<?php

use Illuminate\Support\Facades\File;
use Illuminate\Support\Str;

/**
 * The hue of a #rrggbb colour, in degrees: what harmonisation moves.
 */
function schemeHue(string $hex): float
{
    [$r, $g, $b] = array_map(fn (string $channel): float => hexdec($channel) / 255, str_split(ltrim($hex, '#'), 2));
    $chroma = max($r, $g, $b) - min($r, $g, $b);

    if ($chroma === 0.0) {
        return 0.0;
    }

    $sector = match (max($r, $g, $b)) {
        $r => fmod(($g - $b) / $chroma, 6),
        $g => (($b - $r) / $chroma) + 2,
        default => (($r - $g) / $chroma) + 4,
    };

    return fmod(($sector * 60) + 360, 360);
}

/**
 * How far apart two colours are on the hue circle, the short way round.
 */
function schemeHueDistance(string $one, string $other): float
{
    $apart = abs(schemeHue($one) - schemeHue($other));

    return min($apart, 360 - $apart);
}

beforeEach(function () {
    $this->stylesheet = sys_get_temp_dir().'/material-scheme-'.Str::random(8).'.css';
    $this->data = Str::replaceLast('.css', '.json', $this->stylesheet);
});

afterEach(function () {
    File::delete([$this->stylesheet, $this->data]);
});

it('writes the scheme as a stylesheet and as data', function () {
    $this->artisan('material:scheme', ['seed' => '#4F46E5', '--output' => $this->stylesheet])
        ->assertSuccessful();

    $scheme = json_decode(File::get($this->data), true);
    $stylesheet = File::get($this->stylesheet);

    expect($scheme)
        ->seed->toBe('#4f46e5')
        ->variant->toBe('tonal-spot')
        ->spec->toBe('2025')
        ->harmonize->toBeFalse()
        ->and($scheme['contrast']['standard'])->toBe(0)
        ->and(array_keys($scheme['dark']))->toEqual(array_keys($scheme['light']))
        ->and($scheme['light'])->toHaveKeys(['primary', 'on-primary', 'tertiary-container', 'surface-container-high', 'outline-variant', 'success', 'on-warning-container', 'info-container'])
        ->and($scheme['light']['surface'])->not->toBe($scheme['dark']['surface'])
        ->and($scheme['light']['inverse-success'])->toBe($scheme['dark']['success']);

    foreach (['light' => "[data-theme='light']", 'dark' => "[data-theme='dark']"] as $theme => $selector) {
        $block = Str::of($stylesheet)->after($selector)->before('}')->toString();

        expect($block)->toContain("color-scheme: {$theme};");

        foreach ($scheme[$theme] as $role => $hex) {
            expect($block)->toContain("--md-sys-color-{$role}: {$hex};");
        }
    }

    expect($stylesheet)->toContain('php artisan material:scheme "#4f46e5" --variant=tonal-spot');
});

it('writes M3\'s three contrast levels for both themes, keyed on data-contrast', function () {
    $this->artisan('material:scheme', ['seed' => '#4f46e5', '--output' => $this->stylesheet])
        ->assertSuccessful();

    $scheme = json_decode(File::get($this->data), true);
    $stylesheet = File::get($this->stylesheet);

    // The standard level keeps the 1.x shape at the top; the other two sit under `contrast`.
    expect(array_keys($scheme['contrast']))->toBe(['standard', 'medium', 'high'])
        ->and(array_keys($scheme['contrast']['medium']['light']))->toEqual(array_keys($scheme['light']))
        ->and(array_keys($scheme['contrast']['high']['dark']))->toEqual(array_keys($scheme['dark']));

    foreach (['medium', 'high'] as $level) {
        foreach (['light' => "[data-contrast='{$level}'] [data-theme='light'] {", 'dark' => "[data-contrast='{$level}'] [data-theme='dark'] {"] as $theme => $selector) {
            $block = Str::of($stylesheet)->after($selector)->before('}')->toString();

            expect($block)->toContain("color-scheme: {$theme};");

            foreach ($scheme['contrast'][$level][$theme] as $role => $hex) {
                expect($block)->toContain("--md-sys-color-{$role}: {$hex};");
            }
        }

        expect($stylesheet)
            ->toContain("[data-contrast='{$level}'],\n[data-contrast='{$level}'][data-theme='light'],")
            ->toContain("[data-contrast='{$level}'][data-theme='dark'],");
    }

