package com.goldenchart.service;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.ObjectNode;

import java.util.Map;
import java.util.Locale;

/**
 * 전략 조건 DSL — K_50 등 직접입력 스냅샷을 hline 역할(HL_MID 등)로 정규화.
 * 프론트 normalizeConditionForPersistence 와 동일 의도.
 */
public final class StrategyConditionThresholdNormalizer {

    private StrategyConditionThresholdNormalizer() {}

    public static JsonNode normalizeTree(JsonNode root) {
        if (root == null || root.isNull() || !root.isObject()) return root;
        ObjectNode copy = root.deepCopy();
        walk(copy);
        return copy;
    }

    private static void walk(JsonNode node) {
        if (node == null || !node.isObject()) return;

        JsonNode cond = node.get("condition");
        if (cond != null && cond.isObject()) {
            normalizeCondition((ObjectNode) cond);
        } else if (node.has("indicatorType") && node.has("conditionType")) {
            normalizeCondition((ObjectNode) node);
        }

        JsonNode children = node.get("children");
        if (children != null && children.isArray()) {
            for (JsonNode c : children) walk(c);
        }
        JsonNode child = node.get("child");
        if (child != null) walk(child);
    }

    private static void normalizeCondition(ObjectNode cond) {
        String indType = cond.path("indicatorType").asText("").toUpperCase(Locale.ROOT);
        if (!indType.isBlank()) {
            cond.put("indicatorType", indType);
        }
        normalizeThresholdField(cond, "rightField", indType);
        normalizeThresholdField(cond, "leftField", indType);
    }

    private static void normalizeThresholdField(ObjectNode cond, String fieldKey, String indType) {
        String field = cond.path(fieldKey).asText("");
        if (field.isBlank()) return;

        boolean override = cond.path("thresholdOverride").asBoolean(false);
        Double value = readThresholdValue(cond, field);

        if (override || field.startsWith("K_")) {
            String role = inferRoleForValue(indType, value, field);
            if (role != null) {
                cond.put(fieldKey, role);
                cond.remove("targetValue");
                cond.put("thresholdOverride", false);
                return;
            }
        }

        if (!override && field.startsWith("K_")) {
            String role = inferRoleForValue(indType, value, field);
            if (role != null) {
                cond.put(fieldKey, role);
                cond.remove("targetValue");
                cond.put("thresholdOverride", false);
            }
        }
    }

    private static Double readThresholdValue(ObjectNode cond, String field) {
        if (cond.has("targetValue") && !cond.path("targetValue").isNull()) {
            return cond.path("targetValue").asDouble();
        }
        if (field.startsWith("K_")) {
            try {
                return Double.parseDouble(field.substring(2));
            } catch (NumberFormatException ignored) {
                return null;
            }
        }
        return null;
    }

    private static String inferRoleForValue(String indicatorType, Double value, String field) {
        if (value == null && field.startsWith("K_")) {
            try {
                value = Double.parseDouble(field.substring(2));
            } catch (NumberFormatException ignored) {
                return null;
            }
        }
        if (value == null || !Double.isFinite(value)) return null;

        double eps = 0.0001;
        for (Map.Entry<String, Double> e : defaultRoles(indicatorType).entrySet()) {
            if (Math.abs(e.getValue() - value) < eps) {
                return e.getKey();
            }
        }
        return null;
    }

    /** HL_OVER / HL_MID / HL_UNDER → 기본 숫자 (IndicatorHlineResolver.defaultForRole 과 동일) */
    private static Map<String, Double> defaultRoles(String indicatorType) {
        return switch (indicatorType) {
            case "RSI" -> Map.of("HL_OVER", 70.0, "HL_MID", 50.0, "HL_UNDER", 30.0);
            case "STOCHASTIC" -> Map.of("HL_OVER", 80.0, "HL_MID", 50.0, "HL_UNDER", 20.0);
            case "CCI" -> Map.of("HL_OVER", 100.0, "HL_MID", 0.0, "HL_UNDER", -100.0);
            case "WILLIAMS_R" -> Map.of("HL_OVER", -20.0, "HL_MID", -50.0, "HL_UNDER", -80.0);
            case "ADX" -> Map.of("HL_MID", 25.0);
            case "DISPARITY" -> Map.of("HL_MID", 100.0);
            case "VOLUME_OSC", "TRIX", "MACD" -> Map.of("HL_MID", 0.0);
            default -> Map.of();
        };
    }

    /** JSON 문자열 보정 — 파싱 실패 시 원본 반환 */
    public static String normalizeJson(String json, com.fasterxml.jackson.databind.ObjectMapper mapper) {
        if (json == null || json.isBlank()) return json;
        try {
            JsonNode root = mapper.readTree(json);
            JsonNode normalized = normalizeTree(root);
            return mapper.writeValueAsString(normalized);
        } catch (Exception ignored) {
            return json;
        }
    }
}