feat(pygal): implement bar-stacked-labeled

[github-actions]

Implementation: bar-stacked-labeled - python/pygal

Implements the python/pygal version of bar-stacked-labeled.

File: plots/bar-stacked-labeled/implementations/python/pygal.py

Parent Issue: #3504

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🤖 impl-generate workflow

[claude]

AI Review - Attempt 1/3

Image Description

Light render (plot-light.png): The plot displays a warm off-white background (#FAF8F1) with dark text throughout. Four stacked bar segments per quarter are shown in the Okabe-Ito palette: green (#009E73) at the base representing Electronics, orange (#D55E00) for Furniture, blue (#0072B2) for Clothing, and pink (#CC79A7) for Accessories. Total labels ($312K, $330K, $408K, $500K) appear above each bar stack. The x-axis shows quarters (Q1–Q4), y-axis shows Revenue ($K) with subtle grid lines. Title, axis labels, tick labels, and legend are all clearly readable against the light background with dark text—no light-on-light issues.

Dark render (plot-dark.png): The same plot on a warm near-black background (#1A1A17) with light text. The four stacked segment colors are identical to the light render (green, orange, blue, pink)—only the chrome (title, axis labels, grid, legend text) flips to light colors for readability. All text is clearly visible against the dark background with no dark-on-dark failures. Grid lines are subtle but visible. The brand green (#009E73) stands out distinctly on the dark surface. Both renders pass complete theme-readability checks.

Score: 86/100

Category	Score	Max
Visual Quality	29	30
Design Excellence	11	20
Spec Compliance	15	15
Data Quality	15	15
Code Quality	10	10
Library Mastery	6	10
Total	86	100

Visual Quality (29/30)

• VQ-01: Text Legibility (7/8) - All text readable in both themes; total labels visible but could be more prominent
• VQ-02: No Overlap (6/6) - No text collisions, bar segments clearly distinguished
• VQ-03: Element Visibility (6/6) - All segments visible and distinguishable
• VQ-04: Color Accessibility (2/2) - Okabe-Ito palette is CVD-safe
• VQ-05: Layout & Canvas (4/4) - Proper 4800×2700 landscape with appropriate margins
• VQ-06: Axis Labels & Title (2/2) - Descriptive with units
• VQ-07: Palette Compliance (2/2) - First series #009E73, correct order, backgrounds match spec

Design Excellence (11/20)

• DE-01: Aesthetic Sophistication (4/8) - Functional with theme-aware styling, but limited aesthetic sophistication
• DE-02: Visual Refinement (3/6) - Clean layout with good margins; could use enhanced polish
• DE-03: Data Storytelling (4/6) - Total labels aid storytelling; could be more pronounced

Spec Compliance (15/15)

• SC-01: Plot Type (5/5) - Correct stacked bar using pygal.StackedBar()
• SC-02: Required Features (4/4) - Total labels above bars, multiple stacked series, proper formatting
• SC-03: Data Mapping (3/3) - X-axis quarters, Y-axis revenue, all data shown
• SC-04: Title & Legend (3/3) - Title format correct, legend labels match

Data Quality (15/15)

• DQ-01: Feature Coverage (6/6) - Shows all stacked bar aspects
• DQ-02: Realistic Context (5/5) - Realistic quarterly sales scenario
• DQ-03: Appropriate Scale (4/4) - Sensible values with appropriate units

Code Quality (10/10)

• CQ-01: KISS Structure (3/3) - Simple procedural code, no unnecessary complexity
• CQ-02: Reproducibility (2/2) - Deterministic data, no randomness
• CQ-03: Clean Imports (2/2) - Only necessary imports; path conflict resolution is correct
• CQ-04: Code Elegance (2/2) - Appropriate complexity; no faked interactivity
• CQ-05: Output & API (1/1) - Correct output format and current API usage

Library Mastery (6/10)

• LM-01: Idiomatic Usage (4/5) - Correct use of Style object for theming; proper high-level API
• LM-02: Distinctive Features (2/5) - Uses Style theming and HTML export, but doesn't showcase pygal's advanced interactive capabilities

Score Caps Applied

• None

Strengths

• Correct implementation of stacked bar chart specification with proper pygal.StackedBar() usage
• Theme-adaptive styling with Okabe-Ito palette correctly applied—first series is brand green (#009E73) as required
• Total value labels prominently displayed above each bar stack
• Both light and dark renders perfectly readable with no legibility issues
• Clean, simple code structure with intelligent import conflict resolution
• Realistic, contextual data (quarterly product revenue, good example of part-to-whole visualization)
• Correct file output format (plot-{THEME}.png and .html for interactive library)

Weaknesses

• Total labels could be larger or bolder for greater visual prominence and impact
• Design excellence is minimal—the implementation is functional and correct but lacks aesthetic sophistication
• Limited showcase of pygal's distinctive interactive visualization capabilities (HTML output is minimal)
• Could benefit from visual refinement beyond the standard Style object defaults (custom styling choices)

Issues Found

1. DE-01 LOW: Functional but not aesthetically sophisticated
   • Fix: Enhance visual polish through refined color choices, custom grid styling, or legend positioning tweaks
2. LM-02 LOW: Doesn't showcase distinctive pygal features
   • Fix: Consider leveraging pygal's interactive capabilities more prominently (interactive tooltips, range selection, etc.)