    // Every level differs from the one below it, in both themes and for the state colours too.
    foreach (['light', 'dark'] as $theme) {
        foreach (['on-surface-variant', 'outline', 'success', 'info', 'success-container'] as $role) {
            expect($scheme['contrast']['medium'][$theme][$role])
                ->not->toBe($scheme[$theme][$role], "medium {$theme} {$role}")
                ->not->toBe($scheme['contrast']['high'][$theme][$role], "high {$theme} {$role}");
        }

        // The state colours are dynamic colours now, so the level reaches them as it does a
        // built-in role. (A container whose tone already clears the level's ratio stays put,
        // exactly as error's does — hence the pairs rather than every one of the four.)
        foreach (['success', 'warning', 'info'] as $state) {
            foreach ([$state, "on-{$state}", "on-{$state}-container"] as $role) {
                expect($scheme['contrast']['high'][$theme][$role])->not->toBe($scheme[$theme][$role], "high {$theme} {$role}");
            }
        }
    }

    expect($stylesheet)->not->toContain('prefers-contrast');
});

it('puts a level\'s nested light blocks after the dark ones of the level below', function () {
    $this->artisan('material:scheme', ['seed' => '#4f46e5', '--output' => $this->stylesheet])
        ->assertSuccessful();

    $stylesheet = File::get($this->stylesheet);
    $at = fn (string $selector): int => strpos($stylesheet, $selector);

    // A light panel inside a dark high-contrast page: its rule carries one attribute more than
    // the plain dark block and stands after it, so it wins on specificity and on order.
    expect($at("[data-theme='dark'] {"))->toBeLessThan($at("[data-contrast='high'] [data-theme='light'] {"))
        ->and($at("[data-contrast='medium'] [data-theme='light'] {"))->toBeLessThan($at("[data-contrast='medium'][data-theme='dark'],"))
        ->and($at("[data-contrast='medium'][data-theme='dark'],"))->toBeLessThan($at("[data-contrast='high'],"));
});

it('generates the levels for every profile, under its own data-scheme', function () {
    config(['livewire-material.profiles' => [
        'indigo' => ['seed' => '#4f46e5', 'variant' => 'vibrant'],
        'teal' => ['seed' => '#00897b', 'variant' => 'vibrant'],
    ]]);

    $this->artisan('material:scheme', ['--output' => $this->stylesheet])->assertSuccessful();

    $scheme = json_decode(File::get($this->data), true);
    $stylesheet = File::get($this->stylesheet);

    foreach ($scheme['profiles'] as $name => $profile) {
        foreach (['medium', 'high'] as $level) {
            $selector = "[data-scheme='{$name}'][data-contrast='{$level}'] [data-theme='dark'] {";

            expect(Str::of($stylesheet)->after($selector)->before('}')->toString())
                ->toContain("--md-sys-color-primary: {$profile['contrast'][$level]['dark']['primary']};")
                ->and($profile['contrast'][$level]['light']['success'])->not->toBe($profile['light']['success']);
        }
    }

    // The default profile's plain blocks come first, its levels next, then every profile's.
    expect(strpos($stylesheet, "[data-contrast='high'],"))->toBeLessThan(strpos($stylesheet, "[data-scheme='indigo'],"));
});

it('refuses a standard contrast level at or above the medium one', function () {
    $this->artisan('material:scheme', ['seed' => '#4f46e5', '--contrast' => '0.5', '--output' => $this->stylesheet])
        ->expectsOutputToContain('Medium (0.5) and high (1) are always generated')
        ->assertFailed();

    expect(File::exists($this->stylesheet))->toBeFalse();

    config(['livewire-material.profiles' => ['indigo' => ['seed' => '#4f46e5', 'contrast' => 1]]]);

    $this->artisan('material:scheme', ['--output' => $this->stylesheet])
        ->expectsOutputToContain('Profile "indigo": The contrast level 1')
        ->assertFailed();
});

it('keeps a standard level below medium, and records it in the header', function () {
    $this->artisan('material:scheme', ['seed' => '#4f46e5', '--contrast' => '0.3', '--output' => $this->stylesheet])
        ->assertSuccessful();

    $scheme = json_decode(File::get($this->data), true);

    expect($scheme['contrast']['standard'])->toBe(0.3)
        ->and($scheme['light']['primary'])->not->toBe($scheme['contrast']['medium']['light']['primary'])
        ->and(File::get($this->stylesheet))->toContain('php artisan material:scheme "#4f46e5" --variant=tonal-spot --contrast=0.3');
});

it('harmonises the state colours towards the seed only when asked', function () {
    $this->artisan('material:scheme', ['seed' => '#4f46e5', '--output' => $this->stylesheet])->assertSuccessful();
    $plain = json_decode(File::get($this->data), true);

