<template>
  <div class="layout">
    <div class="view">
      <form
        v-if="tokenChecked && tokenValid"
        class="reset-form"
        @submit.prevent="submitForm"
        novalidate
      >
        <h2>Set a new password</h2>

        <div class="form-group">
          <label for="password">New password</label>
          <input
            id="password"
            type="password"
            autocomplete="new-password"
            v-model="password"
            :class="{ 'input-error': password && (!isPasswordStrongRef || !passwordsMatch) }"
            required
          />
          <small v-if="password && !isPasswordStrongRef" class="error-message" aria-live="polite">
            Password must be at least 8 characters and contain a letter and a number.
          </small>
        </div>

        <div class="form-group">
          <label for="confirm">Confirm password</label>
          <input
            id="confirm"
            type="password"
            autocomplete="new-password"
            v-model="confirmPassword"
            :class="{ 'input-error': confirmPassword && !passwordsMatch }"
            required
          />
          <small v-if="confirmPassword && !passwordsMatch" class="error-message" aria-live="polite">
            Passwords do not match.
          </small>
        </div>

        <div v-if="errorMsg" class="error-message" style="margin-bottom: 1rem" aria-live="polite">
          {{ errorMsg }}
        </div>
        <div
          v-if="successMsg"
          class="success-message"
          style="margin-bottom: 1rem"
          aria-live="polite"
        >
          {{ successMsg }}
        </div>

        <div class="form-group actions" style="margin-top: 0.4rem">
          <button type="submit" class="btn btn-primary" :disabled="loading || !formValid">
            {{ loading ? 'Resetting…' : 'Reset password' }}
          </button>
        </div>

        <p
          style="
            text-align: center;
            margin-top: 0.8rem;
            color: var(--sub-message-color, #6b7280);
            font-size: 0.95rem;
          "
        >
          Remembered your password?
          <button
            type="button"
            class="btn-link"
            @click="goToLogin"
            style="
              background: none;
              border: none;
              color: var(--btn-primary);
              font-weight: 600;
              cursor: pointer;
              padding: 0;
              margin-left: 6px;
            "
          >
            Sign in
          </button>
        </p>
      </form>
      <div
        v-else-if="tokenChecked && !tokenValid"
        class="error-message"
        aria-live="polite"
        style="margin-top: 2rem"
      >
        {{ errorMsg }}
        <div style="margin-top: 1.2rem">
          <button
            type="button"
            class="btn-link"
            @click="goToLogin"
            style="
              background: none;
              border: none;
              color: var(--btn-primary);
              font-weight: 600;
              cursor: pointer;
              padding: 0;
              margin-left: 6px;
            "
          >
            Sign in
          </button>
        </div>
      </div>
      <div v-else style="margin-top: 2rem; text-align: center">Checking reset link...</div>
    </div>

    <!-- Success Modal -->
    <ModalDialog v-if="showModal" title="Password Reset Successful" @backdrop-click="closeModal">
      <p class="modal-message">
        Your password has been reset successfully. You can now sign in with your new password.
      </p>
      <div class="modal-actions">
        <button @click="goToLogin" class="btn btn-primary">Sign In</button>
      </div>
    </ModalDialog>
  </div>
</template>

<script setup lang="ts">
import { ref, computed, onMounted } from 'vue'
import { useRouter, useRoute } from 'vue-router'
import { isPasswordStrong } from '@/common/api'
import ModalDialog from '@/components/shared/ModalDialog.vue'
import '@/assets/styles.css'

const router = useRouter()
const route = useRoute()

const password = ref('')
const confirmPassword = ref('')
const submitAttempted = ref(false)
const loading = ref(false)
const errorMsg = ref('')
const successMsg = ref('')
const token = ref('')
const tokenValid = ref(false)
const tokenChecked = ref(false)
const showModal = ref(false)

const isPasswordStrongRef = computed(() => isPasswordStrong(password.value))
const passwordsMatch = computed(() => password.value === confirmPassword.value)
const formValid = computed(
  () =>
    password.value && confirmPassword.value && isPasswordStrongRef.value && passwordsMatch.value,
)

onMounted(async () => {
  // Get token from query string
  const raw = route.query.token ?? ''
  token.value = Array.isArray(raw) ? raw[0] : String(raw || '')

