import { useState, useEffect, useRef } from 'react';
import { supabase } from '../lib/supabase';
import { serviceTypes } from '../data/mockData';
import FileAttachment from './FileAttachment';
import { addDaysToDateOnly, getTodayDateOnlyEST } from '../lib/dates';

const defaultDeadline = () => addDaysToDateOnly(getTodayDateOnlyEST(), 3);
const modalLabelStyle = { fontSize: 11, fontWeight: 500, color: 'var(--text-secondary)', textTransform: 'uppercase', letterSpacing: 0.8, marginBottom: 6 };
const modalInputStyle = { fontSize: 13, padding: '0 5px', textAlign: 'left', lineHeight: 1 };
const modalTextAreaStyle = { ...modalInputStyle, minHeight: 100, padding: '8px 5px', lineHeight: 1.4 };
const modalActionButtonStyle = { width: 132, justifyContent: 'center', flex: '0 0 132px' };
const emptyForm = (companyId = '') => ({
  companyId,
  project: '',
  serviceType: '',
  signFamily: '',
  title: '',
  deadline: defaultDeadline(),
  description: '',
  isHot: false,
  requestedBy: '',
});

// Props:
//   companies        [{id, name}]  — all selectable companies
//   currentUser      {id, name}    — logged-in team member (added to requester list as "You")
//   showRequester    bool          — true for team (submitting on behalf of client)
//   onSubmit         async (formData, files, existingProjects) => void  — throw to show error
//   onCancel         () => void    — optional; shows Cancel button when provided
//   saving           bool
//   error            string
//   submitLabel      string
//   initialCompanyId string        — pre-selected company (client with 1 company)
export default function RequestForm({
  companies = [],
  currentUser = null,
  showRequester = false,
  onSubmit,
  onCancel = null,
  saving = false,
  error = '',
  submitLabel = 'Submit Request',
  initialCompanyId = '',
  initialValues = null,
  lockedFields = [],
}) {
  const [form, setForm] = useState(() => ({
    ...emptyForm(initialCompanyId),
    requestedBy: showRequester ? (currentUser?.id || '') : '',
    ...(initialValues || {}),
  }));
  const prevCompanyIdRef = useRef(initialValues?.companyId || initialCompanyId || null);
  const [files, setFiles] = useState([]);
  const [existingProjects, setExistingProjects] = useState([]);
  const [customProjects, setCustomProjects] = useState([]);
  const [isTypingProject, setIsTypingProject] = useState(false);
  const [newProjectName, setNewProjectName] = useState('');
  const [companyUsers, setCompanyUsers] = useState([]);
  const [signFamilies, setSignFamilies] = useState([]);
  const [signCount, setSignCount] = useState('');
  const [signs, setSigns] = useState([]);
  const [localError, setLocalError] = useState('');

  const usesSignFields = form.serviceType === 'Brand Book';

  useEffect(() => {
    supabase.from('sign_families').select('name').order('sort_order').then(({ data }) => setSignFamilies((data || []).map(r => r.name)));
  }, []);

  useEffect(() => {
    if (!usesSignFields) { setSignCount(''); setSigns([]); }
  }, [usesSignFields]);

  useEffect(() => {
    const n = Math.max(0, parseInt(signCount) || 0);
    setSigns(prev => {
      if (n < prev.length) return prev.slice(0, n);
      if (n > prev.length) {
        const extra = Array.from({ length: n - prev.length }, () => ({ id: crypto.randomUUID(), signName: '', signFamily: '' }));
        return [...prev, ...extra];
      }
      return prev;
    });
  }, [signCount]);

  const companyId = form.companyId || initialCompanyId;

  // Single-company user: lock selection to their one company.
  useEffect(() => {
    if (companies.length === 1 && !form.companyId) {
      setForm(f => ({ ...f, companyId: companies[0].id }));
    }
  }, [companies, form.companyId]);

  useEffect(() => {
    if (!companyId) { setExistingProjects([]); setCompanyUsers([]); return; }
    Promise.all([
      supabase.from('projects').select('id, name').eq('company_id', companyId).order('name'),
      showRequester
        ? Promise.all([
            supabase.from('profiles').select('id, name, email').eq('company_id', companyId).eq('role', 'client'),
            supabase.from('company_members').select('profile:profiles(id, name, email, role)').eq('company_id', companyId),
          ])
        : Promise.resolve(null),
    ]).then(([projectsRes, usersData]) => {
      setExistingProjects(projectsRes.data || []);
      if (usersData) {
        const [directRes, membersRes] = usersData;
        const direct = (directRes.data || []);
        const fromMembers = (membersRes.data || []).map(m => m.profile).filter(p => p?.role === 'client');
        const seen = new Set();
        const merged = [...direct, ...fromMembers].filter(u => {
          if (!u?.id || seen.has(u.id)) return false;
          seen.add(u.id);
          return true;
        }).sort((a, b) => (a.name || '').localeCompare(b.name || ''));
        setCompanyUsers(merged);
      }
    });
    if (companyId !== prevCompanyIdRef.current) {
      setForm(f => ({ ...f, project: '', requestedBy: '' }));
      setCustomProjects([]);
      setIsTypingProject(false);
      setNewProjectName('');
    }
    prevCompanyIdRef.current = companyId;
  }, [companyId]); // eslint-disable-line react-hooks/exhaustive-deps