    $this->artisan('material:scheme', ['seed' => '#4f46e5', '--harmonize' => true, '--output' => $this->stylesheet])->assertSuccessful();
    $harmonized = json_decode(File::get($this->data), true);

    expect($harmonized['harmonize'])->toBeTrue()
        ->and($plain['harmonize'])->toBeFalse()
        ->and(File::get($this->stylesheet))->toContain('--variant=tonal-spot --harmonize');

    foreach (['success', 'warning', 'info'] as $state) {
        expect(schemeHueDistance($harmonized['light'][$state], '#4f46e5'))
            ->toBeLessThan(schemeHueDistance($plain['light'][$state], '#4f46e5'), "{$state} moved towards the seed")
            ->and($harmonized['contrast']['high']['dark'][$state])->not->toBe($plain['contrast']['high']['dark'][$state]);
    }
});

it('generates a different scheme per variant', function () {
    $this->artisan('material:scheme', ['seed' => '#4f46e5', '--variant' => 'vibrant', '--output' => $this->stylesheet])
        ->assertSuccessful();

    $vibrant = json_decode(File::get($this->data), true);

    $this->artisan('material:scheme', ['seed' => '#4f46e5', '--output' => $this->stylesheet])
        ->assertSuccessful();

    $tonalSpot = json_decode(File::get($this->data), true);

    expect($vibrant['variant'])->toBe('vibrant')
        ->and($vibrant['light']['primary'])->not->toBe($tonalSpot['light']['primary']);
});

it('generates with the 2021 colour spec when asked, and records it', function () {
    $this->artisan('material:scheme', [
        'seed' => '#00bc7d',
        '--variant' => 'vibrant',
        '--success' => '#00d390',
        '--warning' => '#fcb700',
        '--info' => '#00bafe',
        '--spec' => '2021',
        '--output' => $this->stylesheet,
    ])->assertSuccessful();

    $scheme = json_decode(File::get($this->data), true);

    expect($scheme['spec'])->toBe('2021')
        ->and($scheme['dark'])->toMatchArray([
            'surface' => '#0b1610',
            'primary' => '#00e297',
            'on-primary' => '#003822',
            'success' => '#2ce19c',
            'warning' => '#ffbb16',
            'info' => '#80cfff',
        ])
        ->and($scheme['light'])->toMatchArray([
            'surface' => '#f0fdf2',
            'primary' => '#006c46',
            'success' => '#006c48',
            'warning' => '#7c5800',
            'info' => '#00658c',
        ])
        ->and(File::get($this->stylesheet))
        ->toContain('(spec 2021)')
        ->toContain('php artisan material:scheme "#00bc7d" --variant=vibrant --spec=2021 --success="#00d390" --warning="#fcb700" --info="#00bafe"'."\n");
});

it('refuses an unknown colour spec', function () {
    $this->artisan('material:scheme', ['seed' => '#4f46e5', '--spec' => '2023', '--output' => $this->stylesheet])
        ->expectsOutputToContain('Unknown spec "2023". Use one of: 2021, 2025.')
        ->assertFailed();

    expect(File::exists($this->stylesheet))->toBeFalse();
});

it('refuses a seed that is not a colour', function () {
    $this->artisan('material:scheme', ['seed' => 'indigo', '--output' => $this->stylesheet])
        ->expectsOutputToContain('#rrggbb')
        ->assertFailed();

    expect(File::exists($this->stylesheet))->toBeFalse();
});

it('refuses an unknown variant', function () {
    $this->artisan('material:scheme', ['seed' => '#4f46e5', '--variant' => 'loud', '--output' => $this->stylesheet])
        ->expectsOutputToContain('Unknown variant "loud"')
        ->assertFailed();
});

it('fails without writing anything when node cannot run', function () {
    config(['livewire-material.node' => '/nonexistent/node']);

    $this->artisan('material:scheme', ['seed' => '#4f46e5', '--output' => $this->stylesheet])
        ->assertFailed();

    expect(File::exists($this->stylesheet))->toBeFalse();
});

it('generates every configured profile into one stylesheet keyed by data-scheme', function () {
    config([
        'livewire-material.profiles' => [
            'indigo' => ['label' => 'Indigo', 'seed' => '#4f46e5', 'variant' => 'vibrant'],
            'teal' => ['label' => 'Teal', 'seed' => '#00897b', 'variant' => 'vibrant'],
            'graphite' => ['seed' => '#5f6368', 'variant' => 'neutral'],
        ],
        'livewire-material.profile' => 'teal',
    ]);

    $this->artisan('material:scheme', ['--output' => $this->stylesheet])->assertSuccessful();

