/**
 * 环境系统 - 环境惩罚计算、被动技能获取
 * Phase 6 核心系统实现
 */

import { LOCATION_CONFIG } from '@/config/locations.js'
import { SKILL_CONFIG } from '@/config/skills.js'

/**
 * 环境类型枚举
 */
export const ENVIRONMENT_TYPES = {
  NORMAL: 'normal',   // 普通环境
  DARK: 'dark',       // 黑暗环境
  NARROW: 'narrow',   // 狭窄空间
  HARSH: 'harsh'      // 恶劣环境
}

/**
 * 环境惩罚配置
 */
const ENVIRONMENT_PENALTIES = {
  [ENVIRONMENT_TYPES.DARK]: {
    apPenalty: 0.2,      // AP -20%
    epPenalty: 0.2,      // EP -20%
    readingPenalty: 0.5, // 阅读效率 -50%
    adaptSkill: 'night_vision',  // 适应技能
    description: '黑暗'
  },
  [ENVIRONMENT_TYPES.NARROW]: {
    apPenalty: 0,        // AP 无惩罚
    epPenalty: 0.3,      // EP -30%
    readingPenalty: 0,   // 阅读无惩罚
    adaptSkill: 'narrow_fighting',  // 适应技能
    description: '狭窄'
  },
  [ENVIRONMENT_TYPES.HARSH]: {
    apPenalty: 0.1,      // AP -10%
    epPenalty: 0.1,      // EP -10%
    readingPenalty: 0.2, // 阅读效率 -20%
    adaptSkill: 'survivalist',  // 适应技能
    description: '恶劣'
  },
  [ENVIRONMENT_TYPES.NORMAL]: {
    apPenalty: 0,
    epPenalty: 0,
    readingPenalty: 0,
    adaptSkill: null,
    description: '普通'
  }
}

/**
 * 获取当前位置的环境惩罚
 * @param {String} locationId - 位置ID
 * @param {Object} playerStore - 玩家Store
 * @returns {Object} 惩罚信息
 */
export function getEnvironmentPenalty(locationId, playerStore) {
  const location = LOCATION_CONFIG[locationId]
  if (!location) {
    return getDefaultPenalty()
  }

  const environmentType = location.environment || ENVIRONMENT_TYPES.NORMAL
  const basePenalty = ENVIRONMENT_PENALTIES[environmentType] || ENVIRONMENT_PENALTIES[ENVIRONMENT_TYPES.NORMAL]

  // 应用技能减少惩罚
  const penalty = { ...basePenalty }

  // 夜视技能减少黑暗惩罚
  if (environmentType === ENVIRONMENT_TYPES.DARK) {
    const darkPenaltyReduce = playerStore.globalBonus?.darkPenaltyReduce || 0
    penalty.apPenalty = Math.max(0, penalty.apPenalty * (1 - darkPenaltyReduce / 100))
    penalty.epPenalty = Math.max(0, penalty.epPenalty * (1 - darkPenaltyReduce / 100))
    penalty.readingPenalty = Math.max(0, penalty.readingPenalty * (1 - darkPenaltyReduce / 100))
  }

  return penalty
}

/**
 * 获取默认惩罚（普通环境）
 */
function getDefaultPenalty() {
  return {
    apPenalty: 0,
    epPenalty: 0,
    readingPenalty: 0,
    adaptSkill: null,
    description: '普通'
  }
}

/**
 * 计算AP环境修正
 * @param {String} locationId - 位置ID
 * @param {Object} playerStore - 玩家Store
 * @returns {Number} 修正倍率 (0-1)
 */
export function getAPModifier(locationId, playerStore) {
  const penalty = getEnvironmentPenalty(locationId, playerStore)
  return 1 - penalty.apPenalty
}

/**
 * 计算EP环境修正
 * @param {String} locationId - 位置ID
 * @param {Object} playerStore - 玩家Store
 * @returns {Number} 修正倍率 (0-1)
 */
export function getEPModifier(locationId, playerStore) {
  const penalty = getEnvironmentPenalty(locationId, playerStore)
  return 1 - penalty.epPenalty
}

/**
 * 计算阅读效率修正
 * @param {String} locationId - 位置ID
 * @param {Object} playerStore - 玩家Store
 * @returns {Number} 修正倍率 (0-1)
 */
export function getReadingModifier(locationId, playerStore) {
  const penalty = getEnvironmentPenalty(locationId, playerStore)
  return 1 - penalty.readingPenalty
}

