// Cthulhu screen reader.
// Copyright (c) 2026 Storm Dragon
// Authors: Storm Dragon, Angus Kola
//
// This program is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the Free
// Software Foundation, either version 3 of the License, or (at your option)
// any later version.
//
// This program is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
// more details.
//
// You should have received a copy of the GNU General Public License along with
// this program. If not, see <https://www.gnu.org/licenses/gpl-3.0.html>.

package app

import (
	"context"
	"errors"
	"log/slog"

	"git.stormux.org/storm/cthulhu/internal/input"
	"git.stormux.org/storm/cthulhu/internal/presentation"
	"git.stormux.org/storm/cthulhu/internal/review"
)

func flatReviewCommand(command input.Command) (review.FlatUnit, int) {
	switch command {
	case input.ReviewWindowStart:
		return review.WindowStart, 0
	case input.ReviewWindowEnd:
		return review.WindowEnd, 0
	case input.ReviewPreviousLine:
		return review.Line, -1
	case input.ReviewCurrentLine:
		return review.Line, 0
	case input.ReviewNextLine:
		return review.Line, 1
	case input.ReviewPreviousWord:
		return review.Word, -1
	case input.ReviewCurrentWord, input.ReviewSpellWord, input.ReviewPhoneticWord:
		return review.Word, 0
	case input.ReviewNextWord:
		return review.Word, 1
	case input.ReviewPreviousCharacter:
		return review.Character, -1
	case input.ReviewCurrentCharacter, input.ReviewPhoneticCharacter:
		return review.Character, 0
	case input.ReviewNextCharacter:
		return review.Character, 1
	case input.ReviewWordAbove:
		return review.WordAbove, 0
	case input.ReviewWordBelow:
		return review.WordBelow, 0
	case input.ReviewLineEnd:
		return review.LineEnd, 0
	default:
		return 0, 0
	}
}

func presentFlatReviewResult(logger *slog.Logger, speech speechEnqueuer, result review.Result) {
	text := ""
	if result.Err != nil {
		logger.Warn("flat review failed", "error", result.Err)
		switch {
		case errors.Is(result.Err, review.ErrLimitedReview):
			text = "This window exceeds the current flat review text limit."
		case errors.Is(result.Err, review.ErrNoReviewContent):
			text = "No visible content."
		default:
			text = "Could not find current location."
		}
	} else if !result.Moved && (result.FlatStep != 0 || result.FlatUnit == review.WordAbove || result.FlatUnit == review.WordBelow) {
		// Python's sequential review stops silently at window boundaries.
		return
	} else {
		text = presentation.FlatReviewText(result.FlatPosition.Text, result.FlatUnit == review.Character || result.FlatUnit == review.LineEnd)
	}
	speech.Interrupt()
	request := speechRequest{Text: text, Role: "text", Cause: "flat-review", Character: result.Err == nil && (result.FlatUnit == review.Character || result.FlatUnit == review.LineEnd)}
	if result.Err == nil && result.FlatUnit == review.Line {
		request.Line = &speechLine{Object: result.FlatPosition.Object, Raw: result.FlatPosition.Text}
	}
	if result.Err == nil {
		set_review_spelling(&request, result.FlatPosition.Text, result.FlatSpeech)
	}
	speech.Enqueue(request)
	if logger.Enabled(context.Background(), slog.LevelDebug) {
		logger.Debug("queued flat review presentation",
			"speech_text", request.Text, "spelling", request.Spelling, "speech_style", result.FlatSpeech,
			"unit", result.FlatUnit,
			"moved", result.Moved,
			"bus", result.FlatPosition.Object.BusName,
			"object_path", result.FlatPosition.Object.Path,
			"offset", result.FlatPosition.Offset,
			"has_offset", result.FlatPosition.HasOffset,
			"capture_duration", result.CaptureDuration,
			"capture_reason", result.CaptureReason,
		)
	}
}