  // Validate token with backend
  if (token.value) {
    try {
      const res = await fetch(
        `/api/auth/validate-reset-token?token=${encodeURIComponent(token.value)}`,
      )
      tokenChecked.value = true
      if (res.ok) {
        tokenValid.value = true
      } else {
        const data = await res.json().catch(() => ({}))
        errorMsg.value = data.error || 'This password reset link is invalid or has expired.'
        tokenValid.value = false
        // Redirect to AuthLanding
        router.push({ name: 'AuthLanding' }).catch(() => (window.location.href = '/auth'))
      }
    } catch {
      errorMsg.value = 'Network error. Please try again.'
      tokenValid.value = false
      tokenChecked.value = true
      // Redirect to AuthLanding
      router.push({ name: 'AuthLanding' }).catch(() => (window.location.href = '/auth'))
    }
  } else {
    errorMsg.value = 'No reset token provided.'
    tokenValid.value = false
    tokenChecked.value = true
    // Redirect to AuthLanding
    router.push({ name: 'AuthLanding' }).catch(() => (window.location.href = '/auth'))
  }
})

async function submitForm() {
  submitAttempted.value = true
  errorMsg.value = ''
  successMsg.value = ''

  if (!formValid.value) return
  loading.value = true
  try {
    const res = await fetch('/api/auth/reset-password', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        token: token.value,
        password: password.value,
      }),
    })
    if (!res.ok) {
      let msg = 'Could not reset password.'
      try {
        const data = await res.json()
        if (data && (data.error || data.message)) {
          msg = data.error || data.message
        }
      } catch {
        try {
          const text = await res.text()
          if (text) msg = text
        } catch {}
      }
      errorMsg.value = msg
      return
    }
    // Success: Show modal instead of successMsg
    showModal.value = true
    password.value = ''
    confirmPassword.value = ''
    submitAttempted.value = false
  } catch {
    errorMsg.value = 'Network error. Please try again.'
  } finally {
    loading.value = false
  }
}

function closeModal() {
  showModal.value = false
}

async function goToLogin() {
  await router.push({ name: 'Login' }).catch(() => (window.location.href = '/auth/login'))
}
</script>

<style scoped>
.view {
  max-width: 420px;
  margin: 0 auto;
  background: var(--edit-view-bg, #fff);
  border-radius: 14px;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
  padding: 2.2rem 2.2rem 1.5rem 2.2rem;
}
.view h2 {
  text-align: center;
  margin-bottom: 1.5rem;
  color: var(--form-heading);
}

.reset-form {
  background: transparent;
  box-shadow: none;
  padding: 0;
  border: none;
}

/* reuse edit-forms form-group styles */
.form-group {
  margin-bottom: 1.5rem;
}

.form-group label {
  display: block;
  color: var(--form-label, #444);
  font-weight: 600;
}
.form-group input,
.form-group input[type='email'],
.form-group input[type='password'] {
  display: block;
  width: 100%;
  margin-top: 0.4rem;
  padding: 0.6rem;
  border-radius: 7px;
  border: 1px solid var(--form-input-border, #e6e6e6);
  font-size: 1rem;
  background: var(--form-input-bg, #fff);
  box-sizing: border-box;
}

@media (max-width: 520px) {
  .reset-form {
    padding: 1rem;
    border-radius: 10px;
  }
}

.actions {
  display: flex;
  gap: 3rem;
  justify-content: center;
  margin-top: 0.5rem;
  margin-bottom: 0.4rem;
}
.actions .btn {
  padding: 1rem 2.2rem;
  font-weight: 700;
  font-size: 1.25rem;
  min-width: 120px;
}
</style>