/**
 * 处理环境被动经验
 * 在特定环境中被动获得技能经验
 * @param {Object} gameStore - 游戏Store
 * @param {Object} playerStore - 玩家Store
 * @param {String} locationId - 位置ID
 * @param {Number} deltaTime - 时间增量（秒）
 * @returns {Object} 获得的经验 { skillId: exp }
 */
export function processEnvironmentExp(gameStore, playerStore, locationId, deltaTime = 1) {
  const location = LOCATION_CONFIG[locationId]
  if (!location) return {}

  const environmentType = location.environment || ENVIRONMENT_TYPES.NORMAL
  const penalty = ENVIRONMENT_PENALTIES[environmentType]

  if (!penalty.adaptSkill) {
    return {}
  }

  const adaptSkillId = penalty.adaptSkill
  const skillConfig = SKILL_CONFIG[adaptSkillId]

  if (!skillConfig) {
    return {}
  }

  // 检查技能是否已解锁
  if (!playerStore.skills[adaptSkillId] || !playerStore.skills[adaptSkillId].unlocked) {
    // 检查解锁条件
    if (skillConfig.unlockCondition) {
      const condition = skillConfig.unlockCondition
      if (condition.location === locationId) {
        // 首次进入该环境，解锁技能
        if (!playerStore.skills[adaptSkillId]) {
          playerStore.skills[adaptSkillId] = {
            level: 0,
            exp: 0,
            unlocked: true
          }
          if (gameStore.addLog) {
            gameStore.addLog(`解锁了被动技能: ${skillConfig.name}`, 'system')
          }
        }
      }
    }
    return {}
  }

  // 计算被动经验（每秒获得基础经验）
  const baseExpRate = 0.5  // 每秒0.5经验
  const expGain = baseExpRate * deltaTime

  // 应用阅读速度加成
  const readingSpeedBonus = playerStore.globalBonus?.readingSpeed || 1
  const finalExp = expGain * readingSpeedBonus

  // 添加经验
  playerStore.skills[adaptSkillId].exp += finalExp

  // 检查升级
  const exp = playerStore.skills[adaptSkillId].exp
  const maxExp = skillConfig.expPerLevel(playerStore.skills[adaptSkillId].level + 1)

  if (exp >= maxExp && playerStore.skills[adaptSkillId].level < skillConfig.maxLevel) {
    playerStore.skills[adaptSkillId].level++
    playerStore.skills[adaptSkillId].exp -= maxExp

    if (gameStore.addLog) {
      gameStore.addLog(`${skillConfig.name} 提升到了 Lv.${playerStore.skills[adaptSkillId].level}!`, 'reward')
    }

    // 检查里程碑奖励（需要调用技能系统）
    // TODO: 调用 applyMilestoneBonus
  }

  return { [adaptSkillId]: finalExp }
}

/**
 * 检查位置解锁条件
 * @param {String} locationId - 位置ID
 * @param {Object} playerStore - 玩家Store
 * @returns {Object} { unlocked: boolean, reason: string }
 */
export function checkLocationUnlock(locationId, playerStore) {
  const location = LOCATION_CONFIG[locationId]
  if (!location) {
    return { unlocked: false, reason: '位置不存在' }
  }

  if (!location.unlockCondition) {
    return { unlocked: true, reason: '' }
  }

  const condition = location.unlockCondition

  switch (condition.type) {
    case 'kill':
      // 击杀条件
      const killCount = (playerStore.killCount || {})[condition.target] || 0
      if (killCount < condition.count) {
        return {
          unlocked: false,
          reason: `需要击杀 ${condition.count} 只${getEnemyName(condition.target)} (当前: ${killCount})`
        }
      }
      break

    case 'item':
      // 物品条件
      const hasItem = playerStore.inventory?.some(i => i.id === condition.item)
      if (!hasItem) {
        const itemName = getItemName(condition.item)
        return { unlocked: false, reason: `需要 ${itemName}` }
      }
      break

    case 'level':
      // 等级条件
      const playerLevel = playerStore.level?.current || 1
      if (playerLevel < condition.level) {
        return { unlocked: false, reason: `需要等级 ${condition.level}` }
      }
      break

    case 'skill':
      // 技能条件
      const skill = playerStore.skills[condition.skillId]
      if (!skill || skill.level < condition.level) {
        return { unlocked: false, reason: `需要技能达到指定等级` }
      }
      break

    case 'flag':
      // 标志条件
      if (!playerStore.flags?.[condition.flag]) {
        return { unlocked: false, reason: '需要完成特定事件' }
      }
      break
  }

  return { unlocked: true, reason: '' }
}

/**
 * 获取敌人名称（辅助函数）
 */
function getEnemyName(enemyId) {
  // 简化实现，实际应该从 ENEMY_CONFIG 获取
  const names = {
    wild_dog: '野狗',
    test_boss: '测试Boss'
  }
  return names[enemyId] || enemyId
}

/**
 * 获取物品名称（辅助函数）
 */
function getItemName(itemId) {
  // 简化实现，实际应该从 ITEM_CONFIG 获取
  const names = {
    basement_key: '地下室钥匙',
    old_book: '破旧书籍'
  }
  return names[itemId] || itemId
}

/**
 * 检查位置是否安全
 * @param {String} locationId - 位置ID
 * @returns {Boolean}
 */
export function isSafeLocation(locationId) {
  const location = LOCATION_CONFIG[locationId]
  return location?.type === 'safe'
}

/**
 * 检查位置是否为战斗区域
 * @param {String} locationId - 位置ID
 * @returns {Boolean}
 */
export function isCombatLocation(locationId) {
  const location = LOCATION_CONFIG[locationId]
  return location?.type === 'danger' || location?.type === 'dungeon'
}

