// Views/Dashboard/SyncStatusView.swift
import SwiftUI
import SwiftData
import MessageUI

// MARK: - Sync Status View

struct SyncStatusView: View {
    @EnvironmentObject private var sync: SyncManager
    @Environment(\.modelContext) private var context

    @Query(
        filter: #Predicate<LocalInspection> { $0.syncStatus == "pending" || $0.syncStatus == "failed" },
        sort: \LocalInspection.createdAt
    ) private var pendingInspections: [LocalInspection]

    @Query(
        filter: #Predicate<LocalIssue> { $0.syncStatus == "pending" || $0.syncStatus == "failed" },
        sort: \LocalIssue.createdAt
    ) private var pendingIssues: [LocalIssue]

    private var failedInspections: [LocalInspection] { pendingInspections.filter { $0.syncStatus == "failed" } }
    private var failedIssues: [LocalIssue]            { pendingIssues.filter      { $0.syncStatus == "failed" } }
    private var hasFailedItems: Bool { !failedInspections.isEmpty || !failedIssues.isEmpty }

    var body: some View {
        List {
            Section("Status") {
                HStack {
                    Circle().fill(sync.isOnline ? Color.green : Color.orange)
                        .frame(width: 8, height: 8)
                    Text(sync.isOnline ? "Online" : "Offline")
                }
                if let lastSync = sync.lastSyncAt {
                    LabeledContent("Last Sync",
                                   value: lastSync.formatted(date: .abbreviated, time: .shortened))
                }
                if sync.isSyncing {
                    HStack {
                        ProgressView()
                        Text("Syncing…").foregroundStyle(.secondary)
                    }
                }
                if let error = sync.syncError {
                    Text(error).foregroundStyle(.red).font(.callout)
                }
                Button {
                    Task { await sync.triggerSync() }
                } label: {
                    Label("Sync Now", systemImage: "arrow.clockwise")
                }
                .disabled(!sync.isOnline || sync.isSyncing)

                // Retry Failed Items — resets syncStatus back to "pending" so
                // the next triggerSync() will re-attempt them. Once an item
                // reaches syncStatus = "failed" (after 5 consecutive errors)
                // triggerSync() stops picking it up — this is the only way
                // to re-queue it without manual server intervention.
                if hasFailedItems {
                    Button {
                        retryAllFailed()
                    } label: {
                        Label("Retry Failed Items (\(failedInspections.count + failedIssues.count))",
                              systemImage: "exclamationmark.arrow.circlepath")
                            .foregroundStyle(.orange)
                    }
                    .disabled(!sync.isOnline || sync.isSyncing)
                }
            }

            if !pendingInspections.isEmpty {
                Section("Pending Inspections (\(pendingInspections.count))") {
                    ForEach(pendingInspections) { insp in
                        SyncRowView(title: "Inspection", status: insp.syncStatus,
                                    retryCount: insp.syncRetryCount,
                                    error: insp.syncErrorMessage, date: insp.createdAt)
                    }
                }
            }

            if !pendingIssues.isEmpty {
                Section("Pending Issues (\(pendingIssues.count))") {
                    ForEach(pendingIssues) { issue in
                        SyncRowView(title: "\(issue.severity.capitalized) Issue",
                                    status: issue.syncStatus, retryCount: issue.syncRetryCount,
                                    error: issue.syncErrorMessage, date: issue.createdAt)
                    }
                }
            }

            if pendingInspections.isEmpty && pendingIssues.isEmpty && !sync.isSyncing {
                Section {
                    Label("All items synced.", systemImage: "checkmark.circle.fill")
                        .foregroundStyle(.green)
                }
            }
        }
        .navigationTitle("Pending Sync")
    }

    /// Reset all failed items back to pending so the next sync pass picks them up.
    /// Also clears syncRetryCount and syncErrorMessage so the retry counter
    /// starts fresh — prevents them immediately hitting the 5-retry cap again
    /// without any actual new attempt.
    private func retryAllFailed() {
        for insp in failedInspections {
            insp.syncStatus       = "pending"
            insp.syncRetryCount   = 0
            insp.syncErrorMessage = nil
        }
        for issue in failedIssues {
            issue.syncStatus       = "pending"
            issue.syncRetryCount   = 0
            issue.syncErrorMessage = nil
        }
        try? context.save()
        Task { await sync.triggerSync() }
    }
}

struct SyncRowView: View {
    let title: String
    let status: String
    let retryCount: Int
    let error: String?
    let date: Date

    var body: some View {
        VStack(alignment: .leading, spacing: 4) {
            HStack {
                Text(title).font(.callout)
                Spacer()
                Text(status.capitalized).font(.caption2)
                    .foregroundStyle(status == "failed" ? .red : .orange)
            }
            Text(date.formatted(date: .abbreviated, time: .shortened))
                .font(.caption2).foregroundStyle(.tertiary)
            if let err = error {
                Text(err).font(.caption2).foregroundStyle(.red).lineLimit(2)
            }
            if retryCount > 0 {
                Text("Retried \(retryCount) time\(retryCount == 1 ? "" : "s")")
                    .font(.caption2).foregroundStyle(.secondary)
            }
        }
        .padding(.vertical, 2)
    }
}