package builtin

import (
	"context"
	"fmt"

	"gitea.maximumdirect.net/eric/seriatim/internal/autocorrect"
	"gitea.maximumdirect.net/eric/seriatim/internal/backchannel"
	"gitea.maximumdirect.net/eric/seriatim/internal/coalesce"
	"gitea.maximumdirect.net/eric/seriatim/internal/config"
	"gitea.maximumdirect.net/eric/seriatim/internal/model"
	"gitea.maximumdirect.net/eric/seriatim/internal/overlap"
	"gitea.maximumdirect.net/eric/seriatim/internal/report"
)

type noopPostprocessor struct {
	name string
}

func (p noopPostprocessor) Name() string {
	return p.name
}

func (p noopPostprocessor) Process(ctx context.Context, in model.MergedTranscript, cfg config.Config) (model.MergedTranscript, []report.Event, error) {
	if err := ctx.Err(); err != nil {
		return model.MergedTranscript{}, nil, err
	}

	return in, []report.Event{
		report.Info("postprocessing", p.name, "completed no-op postprocessing module"),
	}, nil
}

type assignIDs struct{}

func (assignIDs) Name() string {
	return "assign-ids"
}

func (assignIDs) Process(ctx context.Context, in model.MergedTranscript, cfg config.Config) (model.MergedTranscript, []report.Event, error) {
	if err := ctx.Err(); err != nil {
		return model.MergedTranscript{}, nil, err
	}

	for index := range in.Segments {
		in.Segments[index].ID = index + 1
	}

	return in, []report.Event{
		report.Info("postprocessing", "assign-ids", "assigned final segment IDs"),
	}, nil
}

type detectOverlaps struct{}

func (detectOverlaps) Name() string {
	return "detect-overlaps"
}

func (detectOverlaps) Process(ctx context.Context, in model.MergedTranscript, cfg config.Config) (model.MergedTranscript, []report.Event, error) {
	if err := ctx.Err(); err != nil {
		return model.MergedTranscript{}, nil, err
	}

	in = overlap.Detect(in)
	return in, []report.Event{
		report.Info("postprocessing", "detect-overlaps", fmt.Sprintf("detected %d overlap group(s)", len(in.OverlapGroups))),
	}, nil
}

type resolveOverlaps struct{}

func (resolveOverlaps) Name() string {
	return "resolve-overlaps"
}

func (resolveOverlaps) Process(ctx context.Context, in model.MergedTranscript, cfg config.Config) (model.MergedTranscript, []report.Event, error) {
	if err := ctx.Err(); err != nil {
		return model.MergedTranscript{}, nil, err
	}

	resolved, summary, err := overlap.Resolve(in, cfg.OverlapWordRunGap, cfg.WordRunReorderWindow)
	if err != nil {
		return model.MergedTranscript{}, nil, err
	}

	return resolved, []report.Event{
		report.Info(
			"postprocessing",
			"resolve-overlaps",
			fmt.Sprintf(
				"processed %d overlap group(s); changed %d; removed %d original segment(s); created %d replacement segment(s)",
				summary.GroupsProcessed,
				summary.GroupsChanged,
				summary.OriginalsRemoved,
				summary.ReplacementsCreated,
			),
		),
	}, nil
}

type backchannelPostprocessor struct{}

func (backchannelPostprocessor) Name() string {
	return "backchannel"
}

func (backchannelPostprocessor) Process(ctx context.Context, in model.MergedTranscript, cfg config.Config) (model.MergedTranscript, []report.Event, error) {
	if err := ctx.Err(); err != nil {
		return model.MergedTranscript{}, nil, err
	}

	out, tagged := backchannel.Apply(in)
	return out, []report.Event{
		report.Info("postprocessing", "backchannel", fmt.Sprintf("tagged %d backchannel segment(s)", tagged)),
	}, nil
}

type coalescePostprocessor struct{}

func (coalescePostprocessor) Name() string {
	return "coalesce"
}

func (coalescePostprocessor) Process(ctx context.Context, in model.MergedTranscript, cfg config.Config) (model.MergedTranscript, []report.Event, error) {
	if err := ctx.Err(); err != nil {
		return model.MergedTranscript{}, nil, err
	}

	out, summary := coalesce.Apply(in, cfg.CoalesceGap)
	return out, []report.Event{
		report.Info(
			"postprocessing",
			"coalesce",
			fmt.Sprintf("merged %d original segment(s) into %d coalesced segment(s)", summary.OriginalSegmentsMerged, summary.CoalescedSegments),
		),
	}, nil
}

type autocorrectPostprocessor struct{}

func (autocorrectPostprocessor) Name() string {
	return "autocorrect"
}

func (autocorrectPostprocessor) Process(ctx context.Context, in model.MergedTranscript, cfg config.Config) (model.MergedTranscript, []report.Event, error) {
	if err := ctx.Err(); err != nil {
		return model.MergedTranscript{}, nil, err
	}
	if cfg.AutocorrectFile == "" {
		return in, []report.Event{
			report.Info("postprocessing", "autocorrect", "skipped autocorrect because no autocorrect file was supplied"),
		}, nil
	}

	rules, err := autocorrect.Load(cfg.AutocorrectFile)
	if err != nil {
		return model.MergedTranscript{}, nil, err
	}

	replacements := 0
	for index := range in.Segments {
		var count int
		in.Segments[index].Text, count = rules.Apply(in.Segments[index].Text)
		replacements += count
	}

	return in, []report.Event{
		report.Info("postprocessing", "autocorrect", fmt.Sprintf("applied %d autocorrect replacement(s)", replacements)),
	}, nil
}