import { useMemo, useState } from 'react';
import {
  INJURY_TRACKERS,
  RPE_CRITERIA,
  TRACKED_GRADE_SCALE,
  capGradeAtMax,
  getGradeScore,
} from '../utils/weekUtils';
import './ClimbForm.css';

const SESSION_TYPE_OPTIONS = [
  { value: 'lead', label: 'Lead' },
  { value: 'bouldering', label: 'Bouldering' },
];

function buildEmptyPainInputs() {
  return Object.fromEntries(
    INJURY_TRACKERS.flatMap((tracker) => [
      [`${tracker.key}_during`, ''],
      [`${tracker.key}_after`, ''],
    ])
  );
}

function ClimbForm({ onAddSession }) {
  const today = new Date().toISOString().split('T')[0];
  const [date, setDate] = useState(today);
  const [sessionType, setSessionType] = useState('bouldering');
  const [routesCount, setRoutesCount] = useState('');
  const [maxGrade, setMaxGrade] = useState('');
  const [rpe, setRpe] = useState(5);
  const [notes, setNotes] = useState('');
  const [painInputs, setPainInputs] = useState(() => buildEmptyPainInputs());

  const selectedCriteria = useMemo(() => RPE_CRITERIA[rpe] || RPE_CRITERIA[5], [rpe]);

  function handleSubmit(event) {
    event.preventDefault();

    const routes = parseInt(routesCount, 10);
    const parsedRpe = parseInt(rpe, 10);
    const normalizedMaxGrade = capGradeAtMax(maxGrade);
    const maxGradeScore = getGradeScore(normalizedMaxGrade);
    const leftElbowDuring =
      painInputs.left_elbow_during === '' ? null : Number(painInputs.left_elbow_during);
    const leftElbowAfter =
      painInputs.left_elbow_after === '' ? null : Number(painInputs.left_elbow_after);
    const rightShoulderDuring =
      painInputs.right_shoulder_during === '' ? null : Number(painInputs.right_shoulder_during);
    const rightShoulderAfter =
      painInputs.right_shoulder_after === '' ? null : Number(painInputs.right_shoulder_after);

    if (
      !date ||
      Number.isNaN(routes) ||
      routes <= 0 ||
      Number.isNaN(parsedRpe) ||
      parsedRpe < 1 ||
      parsedRpe > 10 ||
      !normalizedMaxGrade ||
      maxGradeScore == null ||
      (leftElbowDuring != null && (Number.isNaN(leftElbowDuring) || leftElbowDuring < 0 || leftElbowDuring > 10)) ||
      (leftElbowAfter != null && (Number.isNaN(leftElbowAfter) || leftElbowAfter < 0 || leftElbowAfter > 10)) ||
      (rightShoulderDuring != null && (Number.isNaN(rightShoulderDuring) || rightShoulderDuring < 0 || rightShoulderDuring > 10)) ||
      (rightShoulderAfter != null && (Number.isNaN(rightShoulderAfter) || rightShoulderAfter < 0 || rightShoulderAfter > 10))
    ) {
      return;
    }

    onAddSession({
      date,
      session_type: sessionType,
      routes_count: routes,
      max_grade: normalizedMaxGrade,
      rpe: parsedRpe,
      left_elbow_during: leftElbowDuring,
      left_elbow_after: leftElbowAfter,
      right_shoulder_during: rightShoulderDuring,
      right_shoulder_after: rightShoulderAfter,
      notes: notes.trim(),
    });

    setRoutesCount('');
    setMaxGrade('');
    setRpe(5);
    setNotes('');
    setPainInputs(buildEmptyPainInputs());
  }

  return (
    <form className="climb-form card" onSubmit={handleSubmit}>
      <h2>Log a Session</h2>

      <div className="form-group">
        <label htmlFor="climb-date">Date</label>
        <input
          id="climb-date"
          type="date"
          value={date}
          onChange={(event) => setDate(event.target.value)}
          required
        />
      </div>

