import { applyEffect } from '../src/engine/effectApplier.js';

function assert(cond, msg) {
  if (!cond) throw new Error(msg);
}

function createState() {
  return {
    day: 5,
    year: 1,
    age: 10,
    alive: true,
    money: 0,
    stats: { body: 0, wisdom: 0, charm: 0, destiny: 0, business: 0, intelligence: 0 },
    careers: {},
    shopItems: {},
    activeBuffs: {},
    artifacts: {},
    worldFlags: {},
    logs: [],
  };
}

// === addMoney ===
{
  const state = createState();
  applyEffect({ type: 'addMoney', value: 100 }, state);
  assert(state.money === 100, 'addMoney should add to money');
}
{
  const state = createState();
  state.money = 50;
  applyEffect({ type: 'addMoney', value: 25 }, state);
  assert(state.money === 75, 'addMoney should add to existing money');
}

// === addStat ===
{
  const state = createState();
  applyEffect({ type: 'addStat', stat: 'body', value: 5 }, state);
  assert(state.stats.body === 5, 'addStat should add to stat');
}
{
  const state = createState();
  state.stats.body = 10;
  applyEffect({ type: 'addStat', stat: 'body', value: 3 }, state);
  assert(state.stats.body === 13, 'addStat should add to existing stat');
}

// === setStat ===
{
  const state = createState();
  applyEffect({ type: 'setStat', stat: 'wisdom', value: 20 }, state);
  assert(state.stats.wisdom === 20, 'setStat should set stat to value');
}
{
  const state = createState();
  state.stats.wisdom = 50;
  applyEffect({ type: 'setStat', stat: 'wisdom', value: 10 }, state);
  assert(state.stats.wisdom === 10, 'setStat should overwrite existing stat');
}

// === setFlag ===
{
  const state = createState();
  applyEffect({ type: 'setFlag', flag: 'met_taoist', value: true }, state);
  assert(state.worldFlags.met_taoist === true, 'setFlag should set flag');
}
{
  const state = createState();
  state.worldFlags.met_taoist = true;
  applyEffect({ type: 'setFlag', flag: 'met_taoist', value: false }, state);
  assert(state.worldFlags.met_taoist === false, 'setFlag should overwrite flag');
}

// === unlockCareer ===
{
  const state = createState();
  applyEffect({ type: 'unlockCareer', careerId: 'student' }, state);
  assert(state.careers.student !== undefined, 'unlockCareer should create career');
  assert(state.careers.student.level === 0, 'unlockCareer should set level to 0');
  assert(state.careers.student.exp === 0, 'unlockCareer should set exp to 0');
}
{
  const state = createState();
  state.careers.student = { level: 5, exp: 100 };
  applyEffect({ type: 'unlockCareer', careerId: 'student' }, state);
  assert(state.careers.student.level === 5, 'unlockCareer should not overwrite existing career');
  assert(state.careers.student.exp === 100, 'unlockCareer should not overwrite existing career exp');
}

// === addExp ===
{
  const state = createState();
  applyEffect({ type: 'addExp', careerId: 'student', value: 50 }, state);
  assert(state.careers.student !== undefined, 'addExp should create career if missing');
  assert(state.careers.student.exp === 50, 'addExp should add exp');
}
{
  const state = createState();
  state.careers.student = { level: 1, exp: 10 };
  applyEffect({ type: 'addExp', careerId: 'student', value: 20 }, state);
  assert(state.careers.student.exp === 30, 'addExp should add to existing exp');
}

// === addItem ===
{
  const state = createState();
  applyEffect({ type: 'addItem', itemId: 'taoist_license' }, state);
  assert(state.shopItems.taoist_license === 1, 'addItem should add item');
}
{
  const state = createState();
  state.shopItems.taoist_license = 2;
  applyEffect({ type: 'addItem', itemId: 'taoist_license' }, state);
  assert(state.shopItems.taoist_license === 3, 'addItem should increment existing item');
}

// === addBuff ===
{
  const state = createState();
  applyEffect({ type: 'addBuff', buffId: 'blessing', duration: 10 }, state);
  assert(state.activeBuffs.blessing !== undefined, 'addBuff should add buff');
  assert(state.activeBuffs.blessing.expiresDay === 15, 'addBuff should calculate expiresDay');
}
{
  const state = createState();
  applyEffect({ type: 'addBuff', buffId: 'curse', duration: -1 }, state);
  assert(state.activeBuffs.curse !== undefined, 'addBuff should add permanent buff');
  assert(state.activeBuffs.curse.expiresDay === -1, 'addBuff should set expiresDay to -1 for permanent');
}

// === upgradeArtifact ===
{
  const state = createState();
  applyEffect({ type: 'upgradeArtifact', artifactId: 'immortal_sword' }, state);
  assert(state.artifacts.immortal_sword === 1, 'upgradeArtifact should add artifact');
}
{
  const state = createState();
  state.artifacts.immortal_sword = 2;
  applyEffect({ type: 'upgradeArtifact', artifactId: 'immortal_sword' }, state);
  assert(state.artifacts.immortal_sword === 3, 'upgradeArtifact should increment existing artifact');
}

// === addLog ===
{
  const state = createState();
  applyEffect({ type: 'addLog', text: 'Test log entry' }, state);
  assert(state.logs.length === 1, 'addLog should add log entry');
  assert(state.logs[0].text === 'Test log entry', 'addLog should set text');
  assert(state.logs[0].day === 5, 'addLog should set day');
  assert(state.logs[0].year === 1, 'addLog should set year');
  assert(state.logs[0].age === 10, 'addLog should set age');
  assert(state.logs[0].type === 'normal', 'addLog should default type to normal');
  assert(typeof state.logs[0].timestamp === 'number', 'addLog should set timestamp');
}
{
  const state = createState();
  applyEffect({ type: 'addLog', text: 'First' }, state);
  applyEffect({ type: 'addLog', text: 'Second' }, state);
  assert(state.logs.length === 2, 'addLog should add multiple entries');
  assert(state.logs[0].text === 'Second', 'addLog should add newest to front');
  assert(state.logs[1].text === 'First', 'addLog should keep older entries at back');
}
{
  const state = createState();
  for (let i = 0; i < 510; i++) {
    applyEffect({ type: 'addLog', text: `Log ${i}` }, state);
  }
  assert(state.logs.length === 500, 'addLog should cap at 500 entries');
  assert(state.logs[0].text === 'Log 509', 'addLog should keep newest entries');
}

// === die ===
{
  const state = createState();
  applyEffect({ type: 'die', reason: 'old_age' }, state);
  assert(state.alive === false, 'die should set alive to false');
  assert(state.deathReason === 'old_age', 'die should set deathReason');
}

// === edge cases ===
{
  const state = createState();
  applyEffect(null, state);
  assert(state.money === 0, 'null effect should not modify state');
}
{
  const state = createState();
  applyEffect({}, state);
  assert(state.money === 0, 'empty effect should not modify state');
}
{
  const state = createState();
  applyEffect({ type: 'unknownEffect' }, state);
  assert(state.money === 0, 'unknown effect should not modify state');
}

console.log('All effectApplier tests PASS');