// Package reporters writes the human-readable + machine-readable
// outputs the pipeline produces. JSON shapes mirror docs/REPORT_SCHEMA.md
// and PROMPT.md verbatim — this package is the contract between the
// harness and any downstream consumer (CI gate, observer, MCP tool).
package reporters

import (
	"crypto/sha256"
	"encoding/hex"
	"encoding/json"
	"os"
	"path/filepath"
	"time"

	"local-review-harness/internal/analyzers"
	"local-review-harness/internal/git"
	"local-review-harness/internal/scanner"
)

// RepoIntake mirrors REVIEW_PIPELINE.md Phase 0 schema.
type RepoIntake struct {
	RepoPath            string         `json:"repo_path"`
	CurrentBranch       string         `json:"current_branch"`
	LatestCommit        string         `json:"latest_commit"`
	GitStatus           string         `json:"git_status"`
	HasGit              bool           `json:"has_git"`
	FileCount           int            `json:"file_count"`
	LanguageBreakdown   map[string]int `json:"language_breakdown"`
	LargestFiles        []LargestFile  `json:"largest_files"`
	DependencyManifests []string       `json:"dependency_manifests"`
	TestManifests       []string       `json:"test_manifests"`
	GeneratedAt         string         `json:"generated_at"`
}

type LargestFile struct {
	Path  string `json:"path"`
	Size  int64  `json:"size"`
	Lines int    `json:"lines,omitempty"`
}

// StaticFindings is the wrapper shape with summary counts.
type StaticFindings struct {
	GeneratedAt string                `json:"generated_at"`
	Findings    []analyzers.Finding   `json:"findings"`
	Summary     FindingsSummary       `json:"summary"`
}

type FindingsSummary struct {
	Total           int `json:"total"`
	Confirmed       int `json:"confirmed"`
	Suspected       int `json:"suspected"`
	Rejected        int `json:"rejected"`
	Critical        int `json:"critical"`
	High            int `json:"high"`
	Medium          int `json:"medium"`
	Low             int `json:"low"`
	BySource        map[string]int `json:"by_source"`
	ByCheck         map[string]int `json:"by_check"`
}

// Receipt mirrors REPORT_SCHEMA.md "Receipt Schema". One per run.
type Receipt struct {
	RunID       string         `json:"run_id"`
	RepoPath    string         `json:"repo_path"`
	StartedAt   string         `json:"started_at"`
	FinishedAt  string         `json:"finished_at"`
	Phases      []PhaseReceipt `json:"phases"`
	Summary     FindingsSummary `json:"summary"`
}

type PhaseReceipt struct {
	Name        string   `json:"name"`
	Status      string   `json:"status"` // ok|degraded|failed|skipped
	InputHash   string   `json:"input_hash,omitempty"`
	OutputHash  string   `json:"output_hash,omitempty"`
	OutputFiles []string `json:"output_files,omitempty"`
	Errors      []string `json:"errors,omitempty"`
}

// BuildIntake assembles the Phase 0 intake JSON from the scanner +
// git probes. Doesn't write — the pipeline owns file I/O.
func BuildIntake(scan *scanner.Result, gi git.Info) RepoIntake {
	largest := make([]LargestFile, 0, len(scan.LargestFiles))
	for _, f := range scan.LargestFiles {
		largest = append(largest, LargestFile{Path: f.Path, Size: f.Size, Lines: f.Lines})
	}
	return RepoIntake{
		RepoPath:            scan.RepoPath,
		CurrentBranch:       gi.CurrentBranch,
		LatestCommit:        gi.LatestCommit,
		GitStatus:           gi.Status,
		HasGit:              gi.HasGit,
		FileCount:           len(scan.Files),
		LanguageBreakdown:   scan.LanguageBreakdown,
		LargestFiles:        largest,
		DependencyManifests: scan.DependencyManifests,
		TestManifests:       scan.TestManifests,
		GeneratedAt:         time.Now().UTC().Format(time.RFC3339Nano),
	}
}

// SummarizeFindings is the canonical roll-up. Used by both the
// per-phase JSON and the receipt summary.
func SummarizeFindings(findings []analyzers.Finding) FindingsSummary {
	out := FindingsSummary{
		Total:    len(findings),
		BySource: map[string]int{},
		ByCheck:  map[string]int{},
	}
	for _, f := range findings {
		switch f.Status {
		case analyzers.StatusConfirmed:
			out.Confirmed++
		case analyzers.StatusSuspected:
			out.Suspected++
		case analyzers.StatusRejected:
			out.Rejected++
		}
		switch f.Severity {
		case analyzers.SeverityCritical:
			out.Critical++
		case analyzers.SeverityHigh:
			out.High++
		case analyzers.SeverityMedium:
			out.Medium++
		case analyzers.SeverityLow:
			out.Low++
		}
		out.BySource[string(f.Source)]++
		if f.CheckID != "" {
			out.ByCheck[f.CheckID]++
		}
	}
	return out
}

// WriteJSON marshals + writes; sha256 returned for receipt cross-link.
func WriteJSON(path string, v any) (sha string, err error) {
	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
		return "", err
	}
	bs, err := json.MarshalIndent(v, "", "  ")
	if err != nil {
		return "", err
	}
	bs = append(bs, '\n')
	if err := os.WriteFile(path, bs, 0o644); err != nil {
		return "", err
	}
	h := sha256.Sum256(bs)
	return hex.EncodeToString(h[:])[:16], nil
}