/**
 * 获取位置可用的活动
 * @param {String} locationId - 位置ID
 * @returns {Array} 活动列表
 */
export function getLocationActivities(locationId) {
  const location = LOCATION_CONFIG[locationId]
  return location?.activities || []
}

/**
 * 获取位置连接
 * @param {String} locationId - 位置ID
 * @returns {Array} 连接的位置ID列表
 */
export function getLocationConnections(locationId) {
  const location = LOCATION_CONFIG[locationId]
  return location?.connections || []
}

/**
 * 检查位置是否可到达
 * @param {String} fromId - 起始位置ID
 * @param {String} toId - 目标位置ID
 * @param {Object} playerStore - 玩家Store
 * @returns {Object} { reachable: boolean, reason: string }
 */
export function canTravelTo(fromId, toId, playerStore) {
  const fromLocation = LOCATION_CONFIG[fromId]
  if (!fromLocation) {
    return { reachable: false, reason: '当前位置不存在' }
  }

  // 检查是否直接连接
  if (!fromLocation.connections?.includes(toId)) {
    return { reachable: false, reason: '无法直接到达' }
  }

  // 检查目标位置解锁条件
  return checkLocationUnlock(toId, playerStore)
}

/**
 * 计算位置转移时间
 * @param {String} fromId - 起始位置ID
 * @param {String} toId - 目标位置ID
 * @returns {Number} 转移时间（秒）
 */
export function getTravelTime(fromId, toId) {
  // 简化实现：所有位置间转移时间为5秒
  return 5
}

/**
 * 获取环境描述
 * @param {String} locationId - 位置ID
 * @param {Object} playerStore - 玩家Store
 * @returns {String} 环境描述
 */
export function getEnvironmentDescription(locationId, playerStore) {
  const location = LOCATION_CONFIG[locationId]
  if (!location) return ''

  const penalty = getEnvironmentPenalty(locationId, playerStore)
  let description = location.description || ''

  // 添加环境效果描述
  if (location.environment === ENVIRONMENT_TYPES.DARK) {
    const hasNightVision = playerStore.skills.night_vision?.level > 0
    if (!hasNightVision) {
      description += ' [黑暗: AP/EP-20% 阅读效率-50%]'
    } else {
      const reduce = playerStore.globalBonus?.darkPenaltyReduce || 0
      description += ` [黑暗: 惩罚减少${reduce}%]`
    }
  }

  return description
}

/**
 * 获取位置的可敌人列表
 * @param {String} locationId - 位置ID
 * @returns {Array} 敌人ID列表
 */
export function getLocationEnemies(locationId) {
  const location = LOCATION_CONFIG[locationId]
  return location?.enemies || []
}

/**
 * 获取位置的NPC列表
 * @param {String} locationId - 位置ID
 * @returns {Array} NPC ID列表
 */
export function getLocationNPCs(locationId) {
  const location = LOCATION_CONFIG[locationId]
  return location?.npcs || []
}

/**
 * 检查是否有负面状态来自环境
 * @param {String} locationId - 位置ID
 * @param {Object} playerStore - 玩家Store
 * @returns {Array} 负面状态列表
 */
export function getEnvironmentNegativeStatus(locationId, playerStore) {
  const location = LOCATION_CONFIG[locationId]
  if (!location) return []

  const status = []

  // 黑暗环境可能造成精神压力
  if (location.environment === ENVIRONMENT_TYPES.DARK) {
    const hasNightVision = playerStore.skills.night_vision?.level || 0
    if (hasNightVision < 5) {
      status.push({
        type: 'darkness',
        name: '黑暗恐惧',
        effect: '精神逐渐下降',
        severity: hasNightVision > 0 ? 'mild' : 'moderate'
      })
    }
  }

  return status
}

/**
 * 处理环境负面状态效果
 * @param {Object} playerStore - 玩家Store
 * @param {String} locationId - 位置ID
 * @param {Number} deltaTime - 时间增量（秒）
 */
export function processEnvironmentEffects(playerStore, locationId, deltaTime = 1) {
  const location = LOCATION_CONFIG[locationId]
  if (!location) return

  // 黑暗环境的精神压力
  if (location.environment === ENVIRONMENT_TYPES.DARK) {
    const nightVisionLevel = playerStore.skills.night_vision?.level || 0

    // 夜视5级以下会缓慢消耗精神
    if (nightVisionLevel < 5) {
      const sanityDrain = 0.1 * (1 - nightVisionLevel * 0.1) * deltaTime
      playerStore.currentStats.sanity = Math.max(
        0,
        playerStore.currentStats.sanity - sanityDrain
      )
    }
  }

  // 恶劣环境的持续影响
  if (location.environment === ENVIRONMENT_TYPES.HARSH) {
    const survivalistLevel = playerStore.skills.survivalist?.level || 0

    // 生存技能可以减少恶劣环境影响
    if (survivalistLevel < 5) {
      const staminaDrain = 0.2 * (1 - survivalistLevel * 0.1) * deltaTime
      playerStore.currentStats.stamina = Math.max(
        0,
        playerStore.currentStats.stamina - staminaDrain
      )
    }
  }
}