gramora/gramora/ViewModels/EmailWriterViewModel.swift

import AppKit
import Combine
import Foundation

@MainActor
final class EmailWriterViewModel: ObservableObject {
    static let maxCharacters = 5_000

    @Published var subject: String = ""
    @Published var prompt: String = ""
    @Published var generatedEmail: String = ""
    @Published var emailType: EmailType = .followUp
    @Published var tone: EmailTone = .professional
    @Published var isGenerating = false

    var characterCount: Int { prompt.count }

    var characterCountLabel: String {
        "\(characterCount)/\(Self.maxCharacters)"
    }

    var canGenerate: Bool {
        !prompt.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty && !isGenerating
    }

    var canCopy: Bool {
        !generatedEmail.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty
    }

    func pastePrompt() {
        guard let clipboard = NSPasteboard.general.string(forType: .string) else { return }
        prompt = String(clipboard.prefix(Self.maxCharacters))
    }

    func clearAll() {
        subject = ""
        prompt = ""
        generatedEmail = ""
    }

    func copyGeneratedEmail() {
        guard canCopy else { return }
        NSPasteboard.general.clearContents()
        NSPasteboard.general.setString(generatedEmail, forType: .string)
    }

    func generateEmail() {
        let trimmedPrompt = prompt.trimmingCharacters(in: .whitespacesAndNewlines)
        guard !trimmedPrompt.isEmpty else { return }

        isGenerating = true
        generatedEmail = ""

        // Email generation service integration point
        let subjectLine = subject.trimmingCharacters(in: .whitespacesAndNewlines)
        let greeting = tone == .formal ? "Dear Recipient," : "Hi there,"

        var email = "\(greeting)\n\n"
        email += "[\(emailType.title) · \(tone.title)]\n\n"
        email += trimmedPrompt
        email += "\n\nBest regards,\n[Your Name]"

        if !subjectLine.isEmpty {
            email = "Subject: \(subjectLine)\n\n" + email
        }

        generatedEmail = email
        isGenerating = false
    }
}