//
//  ChatView.swift
//  Poche
//
//  Author:  Simon-Pierre Boucher
//  Contact: contact@spboucher.ai
//

import SwiftUI

/// Single screen: thread, pending confirmations, composer.
/// No tabs, no settings menu on first launch (CLAUDE.md §6).
struct ChatView: View {
    @Environment(AppDependencies.self) private var deps

    var body: some View {
        @Bindable var chat = deps.chat

        ZStack {
            AppBackground()

            VStack(spacing: 0) {
                header

                if chat.turns.isEmpty {
                    WelcomeView { suggestion in
                        Task { await chat.send(suggestion) }
                    }
                } else {
                    thread(chat: chat)
                }

                ForEach(deps.confirm.pending) { action in
                    ConfirmationCardView(
                        action: action,
                        onConfirm: { Task { await deps.confirm.confirm(action) } },
                        onModify: { deps.confirm.dismiss(action) }
                    )
                    .padding(.horizontal, Theme.spacingMedium)
                    .padding(.bottom, Theme.spacingSmall)
                    .transition(.move(edge: .bottom).combined(with: .opacity))
                }

                ComposerView(
                    text: $chat.draft,
                    isBusy: chat.isBusy,
                    onSend: { Task { await chat.send() } }
                )
            }
            .animation(.spring(duration: 0.35), value: deps.confirm.pending.count)
        }
        .fontDesign(.rounded)
        .task {
            #if DEBUG
            // Deterministic driving hooks for simulator verification only.
            let env = ProcessInfo.processInfo.environment
            if env["POCHE_DEMO_THREAD"] != nil, chat.turns.isEmpty {
                chat.injectDemoTurns()
            }
            if env["POCHE_DEMO_CARD"] != nil, deps.confirm.pending.isEmpty {
                deps.confirm.propose(PendingAction(payload: .reminder(
                    ReminderDraft(title: "Appeler le dentiste", due: .now.addingTimeInterval(86_400), list: nil)
                )))
            }
            if let text = env["POCHE_AUTOSEND"], chat.turns.isEmpty {
                await chat.send(text)
            }
            #endif
        }
    }

    private var header: some View {
        VStack(spacing: 0) {
            HStack(spacing: Theme.spacingSmall + 2) {
                BrandMark(size: 30)
                Text("Poche")
                    .font(.title3.weight(.bold))
                Spacer()
            }
            .padding(.horizontal, Theme.spacingMedium + 4)
            .padding(.vertical, Theme.spacingSmall + 2)

            ContextGaugeView(ratio: deps.agent.usageRatio)
                .padding(.horizontal, Theme.spacingMedium)
        }
    }

    private func thread(chat: ChatViewModel) -> some View {
        ScrollView {
            LazyVStack(spacing: Theme.spacingMedium) {
                ForEach(chat.turns) { turn in
                    TurnBubbleView(turn: turn)
                        .transition(.move(edge: .bottom).combined(with: .opacity))
                }
            }
            .padding(.horizontal, Theme.spacingMedium)
            .padding(.vertical, Theme.spacingLarge)
            .animation(.spring(duration: 0.35), value: chat.turns.count)
        }
        .defaultScrollAnchor(.bottom)
        .scrollDismissesKeyboard(.interactively)
    }
}