import {
    ANATOMY_CHAPTER,
    DATA_FLOW_TAG,
    FINDINGS_TAG,
    FLOW_TAG,
    IMPORTS_TAG,
    LAYERS_TAG,
    LEGEND_TAG,
    MEASUREMENTS_TAG,
    SAMPLE_WALK_TAG,
    STRUCTURE_TAG,
} from "#configuration/strings/anatomy.strings";
import type { AnatomyFolder, AnatomyMetrics, AnatomySnapshot, AnatomyStats } from "#types/anatomy.types";
import {
    BLANK_LABEL,
    BYTES_LABEL,
    CALLABLE_LABEL,
    DEFINITIONS_LABEL,
    EDGES_LABEL,
    EXPORTED_LABEL,
    FILES_LABEL,
    FINDINGS_CLEAN,
    FINDINGS_LABEL,
    FINDING_SUFFIX,
    FLOWS_LABEL,
    FLOW_SUFFIX,
    LINES_LABEL,
    MAX_IN_LABEL,
    MAX_OUT_LABEL,
    NONE_FOUND,
    NO_ANOMALIES,
    RESOLUTION_LABEL,
    UNRESOLVED_LABEL,
} from "#configuration/strings/folder.strings";
import type { Block, Metric } from "#types/block.types";
import { CHART_TAGS, KEY_SEPARATOR, STATS_SEPARATOR, WIDE_CHARTS } from "#configuration/constants/anatomy.constants";
import {
    DERIVED_SECTION_ID,
    DIAGNOSES_SECTION_ID,
    PARTS_SECTION_ID,
    SPINE_SECTION_ID,
    WALK_SECTION_ID,
} from "#core/ids/anatomy.ids";
import { LINE_BREAK, TEXT_LANGUAGE } from "#configuration/constants/code.constants";
import { importsDiagram, structureDiagram } from "#domain/converters/graph.converter";
import { LABEL_SEPARATOR } from "#configuration/strings/ontology.strings";
import type { Section } from "#types/document.types";
import { codeOf } from "#domain/converters/ontology.converter";

const metric = function metric(label: string, value: number | string): Metric {
    return { label, value: String(value) };
};

const tallyMetrics = function tallyMetrics(
    counts: Readonly<Record<string, number>>,
    suffix: string,
    emptyLabel: string,
    emptyValue: string = NONE_FOUND,
): Metric[] {
    const sorted = Object.entries(counts).sort((a, b) => b[1] - a[1] || a[0].localeCompare(b[0]));
    return sorted.length === 0
        ? [metric(emptyLabel, emptyValue)]
        : sorted.map(([key, count]) => metric(key + suffix, count));
};

export const statsMetrics = function statsMetrics(stats: AnatomyStats): Metric[] {
    return [
        metric(FILES_LABEL, stats.files),
        metric(LINES_LABEL, stats.lines.code),
        metric(BLANK_LABEL, stats.lines.blank),
        metric(BYTES_LABEL, stats.bytes),
        metric(DEFINITIONS_LABEL, stats.definitions),
        metric(EXPORTED_LABEL, stats.exported),
        metric(CALLABLE_LABEL, stats.callable),
        metric(EDGES_LABEL, stats.edges),
        ...tallyMetrics(stats.flows, FLOW_SUFFIX, FLOWS_LABEL),
        ...tallyMetrics(stats.findings, FINDING_SUFFIX, FINDINGS_LABEL, NO_ANOMALIES),
    ];
};

const moduleMetrics = function moduleMetrics(metrics: AnatomyMetrics, stats: AnatomyStats): Metric[] {
    return [
        metric(FILES_LABEL, stats.files),
        metric(LINES_LABEL, stats.lines.code),
        metric(DEFINITIONS_LABEL, metrics.definitions),
        metric(EXPORTED_LABEL, metrics.exported),
        metric(CALLABLE_LABEL, metrics.callable),
        metric(EDGES_LABEL, metrics.edges),
        metric(UNRESOLVED_LABEL, metrics.unresolvedCalls),
        metric(RESOLUTION_LABEL, metrics.resolutionRate),
        metric(MAX_IN_LABEL, metrics.maxInDegree),
        metric(MAX_OUT_LABEL, metrics.maxOutDegree),
        ...tallyMetrics(metrics.flows, FLOW_SUFFIX, FLOWS_LABEL),
        ...tallyMetrics(metrics.findings, FINDING_SUFFIX, FINDINGS_LABEL, NO_ANOMALIES),
    ];
};