  const set = (field) => (e) => {
    if (localError) setLocalError('');
    setForm(f => ({ ...f, [field]: e.target.value }));
  };

  const setSign = (id, field, value) => {
    if (localError) setLocalError('');
    setSigns(prev => prev.map(s => s.id === id ? { ...s, [field]: value } : s));
  };

  const allProjectNames = [
    ...existingProjects.map(p => p.name),
    ...customProjects.filter(name => !existingProjects.some(p => p.name === name)),
  ];

  const handleProjectSelect = (e) => {
    if (e.target.value === '__new__') {
      setIsTypingProject(true);
      setForm(f => ({ ...f, project: '' }));
    } else {
      setForm(f => ({ ...f, project: e.target.value }));
    }
  };

  const handleAddProject = () => {
    const name = newProjectName.trim();
    if (!name) return;
    if (!customProjects.includes(name) && !existingProjects.some(p => p.name === name)) {
      setCustomProjects(prev => [...prev, name]);
    }
    setForm(f => ({ ...f, project: name }));
    setIsTypingProject(false);
    setNewProjectName('');
  };

  const showCompanySelect = companies.length > 1 || showRequester;
  const requesterOptions = [
    ...(currentUser ? [{ id: currentUser.id, name: `${currentUser.name} (You)` }] : []),
    ...companyUsers.filter(u => u.id !== currentUser?.id),
  ];

  const handleSubmit = (e) => {
    e.preventDefault();
    setLocalError('');
    const selectedRequester = showRequester
      ? requesterOptions.find(option => option.id === form.requestedBy) || null
      : null;
    const requestedBy = showRequester
      ? (selectedRequester?.id || '')
      : (currentUser?.id || '');
    const requestedByName = showRequester
      ? ((selectedRequester?.name || '').replace(/\s+\(You\)$/, '') || '')
      : (currentUser?.name || '');
    let normalizedSignCount = null;
    let normalizedSigns = [];

    if (usesSignFields) {
      normalizedSignCount = parseInt(signCount, 10) || null;
      const formData = new FormData(e.currentTarget);
      normalizedSigns = Array.from({ length: normalizedSignCount || 0 }, (_, index) => {
        const stateSign = signs[index] || {};
        const domValue = formData.get(`sign_info_${index + 1}`);
        const signName = typeof domValue === 'string'
          ? domValue.trim()
          : String(stateSign.signName || '').trim();
        return {
          id: stateSign.id || `sign-${index + 1}`,
          signName,
          signFamily: stateSign.signFamily || '',
        };
      }).filter(sign => sign.signName || sign.signFamily);

      if ((normalizedSignCount || 0) > 0 && normalizedSigns.length !== normalizedSignCount) {
        setLocalError('Please fill in the sign information for each sign before submitting.');
        return;
      }
    }

    onSubmit(
      {
        ...form,
        companyId,
        requestedBy,
        requestedByName,
        signCount: usesSignFields ? normalizedSignCount : null,
        signs: usesSignFields ? normalizedSigns : [],
      },
      files,
      existingProjects
    );
  };

  return (
    <form onSubmit={handleSubmit}>
      {/* Row 1: Company + Project */}
      <div className="grid-2">
        {lockedFields.includes('company') ? (
          <div className="form-group">
            <label style={modalLabelStyle}>Company</label>
            <input value={companies.find(c => c.id === companyId)?.name || companyId} disabled style={{ ...modalInputStyle, opacity: 0.5, cursor: 'not-allowed' }} />
          </div>
        ) : showCompanySelect ? (
          <div className="form-group">
            <label style={modalLabelStyle}>Company *</label>
            <select value={form.companyId} onChange={e => setForm(f => ({ ...f, companyId: e.target.value }))} required style={modalInputStyle}>
              <option value="">Select company...</option>
              {companies.map(co => <option key={co.id} value={co.id}>{co.name}</option>)}
            </select>
          </div>
        ) : companies.length === 1 ? (
          <div className="form-group">
            <label style={modalLabelStyle}>Company</label>
            <input value={companies[0].name} disabled style={{ ...modalInputStyle, opacity: 0.5, cursor: 'not-allowed' }} />
          </div>
        ) : <div />}
        <div className="form-group">
          <label style={modalLabelStyle}>Client {!lockedFields.includes('project') && '*'}</label>
          {lockedFields.includes('project') ? (
            <input value={form.project} disabled style={{ ...modalInputStyle, opacity: 0.5, cursor: 'not-allowed' }} />
          ) : isTypingProject ? (
            <div style={{ display: 'flex', gap: 8 }}>
              <input type="text" placeholder="Enter client name..." value={newProjectName} onChange={e => setNewProjectName(e.target.value)} onKeyDown={e => { if (e.key === 'Enter') { e.preventDefault(); handleAddProject(); } }} autoFocus style={{ ...modalInputStyle, flex: 1 }} />
              <button type="button" className="btn btn-outline" onClick={handleAddProject} disabled={!newProjectName.trim()}>Add</button>
              <button type="button" className="btn btn-outline" onClick={() => { setIsTypingProject(false); setNewProjectName(''); }}>Cancel</button>
            </div>
          ) : (
            <select value={form.project} onChange={handleProjectSelect} required disabled={showCompanySelect && !companyId} style={modalInputStyle}>
              <option value="">{showCompanySelect && !companyId ? 'Select company first' : 'Select a project...'}</option>
              {allProjectNames.map(name => <option key={name} value={name}>{name}</option>)}
              {(!showCompanySelect || companyId) && <option value="__new__">＋ Create new project...</option>}
            </select>
          )}
        </div>
      </div>