AI Feedback for Next Attempt

Solid foundation. To improve the score: (1) increase label font sizes or add bold weight to total labels for greater prominence; (2) add visual refinement through grid styling adjustments or legend enhancements; (3) leverage pygal's interactive features more to demonstrate library mastery. The core implementation is correct—these are polish improvements.

Verdict: APPROVED

[github-actions]

🔧 Repair Attempt 1/4

Applied fixes based on AI review feedback.

Status: Repair completed, re-triggering review...

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🤖 impl-repair

[claude]

AI Review - Attempt 2/3

Image Description

Light render (plot-light.png): A stacked bar chart on warm off-white (#FAF8F1) background with four quarters (Q1–Q4) on the x-axis and revenue values on the y-axis. Each bar contains four colored segments: green (#009E73) at the base representing Electronics, followed by orange (#D55E00) for Furniture, blue (#0072B2) for Clothing, and pink (#CC79A7) for Accessories. Total labels appear above each stack ($312K, $310K, $408K, $500K) in dark text. Title, axis labels, tick labels, and legend text are all dark and clearly readable. Grid guides are subtle dotted lines. The legend is positioned on the left side.

Dark render (plot-dark.png): The same chart structure on warm near-black (#1A1A17) background. All data colors are identical to the light render (same green, orange, blue, and pink). Chrome elements have adapted: title, axis labels, tick labels, and legend text are now light-colored (#F0EFE8 and #B8B7B0). Total labels above bars are still clearly visible. Grid guides remain subtle. All text is readable against the dark background with no dark-on-dark failures. The data color consistency and theme adaptation demonstrate proper implementation of the style guide.

Score: 88/100

Category	Score	Max
Visual Quality	30	30
Design Excellence	12	20
Spec Compliance	15	15
Data Quality	15	15
Code Quality	10	10
Library Mastery	6	10
Total	88	100

Visual Quality (30/30)

• VQ-01: Text Legibility (8/8) - Font sizes explicitly set; all text perfectly readable in both themes
• VQ-02: No Overlap (6/6) - No overlapping elements; clear spacing throughout
• VQ-03: Element Visibility (6/6) - All segments visible and well-adapted to data
• VQ-04: Color Accessibility (2/2) - Okabe-Ito palette; colorblind-safe; good contrast
• VQ-05: Layout & Canvas (4/4) - Perfect balance; 60-70% canvas utilization; proper margins
• VQ-06: Axis Labels & Title (2/2) - Descriptive labels with units; title format correct
• VQ-07: Palette Compliance (2/2) - First series #009E73; correct Okabe-Ito order; theme-correct backgrounds

Design Excellence (12/20)

• DE-01: Aesthetic Sophistication (4/8) - Well-configured defaults; professional but not exceptional
• DE-02: Visual Refinement (4/6) - Subtle grid, generous whitespace; fairly standard
• DE-03: Data Storytelling (4/6) - Total labels tell the story; functional but not creative

Spec Compliance (15/15)

• SC-01: Plot Type (5/5) - StackedBar correct
• SC-02: Required Features (4/4) - Stacked bars + total labels present
• SC-03: Data Mapping (3/3) - X/Y correctly assigned
• SC-04: Title & Legend (3/3) - Title format correct; legend labels match data

Data Quality (15/15)

• DQ-01: Feature Coverage (6/6) - All products, all quarters, meaningful variation
• DQ-02: Realistic Context (5/5) - Business scenario; neutral; real-world appropriate
• DQ-03: Appropriate Scale (4/4) - Sensible values; logical proportions

Code Quality (10/10)

• CQ-01: KISS Structure (3/3) - Simple, linear flow
• CQ-02: Reproducibility (2/2) - Deterministic hardcoded data
• CQ-03: Clean Imports (2/2) - All imports used
• CQ-04: Code Elegance (2/2) - Pythonic; no over-engineering
• CQ-05: Output & API (1/1) - Correct output format

Library Mastery (6/10)

• LM-01: Idiomatic Usage (4/5) - StackedBar and Style usage is correct
• LM-02: Distinctive Features (2/5) - Basic formatter usage; fairly standard approach

Score Caps Applied

• None

Strengths

• Perfect visual quality with explicit font sizing across all themes
• Flawless spec compliance and data quality
• Clean, reproducible code using idiomatic pygal
• Both light and dark renders pass readability checks with proper theme adaptation
• Realistic, well-chosen business data scenario

Weaknesses

• Design excellence is competent but relies on library defaults without exceptional aesthetic choices
• Library mastery is basic; doesn't leverage distinctive pygal features creatively
• Data storytelling relies solely on total labels without additional visual hierarchy or emphasis

AI Feedback for Next Attempt

N/A - Implementation approved at 88/100 (exceeds ≥80 Review 2 threshold).

Verdict: APPROVED