { continue }
                    if let b = dv as? Bool { return b }
                    if let i = dv as? Int { return i != 0 }
                    if let s = dv as? String {
                        let t = s.trimmingCharacters(in: .whitespacesAndNewlines).lowercased()
                        if ["true", "1", "yes", "y"].contains(t) { return true }
                        if ["false", "0", "no", "n"].contains(t) { return false }
                    }
                }
            }
            return false
        }
        guard let id = firstString(keys: ["id"]),
              let name = firstString(keys: ["name"]),
              let family = firstString(keys: ["family"]),
              let headline = firstString(keys: ["headline"]),
              let accent = firstString(keys: ["accent"]),
              let layoutType = firstString(keys: ["layoutType", "layout_type"]),
              let sidebarSide = firstString(keys: ["sidebarSide", "sidebar_side"]),
              let sectionLabelStyle = firstString(keys: ["sectionLabelStyle", "section_label_style"])
        else { return nil }

        let tinted = firstBool(keys: ["sidebarTinted", "sidebar_tinted"])
        return CVTemplateAIItem(
            id: id,
            name: name,
            family: family,
            headline: headline,
            accent: accent,
            layoutType: layoutType,
            sidebarSide: sidebarSide,
            sidebarTinted: tinted,
            sectionLabelStyle: sectionLabelStyle
        )
    }
}

extension CVTemplate {
    fileprivate init?(aiItem: CVTemplateAIItem) {
        let id = Self.slugifyID(aiItem.id)
        let name = aiItem.name.trimmingCharacters(in: .whitespacesAndNewlines)
        guard !id.isEmpty, !name.isEmpty else { return nil }

        let familyNorm = aiItem.family.trimmingCharacters(in: .whitespacesAndNewlines).lowercased()
        guard let family = Self.parseDesignFamily(familyNorm) else { return nil }

        let headline = CVTemplate.parseHeadline(aiItem.headline)
        let accent = CVTemplate.parseAccent(aiItem.accent)
        let section = CVTemplate.parseSectionLabelStyle(aiItem.sectionLabelStyle)

        let layoutNorm = Self.normalizedSchemaToken(aiItem.layoutType)
        let layout: Layout
        switch layoutNorm {
        case "singlecolumn":
            layout = .singleColumn
        case "twocolumn":
            let sideKey = Self.normalizedSchemaToken(aiItem.sidebarSide)
            let side: SidebarSide = (sideKey == "trailing") ? .trailing : .leading
            layout = .twoColumn(sidebar: side, tinted: aiItem.sidebarTinted)
        default:
            layout = .singleColumn
        }

        self.init(
            id: id,
            name: name,
            family: family,
            headline: headline,
            accent: accent,
            layout: layout,
            sectionLabelStyle: section
        )
    }

    /// Collapses spaces and underscores so values like "Two Column" still map.
    private static func normalizedSchemaToken(_ raw: String) -> String {
        raw.trimmingCharacters(in: .whitespacesAndNewlines)
            .lowercased()
            .filter { !$0.isWhitespace }
            .replacingOccurrences(of: "_", with: "")
    }

    private static func parseDesignFamily(_ raw: String) -> CVDesignFamily? {
        let key = normalizedSchemaToken(raw)
        if let f = CVDesignFamily(rawValue: key) { return f }
        if key == "minimalist" { return .minimal }
        if key == "exec" { return .executive }
        return nil
    }

    private static func slugifyID(_ raw: String) -> String {
        let trimmed = raw.trimmingCharacters(in: .whitespacesAndNewlines).lowercased()
        guard !trimmed.isEmpty else { return "" }
        var out = ""
        var lastWasHyphen = false
        for ch in trimmed {
            if ch.isLetter || ch.isNumber {
                out.append(ch)
                lastWasHyphen = false
            } else if ch == "-" || ch == "_" || ch == " " {
                if !out.isEmpty, !lastWasHyphen {
                    out.append("-")
                    lastWasHyphen = true
                }
            }
        }
        while out.last == "-" { out.removeLast() }
        return out
    }

    private static func parseHeadline(_ s: String) -> Headline {
        let key = normalizedSchemaToken(s)
        switch key {
        case "centered": return .centered
        case "leftaligned", "left": return .leftAligned
        case "leftwithinitials", "initials": return .leftWithInitials
        case "avatarstacked", "stacked": return .avatarStacked
        default: return .leftAligned
        }
    }

    private static func parseAccent(_ s: String) -> Accent {
        let key = normalizedSchemaToken(s)
        switch key {
        case "none": return .none
        case "redunderline": return .redUnderline
        case "redbar": return .redBar
        case "bluebar": return .blueBar
        default: return .none
        }
    }

    private static func parseSectionLabelStyle(_ s: String) -> SectionLabelStyle {
        let key = normalizedSchemaToken(s)
        switch key {
        case "uppercase", "caps": return .uppercase
        case "slashed", "slash": return .slashed
        case "bracketed", "brackets": return .bracketed
        default: return .uppercase
        }
    }
}

