Feature. Text rotation

[azamat7g]

Description
Adds Rotation (degrees, positive = CCW, negative = CW) and RotationPivot (Horizontal × Vertical axes) to props.Text. Cell auto-expands vertically to fit the rotated bounding box; default Center+Middle pivot keeps single-line
behavior identical to before.

Notable details:

• Text.GetHeight returns the rotated bbox height (w·|sinθ| + h·|cosθ|) so the layout reserves room.
• New Provider.GetStringWidth lets GetHeight use the actual rendered width instead of cell.Width (avoids ~3× over-allocation for short text).
• gofpdf Add hoists line-splitting above the rotation transform so multi-line blocks rotate as one around the correct textHeight-based pivot.
• upExtent is computed from the four rotated corners — covers all 9 pivot combos for any angle/sign.
• ToMap omits the new keys when default → existing snapshots untouched.

Related Issue
N/A

Checklist

• All methods associated with structs has func (<first letter of struct> *struct) method() {} name style.
• Wrote unit tests for new/changed features.
• Followed the unit test when,should naming pattern.
• All mocks created with m := mocks.NewConstructor(t).
• All mocks using m.EXPECT().MethodName() method to mock methods.
• Updated docs/*
• Updated example_test.go.
• Updated README.md
• New public methods/structs/interfaces has comments upside them explaining they responsibilities
• Executed make dod with none issues pointed out by golangci-lint

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: 9ff74a7c-6ba3-4318-b7d7-d4bafc53d042

📥 Commits

Reviewing files that changed from the base of the PR and between 74d201d and 9fa6c5b.

📒 Files selected for processing (1)

• pkg/components/text/text.go

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📝 Walkthrough

Summary by CodeRabbit

• New Features
  • Text component supports rotation (degrees) and configurable rotation anchor (start/center/end × top/middle/bottom).
• Behavior Changes
  • Height and layout calculations updated so rotated multi-line text fits within its cell and aligns to the chosen pivot.
• Documentation
  • Docs updated with rotation usage, pivot rules, and layout/height notes.
• Examples
  • Added example demonstrating rotated text.
• Tests
  • Added tests validating rotated rendering and height calculations.

Walkthrough

Adds text rotation support: new rotation props and pivot constants, provider/interface methods for measuring string width, rotated bounding-box math and pivot-aware positioning in rendering, mock/test updates, example, and documentation updates.

Changes

Cohort / File(s)	Summary
Rotation Pivot Constants pkg/consts/rotationpivot/rotationpivot.go	New package defining horizontal (Start, Center, End) and vertical (Top, Middle, Bottom) pivot types and Pivot struct.
Core Interfaces pkg/core/components.go, pkg/core/provider.go	Added GetStringWidth(text string, textProp *props.Text) float64 to Text and Provider interfaces.
Text Properties pkg/props/text.go, pkg/props/text_test.go	Added Rotation float64 and RotationPivot rotationpivot.Pivot; ToMap() emits rotation fields conditionally; MakeValid() defaults missing pivot axes; tests updated for serialization/validation.
Text Component API & Logic pkg/components/text/text.go, pkg/components/text/text_test.go, pkg/components/text/example_test.go	GetHeight now accounts for rotated bounding-box math (sine/cosine, clamping to content width); tests added for rotation cases; example demonstrating rotated text added.
GoFPDF Provider Implementation internal/providers/gofpdf/provider.go, internal/providers/gofpdf/text.go, internal/providers/gofpdf/text_test.go	Provider exposes GetStringWidth; text rendering computes wrapped lines first, calculates block width/height, alignment and pivot offsets, adjusts Y to fit rotated bounding box, applies TransformRotate around pivot, then renders lines; extensive tests assert transforms and text positions.
Mocks mocks/Provider.go, mocks/Text.go	Added GetStringWidth mock methods and expectation plumbing to both provider and text mocks.
Documentation docs/v2/features/text.md	Documentation extended with Rotation and RotationPivot prop descriptions, usage notes, and rotated height/baseline calculation details.

Sequence Diagram(s)

sequenceDiagram
    participant Component as Text Component
    participant Provider as GoFPDF Provider
    participant PDF as PDF Context

    Component->>Provider: Add(text, props {Rotation, RotationPivot})
    activate Provider
    Provider->>Provider: Determine wrapped lines\nGetStringWidth for measurement
    Provider->>Provider: Compute block width/height\nCompute alignment & pivot offsets
    Provider->>Provider: Calculate rotated bounding-box\nAdjust start Y if needed
    Provider->>PDF: TransformBegin()
    Provider->>PDF: TransformRotate(angle, pivotX, pivotY)
    Provider->>PDF: Text(x, y) for each line
    Provider->>PDF: TransformEnd()
    deactivate Provider

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Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Poem

🐇 Spin the letters, twirl the line,

Pivot set and angle fine,
Sine and cosine do their part,
Every block fits—art to art,
A rabbit hops, and stamps “rendered!” ✨

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title 'Feature. Text rotation' is concise and clearly indicates the main change: adding text rotation capability.
Description check	✅ Passed	The description is comprehensive and follows the template. It explains the feature, details technical aspects, and addresses all applicable checklist items with confirmation marks.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@pkg/components/text/text.go`:
- Around line 72-85: contentWidth can be negative if t.prop.Left + t.prop.Right
> cell.Width which yields invalid heights when rotation math runs; before
calling provider.GetLinesQuantity/GetStringWidth and before using contentWidth
in the rotation block, clamp contentWidth to zero (or math.Max(0, contentWidth))
and use that non-negative value for subsequent calculations (affecting the call
to provider.GetLinesQuantity, the stringWidth clamp and the rotation height math
that updates textHeight); update references to contentWidth,
provider.GetLinesQuantity, provider.GetStringWidth and the rotation block that
computes textHeight to use the guarded value.

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Fix all unresolved CodeRabbit comments on this PR:

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: ASSERTIVE

Plan: Pro

Run ID: fd2ca0d7-df9a-41f5-9e0d-90457dffb08b

📥 Commits

Reviewing files that changed from the base of the PR and between aa2645f and 74d201d.

📒 Files selected for processing (14)

• docs/v2/features/text.md
• internal/providers/gofpdf/provider.go
• internal/providers/gofpdf/text.go
• internal/providers/gofpdf/text_test.go
• mocks/Provider.go
• mocks/Text.go
• pkg/components/text/example_test.go
• pkg/components/text/text.go
• pkg/components/text/text_test.go
• pkg/consts/rotationpivot/rotationpivot.go
• pkg/core/components.go
• pkg/core/provider.go
• pkg/props/text.go
• pkg/props/text_test.go