      <div className="form-group">
        <label htmlFor="session-type">Session Type</label>
        <select
          id="session-type"
          value={sessionType}
          onChange={(event) => setSessionType(event.target.value)}
        >
          {SESSION_TYPE_OPTIONS.map((option) => (
            <option key={option.value} value={option.value}>
              {option.label}
            </option>
          ))}
        </select>
      </div>

      <div className="form-group">
        <label htmlFor="route-count">Routes Completed</label>
        <input
          id="route-count"
          type="number"
          min="1"
          step="1"
          placeholder="e.g. 8"
          value={routesCount}
          onChange={(event) => setRoutesCount(event.target.value)}
          required
        />
      </div>

      <div className="form-group">
        <label htmlFor="max-grade">Max Grade Sent</label>
        <input
          id="max-grade"
          type="text"
          placeholder="e.g. 6B+ (max 7B)"
          value={maxGrade}
          onChange={(event) => setMaxGrade(event.target.value)}
          onBlur={() => setMaxGrade((prev) => capGradeAtMax(prev))}
          list="grade-scale-list"
          required
        />
        <datalist id="grade-scale-list">
          {TRACKED_GRADE_SCALE.map((grade) => (
            <option key={grade} value={grade} />
          ))}
        </datalist>
      </div>

      <div className="form-group">
        <label htmlFor="session-rpe">RPE: <strong>{rpe}</strong>/10</label>
        <input
          id="session-rpe"
          type="range"
          min="1"
          max="10"
          step="1"
          value={rpe}
          onChange={(event) => setRpe(Number(event.target.value))}
        />
        <div className="rpe-labels">
          <span>Very easy</span>
          <span>Absolute limit</span>
        </div>
        <div className="rpe-panel">
          <span className="rpe-value">{selectedCriteria.intensity}</span>
          <div className="rpe-criteria-grid">
            <span>Grades</span>
            <span>{selectedCriteria.grades}</span>
            <span>Pump</span>
            <span>{selectedCriteria.pump_level || '—'}</span>
            <span>Suggested Session</span>
            <span>{selectedCriteria.suggested_session}</span>
          </div>
        </div>
      </div>

      <div className="form-group">
        <label htmlFor="session-notes">Notes</label>
        <textarea
          id="session-notes"
          rows="3"
          placeholder="Any beta, fatigue notes, or highlights..."
          value={notes}
          onChange={(event) => setNotes(event.target.value)}
        />
      </div>

      <div className="form-group">
        <label>Injury Tracker (Optional, 0-10)</label>
        <div className="injury-input-grid">
          {INJURY_TRACKERS.map((tracker) => (
            <div key={tracker.key} className="injury-input-item">
              <span className="injury-item-title">{tracker.label}</span>
              <div className="injury-phase-row">
                <label htmlFor={`${tracker.key}_during`}>During</label>
                <input
                  id={`${tracker.key}_during`}
                  type="number"
                  min="0"
                  max="10"
                  step="1"
                  placeholder="0-10"
                  value={painInputs[`${tracker.key}_during`]}
                  onChange={(event) =>
                    setPainInputs((prev) => ({ ...prev, [`${tracker.key}_during`]: event.target.value }))
                  }
                />
              </div>
              <div className="injury-phase-row">
                <label htmlFor={`${tracker.key}_after`}>After</label>
                <input
                  id={`${tracker.key}_after`}
                  type="number"
                  min="0"
                  max="10"
                  step="1"
                  placeholder="0-10"
                  value={painInputs[`${tracker.key}_after`]}
                  onChange={(event) =>
                    setPainInputs((prev) => ({ ...prev, [`${tracker.key}_after`]: event.target.value }))
                  }
                />
              </div>
            </div>
          ))}
        </div>
      </div>

      <button type="submit" className="btn-primary">Add Session</button>
    </form>
  );
}

export default ClimbForm;