// MARK: - OpenAI request types

private struct OpenAITemplatesAPIErrorResponse: Codable {
    let error: APIErrorPayload

    struct APIErrorPayload: Codable {
        let message: String
    }
}

private struct CVTemplateOpenAIRequest: Encodable {
    let model: String
    let instructions: String
    let input: String
    let text: CVTemplateOpenAITextOutputConfig

    static func catalogPayload(model: String, instructions: String, input: String) -> CVTemplateOpenAIRequest {
        let itemProperties = CVTemplateAIItemSchemaProperties(
            id: OpenAIJSONSchemaStringField(type: "string", description: "Unique kebab-case id."),
            name: OpenAIJSONSchemaStringField(type: "string", description: "Short display name."),
            family: OpenAIJSONSchemaStringEnum(
                type: "string",
                description: "Template style family.",
                enumValues: CVTemplateSchemaEnumValues.families
            ),
            headline: OpenAIJSONSchemaStringEnum(
                type: "string",
                description: "Header arrangement for the mini preview.",
                enumValues: CVTemplateSchemaEnumValues.headlines
            ),
            accent: OpenAIJSONSchemaStringEnum(
                type: "string",
                description: "Accent decoration.",
                enumValues: CVTemplateSchemaEnumValues.accents
            ),
            layoutType: OpenAIJSONSchemaStringEnum(
                type: "string",
                description: "Page layout.",
                enumValues: CVTemplateSchemaEnumValues.layouts
            ),
            sidebarSide: OpenAIJSONSchemaStringEnum(
                type: "string",
                description: "Sidebar column side when twoColumn.",
                enumValues: CVTemplateSchemaEnumValues.sides
            ),
            sidebarTinted: OpenAIJSONSchemaBooleanField(
                type: "boolean",
                description: "Tint sidebar column when twoColumn."
            ),
            sectionLabelStyle: OpenAIJSONSchemaStringEnum(
                type: "string",
                description: "Section heading style.",
                enumValues: CVTemplateSchemaEnumValues.sectionStyles
            )
        )
        let itemSchema = CVTemplateAIItemSchema(
            type: "object",
            properties: itemProperties,
            required: [
                "id", "name", "family", "headline", "accent",
                "layoutType", "sidebarSide", "sidebarTinted", "sectionLabelStyle"
            ],
            additionalProperties: false
        )
        let templatesProperty = CVTemplateTemplatesArrayProperty(
            type: "array",
            description: "Exactly 30 CV template definitions.",
            items: itemSchema
        )
        let rootProperties = CVTemplateCatalogRootProperties(templates: templatesProperty)
        let rootSchema = CVTemplateCatalogRootSchema(
            type: "object",
            properties: rootProperties,
            required: ["templates"],
            additionalProperties: false
        )
        let format = CVTemplateCatalogResponseJSONSchemaFormat(
            type: "json_schema",
            name: "cv_template_catalog",
            strict: true,
            schema: rootSchema
        )
        return CVTemplateOpenAIRequest(
            model: model,
            instructions: instructions,
            input: input,
            text: CVTemplateOpenAITextOutputConfig(format: format)
        )
    }
}

private struct CVTemplateOpenAITextOutputConfig: Encodable {
    let format: CVTemplateCatalogResponseJSONSchemaFormat
}

private struct CVTemplateCatalogResponseJSONSchemaFormat: Encodable {
    let type: String
    let name: String
    let strict: Bool
    let schema: CVTemplateCatalogRootSchema
}

private struct CVTemplateCatalogRootSchema: Encodable {
    let type: String
    let properties: CVTemplateCatalogRootProperties
    let required: [String]
    let additionalProperties: Bool
}

private struct CVTemplateCatalogRootProperties: Encodable {
    let templates: CVTemplateTemplatesArrayProperty
}

private enum CVTemplateSchemaEnumValues {
    static let families = ["creative", "executive", "minimal", "modern", "professional"]
    static let headlines = ["avatarStacked", "centered", "leftAligned", "leftWithInitials"]
    static let accents = ["blueBar", "none", "redBar", "redUnderline"]
    static let layouts = ["singleColumn", "twoColumn"]
    static let sides = ["leading", "trailing"]
    static let sectionStyles = ["bracketed", "slashed", "uppercase"]
}

private struct CVTemplateTemplatesArrayProperty: Encodable {
    let type: String
    let description: String
    let items: CVTemplateAIItemSchema
}

private struct CVTemplateAIItemSchema: Encodable {
    let type: String
    let properties: CVTemplateAIItemSchemaProperties
    let required: [String]
    let additionalProperties: Bool
}

private struct CVTemplateAIItemSchemaProperties: Encodable {
    let id: OpenAIJSONSchemaStringField
    let name: OpenAIJSONSchemaStringField
    let family: OpenAIJSONSchemaStringEnum
    let headline: OpenAIJSONSchemaStringEnum
    let accent: OpenAIJSONSchemaStringEnum
    let layoutType: OpenAIJSONSchemaStringEnum
    let sidebarSide: OpenAIJSONSchemaStringEnum
    let sidebarTinted: OpenAIJSONSchemaBooleanField
    let sectionLabelStyle: OpenAIJSONSchemaStringEnum
}

private struct OpenAIJSONSchemaStringEnum: Encodable {
    let type: String
    let description: String
    let enumValues: [String]

    enum CodingKeys: String, CodingKey {
        case type, description
        case enumValues = "enum"
    }
}

private struct OpenAIJSONSchemaStringField: Encodable {
    let type: String
    let description: String
}

private struct OpenAIJSONSchemaBooleanField: Encodable {
    let type: String
    let description: String
}