RestorePpBattleMutationInterceptor.kt

package io.github.lishangbu.avalon.game.battle.engine.core.runtime.flow

import io.github.lishangbu.avalon.game.battle.engine.core.constant.BattleAttributeKeys
import io.github.lishangbu.avalon.game.battle.engine.core.event.StandardHookNames
import io.github.lishangbu.avalon.game.battle.engine.core.mutation.BattleMutation
import io.github.lishangbu.avalon.game.battle.engine.core.mutation.RestorePpMutation
import io.github.lishangbu.avalon.game.battle.engine.core.runtime.support.MutationTargetSelectorResolver

/**
 * PP 回复 mutation 的生命周期拦截器。
 *
 * 当前职责：
 * - `on_restore_pp` 派发；
 * - veto 能力；
 * - 在 hook 返回整数 relay 时，把新的 PP 回复量真正回写到 mutation。
 *
 * 注意：
 * - 一条 `RestorePpMutation` 可能对应多个目标；
 * - 由于当前 mutation 仍是“共享负载”，只有当所有目标都给出一致的新数值时，
 *   这里才会执行 rewrite，避免把最后一个目标的 relay 静默覆盖到前面目标。
 */
class RestorePpBattleMutationInterceptor : BattleMutationInterceptor {
    override val order: Int = 550

    override fun supports(mutation: BattleMutation): Boolean = mutation is RestorePpMutation

    override fun intercept(
        context: BattleMutationInterceptionContext,
        attachedEffectProcessor: BattleAttachedEffectProcessor,
    ): BattleMutationInterceptionResult {
        val mutation =
            context.mutation as? RestorePpMutation
                ?: return BattleMutationInterceptionResult(context.snapshot, true, context.mutation)
        val targetUnitIds =
            MutationTargetSelectorResolver.resolve(
                mutation.target,
                BattleMutationInterceptorSupport.mutationApplicationContext(context),
            )
        var currentSnapshot = context.snapshot
        var blocked = false
        var rewrittenValue: Int? = null
        var rewriteConflicted = false

        targetUnitIds.forEach { affectedTargetId ->
            val result =
                attachedEffectProcessor.process(
                    snapshot = currentSnapshot,
                    unitId = affectedTargetId,
                    hookName = StandardHookNames.ON_RESTORE_PP.value,
                    targetId = affectedTargetId,
                    sourceId = context.sourceId,
                    relay = mutation.value,
                    attributes =
                        buildMap {
                            put("value", mutation.value)
                            mutation.moveId?.let { moveId -> put("moveId", moveId) }
                            BattleMutationInterceptorSupport
                                .resolveTargetRelation(currentSnapshot, context.sourceId, affectedTargetId)
                                ?.let { relation -> put(BattleAttributeKeys.TARGET_RELATION, relation) }
                        },
                )
            currentSnapshot = result.snapshot
            if (result.cancelled || result.relay == false) {
                blocked = true
                return@forEach
            }

            val relayValue = BattleMutationInterceptorSupport.normalizeIntegerRelay(result.relay) ?: return@forEach
            if (targetUnitIds.size == 1) {
                rewrittenValue = relayValue.coerceAtLeast(0)
                return@forEach
            }
            if (rewrittenValue == null) {
                rewrittenValue = relayValue.coerceAtLeast(0)
            } else if (rewrittenValue != relayValue.coerceAtLeast(0)) {
                rewriteConflicted = true
            }
        }

        val nextMutation =
            if (!blocked && !rewriteConflicted && rewrittenValue != null) {
                mutation.copy(value = requireNotNull(rewrittenValue))
            } else {
                mutation
            }

        return BattleMutationInterceptionResult(
            snapshot = currentSnapshot,
            allowed = !blocked,
            mutation = nextMutation,
        )
    }
}