    $scheme = json_decode(File::get($this->data), true);
    $stylesheet = File::get($this->stylesheet);

    expect($scheme['default'])->toBe('teal')
        ->and(array_keys($scheme['profiles']))->toBe(['indigo', 'teal', 'graphite'])
        ->and($scheme['profiles']['graphite'])->label->toBe('Graphite')->variant->toBe('neutral')
        ->and($scheme['profiles']['indigo']['light']['primary'])->not->toBe($scheme['profiles']['teal']['light']['primary'])
        // The top level is the default profile, as a 1.0 reader expects.
        ->and($scheme['light'])->toBe($scheme['profiles']['teal']['light'])
        ->and($scheme['dark'])->toBe($scheme['profiles']['teal']['dark'])
        ->and($scheme['seed'])->toBe('#00897b')
        ->and($stylesheet)->toContain('php artisan material:scheme'."\n");

    // The default's plain blocks come first, so a profile's single-attribute selector follows :root.
    expect(strpos($stylesheet, ":root,\n[data-theme='light'] {"))->toBeLessThan(strpos($stylesheet, "[data-scheme='indigo'],"));

    foreach ($scheme['profiles'] as $name => $profile) {
        foreach (['light' => "[data-scheme='{$name}'] [data-theme='light'] {", 'dark' => "[data-scheme='{$name}'] [data-theme='dark'] {"] as $theme => $selector) {
            $block = Str::of($stylesheet)->after($selector)->before('}')->toString();

            expect($block)->toContain("color-scheme: {$theme};")
                ->toContain("--md-sys-color-primary: {$profile[$theme]['primary']};")
                ->toContain("--md-sys-color-surface: {$profile[$theme]['surface']};");
        }
    }
});

it('takes a profile\'s own spec and state colours, and the command\'s for a profile without them', function () {
    config([
        'livewire-material.profiles' => [
            'expressive' => ['seed' => '#00bc7d', 'variant' => 'vibrant'],
            'classic' => ['seed' => '#00bc7d', 'variant' => 'vibrant', 'spec' => 2021, 'success' => '#00d390', 'warning' => '#fcb700', 'info' => '#00bafe'],
        ],
    ]);

    $this->artisan('material:scheme', ['--info' => '#00bafe', '--output' => $this->stylesheet])->assertSuccessful();

    $profiles = json_decode(File::get($this->data), true)['profiles'];

    expect($profiles['classic'])->spec->toBe('2021')
        ->and($profiles['classic']['dark'])->toMatchArray(['primary' => '#00e297', 'success' => '#2ce19c', 'warning' => '#ffbb16', 'info' => '#80cfff'])
        ->and($profiles['expressive'])->spec->toBe('2025')
        ->and($profiles['expressive']['dark']['primary'])->not->toBe('#00e297')
        ->and($profiles['expressive']['dark']['success'])->not->toBe('#2ce19c')
        // The state colours follow the spec now, so the same source is not the same colour.
        ->and($profiles['expressive']['dark']['info'])->not->toBe('#80cfff')
        ->and(File::get($this->stylesheet))
        ->toContain('(spec 2025)')
        ->toMatch('/ \*     classic\s+#00bc7d, vibrant, spec 2021\n/')
        ->toMatch('/ \*     expressive\s+#00bc7d, vibrant\n/');
});

it('names the profile whose spec is unknown', function () {
    config(['livewire-material.profiles' => ['indigo' => ['seed' => '#4f46e5', 'spec' => '2019']]]);

    $this->artisan('material:scheme', ['--output' => $this->stylesheet])
        ->expectsOutputToContain('Profile "indigo": Unknown spec "2019"')
        ->assertFailed();
});

it('names the profile a generator error belongs to', function () {
    config(['livewire-material.profiles' => ['indigo' => ['seed' => '#4f46e5'], 'broken' => ['seed' => 'teal']]]);

    $this->artisan('material:scheme', ['--output' => $this->stylesheet])
        ->expectsOutputToContain('Profile "broken"')
        ->assertFailed();

    expect(File::exists($this->stylesheet))->toBeFalse();
});

it('asks for a seed or profiles when it has neither', function () {
    config(['livewire-material.profiles' => []]);

    $this->artisan('material:scheme', ['--output' => $this->stylesheet])
        ->expectsOutputToContain('livewire-material.profiles')
        ->assertFailed();
});

it('refuses a profile name that cannot be an attribute value', function () {
    config(['livewire-material.profiles' => ['Ocean Blue' => ['seed' => '#0b57d0']]]);

    $this->artisan('material:scheme', ['--output' => $this->stylesheet])
        ->expectsOutputToContain('"Ocean Blue" is not')
        ->assertFailed();
});