from flask_wtf import FlaskForm
from wtforms import SelectField, StringField, SubmitField, TextAreaField
from wtforms.fields import DateTimeLocalField
from wtforms.validators import DataRequired, Length, Optional, ValidationError

from .models import TASK_PRIORITIES, TASK_STATUSES


STATUS_LABELS = {
    "not_started": "Not started",
    "in_progress": "In progress",
    "done": "Done",
}
PRIORITY_LABELS = {
    "urgent": "Urgent",
    "important": "Important",
    "normal": "Normal",
}


def not_blank(_form: FlaskForm, field: StringField) -> None:
    if not field.data or not field.data.strip():
        raise ValidationError("This field cannot be blank.")


class TaskForm(FlaskForm):
    title = StringField(
        "Task title",
        validators=[DataRequired(), not_blank, Length(max=200)],
    )
    description = TextAreaField(
        "Notes",
        validators=[Optional(), Length(max=5000)],
    )
    status = SelectField(
        "Status",
        choices=[(value, STATUS_LABELS[value]) for value in TASK_STATUSES],
        default="not_started",
    )
    priority = SelectField(
        "Priority",
        choices=[(value, PRIORITY_LABELS[value]) for value in TASK_PRIORITIES],
        default="normal",
    )
    due_date = DateTimeLocalField(
        "Due date and time",
        format="%Y-%m-%dT%H:%M",
        validators=[Optional()],
    )
    submit = SubmitField("Save task")


class SubtaskForm(FlaskForm):
    title = StringField(
        "Next small step",
        validators=[DataRequired(), not_blank, Length(max=100)],
    )
    submit = SubmitField("Add step")


class ActionForm(FlaskForm):
    submit = SubmitField()