import SwiftUI

/// VL 解析后的可编辑表单。
/// 用户可改 title / type / reportDate / institution / summary / 各 indicator;
/// 也可删除识别错的 indicator,或手加一行。
/// 「保存」回调写 SwiftData + 关联已写入 Vault 的 assets。
struct CaptureReviewForm: View {
    @State var parsed: ParsedReport
    let assets: [FileVault.SavedAsset]
    let warning: String?
    let onSave: (ParsedReport) -> Void
    let onCancel: () -> Void
    /// 「重新识别」回调。assets 为空(写图失败)时传 nil,banner 上不显示该按钮。
    var onReanalyze: (() -> Void)? = nil

    var body: some View {
        ScrollView {
            VStack(alignment: .leading, spacing: 18) {
                if let warning {
                    warningBanner(warning)
                }
                if !assets.isEmpty {
                    pageThumbnails
                }
                metaSection
                indicatorSection
                Spacer(minLength: 8)
                actions
            }
            .padding(.horizontal, 18)
            .padding(.bottom, 24)
        }
    }

    // MARK: - 顶部 warning

    private func warningBanner(_ text: String) -> some View {
        HStack(alignment: .top, spacing: 8) {
            Image(systemName: "exclamationmark.triangle.fill")
                .foregroundStyle(Tj.Palette.amber)
            VStack(alignment: .leading, spacing: 8) {
                Text(text)
                    .font(.system(size: 12))
                    .foregroundStyle(Tj.Palette.text2)
                    .fixedSize(horizontal: false, vertical: true)
                if let onReanalyze {
                    Button {
                        onReanalyze()
                    } label: {
                        Label("重新识别", systemImage: "arrow.clockwise")
                            .font(.system(size: 12, weight: .semibold))
                    }
                    .buttonStyle(.plain)
                    .foregroundStyle(Tj.Palette.ink)
                }
            }
            Spacer(minLength: 0)
        }
        .padding(12)
        .background(
            RoundedRectangle(cornerRadius: Tj.Radius.sm, style: .continuous)
                .fill(Tj.Palette.brickSoft.opacity(0.5))
        )
    }

    // MARK: - 缩略图

    private var pageThumbnails: some View {
        VStack(alignment: .leading, spacing: 8) {
            sectionLabel(String(appLoc: "已保存 \(assets.count) 页(端侧加密)"))
            ScrollView(.horizontal, showsIndicators: false) {
                HStack(spacing: 10) {
                    ForEach(Array(assets.enumerated()), id: \.offset) { _, asset in
                        if let img = try? FileVault.shared.loadImage(relativePath: asset.relativePath) {
                            Image(uiImage: img)
                                .resizable()
                                .scaledToFill()
                                .frame(width: 84, height: 110)
                                .clipShape(RoundedRectangle(cornerRadius: 8, style: .continuous))
                                .overlay(
                                    RoundedRectangle(cornerRadius: 8, style: .continuous)
                                        .strokeBorder(Tj.Palette.line, lineWidth: 1)
                                )
                        }
                    }
                }
            }
        }
    }

    // MARK: - meta(title / type / date / institution / summary)

    private var metaSection: some View {
        VStack(alignment: .leading, spacing: 12) {
            sectionLabel(String(appLoc: "基本信息"))
            VStack(spacing: 10) {
                labeledField(String(appLoc: "标题")) {
                    TextField("如:春季年度体检", text: $parsed.title)
                        .textFieldStyle(.plain)
                }
                labeledField(String(appLoc: "类型")) {
                    Picker("", selection: $parsed.typeRaw) {
                        ForEach(ReportType.allCases, id: \.rawValue) { t in
                            Text(t.label).tag(t.rawValue)
                        }
                    }
                    .pickerStyle(.segmented)
                }
                labeledField(String(appLoc: "报告日期")) {
                    DatePicker("", selection: $parsed.reportDate,
                               in: ...Date.now,
                               displayedComponents: .date)
                        .datePickerStyle(.compact)
                        .labelsHidden()
                        .environment(\.locale, Locale.current)
                }
                labeledField(String(appLoc: "机构(可选)")) {
                    TextField("如:协和医院", text: $parsed.institution)
                }
                labeledField(String(appLoc: "摘要(可选)")) {
                    TextField("一句话总结", text: $parsed.summary, axis: .vertical)
                        .lineLimit(1...3)
                }
            }
            .padding(12)
            .background(fieldBg)
            .overlay(fieldBorder)
        }
    }

    private func labeledField<C: View>(_ label: String, @ViewBuilder content: () -> C) -> some View {
        VStack(alignment: .leading, spacing: 4) {
            Text(label)
                .font(.system(size: 11, weight: .medium))
                .foregroundStyle(Tj.Palette.text3)
            content()
        }
    }

