import { describe, expect, test } from '@jest/globals'
import { renderText, TextSource } from './renderableText'
import { forbiddenRNG } from './random'

const source: TextSource = {
    empty: '',
    emptyList: [],
    example: 'basic string value',
    singletonList: ['singleton value'],
    singleWeightedItem: [{ wt: 5, v: 'weighted item' }],
    nestedItem: [[[['layered value']]]],
    nestedWeightedItem: [[{ wt: 5, v: [[['innermost text']]] }]],
}

describe('renderText', () => {
    test.each<[string, string, string]>([
        ['returns blank string for blank string', '', ''],
        ['returns constant string for no-substitution string', 'candy', 'candy'],
        ['does not replace empty brackets', '{{}}', '{{}}'],
        ['does not replace escaped brackets', '\\{{empty}}', '{{empty}}'],
        ['does not replace half started brackets', '{{  empty', '{{  empty'],
        ['does not replace brackets without only word characters inside', '{{ ??? }}', '{{ ??? }}'],
        ['escapes backslash and replaces brackets after', '\\\\{{empty}}', '\\'],
        ['replaces empty reference with empty value', '{{empty}}', ''],
        ['replaces empty list reference with empty value', '{{emptyList}}', ''],
        ['replaces string reference with value', '{{example}}', 'basic string value'],
        ['replaces singleton list reference with value', '{{singletonList}}', 'singleton value'],
        ['replaces singleton list reference with weighted value', '{{singleWeightedItem}}', 'weighted item'],
        ['replaces multilevel singleton list reference with inner value', '{{nestedItem}}', 'layered value'],
        [
            'replaces multilevel singleton list reference through weighted item with inner value',
            '{{nestedWeightedItem}}',
            'innermost text',
        ],
    ])(' %s (%j -> %j)', (caseName, input, result) => {
        expect(renderText(input, source, forbiddenRNG)).toEqual(result)
    })

    test.each<[string, string]>([
        ['forbids \\ not followed by { or \\', '\\c'],
        ['forbids reference to nonexistent value', '{{ nonexistentKey }}'],
    ])(' %s (%j -> throws)', (caseName, input) => {
        expect(() => renderText(input, source, forbiddenRNG)).toThrow()
    })
})