      {/* Row 2: Service Type + Desired Deadline */}
      <div className="grid-2">
        <div className="form-group">
          <label style={modalLabelStyle}>Service Type *</label>
          <select value={form.serviceType} onChange={set('serviceType')} required style={modalInputStyle}>
            <option value="">Select service...</option>
            {serviceTypes.map(s => <option key={s} value={s}>{s}</option>)}
          </select>
        </div>
        <div className="form-group">
          <label style={modalLabelStyle}>Desired Deadline</label>
          <input type="date" value={form.deadline} onChange={set('deadline')} style={modalInputStyle} />
        </div>
      </div>

      {showRequester && (
        <div className="form-group">
          <label style={modalLabelStyle}>Requested By *</label>
          <select
            value={form.requestedBy}
            onChange={set('requestedBy')}
            required
            disabled={!companyId}
            style={modalInputStyle}
          >
            <option value="">{companyId ? 'Select requester...' : 'Select company first'}</option>
            {requesterOptions.map(user => (
              <option key={user.id} value={user.id}>{user.name}</option>
            ))}
          </select>
        </div>
      )}

      {/* Row 3: Title/Location + Mark as Hot inline */}
      <div style={{ display: 'grid', gridTemplateColumns: '1fr auto', gap: 12, alignItems: 'end', marginBottom: 16 }}>
        <div className="form-group" style={{ marginBottom: 0 }}>
          <label style={modalLabelStyle}>Title / Location *</label>
          <input type="text" placeholder="e.g. City, State or Site Name" value={form.title} onChange={set('title')} required style={modalInputStyle} />
        </div>
        <label style={{ ...modalLabelStyle, display: 'flex', alignItems: 'center', gap: 8, cursor: 'pointer', marginBottom: 4, whiteSpace: 'nowrap' }}>
          <input type="checkbox" checked={form.isHot} onChange={e => setForm(f => ({ ...f, isHot: e.target.checked }))} />
          <span>Mark as Hot</span>
        </label>
      </div>

      {usesSignFields && (
        <div className="form-group">
          <label style={modalLabelStyle}>Sign Count *</label>
          <input
            type="number"
            min="1"
            max="50"
            placeholder="How many signs?"
            value={signCount}
            onChange={e => setSignCount(e.target.value)}
            required
            style={{ ...modalInputStyle, width: '100%' }}
          />
        </div>
      )}

      {usesSignFields && signs.length > 0 && (
        <div style={{ display: 'flex', flexDirection: 'column', gap: 8, marginBottom: 16 }}>
          {signs.map((sign, i) => (
            <div key={sign.id} style={{ border: '1px solid var(--border)', borderRadius: 6, padding: '10px 12px' }}>
              <div style={{ ...modalLabelStyle, marginBottom: 8 }}>Sign {i + 1}</div>
              <div className="form-group" style={{ marginBottom: 0 }}>
                <label style={modalLabelStyle}>Sign Information *</label>
                <input
                  type="text"
                  name={`sign_info_${i + 1}`}
                  placeholder="e.g. Main Entry, Drive Thru"
                  value={sign.signName}
                  onChange={e => setSign(sign.id, 'signName', e.target.value)}
                  required
                  style={modalInputStyle}
                />
              </div>
            </div>
          ))}
        </div>
      )}

      <div className="form-group">
        <label style={modalLabelStyle}>{usesSignFields ? 'Notes' : 'Description'} *</label>
        <textarea placeholder="Notes on the request..." value={form.description} onChange={set('description')} style={modalTextAreaStyle} required />
      </div>

      <FileAttachment files={files} onChange={setFiles} />

      {(localError || error) && <div style={{ fontSize: 13, color: 'var(--danger)', marginBottom: 12 }}>⚠ {localError || error}</div>}

      <div className="action-buttons modal-action-row" style={{ justifyContent: 'flex-end' }}>
        <button type="submit" className="btn btn-outline" disabled={saving} style={modalActionButtonStyle}>
          {saving ? 'Submitting...' : submitLabel}
        </button>
        {onCancel && <button type="button" className="btn btn-outline" onClick={onCancel} style={modalActionButtonStyle}>Cancel</button>}
      </div>
    </form>
  );
}