    // MARK: - indicators

    private var indicatorSection: some View {
        VStack(alignment: .leading, spacing: 10) {
            HStack {
                sectionLabel(String(appLoc: "指标(\(parsed.indicators.count) 项)"))
                Spacer()
                Button {
                    parsed.indicators.append(
                        .init(name: "", value: "", unit: "", range: "", status: .normal)
                    )
                } label: {
                    Label("加一项", systemImage: "plus.circle")
                        .font(.system(size: 12, weight: .medium))
                }
                .buttonStyle(.plain)
                .foregroundStyle(Tj.Palette.ink)
            }
            if parsed.indicators.isEmpty {
                Text("没有指标 — 点上方「加一项」补一行,或直接保存只存图片")
                    .font(.system(size: 12))
                    .foregroundStyle(Tj.Palette.text3)
                    .padding(.vertical, 8)
            } else {
                VStack(spacing: 10) {
                    ForEach($parsed.indicators) { $indicator in
                        indicatorRow($indicator)
                    }
                }
            }
        }
    }

    private func indicatorRow(_ binding: Binding<ParsedReport.ParsedIndicator>) -> some View {
        let id = binding.wrappedValue.id
        return VStack(spacing: 8) {
            HStack(spacing: 8) {
                TextField("指标名", text: binding.name)
                    .font(.system(size: 14, weight: .medium))
                Button(role: .destructive) {
                    parsed.indicators.removeAll { $0.id == id }
                } label: {
                    Image(systemName: "minus.circle.fill")
                        .foregroundStyle(Tj.Palette.text3)
                }
                .buttonStyle(.plain)
            }
            HStack(spacing: 8) {
                TextField("数值", text: binding.value)
                    .keyboardType(.decimalPad)
                    .font(.system(size: 14, weight: .semibold, design: .monospaced))
                    .frame(maxWidth: 90)
                TextField("单位", text: binding.unit)
                    .frame(maxWidth: 80)
                    .autocorrectionDisabled()
                TextField("参考", text: binding.range)
                    .autocorrectionDisabled()
            }
            Picker("", selection: binding.status) {
                Text("正常").tag(IndicatorStatus.normal)
                Text("偏高 ↑").tag(IndicatorStatus.high)
                Text("偏低 ↓").tag(IndicatorStatus.low)
            }
            .pickerStyle(.segmented)
        }
        .padding(12)
        .background(
            RoundedRectangle(cornerRadius: Tj.Radius.sm, style: .continuous)
                .fill(Tj.Palette.paper)
        )
        .overlay(
            RoundedRectangle(cornerRadius: Tj.Radius.sm, style: .continuous)
                .strokeBorder(statusColor(binding.status.wrappedValue).opacity(0.4),
                              lineWidth: 1)
        )
    }

    private func statusColor(_ s: IndicatorStatus) -> Color {
        switch s {
        case .normal: return Tj.Palette.leaf
        case .high:   return Tj.Palette.brick
        case .low:    return Tj.Palette.amber
        }
    }

    // MARK: - actions

    private var actions: some View {
        VStack(spacing: 10) {
            Button {
                onSave(parsed)
            } label: {
                Text("保存到记录")
                    .frame(maxWidth: .infinity)
            }
            .buttonStyle(TjPrimaryButton())

            Button(action: onCancel) {
                Text("取消(图片不保留)")
                    .frame(maxWidth: .infinity)
                    .foregroundStyle(Tj.Palette.text3)
            }
            .buttonStyle(.plain)
        }
    }

    // MARK: - helpers

    private func sectionLabel(_ t: String) -> some View {
        Text(t)
            .font(.system(size: 12, weight: .semibold))
            .tracking(0.3)
            .foregroundStyle(Tj.Palette.text2)
    }

    private var fieldBg: some View {
        RoundedRectangle(cornerRadius: Tj.Radius.sm, style: .continuous)
            .fill(Tj.Palette.paper)
    }

    private var fieldBorder: some View {
        RoundedRectangle(cornerRadius: Tj.Radius.sm, style: .continuous)
            .strokeBorder(Tj.Palette.line, lineWidth: 1)
    }
}