const chartBlocks = function chartBlocks(snapshot: AnatomySnapshot, ids: readonly string[]): Block[] {
    return ids.flatMap((id) => {
        const chart = snapshot.charts.find((candidate) => candidate.id === id);
        const [part] = chart?.parts ?? [];
        const caption = CHART_TAGS.get(id);
        return chart === undefined || part === undefined || caption === undefined
            ? []
            : [{ caption, kind: "mermaid", text: part.text, wide: WIDE_CHARTS.has(id) }];
    });
};

const INDENT = "  ";

const layersText = function layersText(folder: AnatomyFolder, depth = 0): string[] {
    const own =
        folder.path === ""
            ? []
            : [INDENT.repeat(depth) + folder.name + (folder.layer === null ? "" : LABEL_SEPARATOR + folder.layer)];
    return [...own, ...folder.folders.flatMap((child) => layersText(child, folder.path === "" ? depth : depth + 1))];
};

const findingsText = function findingsText(snapshot: AnatomySnapshot): string {
    if (snapshot.findings.length === 0) {
        return FINDINGS_CLEAN;
    }
    return snapshot.findings
        .map((finding) =>
            [finding.kind, finding.severity, finding.file + KEY_SEPARATOR + finding.name, finding.detail].join(
                STATS_SEPARATOR,
            ),
        )
        .join(LINE_BREAK);
};

const legendText = function legendText(snapshot: AnatomySnapshot): string {
    return snapshot.states.map((state) => state.state + LABEL_SEPARATOR + state.text).join(LINE_BREAK);
};

const walkFolders = function walkFolders(folder: AnatomyFolder): AnatomyFolder[] {
    return [
        ...(folder.walk === null || folder.files.length === 0 ? [] : [folder]),
        ...folder.folders.flatMap(walkFolders),
    ];
};

const sampleWalk = function sampleWalk(snapshot: AnatomySnapshot): Block[] {
    const [smallest] = walkFolders(snapshot.tree).sort((a, b) => (a.walk?.steps ?? 0) - (b.walk?.steps ?? 0));
    return smallest?.walk === null || smallest === undefined
        ? []
        : [{ caption: SAMPLE_WALK_TAG, kind: "walk", walk: smallest.walk }];
};

const panelsOf = function panelsOf(snapshot: AnatomySnapshot): ReadonlyMap<string, readonly Block[]> {
    return new Map<string, readonly Block[]>([
        [
            DERIVED_SECTION_ID,
            [
                {
                    caption: MEASUREMENTS_TAG,
                    kind: "metric",
                    metrics: moduleMetrics(snapshot.metrics, snapshot.tree.stats),
                    wide: true,
                },
                { caption: IMPORTS_TAG, kind: "mermaid", text: importsDiagram(snapshot), wide: true },
            ],
        ],
        [
            PARTS_SECTION_ID,
            [
                { caption: STRUCTURE_TAG, kind: "mermaid", text: structureDiagram(snapshot) },
                ...chartBlocks(
                    snapshot,
                    [...CHART_TAGS.keys()].filter((id) => CHART_TAGS.get(id) === FLOW_TAG),
                ),
            ],
        ],
        [
            SPINE_SECTION_ID,
            [
                codeOf(LAYERS_TAG, layersText(snapshot.tree).join(LINE_BREAK), TEXT_LANGUAGE),
                ...chartBlocks(
                    snapshot,
                    [...CHART_TAGS.keys()].filter((id) => CHART_TAGS.get(id) === DATA_FLOW_TAG),
                ),
            ],
        ],
        [DIAGNOSES_SECTION_ID, [codeOf(FINDINGS_TAG, findingsText(snapshot), TEXT_LANGUAGE), ...sampleWalk(snapshot)]],
        [WALK_SECTION_ID, [codeOf(LEGEND_TAG, legendText(snapshot), TEXT_LANGUAGE)]],
    ]);
};

const withPanels = function withPanels(section: Section, panels: readonly Block[]): Section {
    const last = section.subsections.at(-1);
    if (last === undefined) {
        return section;
    }
    return {
        ...section,
        subsections: [...section.subsections.slice(0, -1), { ...last, blocks: [...(last.blocks ?? []), ...panels] }],
    };
};

export const anatomyChapter = function anatomyChapter(snapshot: AnatomySnapshot): readonly Section[] {
    const panels = panelsOf(snapshot);
    return ANATOMY_CHAPTER.map((section) => withPanels(section, panels.get(section.id) ?? []));
};