// Views/Inspection/StartInspectionView.swift
// ------------------------------------------
// Screen where the inspector chooses a template, facility, and optional area
// before starting a new inspection. Creates the LocalInspection record
// immediately so the form can be resumed if the app is backgrounded.

import SwiftUI
import SwiftData

struct StartInspectionView: View {

    @Environment(\.modelContext) private var context
    @Environment(\.dismiss) private var dismiss

    @Query(sort: \LocalTemplate.name)  private var templates:  [LocalTemplate]
    @Query(sort: \LocalFacility.name)  private var facilities: [LocalFacility]

    @State private var selectedTemplateId: Int?
    @State private var selectedFacilityId: Int?
    @State private var selectedAreaId: Int?
    @State private var navigateToExecution = false
    @State private var createdInspection: LocalInspection?

    @EnvironmentObject private var auth: AuthManager

    private var selectedFacility: LocalFacility? {
        facilities.first { $0.serverId == selectedFacilityId }
    }

    private var areas: [LocalArea] {
        selectedFacility?.areas.sorted { $0.name < $1.name } ?? []
    }

    private var canStart: Bool {
        selectedTemplateId != nil && selectedFacilityId != nil
    }

    var body: some View {
        NavigationStack {
            Form {
                // ── Template picker ────────────────────────────────────────
                Section("Inspection Template") {
                    if templates.isEmpty {
                        Text("No templates available. Sync required.")
                            .foregroundStyle(.secondary)
                            .font(.callout)
                    } else {
                        Picker("Template", selection: $selectedTemplateId) {
                            Text("Select a template…").tag(Optional<Int>(nil))
                            ForEach(templates) { template in
                                VStack(alignment: .leading) {
                                    Text(template.name)
                                    if !template.frequency.isEmpty {
                                        Text(template.frequencyLabel)
                                            .font(.caption)
                                            .foregroundStyle(.secondary)
                                    }
                                }
                                .tag(Optional(template.serverId))
                            }
                        }
                        .pickerStyle(.navigationLink)
                    }
                }

                // ── Facility picker ────────────────────────────────────────
                Section("Facility") {
                    if facilities.isEmpty {
                        Text("No facilities available. Sync required.")
                            .foregroundStyle(.secondary)
                            .font(.callout)
                    } else {
                        Picker("Facility", selection: $selectedFacilityId) {
                            Text("Select a facility…").tag(Optional<Int>(nil))
                            ForEach(facilities) { facility in
                                Text(facility.name).tag(Optional(facility.serverId))
                            }
                        }
                        .pickerStyle(.navigationLink)
                        .onChange(of: selectedFacilityId) {
                            selectedAreaId = nil  // reset area when facility changes
                        }
                    }
                }

                // ── Area picker (optional) ─────────────────────────────────
                if selectedFacilityId != nil {
                    Section("Area (Optional)") {
                        Picker("Area", selection: $selectedAreaId) {
                            Text("No specific area").tag(Optional<Int>(nil))
                            ForEach(areas) { area in
                                Text(area.name).tag(Optional(area.serverId))
                            }
                        }
                        .pickerStyle(.navigationLink)
                        .disabled(areas.isEmpty)
                    }
                }

                // ── Start button ───────────────────────────────────────────
                Section {
                    Button {
                        startInspection()
                    } label: {
                        HStack {
                            Spacer()
                            Label("Start Inspection", systemImage: "play.circle.fill")
                                .font(.headline)
                            Spacer()
                        }
                    }
                    .disabled(!canStart)
                }
            }
            .navigationTitle("New Inspection")
            .navigationBarTitleDisplayMode(.large)
            .toolbar {
                ToolbarItem(placement: .cancellationAction) {
                    Button("Cancel") { dismiss() }
                }
            }
            .navigationDestination(isPresented: $navigateToExecution) {
                if let inspection = createdInspection {
                    ExecuteInspectionView(inspection: inspection)
                }
            }
        }
    }

    private func startInspection() {
        guard let templateId = selectedTemplateId,
              let facilityId = selectedFacilityId
        else { return }

        let inspection = LocalInspection(
            templateServerId: templateId,
            facilityServerId: facilityId,
            areaServerId:     selectedAreaId,
            inspectorUserId:  auth.currentUserId
        )
        context.insert(inspection)
        try? context.save()

        createdInspection   = inspection
        navigateToExecution = true
    }
}